CN113103587B

CN113103587B - Control method and control system for 3D printing and 3D printing equipment

Info

Publication number: CN113103587B
Application number: CN202110409788.1A
Authority: CN
Inventors: 荣左超; 于清晓; 马劲松; 陈六三
Original assignee: Shanghai Union Technology Corp
Current assignee: Shanghai Union Technology Corp
Priority date: 2021-04-16
Filing date: 2021-04-16
Publication date: 2022-07-22
Anticipated expiration: 2041-04-16
Also published as: CN113103587A

Abstract

The application discloses a control method, a control system, a 3D printing device, a computer device and a computer readable storage medium for 3D printing, wherein the control method comprises the following steps: when detecting that at least one target printing component in a plurality of target printing components printed currently has a printing defect, acquiring reference slice images of the plurality of target printing components; performing image processing on a reference slice image of at least one target printing component to obtain a contour of the reference slice image; generating a mask image according to the profile, wherein a region corresponding to the profile of at least one target printing member in the mask image is an exposure-inhibited region; the mask image is utilized to carry out the mask operation on the slice images of the target printing components so as to execute the printing operation, the printing process of the normal target printing components can not be interrupted, the interference or pollution of at least one target printing component with printing defects in the printing process is avoided, and the time cost and the material cost are saved.

Description

Control method and control system for 3D printing and 3D printing equipment

Technical Field

The application relates to the field of 3D printing, in particular to a control method and a control system for 3D printing, 3D printing equipment, a computer device and a computer readable storage medium.

Background

3D printing is one of rapid prototyping technologies, which is a technology for constructing an object by using an adhesive material such as powdered metal, plastic, resin, etc. in a layer-by-layer printing manner on the basis of a digital model file. The 3D printing apparatus manufactures a 3D object by performing such a printing technique. The 3D printing equipment has wide application in the fields of dies, customized commodities, medical jigs, prostheses and the like due to high forming precision.

The 3D printing apparatus is, for example, a DLP apparatus and an LCD apparatus suitable for bottom exposure, an SLA apparatus suitable for top exposure, a DLP apparatus, an LCD apparatus, and the like. Taking bottom exposure 3D printing equipment as an example, it is provided with a container with a transparent bottom surface for holding the light-curing material to be cured; the energy radiation system radiates energy to the material on the bottom surface of the container facing the transparent surface, so that the material on the bottom surface of the container is solidified into a solidified layer with the same shape as the radiated shape; in order to fill new material, the cured layer is attached to the component platform under the drive of the Z-axis drive mechanism so that the material fills the gap between the bottom surface of the container and the cured layer, and the above process is repeated to manufacture the 3D object. During the 3D object manufacturing process by the 3D printing apparatus, devices and systems therein may be degraded or abnormal, and during the printing process, the cured layer may be distorted or collapsed, which does not meet the expected printing standard, and therefore, the 3D object manufacturing process by the 3D printing apparatus needs to be monitored to avoid the time and cost loss caused by the printing failure during the curing process.

Disclosure of Invention

In view of the above-mentioned deficiencies of the related art, the present application discloses a control method, a control system, a 3D printing device, a computer apparatus, and a computer readable storage medium for 3D printing, so as to solve the problems in the prior art, such as printing time loss and cost loss, caused by distortion of a cured layer and the like, which may occur in 3D printing.

To achieve the above and other related objects, a first aspect of the disclosure provides a control method for 3D printing, including the steps of: when detecting that at least one target printing component in a plurality of target printing components printed currently has a printing defect, acquiring reference slice images of the plurality of target printing components; performing image processing on a reference slice image of the plurality of target printing components, which corresponds to the at least one target printing component, to obtain a contour of the at least one target printing component; generating a mask image from the profile of the at least one target printing member; wherein a region of the mask image corresponding to the outline of the at least one target printing member is an exposure-inhibited region; masking the slice images of the plurality of target printing members with the mask image to perform a print job.

A second aspect of the present disclosure provides a control system for 3D printing, including: the acquisition module is used for acquiring reference slice images of a plurality of target printing components when detecting that at least one target printing component in the plurality of target printing components which are printed currently has a printing defect; the processing module is used for carrying out image processing on a reference slice image corresponding to the at least one target printing component in the reference slice images of the target printing components to obtain the outline of the at least one target printing component; and generating a mask image according to the contour of the at least one target printing component to enable the 3D printing device to perform a mask operation on the slice images of the plurality of target printing components based on the mask image so as to execute a printing job, wherein the area, corresponding to the contour of the at least one target printing component, in the mask image is an exposure-inhibited area.

A third aspect of the present disclosure provides a control system applied to a 3D printing apparatus, the 3D printing apparatus including: a shaping chamber, an energy radiation system, and a component platform that accumulates a cured layer that is selectively cured by the energy radiation system, the control system comprising: the shooting device is used for shooting images in the forming chamber to obtain current solidified layer images of a plurality of currently printed target printing components; and the processing device is connected with the shooting device and used for detecting whether a target printing component with a printing defect exists or not according to a current cured layer image and a corresponding slice image of a plurality of currently printed target printing components, acquiring a reference slice image of the plurality of target printing components when the condition that at least one target printing component in the plurality of currently printed target printing components has the printing defect is detected, performing image processing on the reference slice image corresponding to the at least one target printing component in the reference slice images of the plurality of target printing components to obtain the contour of the at least one target printing component, and generating a mask image according to the contour of the at least one target printing component, wherein the area corresponding to the contour of the at least one target printing component in the mask image is an exposure-inhibited area.

A fourth aspect of the present disclosure provides a 3D printing apparatus, including: a container for holding a photocurable material to be cured; an energy radiation system for selectively curing the photocurable material according to the data of the received slice image to form a cured layer; a component platform in the container for cumulatively attaching the solidified layer; the Z-axis driving mechanism is connected with the component platform and is used for adjusting the distance between the component platform and the printing reference surface; the control system is used for detecting a plurality of target printing components which are printed currently and generating a mask image corresponding to at least one target printing component when the at least one target printing component is detected to have printing defects, wherein the area corresponding to the outline of at least one target printing component in the mask image is an exposure-inhibited area; and the control device is connected with the Z-axis driving mechanism and the energy radiation system and is used for controlling the Z-axis driving mechanism and the energy radiation system according to the mask image.

A fifth aspect of the present disclosure provides a computer apparatus comprising: storage means for storing at least one program; and the processing device is connected with the storage device and is used for running the at least one program to execute and realize the control method for 3D printing according to any one embodiment of the first aspect of the application.

A sixth aspect of the present disclosure provides a computer-readable storage medium storing at least one program which, when executed by a processor, implements a method of controlling 3D printing according to any one of the embodiments provided in the first aspect of the present disclosure.

In summary, the control method, the control system, the 3D printing apparatus, the computer device, and the computer-readable storage medium for 3D printing according to the present application have the following beneficial technical effects in an embodiment:

when at least one target printing component is detected to have a printing defect in the printing process, image processing is carried out on a reference slice image of the at least one target printing component to obtain a contour corresponding to the at least one target printing component, a mask image is generated according to the contour of the at least one target printing component, wherein a region corresponding to the contour of the at least one target printing component in the mask image is an exposure-inhibited region, and the slice images of the plurality of target printing components are utilized to carry out a mask operation to execute a printing job, so that the printing of the at least one target printing component with the printing defect is stopped, the printing of other normal target printing components can be continued, the printing process is not interrupted, and the interference or pollution of the at least one target printing component with the printing defect on other target printing components in the printing process can be avoided, Photocuring the material, film, or corresponding mechanism, and can save time and material costs.

Other aspects and advantages of the present application will be readily apparent to those skilled in the art from the following detailed description. Only exemplary embodiments of the present application have been shown and described in the following detailed description. As those skilled in the art will recognize, the disclosure of the present application enables those skilled in the art to make changes to the specific embodiments disclosed without departing from the spirit and scope of the invention as it is directed to the present application. Accordingly, the descriptions in the drawings and the specification of the present application are illustrative only and not limiting.

Drawings

The specific features of the invention to which this application relates are set forth in the appended claims. The features and advantages of the invention to which this application relates will be better understood by reference to the exemplary embodiments described in detail below and the accompanying drawings. Brief description of the drawingsthe following:

fig. 1 is a schematic diagram showing a printing breadth range and a slice image corresponding to a solidified layer in an embodiment of the control method for 3D printing.

Fig. 2 is a flowchart illustrating a control method for 3D printing according to an embodiment of the present disclosure.

Fig. 3 is a schematic flowchart illustrating a process of detecting a printing target printing component in an embodiment of the control method for 3D printing according to the present application.

Fig. 4 shows a schematic structural diagram of a bottom-exposure 3D printing apparatus in an embodiment, which is used for implementing the control method of 3D printing of the present application.

Fig. 5 is a flowchart illustrating a process of determining a target object according to an embodiment of the present invention.

Fig. 6 is a flowchart illustrating a process of denoising a current cured layer image according to an embodiment of the control method for 3D printing of the present application.

Fig. 7 is a schematic flowchart illustrating a process of determining a mapping relationship according to an embodiment of the control method for 3D printing.

Fig. 8 is a schematic flowchart illustrating a process of determining a target object according to an embodiment of the 3D printing control method of the present application.

Fig. 9 is a schematic flowchart illustrating a method for controlling 3D printing according to an embodiment of the present disclosure.

FIG. 10 is a schematic illustration of an embodiment in which a reference object is determined from the image shown in FIG. 1.

Fig. 11 is a flowchart illustrating a method for controlling 3D printing according to an embodiment of the present disclosure, wherein a matching result is generated based on a reference object and a target object.

Fig. 12 is a schematic diagram showing a reference slice image of a target printing member currently printed in the control method for 3D printing according to the present application in one embodiment.

FIG. 13 is a schematic illustration of a first layer slice image of a target printing component in one embodiment.

FIG. 14 is a schematic view of a projected image formed by projecting the target printing member of FIG. 13.

Fig. 15 is a flowchart illustrating step S110 in fig. 2 according to an embodiment.

Fig. 16 is a schematic diagram showing an initial mask image produced in an embodiment by the control method for 3D printing according to the present application.

Fig. 17a to 17c are schematic diagrams showing an outline of a target printing means after image processing in one embodiment.

Fig. 18 is a schematic diagram showing a mask image generated in an embodiment of a control method for 3D printing according to the present application.

Fig. 19 is a schematic view showing slice images of a plurality of target printing members currently in an embodiment, which is a control method of 3D printing of the present application.

Fig. 20 is a schematic diagram showing an actual projection image formed by masking the sliced image of the plurality of target printing members shown in fig. 19 with the mask image of fig. 18 to perform a print job in one embodiment of the control method for 3D printing according to the present application.

Fig. 21 shows a schematic diagram of a reference slice image of a target printing member currently printed in the control method for 3D printing of the present application in another embodiment.

Fig. 22 is a schematic diagram showing a mask image generated in another embodiment according to fig. 21 by the control method for 3D printing according to the present application.

Fig. 23 is a schematic view showing a slice image of a plurality of target printing members currently in another embodiment as a control method of 3D printing of the present application.

Fig. 24 is a schematic view showing an actual projection image formed by performing a printing job by masking the cut-out images of the plurality of target printing members shown in fig. 23 with the mask image of fig. 22 in another embodiment as a control method of 3D printing of the present application.

FIG. 25 shows a simplified block diagram of a control system for 3D printing according to the present application in one embodiment.

Fig. 26 shows a simplified block diagram of a control system for 3D printing according to the present application in another embodiment.

Fig. 27 shows a schematic structural diagram of a top-exposed 3D printing apparatus according to an embodiment of the present application.

FIG. 28 is a simplified block diagram of a computing device of the present application in one embodiment.

Detailed Description

The following description of the embodiments of the present application is provided for illustrative purposes, and other advantages and capabilities of the present application will become apparent to those skilled in the art from the present disclosure.

In the following description, reference is made to the accompanying drawings that describe several embodiments of the application. It is to be understood that other embodiments may be utilized and that changes in the module or unit composition, electrical, and operation may be made without departing from the spirit and scope of the present disclosure. The following detailed description is not to be taken in a limiting sense, and the scope of embodiments of the present application is defined only by the claims of the issued patent. The terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting of the application.

Although the terms first, second, etc. may be used herein in some instances to describe various elements, information, or parameters, these elements or parameters should not be limited by these terms. These terms are only used to distinguish one element or parameter from another element or parameter. For example, a first element could be termed a second element, and, similarly, a second element could be termed a first element, without departing from the scope of the various described embodiments. Both the first and second elements are described as one element, but they are not the same element unless the context clearly dictates otherwise. Depending on the context, for example, the word "if" as used herein may be interpreted as "at … …" or "when … …".

Also, as used herein, the singular forms "a," "an," and "the" are intended to include the plural forms as well, unless the context indicates otherwise. It will be further understood that the terms "comprises," "comprising," "includes" and/or "including," when used in this specification, specify the presence of stated features, steps, operations, elements, components, items, species, and/or groups, but do not preclude the presence, or addition of one or more other features, steps, operations, elements, components, species, and/or groups thereof. The terms "or" and/or "as used herein are to be construed as inclusive or meaning any one or any combination. Thus, "A, B or C" or "A, B and/or C" means "any of the following: a; b; c; a and B; a and C; b and C; A. b and C ". An exception to this definition will occur only when a combination of elements, functions, steps or operations are inherently mutually exclusive in some way.

Generally, a 3D printing apparatus includes a container, an energy radiation system, a Z-axis driving mechanism, a component platform, and a control device, and obtains a three-dimensional object (in the following description, the three-dimensional object is collectively referred to as a 3D printing component) such as a mold, a medical jig, a customized product, and the like by performing energy radiation on a photo-curable material to cure. After determining the structural parameters of the component model to be printed, generating a printing process which can realize layer-by-layer solidification by the component model through pretreatment and at least comprises layer height and slice images or scanning path slice data, then printing based on each slice data, and accumulating the solidified layers layer by layer to obtain the 3D printing component with a complete structure.

The energy radiation system is a surface projection based energy radiation system or a scanning radiation based energy radiation system. In a common 3D printing apparatus, such as a DLP (Digital Light processing) apparatus based on bottom-surface exposure, an energy radiation system thereof includes a projection device based on surface projection, which includes a DMD chip, a controller, a memory module, and the like. Wherein the storage module stores therein slice images for layering a 3D object model. And the DMD chip irradiates light sources corresponding to all pixels on the slice image to the bottom surface of the container after receiving a control signal of the controller. In fact, the mirror is composed of hundreds of thousands or even millions of micro mirrors, each micro mirror represents a pixel, and the projected image is composed of the pixels. The DMD chip may be simply described as a semiconductor photo switch and a micromirror plate corresponding to the pixel points, and the controller allows/prohibits each of the micromirrors by controlling each of the photo switches in the DMD chip to reflect light, thereby irradiating the corresponding slice image onto the photo-curable material through the transparent bottom of the container, so that the photo-curable material corresponding to the shape of the image is cured to obtain a pattern-cured layer.

In another or conventional SLA (Stereo lithography Apparatus), for bottom-surface exposure or top-surface exposure, the energy radiation system includes an energy radiation device based on scanning radiation, which includes a laser emitter, a lens set located on an outgoing light path of the laser emitter, and a vibrating mirror set located on an outgoing light side of the lens set, and a motor for controlling the vibrating mirror, and the like, wherein the laser emitter is controlled to adjust energy of an output laser beam, for example, the laser emitter is controlled to emit a laser beam with a preset power and stop emitting the laser beam, and further, the laser emitter is controlled to increase power of the laser beam and decrease power of the laser beam. The lens group is used for adjusting the focusing position of the laser beam, the galvanometer group is used for controllably scanning the laser beam in a two-dimensional space on the bottom surface or the top surface of the container, the photocuring material scanned by the laser beam is solidified into a corresponding pattern solidified layer, and the swing amplitude of the galvanometer group determines the scanning size of the SLA equipment.

In a further or more common LCD (Liquid Crystal Display, Liquid Crystal surface light source curing) device, for example, based on bottom exposure, the energy radiation system comprises an LCD Liquid Crystal screen light source arrangement. The LCD liquid crystal screen light source device comprises an LCD liquid crystal screen and a light source, wherein the LCD liquid crystal screen is positioned below the container, and the light source is arranged below the LCD liquid crystal screen in an aligned mode. A control chip in the LCD liquid crystal screen light source device projects a slice image of a slice to be printed to a printing surface through the LCD liquid crystal screen, and a pattern radiation surface provided by the LCD liquid crystal screen is utilized to solidify a material to be solidified in a container into a corresponding pattern solidified layer.

Furthermore, in some embodiments, the energy radiation system may further include a plurality of energy radiation devices for collectively irradiating the material to be cured within the container to obtain the pattern-cured layer.

The type of the energy radiation device is determined according to the type of the printing apparatus. The specific number of energy radiating means may be determined according to the required web size and may be configured to include, but is not limited to, 2, 3, 4, 5, 6, 7, 8, 9, 10 … …, etc. The position layout of the plurality of energy radiation devices can also be determined according to the actual requirement and the number of the energy radiation devices, for example, all the energy radiation devices are arranged side by side to form an elongated web, or are arranged in a plurality of rows and columns, and the like. For example, the energy radiation system may include 4 energy radiation devices, and the 4 energy radiation devices may be configured in a 2 × 2 (i.e., 2 rows and 2 columns) form.

In the printing process, each energy radiation device radiates energy to a printing reference surface according to the received slice image or sub-slice image when receiving a printing instruction, so that an optical radiation breadth corresponding to each slice image or sub-slice image is obtained on the printing reference surface. Each slice image or sub-slice image is obtained by processing the slice image of the 3D printing component, so that each energy radiation device can selectively solidify the material to be solidified on the printing reference surface after radiating energy to the printing reference surface according to the slice image or sub-slice image received by the energy radiation device, thereby obtaining a solidified layer corresponding to the slice image on the printing reference surface and forming the corresponding 3D printing component through accumulation of the solidified layer.

Conventionally, in a bottom exposure apparatus (such as a DLP or LCD apparatus), the member stage is suspended above a printing reference surface, and in a top exposure apparatus (such as a DLP or SLA apparatus), the member stage is suspended below the printing reference surface (generally referred to as a liquid surface of a resin bath) for attaching and accumulating a radiation-cured pattern cured layer. Typically, the material of the component platform is different from the photocurable material. The component platform is driven by a Z-axis driving mechanism in the 3D printing equipment to move along the Z-axis (vertical) direction so that the material to be solidified is filled between the component platform and the printing reference surface, so that an energy radiation system in the 3D printing equipment can irradiate the material to be solidified through energy radiation, and the irradiated material is solidified and accumulated and attached to the component platform. In order to accurately control the irradiation energy of each cured layer, the component platform and the attached 3D object part to be manufactured are moved to a position where the minimum distance between the component platform and the printing reference surface is equal to the layer thickness of the cured layer to be cured, and the component platform is driven by the Z-axis driving mechanism to ascend so as to separate the cured layer from the bottom of the container.

In a bottom exposure apparatus (such as a DLP or LCD apparatus), when the Z-axis driving mechanism moves the component stage down, it is usually for lowering the component stage or the patterned cured layer attached to the component stage to a space higher than a cured layer at the bottom of the container, so as to irradiate the light-curable material filled in the space. When the Z-axis driving mechanism drives the component platform to ascend, the solidified layer is usually separated from the bottom of the container.

And the control device is connected with the Z-axis driving mechanism and the energy radiation system and is used for controlling the Z-axis driving mechanism and the energy radiation system to print the 3D printing component. The control device may include: a memory unit, a processing unit, and an interface unit, etc.

The storage unit includes high speed random access memory and may also include non-volatile memory, such as one or more magnetic disk storage devices, flash memory devices, or other non-volatile solid state storage devices. In certain embodiments, the storage unit may also include memory remote from the one or more processors, such as network-attached memory accessed via RF circuitry or external ports and a communication network (not shown), which may be the internet, one or more intranets, Local Area Networks (LANs), wide area networks (WLANs), Storage Area Networks (SANs), etc., or a suitable combination thereof. The memory controller may control access to the memory by other components of the device, such as the CPU and peripheral interfaces.

The processing unit includes one or more general purpose microprocessors, one or more application specific processors (ASICs), one or more field programmable logic arrays (FPGAs), or any combination thereof. The processing unit is operatively coupled with memory and/or non-volatile storage. More specifically, the processor may execute instructions stored in the memory and/or the non-volatile storage device to perform operations in the computing device, such as generating image data and/or transmitting image data to an electronic display. For example, after the processing unit controls the Z-axis driving mechanism to lower the component platform to a position spaced from the bottom of the container, the processing unit transmits the slice image to the energy radiation system, and after the energy radiation system finishes image irradiation and carries out patterned curing on the light-cured material at the bottom of the container, the processing unit controls the Z-axis driving mechanism to drive the component platform to ascend so as to separate the corresponding patterned cured layer from the bottom of the container. On the other hand, the processing unit also calculates an operation parameter applied to the Z-axis drive mechanism in the separating operation at the time of separating. Taking the example that the Z-axis driving mechanism includes the driving motor, the faster the rotation speed of the driving motor is, the faster the separating operation and member platform is lifted, and conversely, the slower the rotation speed is, the slower the separating operation and member platform is lifted.

The interface unit comprises a plurality of interfaces, and each interface is respectively connected with the energy radiation system, the component platform and the Z-axis driving mechanism. Each interface is configured on the control device according to an actual data transmission protocol, and the processing unit is operatively coupled with each interface so that the control device can interact with the connecting energy radiation system, the component platform, and the Z-axis drive mechanism.

During printing, the control device controls the Z-axis driving mechanism and the energy radiation system to cure the photocuring layer by layer. The control device sends the slice images to the energy radiation system one by one according to a preset printing sequence, the slice images are irradiated to the transparent bottom or the top of the container by the energy radiation system, and the irradiated energy solidifies the light-cured material at the bottom or the top of the container into a corresponding pattern solidified layer. The control device is further configured to send a control instruction to the Z-axis driving mechanism at the irradiation gap, for example, taking a bottom-exposure-based 3D printing apparatus as an example, after the control device controls the exposure device to complete irradiation, the control device sends a control instruction of a rising direction and a rotating speed to the Z-axis driving mechanism, the Z-axis driving mechanism rises to a preset height from the bottom of the container based on the control instruction, and then the control device sends a control instruction including a falling direction and a rotating speed to the Z-axis driving mechanism, so that the Z-axis driving mechanism drives the component platform to move to the bottom of the container. The control device determines the spacing of the component platform relative to the container bottom by monitoring the movement of the Z-axis drive mechanism throughout the ascent and descent, and outputs a control command including a stop when the component platform reaches the corresponding spacing. The control device judges whether the 3D object model finishes the irradiation of all the slice images, if so, the printing is finished, and if not, the printing process is repeatedly executed until the printing is finished.

The container is used for containing the material to be solidified, and the material to be solidified comprises any liquid material which is easy to be solidified by light, and examples of the liquid material comprise: a photocurable resin liquid, or a resin liquid doped with a mixed material such as a powder or a color additive. The doped powder materials include, but are not limited to: ceramic powder, color additive powder, etc.

In a bottom-exposure based 3D printing apparatus, the container may be entirely transparent or only transparent at the bottom of the container, for example, the container is a glass container, and the container wall is attached with light absorbing paper (such as black film, black paper, etc.) so as to reduce the curing interference of the light-curing material due to light scattering during projection. A transparent flexible film (not shown) is laid on the bottom surface of the container for easy peeling.

As described in the background, in actual printing, each device or system associated with printing may be degraded or abnormal, or a distortion, a collapse, or the like of a cured layer in printing may be caused in accordance with an expected printing standard due to setting of parameters such as the radiation intensity of an energy radiation system, the drive control of a Z-axis drive mechanism, or even improper setting of property parameters of a printing member such as the member geometry. When the solidified layer has printing defects during printing, if the printing defects cannot be processed in time, the printing equipment can continue the subsequent printing process, this may result in a failure of the finished 3D printed member due to a defective printing of the cured layer, and extends unnecessary loss of printing time and printing cost, especially, when a plurality of 3D printing members are printed simultaneously in one printing process, if one or more 3D printing members having a printing defect cannot be processed in time, the printing apparatus continues the subsequent printing process, this may not only result in the failure of the finished 3D printing member or members with printing defects, but also result in the interference or contamination of other 3D printing members, the transparent flexible film laid on the bottom surface of the container, the photo-curing material, or the corresponding mechanism (e.g., Z-axis driving mechanism), etc. by the 3D printing member or members with printing defects. Therefore, it is necessary to monitor the printing process and process one or some 3D printing components when detecting that the printing defect exists in the one or some 3D printing components, so as to overcome the aforementioned various problems.

To facilitate the explanation of the specific implementations provided herein, the following terms to which this application relates are explained herein:

in any of the embodiments provided in the present application, the term "printing reference plane" (printing surface) is a curing position for receiving energy radiated by the energy radiation system to cure the printing material into a corresponding pattern cured layer according to the slice data; in general, in an embodiment of the DLP apparatus that exposes in the bottom, its printing reference surface is located at the bottom surface of the container (resin tank); in the case of a top-exposure SLA facility or DLP facility, for example, the printing reference surface thereof may be the liquid level of the printing material such as resin in the container; it will be appreciated that in other specific embodiments, such as those in which an LCD is the energy radiation system, the print datum is the level of the printing material, such as resin, within the container, the bottom of the container, or a level of the resin level.

In any embodiment provided in the present application, the 3D printing component is a three-dimensional object that is cured layer by radiating energy to a printing reference plane by the energy radiation system, and it should be noted that layer-by-layer curing of one or more three-dimensional objects can be simultaneously achieved on the printing reference plane, for example, when a plurality of three-dimensional object decorations can be simultaneously performed on a printing surface defined by a container (resin tank), the 3D printing component is a plurality of three-dimensional objects in the printing surface; accordingly, the control method of the present application may be a printing control method for printing a plurality of three-dimensional objects in a printing width. In the following description of the present application, the 3D printing means may also be referred to as a target printing means.

In any of the embodiments provided in the present application, the "current solidified layer image" may also be referred to as "solidified layer image at the current time", and is used to explain that the energy radiation system radiates energy to the photo-solidified material at the printing reference surface at the current time, and the photo-solidified material is solidified and formed and is captured by the capturing device; for example, in the embodiment of the DLP apparatus for bottom exposure, the image of the present cured layer is an image of a cured layer at the bottom of the container (resin tank) radiation-cured by a DLP light machine; for example, in a top-exposure SLA or DLP facility, the image of the cured layer at present is an image of a cured layer at the liquid level of the resin tank radiation-cured by an SLA laser or DLP light machine.

In any of the embodiments provided herein, the slice image is a sectional view within the same layer that is used to illustrate a three-dimensional model layering process (also referred to as a slicing process) on a 3D printed structure. Slice data may be obtained after the three-dimensional model is layered, which includes the complete 3D printed building block's layered processing method such as the layer height for each layer configuration and the layered (slice) pattern for each layer, i.e., the slice image described herein. The slice image is obtained by performing cross-sectional division in the Z-axis direction (i.e., in the height direction) based on the 3D printing member model in advance. A slice image outlined by the outline of the three-dimensional model of the 3D printed member is formed on the cross-sectional layer formed by each adjacent cross-sectional division, and in the case where the cross-sectional layer is sufficiently thin, the contour lines of the upper cross-sectional surface and the lower cross-sectional surface of the cross-sectional layer can be assumed to be identical. In general, for a 3D printing apparatus based on surface projection, each slice image needs to be described as a layered image. For a 3D printing device based on scanning illumination, each slice image is described by coordinate data on the scanning path.

The slicing data may be in any known Format, including but not limited to Standard Tessellation Language (STL) or stereolithography Contour (SLC) Format, Virtual Reality Modeling Language (VRML), Additive Manufacturing File (AMF) Format, Drawing Exchange Format (DXF), Polygon File Format (PLY) Format, or any other Format suitable for Computer-Aided Design (CAD).

In any of the embodiments provided herein, the slice image corresponding to the cured layer image is a slice image of all 3D printing members in the printing web at the printing reference plane at the height position corresponding to the cured layer; for example, when a plurality of printing members are provided in the printing surface (or the printing reference surface), the current solidified layer image may include solidified layer images of a plurality of actual printing members during printing, and the slice image corresponding to the current solidified layer image is a slice image corresponding to slice data of the plurality of actual printing members. The printing format is the maximum printable range, for example, in the case of an SLA device, the printing format is generally determined by a container of the printing device for containing printing materials; for DLP or LCD devices, the printing format is generally determined by the projectable range of the energy radiation system.

In any of the embodiments provided herein, the slice profiles are used to describe independent profiles in the slice images, for example, a closed circle profile is a slice profile, and two independent circle profiles are two slice profiles described herein; thus, any two slice profiles within the same slice image as defined herein are independent (no overlap). It should be understood that the slice profile is also a theoretical profile of the actual printed component area. For example, when a plurality of printing members are placed on the printing surface at the same time, the slice profiles of different printing members are independent profiles of course; alternatively, there may be a plurality of independent contours in the cross-sectional layer image at a certain height position for the same printing member. Referring to fig. 1, a schematic diagram of a printing range and a slice image corresponding to a cured layer in an embodiment of a control method for 3D printing according to the present application is shown. The outer layer rectangular frame line is the printing breadth range, and the slice image is a contour a, a contour b, a contour c, a contour d, a contour e, a contour f, a contour g and a contour h in the printing breadth; the outlines are independent of each other, that is, any one of the outline a, the outline b, the outline c, the outline d, the outline e, the outline f and the outline g can be regarded as a slice outline described in the present application, and the outline a, the outline b, the outline c, the outline d, the outline e, the outline f, the outline g and the outline h can be outlines formed by the same printing member or outlines formed by a plurality of printing members belonging to a printing width.

In any of the embodiments provided in the present application, the printing member profile is a cross-sectional profile for explaining that the printing member is described at the position of the cured layer in the current cured layer image. The current cured layer image is an image formed by capturing an actual printing environment by means of a capturing device, and therefore the range of the current cured layer image generally includes a printing format and a printing component in the printing format, and the contour of the printing component is obtained by processing (analyzing) the current cured layer image. The current solidified layer image is an image obtained by shooting that reflects the true form of the printing member, and therefore, in some embodiments, the current solidified layer image further includes, for example, a support structure configured for the printing member.

In any of the embodiments provided herein, the curing profile is an independent profile for explaining a profile belonging to the printing member in the current cured layer image, the printing member profile being formed by the energy radiation system obtaining the cured layer of the printing member from the slice image radiation energy, and therefore, the printing member profile has a correspondence with the slice profile of the slice image in an ideal state. Typically, the current solidified layer image is an image captured by a capturing device, and the solidified outline needs to be extracted from the current solidified layer image obtained by capturing; in an implementation, for example, the contour belonging to the printing member is determined from the current solidified layer image, as defined above, the printing member contour may include one or more individual contours, and each individual contour in the printing member contour obtained by image processing (analysis) based on the current solidified layer image is referred to as a solidified contour. The curing profile is also the actual printing member profile reflected by the camera. For example, when a plurality of printing members are simultaneously placed in the printing width of the printing reference surface, the curing profiles of the different printing members are of course independent profiles; alternatively, there may be multiple independent curing profiles in a cross-sectional layer image at a certain height position for the same printing member. The definition of independence between the solidification profiles can also be described herein with reference to the example shown in fig. 1 for the slicing profiles.

The application provides a control method for 3D printing in a first aspect, comprising the steps of: when detecting that at least one target printing component in a plurality of target printing components printed currently has a printing defect, acquiring reference slice images of the plurality of target printing components; performing image processing on a reference slice image of the target printing components corresponding to the at least one target printing component to obtain the outline of the at least one target printing component; generating a mask image from the profile of the at least one target printing member; wherein a region in the mask image corresponding to a contour of the at least one target printing member is an exposure-inhibited region; performing a masking operation on the slice images of the plurality of target printing members using the mask image to perform a print job.

In the 3D printing control method provided by the present application, when it is detected that at least one target printing member has a printing defect during a printing process, an outline of the at least one target printing member is acquired, and a mask image is generated according to the outline, where an area in the mask image corresponding to the outline of the at least one target printing member is an exposure prohibition area, and a printing job is executed by using the mask image, so that the at least one target printing member having the printing defect is no longer continuously printed but other normal target printing members can continue to print, the printing process is not interrupted, the at least one target printing member having the printing defect can be prevented from interfering with or contaminating other target printing members, photocurable materials, films, or corresponding mechanisms during the printing process, and time cost and material cost can be saved.

Please refer to fig. 2, which is a flowchart illustrating a 3D printing control method according to an embodiment of the present disclosure.

In step S100, when it is detected that at least one of the plurality of target printing members currently printed has a print defect, reference slice images of the plurality of target printing members are acquired.

In certain embodiments of the present application, multiple target-printed components may be printed at a single time on a component platform using a 3D printing device. In actual printing, each device or system may be degraded or abnormal in association with printing, or improper setting of parameters such as the radiation intensity of the energy radiation system, the drive control of the Z-axis drive mechanism, or even the property parameters of the target printing member such as the member geometry may cause distortion, collapse, or the like of the solidified layer during printing to be out of the expected printing standard. For this reason, it is necessary to detect the target printing member or members having the print defect. The control method for 3D printing further comprises the step of monitoring the printing process to detect whether printing defects exist in a plurality of target printing components which are printed currently.

Referring to fig. 3, a schematic flow chart illustrating a process of detecting a printed target printing component according to an embodiment of the 3D printing control method of the present application is shown.

In step S101, current cured layer images of a plurality of target printing members currently printed and slice images corresponding to the current cured layer images are acquired; wherein the slice image comprises one or more slice contours.

It should be understood that the detection of the printed target printing member in the present application is realized by image processing (analysis) of the cured layer and the theoretical cured layer of the currently printed target printing member, and therefore, in an implementation, the current cured layer image of the currently printed target printing member and the slice image corresponding to the current cured layer image are acquired. It should be understood that the printing process is to irradiate energy based on the slice image by the energy irradiation system to cure the printing material into the corresponding cured layer pattern at the printing reference surface, and thus, the slice image corresponding to the current cured layer image is the slice image used by the energy irradiation system to irradiate energy to obtain the slice image of the current cured layer. The target to be detected here is a target printing means currently still in the print job, and may not include a target printing means not in the print job, or a target printing means that has been suspended from printing or cancelled from printing. The current solidified layer image is obtained by, for example, capturing an image of the inside of the molding chamber by a capturing device during printing. The forming chamber includes a container in the printing apparatus and is typically used to isolate the external environment to form a print job space.

The photographing devices include, but are not limited to: a camera, a video camera, an image pickup module in which a lens and a CCD are integrated, an image pickup module in which a lens and a CMOS are integrated, or the like. Wherein the photographing device may be installed at a bottom of the container or an open upper side of the container, for example, according to a structure of the 3D printing apparatus. For example, the 3D printing apparatus is a top-surface exposed 3D printing apparatus, and the photographing device is installed on an upper side of the opening of the container and photographs the inspection image facing the opening of the container.

For another example, please refer to fig. 4, which shows a schematic structural diagram of a 3D printing apparatus for bottom exposure, which is used to implement the control method of 3D printing according to the present application. Wherein the printing apparatus is further provided with a camera 21, said camera 21 being mounted outside the container 11. In some specific examples, the camera 21 is mounted at the bottom of the container and does not affect the position where the energy radiation system 14 performs the curing operation. For example, the side bottom of the container 11, near which the photographing device 21 may be supported, is also of a transparent structure. As another example, the camera 21 is supported below the transparent bottom surface of the container and does not affect the position where the energy radiation system 14 irradiates energy. The photographing device 21 photographs facing the container 11. In the embodiment shown in fig. 4, in order to be able to satisfy the image acquisition of the cured layer at the printing reference plane of the 3D printing apparatus, the photographing device 21 may be installed below the bottom of the container 11.

The position where the shooting device is installed can be determined based on the need of acquiring the current solidified layer image, and in some examples, the shooting device can be installed towards a printing reference surface at a certain inclination, so that the utilization rate of the shooting format of the shooting device is improved.

The photographing device for acquiring the solidified layer image may be further configured to be connected to a device or apparatus for performing the subsequent steps in the control method, and the specific connection may be a wired connection or a wireless connection (communication connection). For example, an electronic apparatus that can perform digital calculation and logical operation based on the cured layer image, which may be connected to the photographing device through a data line, includes, but is not limited to: embedded electronic devices, computer devices including one or more processors, single-chip computers including processors, and the like. In an implementation, the means for acquiring the reference object in the solidified layer image may share an electronic device with the control means of the printing apparatus or be configured separately, and data communication between the two may be realized through a data line or a program interface.

In some specific examples, the photographing device may be controlled by a control device in the 3D printing apparatus to photograph the opportunity. The control device can be connected with the Z-axis driving mechanism and the energy radiation system and is used for coordinating and controlling the Z-axis driving mechanism and the energy radiation system to execute layer-by-layer curing operation. When the control device controls the energy radiation system to obtain a solidified layer and does not control the Z-axis driving mechanism to strip, or when the control device controls the Z-axis driving mechanism to move the component platform to be away from the printing reference surface of the container at a certain interval, a photographing instruction is sent to the photographing device, and the photographing device photographs images in the container to obtain images of the current solidified layer corresponding to the target printing components. For example, the control means issues a photographing instruction to the photographing means when it is detected that the data irradiation of the slice image is completed. For another example, when the control device controls the Z-axis driving mechanism to move to a certain distance from the printing reference surface of the container, a photographing instruction is sent to the photographing device.

It should be noted that, in some embodiments, the shooting range that can be shot by a single shooting device corresponds to the radiation range of a single energy radiation device in the energy radiation system, that is, if the energy radiation system includes a plurality of energy radiation devices, the 3D printing apparatus may configure a corresponding number of multiple shooting devices. For example, the energy radiation system may include 4 energy radiation devices, and the 4 energy radiation devices may be configured in a 2 × 2 (i.e., 2 rows and 2 columns), and then the 3D printing apparatus may be configured with 4 cameras, and the 4 cameras may be configured in a 2 × 2 (i.e., 2 rows and 2 columns). In some embodiments, the shooting range that can be shot by a single shooting device corresponds to the radiation ranges of at least two energy radiation devices in the energy radiation system, for example, the energy radiation system may include 4 energy radiation devices, the 4 energy radiation devices may be configured in a 2 × 2 (i.e., 2 rows and 2 columns), the 3D printing apparatus may be configured with 1 shooting device, the radiation ranges of the four energy radiation devices are covered by the shooting range of the one shooting device, or the 3D printing apparatus may be configured with 2 shooting devices, wherein the shooting range of each shooting device covers the radiation ranges of the two energy radiation devices.

In addition, the sending time of the photographing instruction is only an example and is not a limitation to the present application. The purpose of issuing the photographing instruction is to control the photographing device to take an image including the contour of the solidified layer closest to the current solidified layer and provide for acquiring the target object. Meanwhile, the device or the functional module for controlling the photographing time of the photographing device is not limited by the control device of the printing equipment.

The slice image is acquired, for example, by acquiring a slice image in slice data corresponding to the current solidified layer image, and typically, the slice data may be stored, for example, in a printing apparatus or in another apparatus having a memory or a storage medium connected to the printing apparatus, whereby an energy radiation system of the printing apparatus acquires the slice image to radiate energy based on the slice image. In an implementation, the stored slice data or slice images in the slice data may be transmitted to a functional module or device or apparatus for executing the determination of the reference image in the slice image, for example, by data transmission implemented by a wired connection or a wireless connection. Wherein the slice image is described by pixel data of the image or vector data indicating the energy beam scan, for example.

After the current solidified layer image and the slice image corresponding to the current solidified layer image are acquired, in step S102, a target object is determined from the current solidified layer image, and a reference object is determined from the slice image.

It should be understood that the current solidified layer image is obtained by shooting the forming chamber in the actual printing environment, and generally, the image range of the current solidified layer image at least includes the printing breadth of the container, or may include the container and the part in the container such as the whole component platform in the shooting direction. The target object is obtained by processing one or more curing contours in the current cured layer image, that is, the target object is obtained by determining curing contours belonging to the contour of the printing member from the cured layer image.

In general, the cured layer image is represented as an image in which the shooting range size and pixels are determined, and the outline of the printing member in the cured layer image is formed based on the difference between the gradation value (again, RGB value, R value, G value, B value, YUV value) at the pixel point corresponding to the printing member and the gradation value (again, RGB value, R value, G value, B value, YUV value) at the pixel point outside the printing member, for example, the printing material that is not cured.

Here, the present application also provides an implementation of how to obtain the curing profile from the current curing layer image, so as to obtain a more accurate matching result between the reference object and the target object.

In step S102, a target object is determined from the current solidified layer image, and a reference object is determined from the slice image, and in some embodiments, the determination of the target object from the current solidified layer image includes the steps of:

please refer to fig. 5, which is a flowchart illustrating a process of determining a target object according to an embodiment of the 3D printing control method of the present application.

In step S1021, denoising the current cured layer image to obtain a target printing member outline image;

in step S1022, a target object is determined in the target printing member outline image.

Generally, when the image capturing device is used for capturing an image in the forming chamber, the image range at least includes a printing format, the current solidified layer image may further include a container edge and other components outside the printing format area, and in this state, the contour in the current solidified layer image may include other contours than the contour of the target printing component; meanwhile, the image of the non-target printing component in the printing web may also interfere with the determination of the contour of the target printing component, or the contour of the target printing component in the current solidified layer image is not clear due to the limitation of the imaging quality of the shooting device, and the like. Accordingly, the current cured layer image is subjected to noise removal processing in step S1021 to obtain a target printing member outline image. For example, after the current solidified layer image is obtained, the functional module performing step 1021 is a module configured in a control device of the printing apparatus or other apparatuses associated with the control device.

Referring to fig. 6, a flowchart illustrating a process of denoising a current cured layer image according to an embodiment of the control method for 3D printing of the present application is shown. In some embodiments, the means for de-noising the current solidified layer image comprises the steps of:

in step S10211, a printing background image in the actual printing environment is acquired, the printing background image including a picture inside the molding room taken before curing is started.

The printing background image is an image captured by the imaging device into the molding chamber before curing is not started, for example, in the case of a top-exposure printing apparatus, the printing background image is an image captured by the imaging device from the bottom of the container when the curing layer is not attached to the member platform, and in the case of a top-exposure printing apparatus, the printing background image is an image captured by the imaging device from above the printing reference surface when the curing layer is not attached to the member platform. The printing background image can be used for determining an image corresponding to an area outside the target printing component in the curing process, and can also be understood as a gray value or an RGB value, an R value, a G value, a B value, a YUV value and the like corresponding to each pixel position of the area outside the target printing component.

In actual printing, the component platform is used to accumulate the layer-by-layer solidified layers, which may include the contours formed by the component platform when the current solidified layer is photographed in the molding chamber. The plane of the component platform is generally porous, while the structural requirements of the component platform itself, which is generally a non-transparent material, may cause disturbances in determining the contour of the target printed component in the current cured layer image. Accordingly, the present application also provides the following embodiments.

In certain implementations, the step of acquiring the print background image includes: the distance between a component platform and a shooting device in the printing equipment is determined so that the component platform in an image in a forming chamber acquired by the shooting device is in a fuzzy state. When the component platform is in a fuzzy state (blurring state) in the image acquired by the shooting device, the interference of the contour formed by the component platform on the background correction of the current solidified layer can be avoided or reduced.

In implementations, determining a distance between the component platform and the camera may be based on specific parameters in the printing environment; for example, when the printing apparatus is a bottom exposure apparatus, the camera is disposed at the bottom of the container for acquiring the printing reference plane image, the camera can be positioned at an installation position on the 3D printing apparatus before shipment, for example, at a fixed position away from the bottom of the container by a preset distance, and the distance between the component platform and the camera can be adjusted by adjusting the position of the component platform. Meanwhile, the definition of the component platform in the image acquired by the shooting device is determined, and is also related to the material property in the printing environment, for example, when the component platform is driven to move by the Z-axis driving mechanism, the height of the printing material filled between the component platform and the printing reference surface is changed, and the property of the printing material, such as material transparency, affects the imaging effect of the component platform after being shot.

In certain embodiments, the manner of determining the distance between the component platform and the camera comprises at least one of:

in one embodiment, the component platform is adjusted outside the depth of field of the camera when the transparency of the printed material is determined to be above a preset threshold. When the printing material in the container is a transparent material (that is, the transparency is above a preset threshold), the higher the transparency of the printing material is, the less the printing material between the common printing reference surface and the component platform affects the image presented by the component platform, and the preset threshold can be customized.

It will be appreciated that if the camera is mounted at a distance from the container, for example, then the Depth of Field (Depth of Field) corresponding to the camera may be determined, i.e., the range of subject front-to-back distances measured by the front edge of the camera's lens or other imager to enable clear images to be taken. And moving the component platform to the outside of the depth of field of the shooting device, so that the component platform image acquired by the shooting device is pasty.

In one implementation scenario, during the layer-by-layer curing process, the shooting device needs to acquire the image of the current cured layer at the printing reference surface, in order to acquire the image of the target printing component, the printing reference surface is set to be within the depth of field of the shooting device, and accordingly, when the printing background image is acquired, the component platform can be moved away from the printing reference surface to be outside the depth of field of the shooting device.

In one embodiment, when the transparency of the printing material is determined to be smaller than the preset threshold, the distance between the component platform and the printing reference surface is adjusted to make the component platform in the image in the forming chamber acquired by the shooting device be in a fuzzy state.

When the transparency of the printing material is low, the printing material filled between the component platform and the printing reference surface can influence the imaging effect of the component platform in the shooting device, in this state, the component platform can be moved to a position beyond the depth of field of the shooting device to obtain a fuzzy imaging effect, and the printing material can be filled in the component platform by adjusting the distance between the component platform and the printing reference surface, so that the component platform image obtained by the shooting device is in a fuzzy state.

After the printing background image is obtained, in step S10212, the current cured layer image is background-corrected based on the printing background image to implement a denoising process.

The printing background image can be used for characterizing other areas except the target printing component in the current solidified layer image, namely, the target printing component outline can be determined from the current solidified layer image in an assisting manner.

In some embodiments, the means for background rectifying the current cured layer image based on the printing background image includes any one of:

in one implementation, the grayscale value of the printing background image at each pixel point is subtracted from the grayscale value of the current cured layer image at each pixel point.

Generally, after the position of the shooting device relative to the container is determined, the position of the shooting device is not changed when an image is shot for each solidified layer in the process of printing the solidified layer by layer; the image in the area outside the target printing member and the member platform tends to be the same within the shooting range of the shooting device, and the implementation of making the member platform in a fuzzy state is provided in the foregoing example, so that by subtracting the gray value of the printing background image at each pixel point from the gray value of the current cured layer image at each pixel point, a clearer target printing member contour can be obtained, that is, the background correction of the current cured layer image is realized.

In the process, the overlapped image in the current solidified layer image and the printing background image can be denoised, for example, the gray values at the same pixel position are subtracted, the overall gray value of the image outside the target printing component area in the previous solidified layer image is greatly reduced, and the denoising of the contour of the target printing component is realized.

In yet another implementation, the RGB values of the printing background image at each pixel point are subtracted from the RGB values of the current solidified layer image at each pixel point.

It should be understood that the current solidified layer image and the printing background image at each pixel position can also be represented by other color data, such as RGB values, and in a specific implementation, the current solidified layer image and the printing background image represented by gray values can be subtracted by referring to the above description; it should be understood that it is only necessary to make the current solidified layer image and the printing background image be characterized by the same type of color or gray scale attribute at each pixel position, and for example, the R value, G value, B value, and YUV value of the current solidified layer image and the printing background image at each pixel position may also be subtracted.

Considering that the current solidified layer image and the printing background image are both obtained by the shooting device, and whether the reflection of the current solidified layer image and the actual printing background image is accurate is also influenced by the shooting device, the shooting environment, the shooting time and other factors, the present application further provides the following embodiments to explain how to obtain the current solidified layer image and the printing background image.

In some embodiments, acquiring the current solidified layer image comprises:

in one implementation, a single image is taken of the inside of the molding chamber to determine the current solidified layer image when the current solidified layer is proximate to or located at a print reference surface in the molding chamber. The printing reference surface in the forming chamber is the printing reference surface in the container.

The current solidified layer image is used for determining the form of the current solidified layer in printing, and each solidified layer is formed by solidifying the printing material by receiving radiation energy at the printing reference surface; for a bottom-exposed 3D printing device, the printing reference surface is the bottom surface of the container, and for a top-exposed 3D printing device, the printing reference surface is, for example, the upper surface or the free surface of the printing material in the container; in implementations, the current solidified layer image may be captured, for example, when the current solidified layer is adhered to the bottom surface of the container or on the upper surface of the printed material; in some embodiments, the Z-axis driving mechanism may further move the component platform to a position close to the printing reference surface to acquire the image of the current cured layer, for example, in a scene where the printing material is transparent resin, the component platform may be driven to move so that the current cured layer is higher than the printing reference surface to acquire the image of the current cured layer of the target printing component.

In another implementation, when the current solidified layer is adjacent to or located in the printing reference surface of the forming chamber, a plurality of images in the forming chamber are shot, and the average noise reduction is carried out on the plurality of images to obtain the image of the current solidified layer.

In this example, for the same current solidified layer, images of multiple current solidified layers can be acquired and noise reduction can be performed on the multiple images in an averaging manner to obtain an image of the current solidified layer for obtaining a subsequent target object, so that noise interference of a single image on an image formed due to shooting timing or environmental factors can be avoided or reduced, and for example, an effect of eliminating part of mixed points in the image can be obtained. The average noise reduction is, for example, averaging the color data or the gray data of a plurality of images at the same pixel position.

In some embodiments, the obtaining of the print background image comprises:

in one implementation, a photograph of the inside of the molding chamber is taken before curing begins to determine a print background image. Here, the manner of capturing the image in the forming chamber to determine the printing background image may refer to the foregoing embodiments, for example, the component platform is moved to a position where the component platform is in a fuzzy state in the image captured by the capturing device, and details thereof are not repeated herein.

In another implementation, a plurality of images within the molding chamber are taken before curing begins and average noise reduction is performed on the plurality of images to obtain a printed background image.

The method comprises the steps of obtaining a plurality of images in a forming chamber in the printing environment before solidification, reducing noise by an averaging method, and obtaining a printing background image which can be used for performing background correction on the image of the current solidified layer, so that noise interference of a single image on the background image due to shooting time or environmental factors and the like can be avoided or reduced, and the effect of eliminating part of miscellaneous points in the background image can be obtained. The average noise reduction is, for example, averaging the color data or the gray data of a plurality of images at the same pixel position.

In some embodiments, the means for de-noising the current solidified layer image comprises: and performing at least one of filtering, binarization and erosion on the current solidified layer image to improve the definition of the contour of the target printing component in the current solidified layer image.

The present application provides a way of denoising the image of the current solidified layer by printing the background image in the foregoing example, where the way of denoising the image of the current solidified layer may also be at least one of filtering, binarizing and corroding the image, and meanwhile, the processing of filtering and the like of the image is not mutually exclusive with the background correction based on the printing background image, for example, in an embodiment, the background correction may be performed on the image of the current solidified layer based on the printing background image, and the filtering, binarizing and the like may be performed on the corrected image of the current solidified layer. Of course, the specific processing manner of the image of the current solidified layer is not limited to the foregoing example, and it should be understood that the filtering, binarization, and erosion processes are all performed on the image to obtain a clearer target printing member contour, and therefore, those skilled in the art may also adopt other image processing manners to obtain the target printing member contour, such as image enhancement, hough transform, and the like.

After determining the current solidified layer image for acquiring the target object, the reference object and the target object can be compared for determining the printing quality of the current solidified layer by analyzing the current solidified layer image to determine the target object therein and determining the reference object from the slice image corresponding to the current solidified layer image.

With continuing reference to fig. 3, as shown, in step S102, the target object is determined from the current solidified layer image, and the reference object is determined from the slice image.

As in the previous examples, the current solidified layer image is captured by the capturing device, and the slice image is a slice image in slice data for irradiating energy by the energy irradiation system in accordance with the pattern shape thereof, and thus, the current solidified layer image is an image characterized by an optical coordinate system determined by the capturing device, and the slice image is an image adapted to the projection coordinate system of the energy irradiation system. The present application also provides embodiments for converting the current solidified layer image and the slice image to the same coordinate system to obtain a more accurate comparison of the target object with the reference object.

In some embodiments, the method for controlling 3D printing further includes a step of performing perspective transformation processing on the current solidified layer image or the slice image to obtain a target object and a reference object characterized by the same coordinate system. The same coordinate system is, for example, a projection coordinate system of an energy radiation system in the printing apparatus or an optical coordinate system of the photographing device. Of course, in other implementations, the current solidified layer image and the slice image may be converted to the same other coordinate system.

In the process of performing perspective transformation on the current solidified layer image or the slice image, a mapping relationship between the current solidified layer image and the slice image needs to be determined, so that the coordinate system of the current solidified layer image and the slice image can be unified by performing perspective transformation on either one of the current solidified layer image and the slice image. In other implementations, the projection relationship between the optical coordinate system and the projection coordinate system corresponding to the current solidified layer image and the slice image and the third coordinate system can be determined separately, so as to transform the current solidified layer image and the slice image into the representation in the third coordinate system in a perspective manner.

Please refer to fig. 7, which is a flowchart illustrating a process of determining a mapping relationship according to an embodiment of the present invention.

In some embodiments, the same coordinate system is a projection coordinate system of an energy radiation system in the printing apparatus or an optical coordinate system of a shooting device, and the determining of the mapping relationship by determining the mapping relationship between the current solidified layer image and the slice image to perform perspective transformation processing on the current solidified layer image or the slice image comprises the following steps:

projecting a plurality of calibration points on the printing reference surface and recording projection coordinates of the plurality of calibration points in a projection coordinate system of the energy radiation system in step S1021;

in step S1022, the photographing device is made to acquire an image of the printing reference surface to determine image coordinates of the plurality of calibration points in the optical coordinate system of the photographing device;

in step S1023, a mapping relationship between the current solidified layer image and the slice image is calculated and determined based on the projection coordinates and the imagery coordinates.

Based on that the energy radiation system projects (projects) a series of calibration points on the printing reference surface, and the projection coordinates of the calibration points projected by the energy radiation system under the projection coordinate system are prestored, the shooting device shoots and acquires the image of the calibration points projected by the energy radiation system on the printing reference surface, and then the relationship between the projection coordinate system of the energy radiation system and the optical coordinate system imaged by the shooting device can be determined.

It should be understood that when the calibration point is projected (projected) on the printing reference surface, the projection coordinates of the energy radiation system for projecting the calibration point can be obtained, for example, when the calculation of the mapping relation is performed by a processing module having a calculation capability, the projection coordinates of the energy radiation system for projecting the calibration point can be transmitted to the processing module; the method comprises the steps that a shooting device is made to obtain an image of a printing reference surface provided with a plurality of calibration points, and coordinates of the calibration points in an optical coordinate system in an image formed in the shooting device can be calculated based on the obtained image; thus, the image coordinates of the calibration point in the projection coordinate system of the energy radiation system and the image coordinates in the optical coordinate system of the shooting device are obtained, and the mapping relation between the projection coordinate system and the optical coordinate system can be calculated and obtained based on the projection coordinates and the image coordinates. The mapping relationship is, for example, a matrix obtained based on the projection coordinates compared with the image coordinates.

It should be understood that the calibration points are not points in a mathematical sense, for example, a graph with a smaller area relative to a printed format is used, and the calibration points are set to be operations commonly used in 3D printing, which is not described herein again.

In some implementations, to ensure the imaging effect of the calibration point, a flat diffuse reflection layer may be disposed on the component platform, for example, a piece of white paper may be laid on the component platform, so as to determine that the calibration point can be captured by the camera. Meanwhile, the position of the component platform can be adjusted to make the image of the index point highly consistent with the image of the cured layer in the subsequent printing, so that the mapping relation adopted when any one of the current cured layer image and the slice image is subjected to perspective transformation in the printing is correct.

The number and the position of the calibration points are not limited in this application, and it should be noted that, in order to calculate the mapping relationship, the calibration points should form a plane, so at least three calibration points capable of determining a plane are usually set.

The position of the index point may also affect the accuracy of a mapping relationship calculated based on the index point or the accuracy of the projected image of the energy radiation system, and in some embodiments, the manner of determining the position of the plurality of index points projected on the printing reference plane includes at least one of:

determining a plurality of calibration point positions projected on a printing reference surface based on the relation between the calibration point positions and the precision of the calibration point image projected by the energy radiation system;

and determining a plurality of calibration point positions projected on the printing reference surface based on the relationship between the calibration point positions and the calculation accuracy of the mapping relationship.

Generally, the span (distance) between the calibration points is increased, and the relative error of the calculation mapping relationship can be correspondingly reduced, so that the calculation precision can be improved; on the other hand, the projected image of the energy radiation system has the problems of image edge blurring, image deformation and the like caused by edge energy loss, and the image blurring and the image deformation are usually more obvious near the edge of the printed format, so that calibration points need to be avoided from being arranged at the edge of the printed format for controlling the projected image accuracy. In one example, the calibration points of the present application are, for example, four points located at four corners of the printing reference surface, and each calibration point is set to have a certain preset distance from the boundary of the printing reference surface; thus avoiding or reducing image distortion of the index points while maximizing the distance between the index points.

In certain embodiments, the control method for 3D printing of the present application further includes a step of determining an ROI region of the current solidified layer image to determine the target object in the ROI region of the current solidified layer image.

In some scenarios, the current solidified layer image acquired by the photographing device includes, in addition to the printing reference, other regions other than the printing reference, such as a device outside the container or an external environment image, for which, the amount Of calculation can be reduced by extracting a Region Of Interest (ROI) from the current solidified layer image to determine the target object in the ROI Region in the subsequent processing. For example, in one embodiment, to reduce the amount of processing computation on the image, after the current solidified layer image (or the current solidified layer image that has been background corrected) is acquired, an ROI region is taken on the image to define its range as a region useful for the contour of the target printing member, and then the target object is determined in the ROI region.

The ROI region should be set to include at least the outline of the target printing component and the region that is not related to the target printing component as far as possible, and in one implementation scenario, the ROI region is a region of the printing reference surface, or, in order to ensure that the ROI region includes at least the printing reference surface, the ROI region may be set to be larger than the printing surface region and its boundary is spaced from the boundary of the printing surface. The functional module for performing the determination of the ROI area for the current solidified layer image is, for example, an electronic device associated with the photographing apparatus, or a functional module in control software configured for the control apparatus, or a functional module configured in another device associated with the printing apparatus.

After determining the current solidified layer image and the corresponding slice image, a target object and a reference object are respectively determined therefrom. As previously defined, the slice image is one or more slice profiles of all target printing members within the printing reference plane at corresponding height positions, which may be determined for the height data in the slice data; the current solidified layer image is an image of a solidified layer obtained for the energy radiation system to radiate energy to solidify the printing material according to the slice image, and accordingly, includes one or more slice outlines.

In an actual printing scene, the current solidified layer image is a reflection of the image acquired by the shooting device on the current solidified layer, so that the current solidified layer image cannot completely reflect the real form of the current solidified layer due to limitations caused by factors such as the precision of the shooting device, the shooting environment and the like, and therefore, misjudgment may be caused on the printing quality judgment of the subsequent solidified layer so as to influence the control of the printing process.

The present application provides an embodiment of determining a target object in a current solidified layer image and determining a reference object in a slice image to determine the printing quality of the current solidified layer based on the comparison between the target object and the reference object, so that the calculation amount of image contrast and the misjudgment of a matching result can be effectively reduced, and the method is beneficial to actual production.

With continuing reference to fig. 3, in step S102, a target object is determined from the current solidified layer image, and a reference object is determined from the slice image; wherein the target object is obtained by processing one or more curing contours in the current curing layer image, and the reference object is obtained by processing one or more slice contours included in the slice image.

In some embodiments, processing the one or more cured profiles comprises: judging one or more curing profiles and determining the deletion operation of the curing profiles based on the judgment result; processing the one or more slice profiles includes: one or more slice contours are judged and a pruning operation for the slice contours is determined based on the judgment result.

In the embodiments provided herein, one or more curing contours in the current cured layer image are geometry-independent curing contours, and the deletion operation described herein determines whether to delete a curing contour by determining for each curing contour; the present application provides an embodiment of denoising an image of a current solidified layer in the foregoing example, and in general, denoising an image also deletes details in the image (i.e., details of noise); it should be understood that the deletion process described herein is different from the deletion of image details in the foregoing de-noising process, and the cured profile is a target printing member profile that needs to be retained in the image processing in the preceding stage; the deletion processing is to determine the deletion operation of the solidified contour for subsequent matching based on the characteristics of the solidified contour, and is not to delete noise for improving definition and the like in image denoising.

One or more slice outlines in the slice image are slice outlines independent of geometrical morphology, and the deletion operation on the slice outlines is to judge whether the slice outlines are deleted or not by judging each slice outline. Generally, the slice image is a theoretical image, i.e. the image itself meets the definition requirement, and the present application provides an embodiment of processing the slice image to obtain the reference object, thereby improving the accuracy of the matching result of the target object and the reference object.

Please refer to fig. 8, which is a flowchart illustrating a process of determining a target object according to an embodiment of the present invention.

In some embodiments, in step S102, determining the target object comprises:

in step S1026, one or more curing profiles included in the target printing member profile are determined in the current curing layer image.

After the image in the molding chamber is captured by the capturing device to obtain the image of the current cured layer, the contour of the target printing member is determined therefrom, and generally, the contour of the target printing member can be formed by the gray value difference or the color value difference between the region of the target printing member and the other region in the printing reference plane. Here, the manner of determining the target printing member profile may refer to the implementation manner provided in the foregoing embodiments of the present application, and is not described herein again.

In step S1027, it is determined whether the morphology of each cured profile meets a preset specification.

In some embodiments, when the contour in the slice image is a fine contour or a complex contour, there may be a problem that the fine contour cannot be obtained or is recognized incorrectly after being imaged in the current solidified layer contour formed by photographing the current solidified layer, so the present application provides an embodiment for determining whether each solidified contour meets the preset specification.

In some scenarios, when the target printing component is a geometric structure to be printed with the support structure as an aid, a cross-sectional image of the support structure corresponding to the layering height of the current cured layer may be further included in the current cured layer image; generally, in order to perform a supporting function and to facilitate removal of the arrangement in the form of a column, a net or a sheet, the corresponding cross-sectional image presents a fine, elongated profile or a scattered plurality of profiles, and thus tends to create disturbances in the current cured layer image, such as: the support structure cannot be represented as a real shape due to the limitation of the imaging accuracy of the photographing, a plurality of scattered contours are represented as one continuous contour or non-closed contour in the current solidified layer image or cannot be photographed, and the like. Therefore, the support structure influences the real form of the target printing component form in the current solidified layer image, and the image capable of better reflecting the real form of the target printing component can be obtained by judging the solidified profile according to the preset specification. In embodiments where the target printing member requires support structure to assist in printing, the curing profile described herein also includes the profile that the support structure assumes in the current cured layer image.

In the existing monitoring mode of the printing process, a solidified layer image is generally compared with a slice image to determine whether printing distortion exists or not, the present application provides that the current solidified layer image is processed in advance, solidification outlines are defined to determine a target object for comparison with the slice image, and then comparison with a reference object can be carried out according to the target object so as to realize printing control. The calculation amount required for determining the printing quality of the current solidified layer image can be effectively reduced by defining the characteristics of the current solidified layer image to obtain the target object, the accuracy of judging the printing quality can be effectively improved, and the printing control can be effectively realized.

The predetermined specification may be determined according to the requirement for a targetable object, for example, when the target object is to be set to the contour of the target printing member itself without including the contour of the support structure, the predetermined specification may be determined according to the contour characteristics of the support structure to recognize the contour formed by the support structure in the curing contour of the current cured layer image. The preset specification is used for acquiring (or defining) the characteristics of the curing profile and detecting the curing profile according to the characteristics to form a judgment result, so that the specific characteristic selection mode can be customized based on the requirement of the target object. The target object is used for comparing with the reference object to determine the printing quality of the current solidified layer, and controlling the printing job based on the target object, and correspondingly, the target object is used for reflecting the printing quality of the current solidified layer, and the corresponding preset specification can be configured according to the definition mode of the target object.

In certain embodiments, the predetermined specification is determined by at least one of profile size, profile area, profile geometry, profile aspect ratio, and profile perimeter to area ratio.

That is, in some embodiments, at least one of the profile size, the profile area, the profile geometry, the profile aspect ratio, and the profile perimeter-to-area ratio of the curing profile may be determined as a characteristic of the curing profile, and each curing profile may be determined according to the determined characteristic to determine the pruning operation on the curing profile.

The outline geometry is a geometric figure shape of the outline, such as a circle, a square, a star and the like; in some examples, the profile geometry also includes the morphology of the profile lines identified as open-loop profiles, which are typically formed due to algorithm errors, etc., and in embodiments, the cured profiles identified as open-loop profiles may be considered out of specification.

The contour dimension can be used for determining the geometric figure of the contour and the dimension of the geometric figure, such as the values of parameters of length, width, radius and the like of the contour.

In some examples, the deletion operation on the contour may be determined based on the contour area, for example, when the area of the cured contour is smaller than a certain threshold, the cured contour with too small area is easy to be wrong in the identification, i.e. the cured contour is considered as a contour that does not need to be evaluated, i.e. does not need to be a target object; the preset specification is, for example, a threshold value of the contour area. In implementations where the determination of whether a contour meets specifications based on the area of the contour is made, the amount of computation for determining the geometry of the complex contour can be reduced by taking the area as a feature for making the determination. In some examples, the outline area may also be used to determine an open-loop outline, it being understood that under normal printing conditions, each solidification should be a closed outline, and when a recognition error or algorithm error occurs, the image may include an open-loop outline, for which an open-loop outline that does not form a closed image has an outline area of 0 or may be detected as non-conforming to specifications when the outline area is determined.

The aspect ratio of the contour can be used as a feature for evaluating the geometry of the contour, and in general, the contour of a slender structure in the printing can be determined as a part easily identified by mistake in the printing or a contour formed for a support structure when the aspect ratio of the contour is larger than a preset threshold, and in this case, the preset specification is, for example, the threshold of the aspect ratio of the contour, so that the aspect ratio of the contour can be used as a feature of the cured contour to identify the cured contour which can be used as a target object.

The contour perimeter area ratio can be used to evaluate the geometry of the contour, for example, when the contour perimeter area is relatively large, the contour can be determined to be in an elongated or linear configuration that is easily identified after printing as a false or formed contour for a support structure and is not generally the main structure of the target printing member, so that cured contours that are not of interest can be screened out therein by characterizing the contour perimeter area ratio as a cured contour.

In step S1028, the curing profile determined to be not in accordance with the preset specification is deleted, and the curing profile determined to be in accordance with the preset specification is retained to obtain the target object.

In step S1027, each curing profile is determined based on a preset criterion, and in step S1028, the curing profiles that do not meet the criterion are deleted based on the determination result, and the curing profiles that meet the preset criterion are retained, so that a target object that can be used for subsequently evaluating the printing quality of the current curing layer is determined. At least the outline which can be used for determining the main structure of the target printing component is reserved in the target object, the outline which is easy to generate errors is deleted, the calculation amount of the subsequent evaluation process (namely the matching process) can be reduced, and the accuracy of the result can be improved.

Here, steps S1026, S1027, and S1028 may be performed on a single curing profile, or performed sequentially, or may be performed on a plurality of curing profiles simultaneously, which is not limited in this application.

In some examples, the target object may also indirectly evaluate the effect of the support structure of the target printing member on the quality of the cured layer; for example, when only deformation of the support structure occurs in the target printing member, when the deformation does not affect the target printing member itself which is subsequently used as a product, no printing defect can be determined in the judgment of the printing quality of the current cured layer; when the printing defects of the supporting structure, such as distortion, affect the current curing layer, the occurrence of the printing defects of the current curing layer can be determined through analysis of the target object, so that the 3D printing control method provided by the application can avoid the influence on the printing process caused by single supporting structure errors.

It should be noted that the process of determining the target object in the current solidified layer image also includes a process of determining whether a solidified contour exists; the current solidified layer image is obtained by shooting, and the final image state is influenced by factors such as shooting precision, shooting time and the like besides the quality of the solidified layer. In some examples, when determining the curing profile from the current curing layer image, if the curing profile is not acquired therein, it may be determined that there is an error in the current curing layer, such as a failure in the photographing device, a failure in the photographing timing, a failure in the energy radiation system, etc., so that it may be determined that a corresponding print control job, such as error checking, parameter adjustment, etc., may be performed.

The target object is used for matching with the reference object, and the application also provides an implementation mode of how to determine the reference object from the slice image.

The slice image is a theoretical image of the target printing component expected to be obtained, in some examples, an open-loop contour (for example, a contour g in the embodiment shown in fig. 1) caused by an algorithm error or a narrow contour (for example, a contour h in the embodiment shown in fig. 1) which is not the main body of the target printing component exists in the slice image, and the narrow slice contour is easy to identify an error after being used for curing to form a curing contour, accordingly, one or more slice contours in the slice image can be judged to delete the slice contour which is not in accordance with the specification, namely, the matching process of the target object and the reference object can be simplified and a matching result can be obtained.

Referring to fig. 9, a schematic flow chart illustrating a method for controlling 3D printing according to an embodiment of the present application for determining a reference object is shown.

In certain embodiments, the manner in which the reference object is determined comprises the steps of:

in step S1031, it is determined whether the morphology of each slice contour in the slice image conforms to a preset specification.

The predetermined specification may be determined according to the requirement for the referenceable object, that is, the slice profile corresponding to the component region that can be used for evaluating the printing quality is determined in the slice image, for example, the narrow profile of the non-target printing component body or the open-loop profile erroneously formed by the algorithm as described above may be determined as a profile that does not conform to the predetermined specification, that is, is not required for evaluating the printing quality. The preset specification is used for obtaining (or defining) characteristics of the slice outline and detecting the slice outline according to the characteristics to form a judgment result, so that a specific characteristic selection mode can be customized based on the requirement of a reference object.

That is, in some embodiments, at least one of the contour size, the contour area, the contour geometry, the contour aspect ratio, and the contour perimeter-to-area ratio of the slice contour may be determined as a feature of the slice contour, and each slice contour may be determined according to the determined feature to determine a pruning operation for the slice contour.

The outline geometry is a geometric figure shape of the outline, such as a circle, a square, a star and the like; in some examples, the contour geometry also includes the morphology of the contour lines identified as open-loop contours, which are typically formed due to algorithm errors, etc., and in embodiments, slice contours identified as open-loop contours may be considered out of specification.

The contour dimension can be used for determining the geometric figure of the contour and the scale of the geometric figure, such as the values of parameters of length, width, radius and the like of the contour.

In some examples, the reduction operation on the contour may be determined based on the contour area, for example, when the area of the slice contour is smaller than a certain threshold, the solidified contour formed by the slice contour with an excessively small area is easy to identify an error after imaging, i.e. the slice contour is considered as a contour that does not need to be evaluated, i.e. does not need to be used as a reference object; the preset specification is, for example, a threshold value of the contour area. In implementations where the determination of whether a contour meets specifications based on the area of the contour is made, the amount of computation for determining the geometry of the complex contour can be reduced by taking the area as a feature for making the determination. In some examples, the outline area may also be used to determine an open-loop outline, it being understood that under normal printing conditions, each solidification should be a closed outline, and when a recognition error or algorithm error occurs, the image may include an open-loop outline, for which an open-loop outline that does not form a closed image has an outline area of 0 or may be detected as non-conforming to specifications when the outline area is determined.

The aspect ratio of the outline can be used as a characteristic for evaluating the geometrical shape of the outline, and in general, the outline which is presented as a slender structure in the printing process can be determined as a part which is easy to identify errors in the printing process when the aspect ratio of the outline is greater than a preset threshold value; the preset specification is, for example, a threshold value of the aspect ratio of the contour, so that the aspect ratio of the contour can be used as a feature of the slice contour to identify the slice contour that can be used as a reference object.

The contour perimeter area ratio can be used to evaluate the geometry of the contour, e.g., when the contour perimeter area is relatively large, the contour can be determined to be in an elongated or linear configuration, such configuration being prone to identify false contours after printing and generally not being the main structure of the target printing member, so that slice contours that do not need attention can be screened out therein by characterizing the contour perimeter area ratio as a slice contour.

In step S1032, the slice contour determined to not meet the preset specification is deleted, and the slice contour determined to meet the preset specification is retained to obtain a reference object.

In step S1031, one or more slice contours included in the slice image are determined based on a preset specification, and in step S1032, slice contours that do not meet the specification are deleted based on the determination result, and slice contours that meet the preset specification are retained, so that a reference object that can be used for subsequent evaluation of the printing quality of the current solidified layer is determined. At least the contour which can be used for determining the main structure of the target printing component is reserved in the reference object, the contour which easily causes the error of a judgment result (matching result) or cannot effectively evaluate the printing quality is deleted, the calculation amount of the subsequent evaluation process (namely, the matching process) can be reduced, and the accuracy of the result can be improved.

Here, steps S1031 and S1032 may be performed on a single slice contour, or performed sequentially, or performed on a plurality of slice contours simultaneously, which is not limited in this application.

Referring to fig. 1 and 10, fig. 10 is a schematic diagram illustrating a reference object determined from the image shown in fig. 1. As shown, fig. 1 shows a printed area and a slice image corresponding to a cured layer therein in an embodiment, where an outer rectangular frame line is, for example, the printed area, and the slice image includes a slice contour a, a slice contour b, a slice contour c, a slice contour d, a slice contour e, a slice contour f, a slice contour g, and a slice contour h in the printed area; the method includes the steps of judging whether each slice contour meets a preset specification or not based on an implementation mode of determining a reference object from slice images provided by the application, deleting the slice contour determined to be not in accordance with the preset specification, and reserving the slice contour determined to be in accordance with the preset specification, namely obtaining the reference object shown in fig. 10, wherein an outer rectangular frame line in a view of fig. 10 is a printing breadth range, inner slice contours a, b, c, d, e and f are reserved slice contours in accordance with the preset specification, and the reserved slice contours also form the reference object.

After the target object and the reference object are obtained in the above examples, the printing quality evaluation of the current solidified layer may be performed, please continue to refer to fig. 3, and in step S103, the matching result between the reference object and the target object is determined based on the preset matching rule. The reference object includes one or more slice profiles, the target object includes one or more curing profiles, and the matching result is based on a matching rule, and may be a result of outputting whether all curing profiles of the target object of the current curing layer are matched or a result of matching each curing profile, or a result of outputting whether all slice profiles of the reference object of the slice image are matched or a result of matching each slice profile.

The matching rule is used to determine whether the slice profile in the reference object corresponds to (coincides with) the curing profile in the target object, i.e. to evaluate whether the energy radiation system radiates energy from the slice image and forms a curing layer in the container with reference to the slice image.

Referring to fig. 11, a flowchart illustrating a method for controlling 3D printing according to an embodiment of the present disclosure for generating a matching result based on a reference object and a target object is shown.

In some embodiments, the method for determining the matching result between the reference object and the target object based on the preset comparison rule comprises the following steps:

in step S1041, determining a slice contour in the reference object as a reference contour;

in step S1042, a cured contour whose deviation from the reference contour is smaller than a preset threshold is searched for in the target object, and the searched cured contour is determined as a target contour matching the reference contour, or it is determined that the reference contour has a print defect when the cured contour is not searched.

The contour in the reference object is a slice contour remaining in the slice image, and by determining whether the slice contour in the reference object has a corresponding solidification contour, it can be determined whether the morphology of the current solidified layer is consistent with the theoretical slice contour or within an allowable error.

Here, it is determined whether the target object has a corresponding cured contour, that is, a cured contour whose deviation from the reference contour is smaller than a preset threshold is searched for in the target object in step S1042, where the preset threshold may be predefined, and when a cured contour meeting the deviation determined by the preset threshold is found, it is determined that the cured contour corresponds to the reference contour, that is, a target contour matching the reference contour is found; when the curing profile meeting the condition that the deviation from the reference profile is smaller than the preset threshold value cannot be found in the target object, the current curing layer is considered to have printing defects relative to the reference profile.

In other implementations, the curing profile in the target object may also be determined, and the reference object may be searched for the presence of a slice profile matching the curing profile. However, in the embodiment of finding whether a matching cured profile exists in the target object based on the reference profile, the problem of inaccurate cured profile, such as inaccurate quantity, caused by interference of the shooting precision of the current cured layer image, the shooting environment and the like can be avoided or reduced; when a contour matching the reference contour exists in the target object obtained from the solidified layer image, it can be assumed that a solidified layer solidified in accordance with the theoretical slice contour is obtained in printing.

In some embodiments, the method for finding a cured profile in the target object, which has a deviation from a reference profile smaller than a preset threshold value, comprises the following steps:

in one implementation, the reference contour is characterized as a reference coordinate point list, and a cured contour, in which a distance from each coordinate point in the reference coordinate point list to the cured contour is smaller than a preset threshold, is searched for in the target object.

In an ideal state, a cured contour that coincides with (overlaps with) the position of the reference contour should be present in the target object obtained from the cured layer image, and in the matching process, the target contour present in the target object with a deviation of the reference contour smaller than the allowable deviation threshold can be considered to match. The present application provides for the implementation of characterizing a reference contour as a list of reference coordinate points to determine whether it has a target contour in a target object by selecting a series of coordinate points on the reference contour to characterize the reference contour, which effectively reduces the computational effort of the matching process of the reference contour to the cured contour.

The specific rule for characterizing the reference contour as the list of reference coordinate points may be set according to the need for comparison, for example, the reference contour may be equally divided along the perimeter to extract the coordinate points on the equally divided points, or alternatively, the reference contour may be equally divided along a certain direction, such as the X direction or the Y direction in the image, to extract the coordinate points on the equally divided points; further alternatively, the coordinate points extracted from the reference contour may be determined according to the geometric state of the reference contour, and it should be understood that the reference coordinate point list is used to represent the shape of the reference contour, and for a straight line segment in the reference contour, fewer coordinate points may be selected accordingly, and for a curved line segment in the reference contour, more coordinate points may be selected thereon to be closer to the real shape of the reference contour.

Meanwhile, the number of the coordinate points represented by the reference contour can be determined according to the matching requirement, and generally, the larger the number of the coordinate points in the reference coordinate point list represented by the reference contour is, the more the reference coordinate point list can reflect the real form of the reference contour, but correspondingly, the calculation amount of the matching process is increased.

In this implementation, the reference contour is characterized as a list of reference coordinate points, and the cured contour included in the target object is a corresponding contour line, and the functional module for implementing the search for a target contour in the target object matching the list of reference coordinate points performs processes such as:

extracting a curing contour from the target object, calculating the distance from each coordinate point in the reference coordinate point list to the curing contour based on the reference coordinate point list of the reference contour, determining whether the distance from each coordinate point to the curing contour meets a set distance threshold, and when the distance from one or more coordinate points in the reference coordinate point list to the curing contour is found to be greater than the set distance threshold, determining that the curing contour cannot be matched with the reference contour; then another solidified contour is extracted from the target correspondence, the distance from each coordinate point in the reference coordinate point list to the solidified contour is calculated based on the reference coordinate point list of the reference contour, and when the distance from one or more coordinate points in the reference coordinate point list to the solidified contour is found to be greater than a set distance threshold value, the solidified contour and the reference contour are considered to be unmatched; repeating the above process until a target contour with a distance from each coordinate point in the reference coordinate point list to the cured contour being smaller than a preset threshold is found in the target object, wherein the distance from the coordinate point to the cured contour is, for example, the shortest distance from the point to the contour line.

In the searching process, for a reference contour, when a solidified contour can be searched and obtained in the target object and the distance from each coordinate point in the reference coordinate point list to the solidified contour is smaller than a preset threshold value, the reference contour is considered to have a matched target contour, namely, the solidification process based on the reference contour meets the printing quality requirement; in some examples, after the searchable curing profile is traversed in the target object, no target profile exists in the target object that satisfies that the distances to the reference profile are all less than a preset threshold, i.e., a print defect may be identified as being present in the curing process based on the reference profile.

In another implementation manner, each solidification profile in the target object is characterized as a target coordinate point list, and solidification profiles in which distances from each coordinate point in the target coordinate point list to the reference profile are smaller than a preset threshold value are searched for in the target object.

The present application provides embodiments for characterizing a cured contour of a target object as a list of target coordinate points, wherein for each cured contour, it can be considered as a linear contour formed by a set of different pixel locations in an image, and by selecting a series of coordinate points thereon to characterize the cured contour, the computational burden of the matching process between the cured contour and a reference contour can be effectively reduced. The specific rule for characterizing the curing profile as the target coordinate point list can be set according to the comparison requirement, for example, the curing profile can be equally divided along the perimeter to extract coordinate points on equally divided points, or alternatively, the curing profile can be equally divided along a certain direction, such as the X direction or the Y direction in the image, to extract coordinate points on equally divided points; further alternatively, the coordinate points extracted from the curing profile may be determined according to the geometric state of the curing profile, and it should be understood that the target coordinate point list is used to represent the shape of the curing profile, and that fewer coordinate points may be selected for straight line segments of the curing profile, and more coordinate points may be selected for curved line segments of the curing profile to be closer to the real shape of the curing profile.

Meanwhile, the number of coordinate points represented by the curing profile can be determined according to the matching requirement, generally, the more the number of coordinate points in a target coordinate point list represented by the curing profile is, the more the target coordinate point list can reflect the real form of the curing profile, but correspondingly, the calculated amount in the matching process is increased.

In this implementation, the reference contour is a contour line of a slice contour, and the cured contour included in the target object is characterized by a list of target coordinate points, and the functional module for implementing the search for the list of target coordinate points matching the reference contour in the target object performs a process such as:

extracting a target coordinate point list corresponding to a curing contour from the target object, calculating the distance from each coordinate point in the target coordinate point list to the reference contour, and determining whether the distance from each coordinate point to the reference contour meets a set distance threshold, wherein when the distance from one or more coordinate points in the target coordinate point list to the reference contour is found to be greater than the set distance threshold, the curing contour corresponding to the target coordinate point list is considered not to be matched with the reference contour; then extracting a target coordinate point list corresponding to another curing contour from the target correspondence, determining whether the distance from each coordinate point in the currently extracted target coordinate point list to the reference contour is smaller than a set distance threshold, and when the distance from one or more coordinate points in the target coordinate point list to the reference contour is found to be larger than the set distance threshold, determining that the curing contour corresponding to the target coordinate point list cannot be matched with the reference contour; repeating the above process, so as to find a cured contour in the target object, wherein the distance from each coordinate point in the target coordinate point list to the reference contour is smaller than a preset threshold value, and the cured contour is a target contour matched with the reference contour. The distance from the coordinate point to the reference contour is, for example, the shortest distance from the point to the contour line.

In the searching process, for a reference contour, when a target coordinate point list can be searched in a target object and the distance from each coordinate point to the reference contour is less than a preset threshold value, the reference contour is considered to have a matched target contour, namely, the curing process based on the reference contour meets the printing quality requirement; in some examples, after traversing the searchable list of target coordinate points in the target object, the absence of a list of target coordinate points in the target object that satisfy each coordinate point having a distance to the reference contour that is less than a preset threshold may be identified as having a print defect based on the curing process of the reference contour.

In the above examples provided by the present application, either the reference contour or the cured contour is characterized as a coordinate point list, and the other is represented by a contour line, and by calculating the distance (e.g., the minimum distance) from the coordinate point to the contour line, the matching accuracy can be ensured in a process of effectively reducing the amount of matching calculation.

In some embodiments, the determining the matching result between the reference object and the target object based on the preset comparison rule further includes: and deleting the searched target contour from the target object so as to search a curing contour of which the deviation from the next reference contour is smaller than a preset threshold value in the updated target object.

That is, when a slice contour is determined as a reference contour to search for a matching target contour in a target object, after the target contour is found, that is, the curing process performed based on the slice contour is considered to satisfy the printing requirement, the target contour matching the slice contour is deleted from the target object, thereby obtaining an updated target object; and selecting another slice contour in the reference object as a reference contour, and searching the corresponding target contour in the updated target object. Therefore, on one hand, the calculation amount required by the matching process can be reduced, repeated searching is avoided, and on the other hand, by deleting the matched target contour, the mutual interference of different curing contours can be avoided or reduced, and the accuracy of the matching result is improved.

It should be understood that when the slice image corresponding to the current solidified layer image has a plurality of slice outlines, a matching process for completing finding a target outline in the target object is performed on each of the plurality of slice outlines, and then the printing evaluation on the current solidified layer is completed, so that a matching result of the target object and the reference object can be obtained. When each slice contour in the reference object has a matched curing contour in the target object, it indicates that the current curing layer of the target printing component corresponding to the target object has formed a curing layer meeting the printing requirement according to the theoretical contour of the slice image, and the printing of the current curing layer is qualified or has no printing defect.

It should be understood that the matching of the target object and the reference object corresponding to the current solidified layer image and the slice image in the present application may be set as image capturing and subsequent matching for each solidified layer according to the detection requirement, or alternatively, the printing monitoring and matching in the foregoing embodiment may be performed once per several printed layers. After the current solidified layer is qualified for printing, continuing to print the next solidified layer or continuing to print a plurality of solidified layers based on the set monitoring frequency, repeating the matching process based on the current solidified layer image and the slice image corresponding to the current solidified layer image to obtain the matching result again.

In some embodiments, the method for controlling 3D printing further includes a step of recording the matching result and at least one of a slice image, a current solidified layer image, a reference object, and a target object corresponding to the matching result.

After the reference object and the target object corresponding to the current solidified layer image and the slice image are matched to obtain a matching result, at least one of the matching result and the slice image, the current solidified layer image, the reference object, and the target object corresponding to the matching result may also be recorded, the specific recording mode is, for example, to generate a detection log, by recording the matching result and the object pointed by the matching result, i.e., the specific slice image (or the current solidified layer image) in which the print defect occurred, thus helping to determine the factors of print defect formation, for example, an unreasonable design of the geometry of the printing member, or printing errors for the energy control in the energy radiation system, or calculation errors for the acquisition process of the reference or target object, etc., the skilled person can better analyze and control the subsequent printing operation on the basis of the records. The detection log is recorded in a storage medium of the printing apparatus, or recorded in another electronic apparatus or a memory associated with the printing apparatus, for example, which is not limited in this application.

When each slice contour in the reference object can find a matched curing contour in the target object, the current curing layer can be considered, and the printing of the curing layer can be continued.

In step S104, the 3D print job is controlled based on the matching result.

In some embodiments, the manner of controlling the 3D print job based on the matching result includes any one of:

when each slice contour in the reference object has a matched curing contour in the target object, continuing to print the next curing layer; when each slice contour in the reference object can find a matched curing contour in the target object, the current curing layer can be considered to form a curing layer meeting the printing requirement according to the theoretical contour of the slice image, and the printing of the current curing layer is qualified or has no printing defect, so that the printing of the next curing layer can be continued.

Alternatively or additionally, a printing intervention instruction is generated when the presence of one or more slice contours in the reference object is deemed to be a printing defect.

In some scenarios, when at least one slice contour is present in the reference object and a matching cured contour cannot be found in the target object, the slice contour that cannot be matched can be identified as having a print defect.

Through the above steps 101 to 103, all of the plurality of target printing members currently printed may be inspected to determine whether there is a print defect in any of the target printing members.

Continuing back to step S100 in fig. 2, upon detecting that at least one of the plurality of target printing members currently printed has a print defect, reference slice images of the plurality of target printing members are acquired.

And performing image processing on the reference slice image of the target printing components corresponding to the at least one target printing component to obtain the contour of the at least one target printing component.

In some embodiments, the means for acquiring reference slice images of the plurality of target printing members comprises at least one of:

in some cases, if the target printed material has a configuration with the largest bottom or the largest top, wherein the bottom refers to a portion connected to the component platform and the top refers to a portion opposite to the bottom, but not limited thereto, the portion connected to the component platform may be the top and the portion opposite to the top may be the bottom. For such a target printing means, the first layer slice image or the last layer slice image corresponding to the target printing means may be used as a reference slice image for the target printing means. For example, for some dental models without support, the size of the first layer slice image is the largest, i.e. the first layer slice image can be directly used as the reference slice image of the dental model; or, for some dental models, although the supporting form is simpler and does not interfere with the dental model, the first layer slice image can still be directly used as the reference slice image of the dental model.

In some cases, if the target printing member is a structure of a straight cylinder type or a reduced type, the size of the current layer slice image of the target printing member is the largest, and for such target printing member, the current layer slice image corresponding to the target printing member may be used as the reference slice image of the target printing member. For example, for some dental models, the shape of which is relatively simple, where the shape is worth simply that the number of contours does not become too large or becomes too large, but still easily recognized as the same part, for which the dental model image has only one outer contour at the beginning, but printed to the extent that a plurality of small contours may appear later, the current layer slice image may be used as the reference slice image for the dental model.

In some cases, when the target printing component is, for example, an industrial part with a complex shape, it further includes a support structure during printing, that is, includes a target printing component entity and a support body, so that for such target printing component, a projection image obtained by projecting both the target printing component entity and the support body related thereto can be used as a reference slice image of the target printing component.

A reference slice image of the corresponding target printing member may be acquired in any of the above-described manners.

Referring to fig. 12, a schematic diagram of a reference slice image of a currently printed target printing component in an embodiment of the control method for 3D printing according to the present application is shown. In this illustration, the size of the reference slice image corresponds to the size of the radiation area of the energy radiation device in the energy radiation system. The reference slice image may be, for example, a binary image, in which the background is pure black (the gray scale value is 0) and the target printing member is pure white (the gray scale value is 255), but not limited thereto, and the background and the target printing member may take other different forms as long as the background and the target printing member can be clearly distinguished, that is, the target printing member can be clearly detected from the illustration. In fig. 12, the target printing member may be, for example, a dental cast. Note that the reference slice images are of a plurality of target printing members currently printed, and still by way of example, fig. 12 shows reference slice images of three target printing members currently printed. Of course, there are other variations, such as if a first target printing member and a second target printing member are currently printed, then a reference slice image including the first target printing member and a reference slice image of the second target printing member are displayed.

In addition, as described above, for some target printing members having a complicated shape, the entity of the target printing member and its associated support are projected together to obtain a projection image, and the projection image is used as a reference slice image of the target printing member. Fig. 13 is a schematic diagram of a first slice image of a target printing element in an embodiment, and in fig. 13, there is no solid target printing element but only supports in the first slice image, and each support is relatively scattered and irregular in shape. For the target printing component of this type, a projection image is obtained by projecting the entity of the target printing component and its related support together, and the projection image is used as a reference slice image of the target printing component, as shown in fig. 14, and is displayed as a schematic diagram of the projection image formed by projecting the target printing component in fig. 13.

Step S110, performing image processing on the reference slice image corresponding to at least one target printing component in the reference slice images of the plurality of target printing components to obtain an outline of the at least one target printing component.

Please refer to fig. 15, which is a flowchart illustrating step S110 in fig. 2 according to an embodiment.

As shown in fig. 15, the image processing on the reference slice image of the plurality of target printing components corresponding to the at least one target printing component to obtain the contour of the at least one target printing component includes the following steps:

in step S1101, a marker point located within a reference slice image of at least one target printing member is acquired.

In some embodiments, marking points may be captured on at least one target printing component for which a print defect is detected. The acquisition mode of the mark point may include but is not limited to: and setting one or more marking points in the reference slice image of the detected at least one target printing component with the printing defects by a manual mode or a detection program. Taking a manual manner as an example, when a certain target printing component with a printing defect is detected, one or more marking points are manually selected for the target printing component in a reference slice image, wherein the marking points are located in the reference slice image of the target printing component. Taking a detection program as an example, when a certain target printing component with a printing defect is detected, one point or a plurality of mark points in a reference slice image of the target printing component are automatically acquired by the detection program.

In the embodiment as shown in fig. 12, assuming that a second target printing member (the three target printing members in fig. 12 may be referred to as a first target printing member, a second target printing member, and a third target printing member from left to right, respectively) of the three target printing members currently printed is detected to have a print defect in step S100, one or more mark points may be acquired in the reference slice image of the second target printing member manually or by a detection program.

In step S1102, image processing is performed on the reference slice image of the at least one target printing component according to the mark points, so as to obtain an outline of the at least one target printing component.

In some embodiments, for the above step S1102, the obtaining the outline of the at least one target printing component may include: and performing connected domain calculation on the reference slice image of the corresponding at least one target printing component according to the mark points to obtain the outline of the at least one target printing component.

Still taking fig. 12 as an example, in fig. 12, when a print defect is detected in the second target printing component, one or more mark points may be obtained in the reference slice image of the second target printing component manually or by a detection program, and a connected domain calculation is performed on the second target printing component according to the obtained one or more mark points, so as to obtain an outermost layer contour representing the second target printing component. In some embodiments, the contour may include a contour line, the extent of which is defined by the contour line, as shown in fig. 17 a. Alternatively, in some embodiments, the profile is filled within its defined range, as shown in FIG. 17 b. Still alternatively, in some embodiments, the contour includes a contour line and is filled within a range defined by the contour line, as shown in fig. 17 c.

For some target printing components with complex structures, if the first layer slice image of the target printing component shown in fig. 13 is taken as a reference slice image, which includes many small outlines, the small outlines are likely to be separated from each other, so it is difficult to obtain the outermost layer outline corresponding to the target printing component by performing connected domain calculation through one or a few mark points, unless valid mark points are provided in all existing small outlines. With the projection image of the target printing member and its support shown in fig. 14 as a reference slice image, the outermost layer contour corresponding to the target printing member can be obtained by performing connected domain calculation through one or a few of the marking points.

Returning to fig. 2, step S120, generating a mask image according to the contour of at least one target printing member; wherein a region of the mask image corresponding to the outline of the at least one target printing member is an exposure-inhibited region.

In step S120, the step of generating a mask image according to the contour of the at least one target printing member further includes: and transferring the outline of the at least one target printing component to a corresponding area in an existing mask image to obtain the mask image.

The existing mask image is the previously stored mask image. In some embodiments, the existing mask image is an initial mask image if a target printing member having a print defect has not been detected before. In some embodiments, if at least one target printing component having a print defect has been previously detected and a mask image corresponding to the at least one target printing component having a print defect is generated therefrom, the existing mask image is the most recent (latest) mask image. In practice, in some implementations, only one mask image is stored as an existing mask image, and when a new mask image is generated, the latest mask image is overwritten by the previous mask image and the latest mask image is used as the existing mask image. In some implementations, the mask images may be stored in chronological order, and at the time of invocation, the temporally closest one is recalled as the existing mask image.

With respect to the initial mask image, in some embodiments, an initial mask image may be initially pre-produced or stored. Please refer to fig. 16, which is a schematic diagram illustrating an initial mask image produced by the control method for 3D printing according to an embodiment of the present application. As shown in fig. 16, the initial mask image may be, for example, a pure white (gray value of 255) mask image having a size corresponding to the size of the radiation breadth of the energy radiation device in the energy radiation system.

Still taking fig. 12 as an example, in fig. 12, the second target printing component is detected to have a printing defect, and a connected component calculation is performed on one or more mark points acquired in a reference slice image of the second target printing component to obtain an outline representing the second target printing component, and the outline of the second target printing component may be in the form of fig. 17a, 17b, 17c or the like. In this step S120, the contour of the second target printing member (fig. 17a, 17b, or 17c) obtained from the reference slice image of fig. 12 is transferred to the corresponding region in the existing mask image (e.g., the initial mask image shown in fig. 16), so as to generate the mask image shown in fig. 18, wherein the region in the mask image corresponding to the contour of the second target printing member can be set to be pure black (the gray value is 0).

In step S130, a mask operation is performed on the slice images of the plurality of target printing members using the mask image to execute a print job.

It is assumed that when the slice images of the plurality of target printing members shown in fig. 19 are obtained and printed, the slice images of the three target printing members in fig. 19 can be subjected to a masking operation using the mask image shown in fig. 18 to obtain an actual projection image as shown in fig. 20. As shown in fig. 20, since the area of the mask image corresponding to the second target printing member shown in fig. 18 is a pure black color, the radiation energy of the energy radiation device in the energy radiation system cannot penetrate the mask image and is projected onto the member table, and therefore, the second target printing member will not continue to print, and the first target printing means and the third target printing means will continue to form the cured layer corresponding to the sliced image in fig. 19, so that the entire printing process is not interrupted, the printing efficiency is improved, and it is possible to prevent the second target printing member having a print defect from interfering with or contaminating the first and third target printing members, the photocurable material, the film, or the corresponding mechanism during printing, and, of course, since the printing process of the second target printing means is terminated, material loss due to printing of the second target printing means can be saved.

Subsequently, by using the control method for 3D printing of the present application, the currently printed first target printing component and third target printing component can be continuously detected to determine whether there is a printing defect in them, whether to generate a new mask image is determined according to the detection result, and the first target printing component and third target printing component are subjected to a masking operation according to the new mask image.

For example, still taking the above example as an example, in a subsequent printing process, when it is detected that the first target printing member of the currently printed first target printing member and third target printing member has a print defect, the reference slice images of the currently printed first target printing member and third target printing member are obtained, as in the form shown in fig. 21; next, the reference slice image of the first target printing member may be subjected to image processing to obtain a contour of the first target printing member, and the contour of the first target printing member may be transferred to a corresponding region in the existing mask image (as shown in fig. 18), so as to generate a mask image as shown in fig. 22, where the region in the mask image corresponding to the contour of the first target printing member and the region corresponding to the contour of the second target printing member may be set to pure black (with a grayscale value of 0).

It is assumed that when the slice images of the plurality of target printing members as shown in fig. 23 are obtained and printed, the mask images shown in fig. 22 are used to perform a masking operation on the slice images of the first target printing member, the second target printing member, and the third target printing member in fig. 23 to execute a print job to obtain an actual projection image as shown in fig. 24. As shown in fig. 24, since the areas of the mask image corresponding to the first target printing member and the second target printing member are in pure black, the radiation energy of the energy radiation device in the energy radiation system cannot penetrate the mask image and be projected onto the member stage, and therefore, the first target printing member will not continue to print (the second target printing member will not continue to print in the previous mask operation), and the third target printing member will continue to form the solidified layer corresponding to the slice image in fig. 24.

In this regard, in the 3D printing control method provided by the first aspect of the present application, when a printing condition of a plurality of target printing members is detected during a printing process, and a printing defect of at least one target printing member is detected during the printing process, a reference slice image of the at least one target printing member is subjected to image processing to obtain a contour corresponding to the at least one target printing member, a mask image is generated according to the contour of the at least one target printing member, wherein a region in the mask image corresponding to the contour of the at least one target printing member is an exposure-inhibited region, the mask image is used to perform a masking operation on the slice images of the plurality of target printing members to perform a printing job, so that the printing of the at least one target printing member having the printing defect is suspended and the printing of other normal target printing members can be continued, the printing process is not interrupted, at least one target printing component with printing defects can be prevented from interfering or polluting other target printing components, light curing materials, films or corresponding mechanisms in the printing process, and time cost and material cost can be saved.

The application also provides a method for acquiring the reference slice images of the plurality of target printing components, and ensuring that the size of the obtained reference slice images is maximum or large enough to avoid influencing subsequent printing, so that the target printing components with printing defects can be completely shielded in the generated mask image.

The present application further provides a control system for 3D printing in a second aspect, please refer to fig. 25, which shows a simplified block diagram of the control system for 3D printing in the second aspect of the present application in an embodiment.

As shown, the control system 3 for 3D printing includes an acquisition module 30 and a processing module 31.

The acquiring module 30 is configured to acquire reference slice images of a plurality of target printing components according to any one of the embodiments provided in the first aspect of the present application when detecting that at least one of the plurality of target printing components currently printed has a print defect.

The processing module 31 is configured to perform image processing on a reference slice image of the plurality of target printing components, where the reference slice image corresponds to the at least one target printing component, so as to obtain an outline of the at least one target printing component; and generating a mask image according to the outline of the at least one target printing member to enable the 3D printing device to perform a printing job by masking the slice images of the plurality of target printing members based on the mask image, wherein an area corresponding to the outline of the at least one target printing member in the mask image is an exposure-inhibited area.

Here, a specific manner of performing, by the processing module 31, image processing on a reference slice image corresponding to the at least one target printing component among reference slice images of the plurality of target printing components to obtain a contour of the at least one target printing component may refer to an embodiment provided in the first aspect of the present application, and an implementation manner of generating a mask image according to the contour of the at least one target printing component by the processing module 31 to enable the 3D printing apparatus to mask the slice images of the plurality of target printing components based on the mask image to perform a print job may refer to the embodiment provided in the first aspect of the present application.

Fig. 26 shows a simplified block diagram of a control system for 3D printing provided for the second aspect of the present application in another embodiment. As shown in fig. 26, the control system 3 for 3D printing provided by the present application may further include a detection module 32, configured to detect a plurality of target printing members currently printed to determine whether any of the target printing members has a printing defect. The specific manner of detecting the plurality of target printing components currently printed by the detection module 32 to determine whether any target printing component has a printing defect may refer to the embodiment provided in the first aspect of the present application.

In some embodiments, each functional module in the control system for 3D printing may be a software module, which may also be configured in a software system based on a programming language. The software modules may be provided by a system of electronic devices, such as those loaded with APP applications or having web page/website access capabilities, including in some embodiments memory, memory controllers, one or more processing units (CPUs), peripheral interfaces, RF circuitry, audio circuitry, speakers, microphones, input/output (I/O) subsystems, display screens, other output or control devices, and external ports, which communicate via one or more communication buses or signal lines. The electronic device includes, but is not limited to, personal computers such as desktop computers, notebook computers, tablet computers, smart phones, smart televisions, and the like. The electronic device can also be an electronic device consisting of a host with a plurality of virtual machines and a human-computer interaction device (such as a touch display screen, a keyboard and a mouse) corresponding to each virtual machine.

In some embodiments, the control system for 3D printing obtains reference slice images of a plurality of target printing components currently printed, performs image processing on the reference slice images to obtain a profile of at least one target printing component with a print defect, and each functional module that generates a mask image according to the profile of at least one target printing component and the reference slice profiles of the plurality of target printing components may be cooperatively implemented by various types of devices (such as a terminal device, a server cluster, or a cloud server system), or a computing resource such as a processor, a communication resource (such as for supporting communication in various manners such as optical cable and cellular).

The cloud server system may be arranged on one or more entity servers depending on various factors such as function, load, and the like. When distributed in a plurality of entity servers, the server side can be composed of servers based on a cloud architecture. For example, a Cloud-based server includes a Public Cloud (Public Cloud) server and a Private Cloud (Private Cloud) server, wherein the Public or Private Cloud server includes Software-as-a-Service (SaaS), Platform-as-a-Service (PaaS), Infrastructure as a Service (IaaS), and Infrastructure as a Service (IaaS). The private cloud service end is used for example for an Ariid cloud computing service platform, an Amazon (Amazon) cloud computing service platform, a Baidu cloud computing platform, a Tencent cloud computing platform and the like. The server may also be formed by a distributed or centralized cluster of servers. For example, the server cluster is composed of at least one entity server. Each entity server is provided with a plurality of virtual servers, each virtual server runs at least one functional module in the generation system, and all the virtual servers are communicated through a network.

The network may be the internet, a mobile network, a Local Area Network (LAN), a wide area network (WLAN), a Storage Area Network (SAN), one or more intranets, etc., or a suitable combination thereof, and the types of the client, the server, or the types or protocols of the communication networks between the publisher terminal and the server, and between the responder terminal and the server, etc. are not limited in this application.

In some embodiments, the 3D printing control system 3 provided in the second aspect of the present Application is, for example, a plug-in, an SDK (Software Development Kit), an API (Application Programming Interface), a framework, or the like in an actual scenario, and provides the plug-in, the SDK, the API, or the framework to a server or an electronic device, so that the server or the electronic device, such as the control Software of the printing device, can implement the functions of the obtaining module 30, the processing module 31, and the detecting module 32, that is, the 3D printing control method described in the first aspect of the present Application can be implemented. In the present form, the control system may, for example, expand functional modules in control software of the printing apparatus.

In some embodiments, each functional module in the control system 3 for 3D printing provided in the second aspect of the present application may be embedded in an electronic device APP, and the APP of the electronic device may obtain the current cured layer image and the slice image from an electronic device storage medium or other devices, servers, etc. in network communication with the electronic device, such as a camera. In determining the target object and the reference object based on the current solidified layer image and the slice image, and in comparing the target object and the reference object under a preset matching rule, in some examples; the functions of the control system 3 may be implemented by computing resources provided by electronic devices used for configuring the control system, and in other examples, the computing resources required for performing the computation may be allocated to terminal devices, servers, cloud server systems, processors, or the like in network communication with the devices; meanwhile, the target object, the reference object and the matching result generated by the control system 3 in the calculation process can be stored locally in the device, can be transmitted to a terminal device, a server, a cloud server system, a processor or the like of the device for network communication, and can be provided to other application programs or modules for use.

In some embodiments, the control system 3 for 3D printing provided in the second aspect of the present application is a software module running on a server side, which may also be a distributed and parallel computing platform composed of a plurality of servers, and in a usage scenario, the required current solidified layer image and slice image may be uploaded to the platform to perform a computing process on the target object and the reference object and a matching process on the target object and the reference object. The server side can execute a calculation process based on the storage data in the storage medium of the server side or data from other equipment in communication with the server side, so that the target object, the reference object and the matching result obtained through calculation can be stored by the server side and can also be provided to other application programs or modules for use in controlling the printing operation.

The present application also provides, in a third aspect, a control system for a 3D printing apparatus, the 3D printing apparatus including: a shaping chamber, an energy radiation system, and a component platform that accumulates a cured layer that is selectively cured by the energy radiation system, the control system comprising: the shooting device is used for shooting images in the forming chamber to obtain current solidified layer images of a plurality of currently printed target printing components; and the processing device is connected with the shooting device and used for detecting whether a target printing component with a printing defect exists or not according to a current cured layer image and a corresponding slice image of a plurality of currently printed target printing components, acquiring a reference slice image of the plurality of target printing components when the condition that at least one target printing component in the plurality of currently printed target printing components has the printing defect is detected, performing image processing on the reference slice image corresponding to the at least one target printing component in the reference slice images of the plurality of target printing components to obtain the contour of the at least one target printing component, and generating a mask image according to the contour of the at least one target printing component, wherein the area corresponding to the contour of the at least one target printing component in the mask image is an exposure-inhibited area.

Typically, the range of movement of the component platform in the 3D printing apparatus is also limited to the forming chamber, which contains the container for holding the printing material, and the currently cured layer is formed by receiving the radiation energy at the printing reference surface of the container.

The photographing devices include, but are not limited to: a camera, a video camera, an image pickup module in which a lens and a CCD are integrated, an image pickup module in which a lens and a CMOS are integrated, or the like. In this embodiment, the capturing device captures an image inside the molding chamber to obtain an image of a current solidified layer of the actual printing member.

The processing procedure performed by the processing device may refer to the embodiments provided in the first aspect of the present application.

In one example, the processing device is connected to the camera through a data line or is connected to the camera through communication, and is an electronic device capable of performing digital calculation and logic operations, including but not limited to: embedded electronic devices, computer devices containing one or more processors, single-chip computers containing processors, and the like. The processing means may also share an electronic device with the control means of the printing apparatus described above or be configured separately, the processing means and the control means being in data communication via a data line or a program interface, whereby the matching result is transmitted to the control means of the printing apparatus.

Taking fig. 4 as an example, the control device 15 sends a control command to the Z-axis drive mechanism 13 and the processing device 22 at the same time. For another example, still taking fig. 4 as an example, the control device 15 sends the same control command to the shooting device 21 and the processing device 22 at the same time; the control device 15 may also send some control instructions to the processing device 22 separately, and the processing device 22 controls the shooting device 21 to take a picture based on the control instructions.

The processing device can be further provided with a plurality of functional units to realize different functions, such as a functional unit for detecting a plurality of currently printed target printing members to determine whether a printing defect exists in any of the target printing members, a functional unit for acquiring reference slice images of the plurality of target printing members when a printing defect exists in at least one of the plurality of currently printed target printing members is detected, a functional unit for performing image processing on the reference slice image corresponding to the at least one target printing member in the reference slice images of the plurality of target printing members to obtain an outline of the at least one target printing member, and a functional unit for generating a mask image according to the outline of the at least one target printing member. The functional units may be software modules, which may also be configured in a software system based on a programming language. The software modules may be provided by a system of electronic devices, such as those loaded with APP applications or having web page/website access capabilities, including in some embodiments memory, memory controllers, one or more processing units (CPUs), peripheral interfaces, RF circuitry, audio circuitry, speakers, microphones, input/output (I/O) subsystems, display screens, other output or control devices, and external ports, which communicate via one or more communication buses or signal lines. The electronic device includes, but is not limited to, personal computers such as desktop computers, notebook computers, tablet computers, smart phones, smart televisions, and the like. The electronic device can also be an electronic device composed of a host with a plurality of virtual machines and a human-computer interaction device (such as a touch display screen, a keyboard and a mouse) corresponding to each virtual machine.

In an implementation scenario, the camera and the processing device may be integrated into a device with processing function, which may be a general-purpose or special-purpose computing system such as: personal computers, server computers, hand-held or portable devices, tablet devices, multiprocessor systems, microprocessor-based systems, set top boxes, programmable consumer electronics, network PCs, minicomputers, mainframe computers, and the like. In other implementations, the processing device is, for example, a device communicatively coupled to the camera or configured in a device communicatively coupled to the camera.

In certain embodiments, the control system provided in the fourth aspect of the present application further comprises: and the light environment providing device is used for providing a stable light environment during the period that the shooting device shoots the images in the forming chamber.

The shooting device is used for shooting images in the forming chamber to obtain the current solidified layer image of the actual printing component, so that the obtained current solidified layer image can reduce the interference of the external environment, for example, the accuracy of the current solidified layer image obtained by the shooting device can be influenced by the conditions of the intensity change of the external environment light, the shadow shielding and the like during shooting. To this end, the control system further comprises: a light environment providing device arranged around the energy radiation system for providing a stable light environment during shooting by the shooting device; in some examples, the light environment providing device provides uniform illumination intensity of the printing reference surface, namely, the formation of light and shade in the current solidified layer image caused by local reflection and the like can be avoided. The light environment providing device can be externally arranged on the 3D printing equipment. For example, the light environment providing device may provide a light environment for the photographing device using an external light source (e.g., an LED lamp).

In some embodiments, the light environment providing device includes an isolation barrier and a light source. Wherein the isolation barrier is used for isolating at least the irradiation range of the energy radiation system from the external environment. The light source is arranged in the isolation barrier and used for providing a stable light environment for the shooting device.

Here, the isolation barrier mainly serves to shield light or reflect light. For example, the light shielding barrier is a light shielding plate, a light reflecting plate, a light shielding cloth, a light reflecting cloth, a light shielding cover, or the like. The light source may provide a light environment at all times during operation of the 3D printing device. Or according to the principle of a flash lamp, the light source provides a light environment when the shooting device shoots so as to ensure the stable exposure of the shooting device. The light source may be an LED light source, or a flash, etc.

The present application also provides in a fourth aspect a 3D printing apparatus comprising: a container for holding a photocurable material to be cured; an energy radiation system for selectively curing the light-curable material according to the data of the received slice image to form a cured layer; a component platform in the container for cumulatively attaching the solidified layer; the Z-axis driving mechanism is connected with the component platform and is used for adjusting the distance from the component platform to the printing reference surface; the control system according to any one of the embodiments of the fourth aspect of the present application, configured to detect a plurality of target printing members currently being printed, and generate a mask image corresponding to at least one target printing member when it is detected that at least one target printing member has a print defect, where an area in the mask image corresponding to an outline of at least one target printing member is an exposure-inhibited area; and the control device is connected with the Z-axis driving mechanism and the energy radiation system and is used for controlling the Z-axis driving mechanism and the energy radiation system according to the mask image.

Please refer to fig. 4, which is a schematic structural diagram of the 3D printing apparatus in an embodiment.

As shown, the 3D printing apparatus includes: a container 11, an energy radiation system 14, a component platform 12, a Z-axis drive mechanism 13, and a control device 15. The container 11 contains the light-curable material to be cured, and in some applications, is also referred to as a resin tank. Such materials include, but are not limited to: such as a photosensitive resin, or a photosensitive resin mixed with other materials to improve physical and chemical characteristics of the three-dimensional object being manufactured. The container has a transparent bottom surface for transmitting radiant energy such as light energy, electromagnetic energy, and the like. Of course, in other possible embodiments, the 3D printing device may also be a top-surface exposure based device, such that the energy radiation system projects radiant energy, such as light energy, electromagnetic energy, etc., onto a printing reference surface within the container.

In the embodiment shown in fig. 4, the energy radiation system 14 is located on the bottom surface of the container and radiates energy facing the transparent floor, which includes but is not limited to: a surface exposure type energy radiation device, a scanning radiation type energy radiation device, or the like. The material of the bottom surface of the energy container irradiated with the radiation will be selectively cured, and the cured layer thereof is attached to the component platform. In order to build up layer by layer to obtain a three-dimensional object, the Z-axis driving mechanism 13 drives the component platform 12 to strip the solidified layer from the bottom surface of the container and provide a layer height interval of the new solidified layer so as to build and attach each layer of solidified layer on the component platform. The control device 15 is respectively connected with the energy radiation system 14 and the Z-axis driving mechanism 13, and controls the two to work cooperatively so as to realize the layer-by-layer manufacturing of the three-dimensional object. The control device 15 is typically an electronic device including a processor, which includes but is not limited to: computer equipment, industrial personal computers, electronic equipment based on embedded operating systems and the like.

The control system includes a camera, and as shown in the figure, the camera is arranged at the bottom of the container in the bottom exposure device to acquire an image of the printing reference surface. The processing device in the control system is, for example, a software module configured in the control device, or an electronic device communicatively connected to the control device, the processing device is connected to the shooting device, and is configured to detect whether there is a target printing member with a print defect according to a current cured layer image and a corresponding slice image of a plurality of target printing members currently printed, acquire a reference slice image of the plurality of target printing members when it is detected that there is a print defect in at least one of the plurality of target printing members currently printed, perform image processing on the reference slice image corresponding to the at least one target printing member in the reference slice images of the plurality of target printing members to obtain an outline of the at least one target printing member, and generate a mask image according to the outline of the at least one target printing member, wherein a region of the mask image corresponding to a contour of the at least one target printing member is an exposure-inhibited region. The processing device may transmit the processing result to the control device so that the control device can control the energy radiation system 14 and the Z-axis drive mechanism 13 according to the mask image to achieve control of the printing process.

Please refer to fig. 27, which is a schematic structural diagram of a top-exposed 3D printing apparatus according to an embodiment of the present application. The 3D printing apparatus comprises a container 41, an energy radiation system 44, a Z-axis drive mechanism 43 and a doctor blade device 46, and a control system as described in the fourth aspect of the present application. Unlike bottom-exposed 3D printing devices, the energy radiation system 44 is located above the container opening and radiates energy towards the material surface (i.e., the printing reference surface) within the container, which includes but is not limited to: a surface exposure type energy radiation device, a scanning radiation type energy radiation device, or the like. The material of the bottom surface of the energy container irradiated with the radiation will be selectively cured, and the cured layer thereof is attached to the component platform. For layer-by-layer accumulation to obtain a three-dimensional object, the Z-axis driving mechanism 43 drives the member platform 42 to move downward by a layer height distance, so that the material contained in the container 41 is covered on the solidified layer. The scraper means 46 is moved from one side of the container to the other to smooth the surface of the material in the container 41. The control device 45 is respectively connected with the energy radiation system 44, the Z-axis driving mechanism 43 and the scraper device 46, and controls the three to work cooperatively to realize the layer-by-layer manufacturing of the three-dimensional object. The control device 45 is typically an electronic device including a processor, which includes but is not limited to: computer equipment, industrial personal computers, electronic equipment based on embedded operating systems and the like.

Taking a top-surface exposure-based 3D printing apparatus as an example, the top-surface exposure-based 3D printing apparatus is prone to cause a defect problem of a manufactured three-dimensional object when performing operations such as energy radiation and smoothing, and therefore, some 3D printing apparatuses are provided with a sensing device for detecting an abnormality of the 3D printing apparatus during these operations. However, not only does the 3D printing apparatus need to be modified to provide sensing devices, but a sensing device can generally only provide one type of detection for the 3D printing apparatus. For example, an energy abnormality or the like output from the energy radiation system is detected by a light intensity sensor mounted on the energy radiation system.

Here, the printing apparatus provided by the present application is configured with the control system according to any one of the embodiments provided by the fourth aspect of the present application, so that monitoring of an abnormality occurring during printing can be realized to control a print job. The processing device 52 in the control system is connected with the shooting device 51, the processing device 52 is, for example, a software module configured in the control device 45, or an electronic device configured in communication connection with the control device 45, the processing device 52 is connected with the shooting device 51, and is configured to detect whether there is a printing defect target printing member according to a current solidified layer image and a corresponding slice image of a plurality of currently printed printing members, acquire a reference slice image of the plurality of printing members when it is detected that there is a printing defect in at least one printing member of the plurality of currently printed printing members, perform image processing on the reference slice image corresponding to the at least one printing member of the reference slice images of the plurality of printing members to obtain an outline of the at least one printing member, and generate a mask image according to the outline of the at least one printing member, wherein a region of the mask image corresponding to the outline of the at least one target printing member is an exposure-inhibited region. The processing device 52 may transmit the processing results to the control device 45 so that the control device 45 can control the energy radiation system 44 and the Z-axis driving mechanism 43 according to the mask image to realize the control of the printing process.

The present application further provides a computer device in a fifth aspect, please refer to fig. 28, which is a simplified block diagram of the computer device of the present application in one embodiment.

As shown in the figure, the computer device includes a storage device 61 and a processing device 62, where the storage device 61 is used to store at least one program, and the processing device 62 is connected to the storage device 61 and is used to execute and implement the 3D printing control method according to any one of the embodiments provided in the first aspect of the present application when the at least one program is executed.

In an embodiment, the storage 61 may include high speed random access memory, and may also include non-volatile memory, such as one or more magnetic disk storage devices, flash memory devices, or other non-volatile solid state storage devices. In certain embodiments, the storage 61 may also include memory remote from the one or more processors, such as network attached memory accessed via RF circuitry or external ports and a communications network, which may be the internet, one or more intranets, local area networks, wide area networks, storage area networks, and the like, or suitable combinations thereof. The storage device 61 controller may control access to the memory by other components of the apparatus, such as the CPU and peripheral interfaces.

In an embodiment, the processing means 62 is operatively coupled to the storage means 61 and/or a non-volatile storage device. More specifically, the processing device 62 may execute instructions stored in the storage device 61 and/or the non-volatile storage device to perform operations in the computing device, such as generating and/or transmitting image data to an electronic display. As such, processing device 62 may include one or more general-purpose microprocessors, one or more special-purpose processors, one or more field programmable logic arrays, or any combination thereof.

In some embodiments, the processing device 62 comprises an integrated circuit chip having signal processing capabilities; or comprise a general purpose processor which may be a microprocessor, or any conventional processor such as a central processing unit. For example, the Digital Signal Processor (DSP), Application Specific Integrated Circuit (ASIC), discrete gate or transistor logic device, discrete hardware component, may implement or execute the methods, steps, and logic blocks disclosed in the embodiments of the present application, for example, based on at least one program stored in the storage device 61, and when the at least one program is executed, the method for controlling 3D printing according to any one of the embodiments provided in the first aspect of the present application may be executed and implemented.

In some embodiments, the computer apparatus further includes a display whose functions are implemented by a graphics module in the electronic device and a display controller thereof, the graphics module including various known software components for rendering and displaying graphics on a touch screen. Note that the term "graphic" includes any object that may be displayed to a user, including but not limited to text, web pages, icons (e.g., user interface objects including soft keys), digital images, videos, animations and the like. The display screen is, for example, a touch screen, and provides both an output interface and an input interface between the device and the user. The touch screen controller receives/sends electrical signals from/to the touch screen. The touch screen then displays visual output to the user. This visual output may include text, graphics, video, and any combination thereof.

In a sixth aspect, the present application further provides a computer-readable/writable storage medium, which stores at least one program, and when the at least one program is executed, the at least one program implements the control method for 3D printing according to any one of the embodiments provided in the first aspect of the present application.

The functions of the control method for 3D printing provided in the first aspect of the present application may be stored in a computer-readable storage medium if they are implemented in the form of software functional units and sold or used as independent products. Based on such understanding, the technical solutions of the present application or portions thereof that substantially contribute to the prior art may be embodied in the form of a software product, which is stored in a storage medium and includes several instructions for causing a computer device (which may be a personal computer, a server, or a network device) to execute all or part of the steps of the methods described in the embodiments of the present application.

In the embodiments provided herein, the computer-readable and writable storage medium may include read-only memory, random-access memory, EEPROM, CD-ROM or other optical disk storage, magnetic disk storage or other magnetic storage devices, flash memory, a USB flash drive, a removable hard disk, or any other medium that can be used to store desired program code in the form of instructions or data structures and that can be accessed by a computer. Also, any connection is properly termed a computer-readable medium. For example, if the instructions are transmitted from a website, server, or other remote source using a coaxial cable, fiber optic cable, twisted pair, Digital Subscriber Line (DSL), or wireless technologies such as infrared, radio, and microwave, then the coaxial cable, fiber optic cable, twisted pair, DSL, or wireless technologies such as infrared, radio, and microwave are included in the definition of medium. It should be understood, however, that computer-readable-writable storage media and data storage media do not include connections, carrier waves, signals, or other transitory media, but are intended to be non-transitory, tangible storage media. Disk and disc, as used in this application, includes Compact Disc (CD), laser disc, optical disc, Digital Versatile Disc (DVD), floppy disk and blu-ray disc where disks usually reproduce data magnetically, while discs reproduce data optically with lasers.

In one or more exemplary aspects, the functions described in the computer program of the methods described herein may be implemented in hardware, software, firmware, or any combination thereof. When implemented in software, the functions may be stored on or transmitted over as one or more instructions or code on a computer-readable medium. The steps of a method or algorithm disclosed herein may be embodied in processor-executable software modules, which may be located on a tangible, non-transitory computer readable and writable storage medium. Tangible, non-transitory computer readable and writable storage media may be any available media that can be accessed by a computer.

The flowchart illustrations and block diagrams in the figures presented above of the present application illustrate the architecture, functionality, and operation of possible implementations of systems, methods and computer program products according to various embodiments of the present application. In this regard, each block in the flowchart or block diagrams may represent a module, segment, or portion of code, which comprises one or more executable instructions for implementing the specified logical function(s). It should also be noted that, in some alternative implementations, the functions noted in the block may occur out of the order noted in the figures. For example, two blocks shown in succession may, in fact, be executed substantially concurrently, or the blocks may sometimes be executed in the reverse order, depending upon the functionality involved. It will also be noted that each block of the block diagrams and/or flowchart illustration, and combinations of blocks in the block diagrams and/or flowchart illustration, can be implemented by special purpose hardware-based systems which perform the specified functions or acts, or combinations of special purpose hardware and computer instructions.

The above embodiments are merely illustrative of the principles and utilities of the present application and are not intended to limit the application. Any person skilled in the art can modify or change the above-described embodiments without departing from the spirit and scope of the present application. Accordingly, it is intended that all equivalent modifications or changes which can be made by those skilled in the art without departing from the spirit and technical concepts disclosed in the present application shall be covered by the claims of the present application.

Claims

1. A control method for 3D printing is characterized by comprising the following steps:

when detecting that at least one target printing component in a plurality of currently printed target printing components has a printing defect, acquiring reference slice images of the plurality of target printing components; the manner of acquiring the reference slice images of the plurality of target printing members includes at least one of: if the target printing piece is of a structure with the largest bottom or the largest top, using a first layer of slice image or a last layer of slice image corresponding to the target printing component as a reference slice image of the target printing component; if the target printing piece is in a straight-tube type or reducing type structure, using a current layer slice image corresponding to the target printing component as a reference slice image of the target printing component; and projecting a projection image obtained by projecting the target printing component and the related supporting body thereof as a reference slice image of the target printing component;

performing image processing on a reference slice image of the target printing components corresponding to the at least one target printing component to obtain the outline of the at least one target printing component;

generating a mask image from the profile of the at least one target printing member; the step of generating a mask image from the profile of the at least one target printing member comprises: transferring the outline of the at least one target printing component to a corresponding region in an existing mask image to obtain a mask image; a region in the mask image corresponding to the outline of the at least one target printing member is an exposure-inhibited region; and

performing a masking operation on the slice images of the plurality of target printing members using the mask image to perform a print job.

2. The method for controlling 3D printing according to claim 1, wherein the manner of detecting that at least one target printing component of a plurality of target printing components currently printed has a printing defect comprises the following steps:

acquiring current solidified layer images of a plurality of currently printed target printing components and slice images corresponding to the current solidified layer images; wherein the slice image comprises one or more slice contours;

for any target printing component, determining a target object from a current solidified layer image of the target printing component and a reference object from a slice image of the target printing component, and determining a matching result of the reference object and the target object based on a preset matching rule to determine whether the target printing component has a printing defect; wherein the target object is obtained by processing one or more curing contours in the current curing layer image, and the reference object is obtained by processing one or more slice contours included in the slice image.

3. The method of controlling 3D printing according to claim 2, wherein processing the one or more curing profiles in the current cured layer image comprises: judging one or more curing profiles and determining the deletion operation of the curing profiles based on the judgment result; processing the one or more slice profiles includes: one or more slice contours are judged and a pruning operation for the slice contours is determined based on the judgment result.

4. The method of controlling 3D printing according to claim 3, wherein the manner of determining the target object comprises the steps of:

determining one or more curing contours comprised by a target printing member contour in the current curing layer image;

determining whether the shape of each curing contour meets a preset specification; and

and deleting the curing profile determined to be not in accordance with the preset specification, and reserving the curing profile determined to be in accordance with the preset specification to obtain the target object.

5. The method of controlling 3D printing according to claim 3, wherein the manner of determining the reference object comprises the steps of:

determining whether the morphology of each slice contour in the slice image meets a preset specification; and

deleting the slice contour determined to be not in accordance with the preset specification, and reserving the slice contour determined to be in accordance with the preset specification to obtain the reference object.

6. The 3D printing control method according to claim 3, wherein the mode of determining the matching result of the reference object and the target object based on the preset matching rule comprises the following steps:

determining a slice contour in the reference object as a reference contour; and

and searching for a curing contour of which the deviation from the reference contour is smaller than a preset threshold value in the target object, and determining the searched curing contour as a target contour matched with the reference contour, or determining that the reference contour has printing defects when the curing contour is not searched.

7. The method for controlling 3D printing according to claim 6, further comprising a step of deleting the searched curing profile from the target object to search for a curing profile having a deviation from a next reference profile smaller than a preset threshold value in the updated target object.

8. The method for controlling 3D printing according to claim 6, wherein the manner of finding a cured profile in the target object having a deviation from a reference profile smaller than a preset threshold value comprises the steps of:

the reference contour is characterized as a reference coordinate point list, and a curing contour enabling the distance from each coordinate point in the reference coordinate point list to the curing contour to be smaller than a preset threshold value is searched in the target object; or

And characterizing each curing contour in the target object as a target coordinate point list, and searching for the curing contour of which the distance from each coordinate point in the target coordinate point list to the reference contour is smaller than a preset threshold value in the target object.

9. The method of controlling 3D printing according to claim 2, wherein the manner of determining the target object from the current solidified layer image includes the steps of:

denoising the current solidified layer image to obtain a target printing component outline image; and

determining a target object in the target printing member outline image.

10. The method for controlling 3D printing according to claim 9, wherein the means for denoising the current cured layer image comprises the steps of:

acquiring a printing background image in an actual printing environment, wherein the printing background image comprises an image in a forming chamber shot before solidification starts; and

and carrying out background correction on the current curing layer image based on the printing background image so as to realize denoising processing.

11. The method for controlling 3D printing according to claim 10, wherein the step of acquiring the printing background image includes:

the distance between the component platform and the shooting device in the printing equipment is determined so that the component platform in the image in the forming chamber acquired by the shooting device is in a fuzzy state.

12. The method of controlling 3D printing according to claim 11, wherein the manner of determining the distance between the component platform and the camera comprises at least one of:

when the transparency of the printing material is determined to be above a preset threshold value, adjusting the component platform to be out of the depth of field of the shooting device; and

and when the transparency of the printing material is smaller than the preset threshold value, adjusting the distance from the component platform to the printing reference surface to enable the component platform to be in a fuzzy state in the image in the forming chamber acquired by the shooting device.

13. The method of controlling 3D printing according to claim 10, wherein the means for performing background correction on the current cured layer image based on the printing background image includes any one of:

subtracting the gray value of the printing background image at each pixel point from the gray value of the current solidified layer image at each pixel point; and

subtracting the RGB values of the printing background image at the respective pixel points from the RGB values of the current cured layer image at the respective pixel points.

14. The method for controlling 3D printing according to claim 10, wherein the manner of acquiring the current cured layer image includes:

when the current solidified layer is close to or positioned in a printing reference surface of a forming chamber, shooting an image in the forming chamber to determine a current solidified layer image; or

When the current solidified layer is close to or positioned in a printing reference surface in the forming chamber, a plurality of images in the forming chamber are shot, and the images of the current solidified layer are subjected to average noise reduction to obtain an image of the current solidified layer.

15. The 3D printing control method according to claim 10, wherein the print background image is acquired in a manner including:

shooting an image in the forming chamber before curing is started to determine a printing background image; or

And shooting a plurality of images in the forming chamber before curing is started and carrying out average noise reduction on the plurality of images to obtain a printing background image.

16. The method of controlling 3D printing according to claim 2, further comprising a step of subjecting the current solidified layer image or the slice image to perspective transformation processing to obtain a target object and a reference object characterized by the same coordinate system.

17. The method for controlling 3D printing according to claim 16, wherein the same coordinate system is a projection coordinate system of an energy radiation system in a printing apparatus or an optical coordinate system of a camera, and the determining of the mapping relationship by determining the mapping relationship of the current solidified layer image and the slice image to perform perspective transformation processing on the current solidified layer image or the slice image comprises the following steps:

projecting a plurality of calibration points on the printing reference surface, and recording projection coordinates of the plurality of calibration points in a projection coordinate system of the energy radiation system;

enabling the shooting device to acquire an image of the printing reference surface to determine image coordinates of a plurality of calibration points in an optical coordinate system of the shooting device; and

and calculating and determining the mapping relation between the current solidified layer image and the slice image based on the projection coordinates and the image coordinates.

18. The method of controlling 3D printing according to claim 17, wherein determining the position of the plurality of calibration points projected on the printing reference plane comprises at least one of:

determining a plurality of calibration point positions projected on a printing reference surface based on the relation between the calibration point positions and the precision of the calibration point image projected by the energy radiation system; and

19. The control method of 3D printing according to claim 2 or 16, further comprising a step of determining an ROI region of the current cured layer image to determine the target object in the ROI region of the current cured layer image.

20. The 3D printing control method according to claim 1, wherein the image processing of the reference slice image of the plurality of target printing members corresponding to the at least one target printing member to obtain the contour of the at least one target printing member comprises the following steps:

acquiring a mark point positioned in a reference slice image of the at least one target printing component; and

and performing image processing on the reference slice image of the at least one target printing component according to the mark points to obtain the outline of the at least one target printing component.

21. The method of controlling 3D printing according to claim 20, wherein the capturing of the marker points located within the reference slice image of the at least one target printing member comprises:

one or more mark points are obtained in the reference slice image of at least one target printing component with the detected printing defects in a manual mode or a detection program.

22. The method for controlling 3D printing according to claim 20, wherein the step of performing image processing on the reference slice image corresponding to the at least one target printing component according to the mark points to obtain the contour of the at least one target printing component comprises the steps of:

and performing connected domain calculation on the reference slice image of the corresponding at least one target printing component according to the mark points to obtain the outline of the at least one target printing component.

23. A control system for 3D printing, comprising:

the acquisition module is used for acquiring reference slice images of a plurality of target printing components when detecting that at least one target printing component in the plurality of target printing components which are printed currently has a printing defect; the mode of acquiring the reference slice image by the acquisition module comprises at least one of the following modes: if the target printing piece is of a structure with the largest bottom or the largest top, using a first layer of slice image or a last layer of slice image corresponding to the target printing component as a reference slice image of the target printing component; if the target printing piece is in a straight-tube type or reducing type structure, using a current layer slice image corresponding to the target printing component as a reference slice image of the target printing component; and projecting a projection image obtained by projecting the target printing component and the related support body thereof as a reference slice image of the target printing component;

the processing module is used for carrying out image processing on the reference slice image of the at least one target printing component in the reference slice images of the plurality of target printing components so as to obtain the outline of the at least one target printing component; and generating a mask image according to the profile of the at least one target printing component to cause the 3D printing device to mask slice images of the plurality of target printing components based on the mask image to perform a print job, wherein the generating the mask image according to the profile of the at least one target printing component comprises: transferring the outline of the at least one target printing component to a corresponding region in an existing mask image to obtain a mask image; the region of the mask image corresponding to the outline of the at least one target printing member is an exposure-inhibited region.

24. The control system of 3D printing of claim 23, further comprising a detection module to detect a plurality of target printing members currently being printed to determine whether any of the target printing members have a print defect.

25. A control system is applied to a 3D printing device, and the 3D printing device comprises: a forming chamber, an energy radiation system, and a component platform to which a cured layer selectively cured by the energy radiation system is accumulated, wherein the control system comprises:

the shooting device is used for shooting images in the forming chamber to obtain current solidified layer images of a plurality of currently printed target printing components; and

the processing device is connected with the shooting device and used for detecting whether a target printing component with a printing defect exists or not according to a current solidified layer image and a corresponding slice image of a plurality of currently printed target printing components, acquiring reference slice images of the plurality of target printing components when the condition that at least one target printing component in the plurality of currently printed target printing components has the printing defect is detected, performing image processing on the reference slice image corresponding to the at least one target printing component in the reference slice images of the plurality of target printing components to obtain the outline of the at least one target printing component, and generating a mask image according to the outline of the at least one target printing component;

the manner of acquiring the reference slice images of the plurality of target printing members includes at least one of: if the target printing piece is of a structure with the largest bottom or the largest top, using a first layer of slice image or a last layer of slice image corresponding to the target printing component as a reference slice image of the target printing component; and if the target printed matter is in a straight cylinder type or a reduction type structure, using the current layer slice image corresponding to the target printing component as a reference slice image of the target printing component; projecting a target printing component and a related supporting body thereof to obtain a projection image as a reference slice image of the target printing component;

said generating a mask image from the profile of the at least one target printing member comprises: transferring the outline of the at least one target printing component to a corresponding area in an existing mask image to obtain a mask image; an area of the mask image corresponding to the outline of the at least one target printing member is an exposure inhibited area.

26. A3D printing apparatus, comprising:

a container for holding a photocurable material to be cured;

an energy radiation system for selectively curing the light-curable material according to the data of the received slice image to form a cured layer;

a member platform in the container for cumulatively attaching the solidified layer;

the Z-axis driving mechanism is connected with the component platform and is used for adjusting the distance from the component platform to the printing reference surface; the control system according to claim 25, configured to detect a plurality of target printing members currently being printed and generate a mask image corresponding to at least one target printing member when a print defect is detected in the at least one target printing member, wherein a region in the mask image corresponding to an outline of the at least one target printing member is an exposure-inhibited region; and

and the control device is connected with the Z-axis driving mechanism and the energy radiation system and is used for controlling the Z-axis driving mechanism and the energy radiation system according to the mask image.

27. A computer device, comprising:

storage means for storing at least one program; and

processing means connected to the storage means for running the at least one program to execute and implement the control method of 3D printing as claimed in any one of claims 1 to 22.

28. A computer-readable storage medium, in which at least one program is stored, the at least one program, when executed by a processor, implementing a method of controlling 3D printing according to any one of claims 1 to 22.