WO2021093476A1

WO2021093476A1 - 3d object slice layer printing method, 3d object printing method and printing device

Info

Publication number: WO2021093476A1
Application number: PCT/CN2020/118046
Authority: WO
Inventors: 向东清
Original assignee: 珠海赛纳三维科技有限公司
Priority date: 2019-11-15
Filing date: 2020-09-27
Publication date: 2021-05-20
Also published as: CN110815825B; CN110815825A

Abstract

A 3D object slice layer printing method, and a 3D object printing method and printing device. The 3D object slice layer printing method comprises: obtaining layer image data of a slice layer of an object to be printed; determining the limit radial distance between the slice layer and the center of a rotating support platform (1) according to the layer image data, wherein the limit radial distance comprises the minimum radial distance and/or the maximum radial distance; determining the boundary position of the uniform radial movement of a print head (2) according to an arc formed by using the center of the rotating support platform (1) as the center and the limit radial distance as the radius; and obtaining layer printing data of the slice layer and controlling the print head (2) to perform printing actions according to the boundary position and the layer printing data to obtain a layer printing result. The printing method and printing device can effectively reduce the ineffective movement area of the print head, improve the formation efficiency of the 3D object to be printed, and reduce the operating cost of a printer.

Description

3D object slice layer printing method, 3D object printing method and printing device

This application claims the priority of a Chinese patent application filed with the Chinese Patent Office on November 15, 2019, the application number is 201911118166.2, and the invention title is "3D object slice layer printing method, 3D object printing method and printing device". The entire content is incorporated into this application by reference.

Technical field

This application relates to the technical field of 3D object molding, and in particular to a method for printing a slice layer of a 3D object, a method for printing a 3D object, and a printing device.

Background technique

Rapid prototyping technology is also called rapid prototyping manufacturing technology or additive manufacturing technology. Its basic principle is based on the 3D model slices to form multiple slice layers, and then after data processing, the 3D is made by layer-by-layer (ie slice-by-layer) processing and accumulation. object.

The existing rotating 3D printer (such as a rotating 3D printer with a ring-shaped support platform) includes a rotating support platform, a print head, a carriage, a slide rail and a control device. After printing starts, the rotating support platform has been rotating at a constant speed, and the carriage In the area where the rotary support platform is located, move from the outer diameter position of the rotary support platform to the inner diameter position along the slide rail at a constant speed, then decelerate and then accelerate in the opposite direction. In the area where the rotary support platform is located, the print head moves at a uniform speed from the inner diameter position to the outer diameter position.径位置。 Path location. Since the print head is always moving at a constant speed in the entire area of the rotating support platform, when the print area of the object to be printed is small and cannot cover the area in the radial direction of the support platform, for example, place the object to be printed close to the outer diameter. Or near the position of the inner diameter, the print head must move uniformly in the radial direction from the outer radial to the inner diameter and/or from the inner radial to the outer diameter. As a result, the ineffective printing area of the print head increases and the object to be printed is formed. The efficiency decreases and the operating cost of the printer increases.

Application content

In order to overcome the above-mentioned drawbacks, this application provides a method for printing a slice layer of a 3D object, a method for printing a 3D object, and a printing device, which can effectively reduce the ineffective movement area of the print head, improve the molding efficiency of the 3D object to be printed, and reduce the operation of the printer cost.

In the first aspect, an embodiment of the present application provides a method for printing a slice layer of a 3D object, and the method includes:

Acquiring the layer image data of the slice layer of the object to be printed;

Determining the limit radial distance between the slice layer and the center of the rotating support platform according to the layer image data, wherein the limit radial distance includes a minimum radial distance and/or a maximum radial distance;

Determine the boundary position of the uniform radial movement of the print head according to an arc formed by taking the center of the rotating support platform as the center and the limit radial distance as the radius;

Obtain the layer printing data of the slice layer, and control the print head to perform a printing action according to the boundary position and the layer printing data to obtain a layer printing result.

Optionally, the determining the limit radial distance between the slice layer and the center of the rotating support platform according to the layer image data includes:

Position the multiple pixels to be printed in the layer image data through a preset polar coordinate system to obtain the coordinates (r _i , θ _i ) of the multiple pixels to be printed, where r _i represents the ith The distance between each pixel to be printed and the pole, θ _i represents the polar angle of the i-th pixel to be printed;

The limit radial distance between the slice layer and the center of the rotating support platform is determined according to _{the coordinates (r i} , θ _i ) of the plurality of pixels to be printed.

Optionally, the polar coordinate system is a polar coordinate system with the center of the rotating support platform as a pole.

Optionally, before the determining the limit radial distance between the slice layer and the center of the rotating support platform according to the layer image data, the method further includes:

_{Obtain the coordinates (x 0} , y ₀ ) of the center of the rotating support platform in the preset rectangular coordinate system;

_{Acquire the coordinates (x mn} , y _mn ) of at least one pixel to be printed in the layer image data in the preset rectangular coordinate system; wherein, the rectangular coordinate system is a coordinate system whose horizontal direction is the X axis .

Obtaining the coordinates of a plurality of pixels to be printed in the layer image data according to the coordinates of the at least one pixel to be printed in the layer image data in the rectangular coordinate system;

The limit radial distance between the slice layer and the center of the rotating support platform is determined according to the coordinates of the plurality of pixels to be printed and the coordinates of the center of the rotating support platform.

Optionally, the acquiring the layer printing data of the slice layer, and controlling the print head to perform a printing action according to the boundary position and the layer printing data to obtain the layer printing result includes:

_{Acquiring the first relative coordinates (x mn-} x ₀ , y _mn -y ₀ ) of the at least one pixel to be printed relative to the center of the rotating support platform;

Acquiring layer printing data of the slice layer;

According to the first relative coordinates, the boundary position, and the layer printing data, the print head is controlled to perform a printing action to obtain a layer printing result.

Optionally, the pixels to be printed include at least one of pixels that require inkjet printing and pixels that do not require inkjet printing.

The limit radial distance between the slice layer and the center of the rotating support platform is determined according to the coordinates of the pixel points that need inkjet printing among the plurality of pixels to be printed and the coordinates of the center of the rotating support platform.

Obtaining the smallest circumscribed rectangle of the pixel that needs inkjet printing among the plurality of pixels to be printed in the layer image data;

_{Obtain the coordinates (x mn} ′, y _mn ′) of at least one pixel to be printed within the minimum circumscribed rectangle and the second relative coordinate (x mn ′, y mn ′) of the at least one pixel to be printed relative to the center of the rotating support platform ( x _mn'- x ₀ , y _mn' -y ₀ );

Extracting data of the layer image data within the minimum circumscribed rectangle range as layer printing data;

According to the second relative coordinates, the boundary position, and the layer printing data, the print head is controlled to perform a printing action to obtain a layer printing result.

Optionally, at least one pixel to be printed in the range of the smallest circumscribed rectangle is at least one vertex of the smallest circumscribed rectangle; the second pixel to be printed relative to the center of the rotating support platform The relative coordinate is the second relative coordinate of the at least one vertex relative to the center of the rotating support platform.

Optionally, the limit radial distance includes a minimum radial distance, and the printing head is determined to be a radial uniform movement of the print head based on an arc formed by taking the center of the rotating support platform as a center and the limit radial distance as a radius The boundary position of includes:

Determining an arc formed by taking the center of the rotating support platform as the center and the minimum radial distance as the radius as the first boundary position of the uniform radial movement of the print head;

The outer circumference of the rotating support platform is determined as the second boundary position of the uniform radial movement of the print head.

Optionally, the limit radial distance includes a maximum radial distance, and the radial uniform motion of the print head is determined according to an arc formed by taking the center of the rotating support platform as the center and the limit radial distance as the radius. The boundary position of includes:

Determining the inner circumference of the rotating support platform as the first boundary position of the print head moving at a uniform speed in the radial direction;

A circular arc formed with the center of the rotating support platform as the center and the maximum radial distance as the radius is determined as the second boundary position of the uniform radial movement of the print head.

Optionally, the limit radial distance includes a minimum radial distance and a maximum radial distance; the printing head is determined based on an arc formed by taking the center of the rotating support platform as the center and the radial distance as the radius. The boundary position of radial uniform motion includes:

Optionally, before the acquiring the layer image data of the slice layer of the object to be printed, the method further includes:

Slice and layer the digital model of the object to be printed to obtain multiple slice layers and layer image data of the multiple slice layers.

During the printing process, set the rotation speed of the rotating support platform to a preset value; or

Set the rotation speed value of the rotating support platform to change in an inverse proportional relationship with the maximum radial distance of the slice layer currently printed; and/or

The rotation speed value of the rotating support platform is set to change in a proportional relationship with the speed of the uniform radial movement of the print head.

Optionally, the object to be printed includes a physical structure part, or a physical structure part and a non-physical structure part.

Optionally, the non-physical structure part includes at least one of a supporting structure part and an extended structure part.

In a second aspect, an embodiment of the present application provides a method for printing a 3D object. The method includes: controlling the rotation speed of the rotating support platform to a first preset value, and printing the result by using the above-mentioned printing method of the slice layer of the 3D object The layer printing result of the first slice layer; afterwards, the rotation speed of the rotating support platform is controlled to be the second preset value, and the printing is performed according to the layer printing data of the Nth slice layer, where N is a positive value greater than 1. Integer, the layer printing results obtained by printing are superimposed layer by layer to obtain a 3D object; the second preset value is greater than or equal to the first preset value.

In a third aspect, an embodiment of the present application provides a 3D object printing device, including:

A data processing module, configured to slice and layer the object to be printed to obtain multiple slice layers and layer image data, and process the layer image data, and the data processing module is connected to the control component;

A print head for jetting printing materials, the print head is connected with the control component;

A rotating support platform for supporting the layer printing result of the object to be printed; and

The control component is used for controlling the rotating support platform and the print head to perform a printing action using the above-mentioned printing method of the slice layer of the 3D object.

In this solution, during the 3D object rotation printing process, by acquiring the layer image data of the slice layer of the object to be printed, the limit radial distance between the slice layer and the center of the rotating support platform is determined, so as to determine the uniform radial movement of the print head The boundary position reduces the uniform motion area of the print head for ineffective printing, improves the printing efficiency of the slice layer, and further improves the molding efficiency of 3D objects and reduces the operating cost of the printer.

Description of the drawings

The application will be further described below in conjunction with the drawings and embodiments.

FIG. 1 is a schematic structural diagram of a 3D object printing apparatus provided by an embodiment of the application;

2a-2c are schematic diagrams of the slice layered structure of a digital model of a 3D object in an embodiment of the application;

3 is a schematic flowchart of a method for printing a slice layer of a 3D object according to Embodiment 1 of the application;

4 is a schematic diagram of the relative positions of all slices of layer image data on the virtual supporting platform in the polar coordinate system in Embodiment 1 of the application;

5a to 5c are schematic diagrams of the uniform radial movement area of the print head in the polar coordinate system in Embodiment 1 of the present application;

6 is a schematic flowchart of a method for printing a slice layer of a 3D object according to Embodiment 2 of the present application;

7 is a schematic diagram of the relative position of the layer image data of all slices on the virtual support platform in the rectangular coordinate system in Embodiment 2 of the application;

FIG. 8 is a schematic diagram of the uniform radial movement area of the print head in the Cartesian coordinate system in Embodiment 2 of the present application.

9 is a schematic flowchart of a method for printing a slice layer of a 3D object provided in Embodiment 3 of the application;

10 is a schematic diagram of the uniform radial movement area of the print head in the Cartesian coordinate system in Embodiment 3 of the application;

11 is a schematic diagram of a 3D object printing method provided in Embodiment 4 of the application;

FIG. 12 is a schematic diagram of a method for printing a 3D object according to Embodiment 5 of the present application.

Specific embodiment

In order to better understand the technical solutions of the present application, the embodiments of the present application will be described in detail below with reference to the accompanying drawings.

It should be clear that the described embodiments are only a part of the embodiments of the present application, rather than all of the embodiments. Based on the embodiments in this application, all other embodiments obtained by a person of ordinary skill in the art without creative work shall fall within the protection scope of this application.

The terms used in the embodiments of the present application are only for the purpose of describing specific embodiments, and are not intended to limit the present application. The singular forms of "a", "the" and "the" used in the embodiments of the present application and the appended claims are also intended to include plural forms, unless the context clearly indicates other meanings.

It should be understood that the term "and/or" used in this text is only an association relationship describing the associated objects, indicating that there can be three types of relationships, for example, A and/or B can mean that A alone exists, and both A and A exist at the same time. B, there are three cases of B alone. In addition, the character "/" in this text generally indicates that the associated objects before and after are in an "or" relationship.

Please refer to Figure 1. Figure 1 is a 3D object printing device provided by an embodiment of the present application, which includes a rotating support platform 1, a print head 2, a carriage, a sliding rail 3, a control component 4, and a data processing module 5. , The print head 2 is installed on the carriage.

The rotating support platform 1 is used to support the printed 3D object, and the shape of the rotating support platform 1 can be a circle, a circular ring, a sector, or other shapes. During the 3D object printing process, the rotating support platform 1 and the printing head 2 perform relative rotation movement. In this embodiment, the rotating support platform 1 has a circular ring shape, and the rotating support platform 1 makes a circular motion relative to the print head 2.

The type and number of print heads 2 in this application are not limited, and may include at least one print head 2, and the print head 2 may be a single-channel print head or a multi-channel print head. The control component 4 controls the print head 2 to move on the slide rail 3; the extension direction of the slide rail 3 passes through the center O of the rotating support platform 1.

Before the 3D object is printed, the digital model of the 3D object to be printed is imported into the data processing module 5. The data processing module 5 may be slicing software, for example. In the slicing software, the digital model of the object to be printed is set in a virtual support platform. Understandably, the virtual support platform is used to simulate the rotating support platform 1 of the printing device. The data processing module 5 is used to slice and layer the digital model of the object to be printed to obtain multiple slice layers and layer image data of each slice layer.

The 3D object to be printed in this application includes a physical structure part, or includes a physical structure part and a non-physical structure part. The non-physical structure part includes at least one of a supporting structure part and an extended structure part. The supporting structure part refers to the structure that supports the physical structure part during the printing process of the physical structure part, and the extended structure part refers to the structure located at the periphery of the physical structure part and/or the supporting structure during the printing process of the physical structure part.

For details, refer to Figs. 2a to 2c, which are schematic diagrams of the slice layered structure of the digital model of the 3D object in this application. The digital model of the 3D object in Fig. 2a only includes the physical structure part 10, which is composed of slice layers L11, L12...L1(f- 1) L1f is superimposed; the digital model of the 3D object in Figure 2b includes a solid structure part 20 and a support structure part 21, which is formed by superimposing slice layers L21, L22...L2(f-1), L2f, the 3D object in Figure 2c The digital model includes a solid structure part 30, a support structure part 31, and an extended structure part 32, which are formed by superimposing slice layers L31, L32...L3(f-1), L3f; where f is a positive integer, and the specific value of f is the same as The height of the 3D object is related to the thickness of the slice layer.

After the 3D object printing starts, the rotating support platform 1 has been rotating at a constant speed, and the print head 2 is located in the area where the rotating support platform 1 is located (as shown in the shaded area in Figure 1), and is located along _{the outer diameter R 1 of the rotating support platform 1.} The slide rail 3 moves at a constant speed to the _{position of the inner diameter R 0} , then decelerates and then accelerates in the reverse direction, and moves at a constant speed from the position _{of the inner diameter R 0 of the} _{rotating support platform 1 to the position of the outer diameter R 1} .

Understandably, when the print area of the 3D object to be printed cannot cover the area in the radial direction of the rotating support platform 1 (as shown in the shaded area in Figure 1), for example, the object to be printed is placed near the outer diameter R ₁ Or close to _{the position of the inner diameter R 0} , the print head 2 must move in the radial direction from the outer diameter R ₁ to the inner diameter R ₀ at a constant speed and/or from the inner diameter R ₀ to the outer diameter R _{1 to} move at a constant speed, so that the print head The invalid printing area of 2 increases, the molding efficiency of the object to be printed decreases, and the operating cost of the printer increases.

In the actual printing process, the rotation speed of the rotating support platform 1, the uniform moving speed of the print head 2 and the ejection frequency of the print head 2 match, so as to meet the printing accuracy of the object to be printed.

Please continue to refer to FIG. 3. FIG. 3 shows a method for printing a slice layer of a 3D object according to an embodiment of the present application. The method includes:

Step S01, acquiring the layer image data of the slice layer of the object to be printed;

Step S02: Determine the limit radial distance between the slice layer and the center of the rotating support platform according to the layer image data, where the limit radial distance includes the minimum radial distance and/or the maximum radial distance;

Step S03: Determine the boundary position of the uniform radial movement of the print head according to an arc formed by taking the center of the rotating support platform as the center and the limit radial distance as the radius;

Step S04: Obtain the layer printing data of the slice layer, and control the print head to execute the printing action according to the boundary position and the layer printing data to obtain the layer printing result.

In this solution, in the 3D rotating printing process, by acquiring the layer image data of the slice layer of the object to be printed, the limit radial distance between the slice layer and the center of the rotating support platform 1 is determined, so as to determine the uniform radial movement of the print head 2 The boundary position of the print head 2 reduces the uniform motion area of the ineffective printing of the print head 2 and improves the printing efficiency of the slice layer, thereby improving the molding efficiency of the 3D object, and reducing the operating cost of the printer.

The specific technical solution of the method for printing a slice layer of a 3D object provided in Embodiment 1 will be described in detail below.

Before step S01, the method further includes:

The digital model of the object to be printed is sliced and layered to obtain multiple slice layers and layer image data of the multiple slice layers.

Specifically, the digital model of the object to be printed can be converted into data in a data format that can be recognized by the data processing module 5 (slicing software). The data format recognized by the slicing software includes STL data format, PLY data format, or WRL data Format etc.

Step S01: Obtain the layer image data of the slice layer of the object to be printed.

In one embodiment, the digital model of the object to be printed is layered slice by slice, and the layer image data corresponding to each slice layer is obtained one by one. In other embodiments, after performing all the slice layers on the digital model of the object to be printed, all layer image data corresponding to all slice layers are acquired.

The layer image data of each slice layer includes a plurality of pixels to be printed, and the pixels to be printed include at least one of pixels that need inkjet printing and pixels that do not need inkjet printing.

Step S02: Determine the limit radial distance between the slice layer and the center of the rotating support platform according to the layer image data, where the limit radial distance includes the minimum radial distance and/or the maximum radial distance.

Fig. 4 is a schematic diagram of the relative position of the layer image data of all slices on the virtual support platform 1'in the polar coordinate system in the embodiment 1 of the present application. In the polar coordinate system, the slice software slices the digital model of the 3D object to obtain multiple slice layers and the layer image data of each slice layer. The layer image data 6 of one slice layer is located on the virtual support platform 1'in the slice software , The center of the virtual support platform 1'and the pole of the polar coordinate are at the same point O, and OX is the polar axis.

It is understandable that the virtual support platform 1'is used to simulate the rotating support platform 1 of the printing device, and the center coordinates of the virtual support platform 1'are the same as the center coordinates of the rotating support platform.

Further, the specific steps of step S02 include:

The plurality of layers of image data in the slice layer pixel to be printed by the predetermined polar coordinate system is positioned, to obtain the coordinates of a plurality of pixels to be printed (r _{_i,} θ _i), wherein, R & lt _i denotes the i th The distance between the pixel to be printed and the pole, θ _i represents the polar angle of the i-th pixel to be printed;

(R _{_i,} θ _i) determine the limiting radial distance from the center of rotation of the slice layer and the support platform from the coordinates of the plurality of pixels to be printed.

In this embodiment, the polar coordinate system is a polar coordinate system with the center of the rotating support platform as the pole.

Referring to FIGS. 5a ~ 5c, FIG. 5a ~ 5c in Example 1 is a schematic view of the first embodiment of the present application area radially uniform motion printed polar coordinate system, the coordinates of the position to be printed on the 6 pixels is represented as a layer image data (r _i , Θ _i ), since the center of the virtual support platform 1'and the pole of the polar coordinate are at the same point O, therefore, the distance from the pixel to be printed to the center of the virtual support platform 1'is equal to r _i , by comparing r of different pixels to be printed Values can get the maximum value r _max and the minimum value r _min .

For example, it can be seen from Figure 5a that the distance from the pixel point a to be printed to the center O is the minimum radial distance r _min , and the distance from the pixel point b to be printed to the center O is the maximum radial distance r _max . The distance from c to the center O lies between the maximum value and the minimum value.

Step S03: Determine the boundary position of the uniform radial movement of the print head according to an arc formed by taking the center of the rotating support platform as the center and the limit radial distance as the radius.

As shown in Figure 5a, step S03 includes:

_{Determine the arc R 2} formed by the center of the rotating support platform as the center and the minimum radial distance as the radius as the first boundary position of the uniform radial movement of the print head;

_{The arc R 3} formed with the center of the rotating support platform as the center and the maximum radial distance as the radius is determined as the second boundary position of the uniform radial movement of the print head.

The annular area 51 formed between the arc R ₂ and the arc R ₃ is the radial uniform movement area of the print head.

Specifically, when the print head performs bidirectional inkjet printing in the radial direction, when the print head _{moves from the outer circumference R 1 to the} inner circumference R _{0 of the} rotating support platform, the second boundary position (that is, the arc R ₃ ) is when the print head is at The starting position of the uniform movement in the radial direction, and the first boundary position (that is, the arc R ₂ ) is the end position of the uniform movement of the print head in the radial direction. When the print head moves from the inner circumference R _{0 of the} support platform to the outer circumference R ₁ , the first boundary position (that is, the arc R ₂ ) is the starting point of the print head moving at a constant speed in the radial direction, and the second boundary position (that is, the arc R ₃ ) is the end position of the print head moving at a constant speed in the radial direction.

Optionally, when the print head performs only one-way inkjet printing in the radial direction, when the print head _{moves from the outer circumference R 1 to the} inner circumference R _{0 of the} rotating support platform, the second boundary position (that is, the arc R ₃ ) is only It is the starting position of the uniform movement of the print head in the radial direction, and the first boundary position (ie, the arc R ₂ ) is only the end position of the uniform movement of the print head in the radial direction.

Optionally, when the print head performs only one-way inkjet printing in the radial direction, when the print head _{moves from the inner circumference R 0 of the} support platform to the outer circumference R ₁ , the first boundary position (ie, the arc R ₂ ) is only The starting position of the print head moving at a constant speed in the radial direction, and the second boundary position (ie, the arc R ₃ ) is only the ending position of the printing head moving at a constant speed in the radial direction.

As shown in Fig. 5b, Fig. 5b is a schematic diagram of another uniform radial movement area of the print head when printing the slice layer in the polar coordinate system in Embodiment 1 of the present application. Step S03 includes:

The outer circumference R _{1 of the} rotating support platform is determined as the second boundary position of the uniform radial movement of the print head.

As shown in Fig. 5b, _{the annular area 52 formed between the arc R 2} and the outer circumference R ₁ is the radial uniform movement area of the print head.

Specifically, when the print head performs bidirectional inkjet printing in the radial direction, when the print head _{moves from the outer periphery R 1 of the} rotating support platform to the inner periphery R ₀ , the outer periphery R ₁ of the rotating support platform is the uniform speed of the print head in the radial direction. The starting point of the movement, the first boundary position (that is, the arc R ₂ ) is the end position of the print head moving at a constant speed in the radial direction; when the print head moves from the inner circumference R _{0 of the} rotating support platform to the outer circumference R ₁ , the first boundary The position (that is, the arc R ₂ ) is the starting position of the uniform movement of the print head in the radial direction, and the outer circumference R ₁ of the rotating support platform is the end position of the uniform movement of the print head in the radial direction.

When the print head performs only one-way inkjet printing in the radial direction, when the print head _{moves from the outer periphery R 1 of the} rotating support platform to the inner periphery R ₀ , the outer periphery R _{1 of the} rotating support platform is only the print head at a constant speed in the radial direction The starting position of the movement, the first boundary position (that is, the arc R ₂ ) is the ending position of the uniform movement of the print head in the radial direction.

When the print head performs only one-way inkjet printing in the radial direction, when the print head _{moves from the inner circumference R 0 of the} support platform to the outer circumference R ₁ , the first boundary position (that is, the arc R ₂ ) is only when the print head is in the radial direction. The starting position of the uniform movement in the direction, the outer circumference R _{1 of the} rotating support platform is only the end position of the uniform movement of the print head in the radial direction.

As shown in Fig. 5c, Fig. 5c is a schematic diagram of another uniform radial movement area of the print head when printing the slice layer in the polar coordinate system in Embodiment 1 of the present application. Step S03 includes:

Determine the inner circumference R _{0 of the} rotating support platform as the first boundary position of the uniform radial movement of the print head;

As shown in Fig. 5c, _{the annular area 53 formed between the circular arc R 3} and the inner circumference R _{0 is} an area where the print head moves at a constant speed in the radial direction.

Specifically, when the print head performs bidirectional inkjet printing in the radial direction, when the print head _{moves from the outer circumference R 1 to the} inner circumference R _{0 of the} rotating support platform, the second boundary position (that is, the arc R ₃ ) is when the print head is at The starting position of the uniform movement in the radial direction, the inner circumference R ₀ of the rotating support platform is the end position of the uniform movement of the print head in the radial direction; when the print head moves from the inner circumference R _{0 of the} rotating support platform to the outer circumference R ₁ , The inner circumference R ₀ of the rotating support platform is the start position of the uniform movement of the print head in the radial direction, and the second boundary position (ie, the arc R ₃ ) is the end position of the uniform movement of the print head in the radial direction.

When the print head performs only one-way inkjet printing in the radial direction, when the print head _{moves from the outer circumference R 1 to the} inner circumference R _{0 of the} rotating support platform, the second boundary position (ie, the arc R ₃ ) is only when the print head is at The starting position of the uniform movement in the radial direction, the inner circumference R ₀ of the rotating support platform is the end position of the uniform movement of the print head in the radial direction.

When the print head performs only one-way inkjet printing in the radial direction, when the print head _{moves from the inner circumference R 0 of the} support platform to the outer circumference R ₁ , the inner circumference R _{0 of the} rotating support platform is only the uniform speed of the print head in the radial direction The starting position of the movement and the second boundary position (that is, the arc R ₃ ) is only the end position of the uniform movement of the print head in the radial direction.

The layer printing data of the slicing layer includes data for controlling whether at least one channel of the print head performs ink ejection. In this application, at least one material or at least one color is ejected through at least one channel of the print head. For example, "0" means no inkjet printing is required, and "1" means inkjet printing is required. During the printing process, when the print head moves to the "0" position, the print head does not perform inkjet printing, and when the print head moves to the "1" position, the print head performs inkjet printing. Those skilled in the art understand that the print head is in the "0" position. In the 1" position, either the molding material or the supporting material can be sprayed, depending on the model to be printed.

The layer print data of the slice layer in this application can use various data processing methods known in the art to process the layer image data of the slice layer to obtain the layer print data of the slice layer. There is no restriction here.

The

uniform movement area

51 or 52 or 53 of the print head in this embodiment 1 is smaller than the annular area of the rotating support platform 1. Therefore, the uniform movement area of the print head for ineffective printing is reduced, and the printing efficiency of a single slice layer is improved, thereby increasing It improves the molding efficiency of 3D objects and reduces the operating cost of the printer.

Further, the method for printing the slice layer further includes: during the printing process, setting the rotation speed of the rotating support platform to a preset value; or

Set the rotation speed value of the rotating support platform to change in inverse proportion to the maximum radial distance of the currently printed slice layer; and/or

Set the rotation speed of the rotating support platform to change in direct proportion to the speed of the uniform radial movement of the print head.

It is understandable that the rotating support platform 1 rotates at a constant speed during the printing of a single slice layer, and the rotation speed value of the rotating support platform 1 can be a preset value set previously (for example, 0.5r/s, that is, the rotating support platform every second Rotate 0.5 revolutions).

The rotation speed value of the rotating support platform 1 may also change in an inversely proportional relationship _{with the maximum radial distance r max.} Specifically, the linear velocity of the circumference of the rotary support platform is V, V=Rω, R is the outer radius of the rotary support platform, and ω is the rotation speed value of the support platform. In the printing process of a single slice layer, ω is a certain value. _{When the maximum radial distance r max is} less than R during the printing of the slice layer, the rotation speed ω of the rotating support platform can be increased so that the linear velocity of the arc L ₃ _{corresponding to the maximum radial distance r max} is equal to V.

Further, in the printing process of a single slice layer, the radial distance of the annular area formed by the first boundary position and the second boundary position is constant, ω is the rotation speed value of the support platform, when the rotation speed of the rotation support platform When the value ω increases, the speed of the uniform radial movement of the print head also increases.

In Example 1 of the present application _{, the rotation speed value of the rotating support platform is adjusted according to the maximum radial distance r max} , and the uniform radial movement speed of the print head is adjusted according to the rotation speed value of the rotating support platform. As the rotation speed of the rotating support platform increases, The speed of the uniform radial movement of the print head increases.

It is understandable that adjusting the rotation speed of the rotating support platform according to the limit radial distance of the print head at a uniform radial movement can further improve the printing efficiency of the slice layer, improve the molding efficiency of the object to be printed, and reduce the operating cost of the printer.

The specific technical solution of the method for printing a slice layer of a 3D object provided in the second embodiment will be described in detail below.

FIG. 6 is a schematic flowchart of a method for printing a slice layer of a 3D object according to Embodiment 2 of the application. As shown in FIG. 6, the difference between Embodiment 2 and Embodiment 1 is:

After step S01, the method for printing the slice layer further includes:

_{Step S11, obtain the coordinates (x 0} , y ₀ ) of the center of the rotating support platform in the preset rectangular coordinate system; obtain the coordinates (x 0, y 0) of at least one pixel to be printed in the layer image data in the preset rectangular coordinate system _mn , y _mn ); Among them, the rectangular coordinate system is a coordinate system with the horizontal direction as the X axis.

It will be appreciated, the virtual coordinates of the center of support platform 1 'means a rotating support platform, a support platform for simulating the virtual printing' (x _{_0,} y ₀₎ coordinates of the center of rotation of the supporting platform (x _{_0,} y ₀₎ the same .

The digital model of the 3D object on the virtual support platform 1'is located in the Cartesian coordinate system. The relative position of the origin of the Cartesian coordinate system and the center of the virtual support platform is not limited. The origin of the Cartesian coordinate system can be the same as the center of the virtual support platform 1'. Common points, the origin of the rectangular coordinate system can also be offset from the center of the virtual support platform 1'.

In the second embodiment, the offset of the origin of the rectangular coordinate system and the center of the virtual support platform 1'is taken as an example for description.

In the rectangular coordinate system, the data processing module 5 (slicing software) is used to slice and layer the digital model of the 3D object to be printed to obtain multiple slice layers and layer image data. The layer image data is a bitmap image, also called a dot image. There are M rows and N columns in the dot matrix image. The extending direction of the rows and the extending direction of the columns are respectively parallel to the directions of the two coordinate axes in the Cartesian coordinate system. Each pixel is expressed as d _mn , and m is the row of the pixel. , N represents the column where the pixel is located, 1≤m≤M, 1≤n≤N, d _mn represents the pixel on the mth row and nth column. The specific dot matrix image composition is determined by the specific 3D object to be printed. The structure and shape are determined.

Wherein, the layer image data includes a plurality of pixels to be printed, and the pixels to be printed include at least one of pixels that need inkjet printing and pixels that do not need inkjet printing.

Refer to FIG. 7, which is a schematic diagram of the relative position of the layer image data of all slices on the virtual support platform 1'in the rectangular coordinate system in Embodiment 2 of the present application.

The slice layer image 6'is located on the virtual support platform 1', the center O of the virtual support platform 1'(ie, the rotating support platform 1) has coordinates (x ₀ , y ₀ ) in the rectangular coordinate system XY, and the slice layer image 6' It is a dot matrix image, where M=6 rows and N=9 columns; the extending direction of the rows is parallel to the X axis, and the extending direction of the columns is parallel to the Y axis.

The slice layer image 6'includes pixels that do not require inkjet printing, represented by hollow dots K, and pixels that need inkjet printing, represented by solid dots S.

Each pixel in the slice layer image 6'has a relative positional relationship. For example, taking the pixel d ₁₁ in the first row and the first column as a reference, the pixel in the first row and the second column is represented as d ₁₂ ,... By analogy, the pixel in the first row and the ninth column is denoted as d ₁₉ ; the pixel in the second row and the first column is denoted as d ₂₁ , and the pixel in the second row and second column is denoted as d ₂₂ ,...the sixth row The pixel in the 9th column is denoted as d ₆₉ .

In the second embodiment, step S02' is included after step S11, and step S02' includes:

Obtaining the coordinates of a plurality of pixels to be printed in the layer image data according to the coordinates of at least one pixel to be printed in the layer image data in a rectangular coordinate system;

The limit radial distance between the slice layer and the center of the rotating support platform is determined according to the coordinates of a plurality of pixels to be printed and the coordinates of the center of the rotating support platform.

_{Understandably, after the coordinates (x mn} , y _mn ) of at least one pixel to be printed in the layer image data relative to the preset rectangular coordinate system are determined, it can be determined according to each pixel in the dot matrix image of the slice layer image 6' The relative positions between the points get the coordinates of all other pixels.

Referring to FIG. 8, FIG. 8 is a schematic diagram of the uniform radial movement area of the print head in the Cartesian coordinate system in Embodiment 2 of the present application.

In the rectangular coordinate system, the coordinates of the center O of the virtual support platform 1'are (x ₀ , y ₀ ), and the coordinates of the pixel point d _mn in the slice layer image 6'are expressed as (x _mn , y _mn ). The coordinates of each pixel in the slice layer image _{6'are obtained, and the radial distance r mn of the} _{pixel d mn} from the center O of the virtual support platform 1'is obtained, and the calculation method is Formula 1:

By comparing _{the size of r mn} of all pixels, the limit radial distance between the slice layer and the center of the rotating support platform is obtained, that is, the maximum radial distance r _max and the minimum radial distance r _min .

It can be seen from Figure 8 that _{the radial distance between the pixel point d 19 and} the center O of the virtual support platform 1'is the largest, that is, r _max = r ₁₉ is the maximum radial distance; the pixel point d ₆₁ is the distance from the center O of the virtual support platform 1' The radial distance is the smallest, r _min =r ₆₁ . In this embodiment, the pixels d ₁₉ and d ₆₁ are pixels that do not require inkjet printing.

Step S03: Determine the boundary position of the uniform radial movement of the print head according to the arc formed by taking the center of the rotating support platform as the center and the limit radial distance as the radius.

_{In this embodiment, the arc R 2} ′ formed with the center O of the rotating support platform as the center and the minimum radial distance r _min as the radius is determined as the first boundary position of the uniform radial movement of the print head; _{The arc R 3} ′ formed by the center O being the center of the circle and the maximum radial distance r _max being the radius is determined as the second boundary position of the uniform radial movement of the print head.

As shown in FIG. 8, _{the annular area 54 formed between the arc R 2} ′ and the arc R ₃ ′ is the uniform radial movement area of the print head.

Of course, the boundary position of the uniform radial movement of the print head can also be determined according to the other two boundary position determination methods in Embodiment 1, which will not be described in detail here.

Further, the layer printing data is acquired according to the layer image data 6'of the slice layer, for example, the layer image data is processed by the slice software to obtain the layer printing data of the slice layer, and the layer printing data includes controlling whether at least one channel of the print head performs inkjet The data.

In this embodiment 2, step S04' is included after step S03, and step S04' includes:

_{Acquiring the first relative coordinates (x mn-} x ₀ , y _mn -y ₀ ) of at least one pixel to be printed relative to the center of the rotating support platform;

Obtain the layer printing data of the slice layer;

According to the first relative coordinates (x _mn- x ₀ , y _mn -y ₀ ), the boundary position and the layer printing data, the print head is controlled to execute the printing action, and the layer printing result is obtained.

As shown in Fig. 8, according to the limit radial distance r _max and r _min , the starting position and ending position of the uniform radial movement of the print head during the printing process are determined; according to the pixel point (for example, d ₁₁ ), the relative rotation of the center O of the support platform A relative coordinate is (x ₁₁ -x ₀ , y ₁₁ -y ₀ ), so as to determine the specific position of the layer image data on the virtual support platform, and finally determine the specific position of the print head to perform printing on the rotating support platform; and then according to the slice The layer printing data of the layer is inkjet printed in the radial uniform motion area enclosed by the boundary position and the specific inkjet printing position determined, so as to print the slice layer of the 3D object.

In Embodiment 2, the radial uniform movement area 54 of the print head 2 is smaller than the annular area of the rotating support platform 1. Therefore, the uniform movement area of the print head in the radial invalid printing is reduced, and the printing efficiency of a single slice layer is improved. In turn, the molding efficiency of 3D objects is improved, and the operating cost of the printer is reduced.

Similarly, in Embodiment 2, during the printing process of the print head, the rotation speed value of the rotating support platform can also be set, for example, set to a preset value; or set to be the same as the maximum value of the currently printed slice layer. The radial distance changes in an inverse proportional relationship; and/or, it is set to change in a direct proportional relationship with the uniform radial velocity of the print head. I will not go into details here.

The specific technical solution of the method for printing a slice layer of a 3D object provided in the third embodiment will be described in detail below.

FIG. 9 is a schematic flowchart of a method for rotating and printing a slice layer of a 3D object provided in Embodiment 3 of the present application. FIG. 10 is a schematic diagram of the uniform radial movement area of the print head in the Cartesian coordinate system in Embodiment 3 of the present application.

Referring to Figures 9-10, on the basis of the foregoing embodiment 2, step S02" includes:

The limit radial distance between the slice layer and the rotating support platform is determined according to the coordinates of the pixels to be inkjet printed among the plurality of pixels to be printed and the coordinates of the center of the rotating support platform.

Specifically, each pixel in the layer image data 6'is traversed, the pixel that needs inkjet printing is identified, and the radial distance r of all the pixels that need inkjet printing from the center O of the virtual support platform 1'is obtained. _mn .

_{By comparing the size of r mn} of all the pixels that need inkjet printing, the limit radial distance between the slice layer and the center of the rotating support platform is obtained, that is, the maximum radial distance r _max and the minimum radial distance r _min .

Understandably, the pixels that need inkjet printing in this embodiment have attribute data such as color data, material performance data, etc., while the pixels that do not need inkjet printing have no attribute data. Therefore, when traversing the pixels in the layer image data 6', it is easy to identify the pixels that need inkjet printing.

It can be seen from Figure 9 that _{the radial distance between the pixel point d 39 and} the center O of the virtual support platform 1'is the largest, that is, r _max = r ₃₉ is the maximum radial distance; the pixel point d ₄₂ is the distance from the center O of the virtual support platform 1' The radial distance is the smallest, r _min =r ₄₂ . In this embodiment, the pixels d ₃₉ and d ₄₂ are both pixels that need inkjet printing.

_{In this embodiment, the arc R 2} "formed with the center O of the rotating support platform as the center and the minimum radial distance r _min as the radius is determined as the first boundary position of the uniform radial movement of the print head; _{The arc R 3} "formed by the center O being the center of the circle and the maximum radial distance r _max being the radius is determined as the second boundary position of the uniform radial movement of the print head.

As shown in FIG. 9, _{the annular area 55 formed between the arc R 2} ”and the arc R ₃ ” is the uniform radial movement area of the print head.

In the third embodiment, step S04" is executed after step S03, and step S04" includes:

Obtain the smallest circumscribed rectangle of the pixel that needs inkjet printing among the multiple pixels to be printed in the layer image data;

_{Obtain the coordinates (x mn} ', y _mn ') of at least one pixel to be printed within the minimum circumscribed rectangle and the second relative coordinates of at least one pixel to be printed relative to the center of the rotating support platform (x _mn'- x ₀ , Y _mn' -y ₀ );

Extract the layer image data data within the smallest circumscribed rectangle as layer printing data;

According to the second relative coordinates (x _mn'- x ₀ , y _mn' -y ₀ ), the boundary position and the layer printing data, the print head is controlled to execute the printing action, and the layer printing result is obtained.

Specifically, each pixel in the slice layer image 6'is traversed, and after the pixel that needs inkjet printing is identified, the coordinates of the pixel that needs inkjet printing are filtered out of x _min , y _min , and x _max And y _max , which can determine the smallest circumscribed rectangle 7 of all pixels that need inkjet printing.

Continuing to refer to Figure 10, the directions of the long and wide sides of the smallest circumscribed rectangle are parallel to the X and Y axes of the Cartesian coordinate system, and the vertices of the smallest circumscribed rectangle 7 are pixel points d ₂₂ , d ₂₉ , and d _{52 respectively.} , D ₅₉ , the coordinates are (x _min , y _max ), (x _max , y _max ), (x _min , y _min ), (x _max , y _min ), respectively.

In the third embodiment, the at least one pixel to be printed within the range of the smallest circumscribed rectangle 7 specifically refers to at least one vertex of the smallest circumscribed rectangle (such as vertices d ₂₂ , d ₂₉ , d ₅₂ or d ₅₉ ); the second relative coordinate of the at least one pixel to be printed with respect to the center of the rotating support platform specifically refers to the second relative coordinate of at least one vertex of the smallest circumscribed rectangle with respect to the center of the rotating support platform, For _{_{example, (x 22 '-x 0,}} y 22' -y 0). As another optional solution of this embodiment 3, at least one pixel to be printed within the minimum circumscribed rectangle 7 may be any point other than the vertex, such as d ₂₃ , or d ₃₄ , or d ₂₆ and so on, no more detailed introduction here.

According to the second relative coordinates, the specific position of the layer image data on the virtual support platform is determined, and the specific position of the print head to perform printing on the rotating support platform is finally determined; and then the layer print data of the slice layer is surrounded by the boundary position. Inkjet printing is performed in the combined radial uniform motion area and the determined specific inkjet printing position, thereby printing the slice layer of the 3D object.

In Embodiment 3, the radial uniform movement area 55 of the print head 2 is smaller than the annular area of the rotating support platform 1. Therefore, the uniform movement area of the print head in the radial invalid printing is reduced, and the printing efficiency of a single slice layer is improved. In turn, the molding efficiency of 3D objects is improved, and the operating cost of the printer is reduced.

In Embodiment 3, the data of the layer image data 6" within the smallest circumscribed rectangle is extracted as the layer printing data. Compared with the layer image data 6', the new layer image data 6" further reduces the number of pixels that do not need inkjet printing. , Which reduces the amount of data storage, improves the efficiency of data transmission, and at the same time reduces the range of invalid movement of the print head in the uniform movement area in the radial direction, thereby improving the printing efficiency of the slice layer.

Similarly, in Embodiment 3, during the printing process of the print head, the rotation speed value of the rotating support platform can also be set, for example, set to a preset value; or set to be the same as the maximum value of the currently printed slice layer. The radial distance changes in an inverse proportional relationship; and/or, it is set to change in a direct proportional relationship with the uniform radial velocity of the print head. I will not go into details here.

Example 4

Refer to FIG. 11, which is a schematic diagram of a method for printing a 3D object according to Embodiment 4 of the present application. As shown in Figure 11, the 3D object printing method includes:

Step S201, controlling the rotation speed of the rotating support platform 1 to be a first preset value, and printing by using the 3D object slice layer printing method of any one of the embodiments 1 to 3 to obtain the layer printing result of the first slice layer;

Step S202, controlling the rotation speed of the rotating support platform to a second preset value, and printing according to the layer printing data of the Nth slice layer, where N is a positive integer greater than 1, and the layer printing results obtained by printing are sequentially Layers are superimposed to obtain a 3D object; the second preset value is greater than or equal to the first preset value.

Specifically, the second preset value is equal to the first preset value. The printing process of step S202 and the printing process of step S201 have the same radial uniform motion area of the print head. Specifically, after the first slice layer is printed using the 3D object slice layer printing method in Embodiment 1, only the layer printing data of the subsequent slice layer needs to be acquired during the printing process of the subsequent slice layer, and the layer printing data of the subsequent slice layer is acquired according to the acquired subsequent slice layer. The layer printing data and the limit radial distance between the stored slice layer and the center of the rotating support platform (that is, the minimum radial distance and the maximum radial distance) are printed for the subsequent slice layers and superimposed layer by layer to form a 3D object.

After the first slice layer is printed using the 3D object slice layer printing method in embodiment 2 and embodiment 3, only the layer printing data of the subsequent slice layer needs to be obtained during the printing process of the subsequent slice layer, and the subsequent slice layer is obtained according to the obtained subsequent slice layer. The layer printing data of the layer, the limit radial distance between the stored slice layer and the center of the rotating support platform (that is, the minimum radial distance and the maximum radial distance), and the relative coordinates of at least one pixel to be printed from the center of the rotating support platform ( _{_{(x mn '-x 0, y}} mn' -y 0) as described in Example _{_{_{(x mn -x 0, y mn}}} -y 0) 2, in Example 3) prints the subsequent slice layer, and by Layers are superimposed to form a 3D object.

Optionally, the second preset value is greater than the first preset value. According to any one of the above-mentioned embodiments 1 to 3, the rotation speed value of the rotating support platform changes in inverse proportion to the maximum radial distance of the currently printed slice layer. Under the premise of ensuring the mechanical performance of the printer and meeting the printing accuracy, in the subsequent During the printing process of the slice layer, according to the reduction of the maximum radial distance between the current slice layer and the center of the rotating support platform, the rotation speed value of the rotating support platform during the current slice layer printing process can be increased, and the diameter of the print head can be increased at the same time. The speed of moving toward a uniform speed; after the rotation speed of the rotating support platform and the speed of the radial uniform movement of the print head are determined, follow the method of printing the first slice layer in this embodiment 4, print the subsequent slice layers, and Overlay layer by layer to form a 3D object.

In this embodiment, since the printing of the slice layer reduces the uniform motion area of the print head for ineffective printing in the radial direction, the printing efficiency of a single slice layer is improved, thereby improving the molding efficiency of 3D objects and reducing the operating cost of the printer.

Example 5

Referring to FIG. 12, FIG. 12 is a schematic diagram of a method for printing a 3D object according to Embodiment 5 of the present application, and the details are as follows:

In step S301, each slice layer is printed using the 3D object slice layer printing method of any one of embodiments 1 to 3. During the printing process, the rotation speed value of the rotating support platform is set to be proportional to the uniform radial movement speed of the print head Relationship change

In step S302, the layer printing results obtained by printing are superimposed layer by layer to obtain a 3D object.

Specifically, taking the value of the rotation speed of the rotating support platform when printing the first slice layer as ω ₁ , the speed of uniform movement in the radial direction as V _j1 , and the maximum radial distance of the first slice layer as r _max1 , when the first slice layer is printed when a slice layer q, q maximum radial distance of the slice layer is _{_{_{r maxq, r maxq <r max1}}} , then this time may be adjusted rotational speed is ω ₂ support platform when printing q-th slice layer, Make ω ₂ ＞ω ₁ , and adjust the current radial uniform motion speed of the print head to V _jq according to the size of ω2, so that V _jq ＞V _j1 ; when printing the q+1 slice layer, q+1 rotation of the rotary platform supporting the maximum radial distance of the slice layer is _{r max (q + 1),} r max (q + 1) <r maxq <r max1, then this time may be adjusted first print slice layer q + 1 The speed value is ω _q+1 , make ω _q+1 ＞ω ₂ ＞ω ₁ , and adjust the current uniform radial movement speed of the print head to V _jq+1 _{according to the size of ω q} +1, so that V _jq+1 ＞ V _jq > V _j1 .

The adjustment of the rotation speed value of the rotating support platform and the speed of the uniform radial movement of the print head in each embodiment of the present application is performed under the premise of meeting the mechanical performance of the printer and the printing accuracy of the 3D object.

Example 6

1, Embodiment 6 of the present application provides a 3D object printing device, including a rotating support platform 1, a printing head 2, a carriage, a sliding rail 3, a control component 4, and a data processing module 5, wherein the printing head 2 is installed On the word car.

The data processing module 5 is used to slice and layer the object to be printed to obtain multiple slice layers and layer image data, and process the layer image data, and the data processing module is connected with the control component;

The print head is used for jetting printing materials, and the print head is connected with the control part;

The rotating support platform is used to support the layer printing result of the object to be printed; and

The control component is used for using the 3D object slice layer printing method of any one of Embodiments 1 to 3 to control the rotating support platform and the printing head to perform printing operations.

The above are only preferred embodiments of this application, and are not intended to limit this application. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of this application shall be included in the protection of this application. Within range.

Claims

A method for printing a slice layer of a 3D object, characterized in that the method comprises:

Acquiring the layer image data of the slice layer of the object to be printed;

Determining the limit radial distance between the slice layer and the center of the rotating support platform according to the layer image data, wherein the limit radial distance includes a minimum radial distance and/or a maximum radial distance;

Determine the boundary position of the uniform radial movement of the print head according to an arc formed by taking the center of the rotating support platform as the center and the limit radial distance as the radius;

Obtain the layer printing data of the slice layer, and control the print head to perform a printing action according to the boundary position and the layer printing data to obtain a layer printing result.
The method according to claim 1, wherein the determining the limit radial distance between the slice layer and the center of the rotating support platform according to the layer image data comprises:

Position the multiple pixels to be printed in the layer image data through a preset polar coordinate system to obtain the coordinates (r i , θ i ) of the multiple pixels to be printed, where r i represents the ith The distance between a pixel to be printed and the pole, θ i represents the polar angle of the i-th pixel to be printed;

The limit radial distance between the slice layer and the center of the rotating support platform is determined according to the coordinates (r i , θ i ) of the plurality of pixels to be printed.
The method according to claim 2, wherein the polar coordinate system is a polar coordinate system with the center of the rotating support platform as the pole.
The method according to claim 1, characterized in that, before the determining the limit radial distance between the slice layer and the center of the rotating support platform according to the layer image data, the method further comprises:

Obtain the coordinates (x 0 , y 0 ) of the center of the rotating support platform in the preset rectangular coordinate system;

Acquire the coordinates (x mn , y mn ) of at least one pixel to be printed in the layer image data in the preset rectangular coordinate system; wherein, the rectangular coordinate system is a coordinate system whose horizontal direction is the X axis .
The method according to claim 4, wherein the determining the limit radial distance between the slice layer and the center of the rotating support platform according to the layer image data comprises:

Obtaining the coordinates of a plurality of pixels to be printed in the layer image data according to the coordinates of the at least one pixel to be printed in the layer image data in the rectangular coordinate system;

The limit radial distance between the slice layer and the center of the rotating support platform is determined according to the coordinates of the plurality of pixels to be printed and the coordinates of the center of the rotating support platform.
5. The method according to claim 5, wherein the acquiring the layer printing data of the slice layer, controlling the print head to perform a printing action according to the boundary position and the layer printing data, to obtain a layer printing result, include:

Acquiring the first relative coordinates (x mn- x 0 , y mn -y 0 ) of the at least one pixel to be printed relative to the center of the rotating support platform;

Acquiring layer printing data of the slice layer;

According to the first relative coordinates, the boundary position, and the layer printing data, the print head is controlled to perform a printing action to obtain a layer printing result.
The method according to claim 2 or 5, wherein the pixel to be printed includes at least one of a pixel that needs inkjet printing and a pixel that does not need inkjet printing.
The method according to claim 4, wherein the determining the limit radial distance between the slice layer and the center of the rotating support platform according to the layer image data comprises:

Obtaining the coordinates of a plurality of pixels to be printed in the layer image data according to the coordinates of the at least one pixel to be printed in the layer image data in the rectangular coordinate system;

The limit radial distance between the slice layer and the center of the rotating support platform is determined according to the coordinates of the pixel points that need inkjet printing among the plurality of pixels to be printed and the coordinates of the center of the rotating support platform.
8. The method according to claim 8, wherein the acquiring the layer printing data of the slice layer, controlling the print head to perform a printing action according to the boundary position and the layer printing data, to obtain a layer printing result, include:

Obtaining the smallest circumscribed rectangle of the pixel that needs inkjet printing among the plurality of pixels to be printed in the layer image data;

Obtain the coordinates (x mn ′, y mn ′) of at least one pixel to be printed within the minimum circumscribed rectangle and the second relative coordinate (x mn ′, y mn ′) of the at least one pixel to be printed relative to the center of the rotating support platform ( x mn'- x 0 , y mn' -y 0 );

Extracting data of the layer image data within the minimum circumscribed rectangle range as layer printing data;

According to the second relative coordinates, the boundary position, and the layer printing data, the print head is controlled to perform a printing action to obtain a layer printing result.
The method according to claim 9, wherein at least one pixel to be printed in the range of the smallest circumscribed rectangle is at least one vertex of the smallest circumscribed rectangle; and the at least one pixel to be printed is opposite to all the pixels to be printed. The second relative coordinate of the center of the rotating support platform is the second relative coordinate of the at least one vertex relative to the center of the rotating support platform.
The method according to claim 2 or 5 or 8, wherein the limit radial distance includes a minimum radial distance, and the basis is that the center of the rotating support platform is a circle center and the limit radial distance is The arc formed by the radius is determined as the boundary position of the uniform radial movement of the print head, including:

Determining an arc formed by taking the center of the rotating support platform as the center and the minimum radial distance as the radius as the first boundary position of the uniform radial movement of the print head;

The outer circumference of the rotating support platform is determined as the second boundary position of the uniform radial movement of the print head.
The method according to claim 2 or 5 or 8, wherein the limit radial distance comprises a maximum radial distance, and the basis is that the center of the rotating support platform is a circle center and the limit radial distance is The arc formed by the radius is determined as the boundary position of the uniform radial movement of the print head, including:

Determining the inner circumference of the rotating support platform as the first boundary position of the print head moving at a uniform speed in the radial direction;

A circular arc formed with the center of the rotating support platform as the center and the maximum radial distance as the radius is determined as the second boundary position of the uniform radial movement of the print head.
The method according to claim 2 or 5 or 8, wherein the limit radial distance includes a minimum radial distance and a maximum radial distance; the basis is centered on the center of the rotating support platform and the The radial distance is the arc formed by the radius, which is determined as the boundary position of the uniform radial movement of the print head, including:

Determining an arc formed by taking the center of the rotating support platform as the center and the minimum radial distance as the radius as the first boundary position of the uniform radial movement of the print head;

A circular arc formed with the center of the rotating support platform as the center and the maximum radial distance as the radius is determined as the second boundary position of the uniform radial movement of the print head.
The method according to claim 1, characterized in that, before said acquiring the layer image data of the slice layer of the object to be printed, the method further comprises:

Slice and layer the digital model of the object to be printed to obtain multiple slice layers and layer image data of the multiple slice layers.
2. The method according to claim 1, wherein the layer printing data of the slice layer is acquired, and the print head is controlled to perform a printing action according to the boundary position and the layer printing data to obtain a layer printing result ,include:

During the printing process, set the rotation speed of the rotating support platform to a preset value; or

Set the rotation speed value of the rotating support platform to change in an inverse proportional relationship with the maximum radial distance of the slice layer currently printed; and/or

The rotation speed value of the rotating support platform is set to change in a proportional relationship with the speed of the uniform radial movement of the print head.
The method according to claim 1, wherein the object to be printed includes a physical structure part, or a physical structure part and a non-physical structure part.
The method according to claim 16, wherein the non-physical structure part comprises at least one of a supporting structure part and an extended structure part.
A method for printing a 3D object, characterized in that the method includes:

Control the rotation speed of the rotating support platform to be the first preset value, and use the 3D object slice layer printing method of any one of claims 1 to 17 to print to obtain the layer printing result of the first slice layer; Then, the rotation speed of the rotating support platform is controlled to be the second preset value, and printing is performed according to the layer printing data of the Nth slice layer, where N is a positive integer greater than 1, and the layer printing results obtained by printing are successively printed. Layers are superimposed to obtain a 3D object; the second preset value is greater than or equal to the first preset value.
A printing device for 3D objects, characterized in that it comprises:

A data processing module, configured to slice and layer the object to be printed to obtain multiple slice layers and layer image data, and process the layer image data, and the data processing module is connected to the control component;

A print head for jetting printing materials, the print head is connected with the control component;

A rotating support platform for supporting the layer printing result of the object to be printed; and

The control component is configured to use the method for printing a slice layer of a 3D object according to any one of claims 1 to 17 to control the rotating support platform and the print head to perform a printing action.