WO2021097744A1

WO2021097744A1 - Dynamic measuring apparatus for three-dimensional size and measurement method therefor

Info

Publication number: WO2021097744A1
Application number: PCT/CN2019/119877
Authority: WO
Inventors: 张�浩; 曹亮; 张晓非; 周之琪; 丁宵月; 郑清志
Original assignee: 北京机电研究所有限公司; 北京清影机器视觉技术有限公司
Priority date: 2019-11-21
Filing date: 2019-11-21
Publication date: 2021-05-27
Also published as: CN112639390A

Abstract

A dynamic measuring apparatus for a three-dimensional size, comprising a plane camera group (100) used to dynamically measure the three-dimensional size of a free-forged forge piece, wherein the plane camera group (100) comprises at least four image sensors (101) and a three-dimensional operational circuit board (102), the three-dimensional operational circuit board (102) is separately electrically connected to a plurality of image sensors (101), and the three-dimensional operational circuit board (102) is configured to calculate a plurality of image data into three-dimensional size data. By means of using non-contact optical imaging, the three-dimensional outer contour size of the forge piece is dynamically measured at high speeds, so that the size of the forge piece may be measured during the forging process, and then forging process parameters of each step may be determined. The forging position and pressing depth of the forge piece may be adjusted to to reduce the labor intensity of workers, so that each step of the process may have a process size record. By means of obtaining the three-dimensional size data result, the processing quality of the forge piece may be greatly improved, and the uniformity of the processing size of the forge piece is improved. Further relating to a measurement method for a three-dimensional size.

Description

Dynamic measuring device and measuring method for three-dimensional size

Technical field

This application relates to the technical field of three-dimensional size detection, in particular, to a dynamic measuring device and a measuring method for three-dimensional size.

Background technique

Free forging is a metal forming process that uses forging equipment such as large hydraulic presses or hydraulic presses to form high-temperature forging blanks into qualified forgings through multiple pressings. Most of the forgings processed by free forging are large forgings. Since the temperature of the forgings is generally 1200℃～500℃, and the weight of the forgings is heavy and bulky, in the process of free forging, mechanical clamping equipment is used to control the feed of the forgings. Rotating and raising and lowering, the forging equipment and clamping machine are operated by the staff in the room to complete the forging process.

At the forging site, the forging process commander and the operator are required to cooperate to complete the forging process. The commander directs the operator to operate through gestures. The forging depth and the adjustment of the pressing position of the forging all rely on human observation, gesture command and manual operation of the operator. . In the prior art, in order to solve the disadvantages of free forging that rely on manual operation and human eyes to observe the size, various types of laser measuring equipment are used to measure the size of free forging.

However, in the prior art, red hot forgings produce high-temperature radiation, which seriously interferes with laser reflection, making it difficult to meet the accuracy requirements of the measurement; further, because the laser measurement generally adopts a single-point measurement method, when the overall forging measurement surface is large, The laser scanning time is too long to achieve real-time measurement. At the same time, due to the large curvature of the shaft forgings, the use of lasers and other methods that rely on reflection measurement makes it difficult to generate reflected signals at the edge of the horizontal axis and cannot be measured. Therefore, there are still many defects in the current technology for the three-dimensional size measurement of free forging.

Application content

The present application provides a dynamic measuring device for three-dimensional dimensions and a measuring method thereof, which can at least realize the technical effect of dynamic measuring the three-dimensional dimensions of free forgings.

The embodiments of this application can be implemented as follows:

The embodiment of the present application provides a dynamic measurement device for three-dimensional size, including: a plane camera group;

The planar camera group includes at least four image sensors and a three-dimensional arithmetic circuit board, a plurality of the image sensors are located in the same plane, and the plurality of the image sensors are in a rectangular structure, and the optical axes of the plurality of the image sensors are parallel Configured to align the scan lines of the plurality of image sensors in both horizontal and vertical directions;

The three-dimensional arithmetic circuit board is electrically connected to a plurality of the image sensors, and the three-dimensional arithmetic circuit board is configured to calculate a plurality of image data into three-dimensional size data.

Optionally, it also includes a lens;

The number of the lenses is the same as the number of the image sensors, and the lenses are connected to the image sensor in a one-to-one correspondence.

Optionally, it also includes a far-infrared filter;

The end of the lens away from the image sensor is connected to the far-infrared filter.

Optionally, it also includes a camera mount and a camera shock absorber;

The bottom of the flat camera group is connected with the camera mounting base, and the side of the camera mounting base away from the flat camera group is connected with the camera shock absorber.

Optionally, there are a plurality of the camera shock absorbers, and the plurality of camera shock absorbers are uniformly arranged along the camera mount.

Optionally, it also includes a heat-insulating casing;

The flat camera group, the camera mounting base and the camera shock absorber are all arranged in the thermal insulation casing, and the end of the camera shock absorber away from the camera mounting base is connected to the inner wall of the thermal insulation casing;

A side of the heat-preserving casing corresponding to the image sensor is provided with first through holes, and the number of the first through holes is the same as the number of the image sensors.

Optionally, each of the first through holes is provided with high temperature resistant tempered glass.

Optionally, it also includes a heat dissipation mechanism;

The heat-preserving casing is provided with a second through hole on a side away from the first through hole, the heat dissipation mechanism is disposed at the second through hole, and the heat-dissipating mechanism is connected to the side of the heat-preserving casing The walls are connected and configured to reduce the temperature in the thermal insulation casing.

Optionally, the exterior of the heat-preserving casing is covered with a heat-insulating layer.

Optionally, it also includes a bracket;

The outside of one side wall of the heat-preserving casing is connected with the bracket, and the inside of the side wall of the heat-preserving casing is connected with the camera shock absorber.

Optionally, the support includes a column and a bracket;

The bracket is slidably connected with the upright column, and the heat-preserving casing is connected with the bracket.

Optionally, it also includes a chassis shock absorber;

The chassis shock absorber is arranged between the heat-preserving chassis and the bracket, and the chassis shock absorber is connected to the heat-preserving chassis and the bracket respectively.

Optionally, there are a plurality of chassis shock absorbers, and the plurality of chassis shock absorbers are uniformly arranged along the bracket.

Optionally, it also includes a display terminal;

The display terminal is electrically signal connected with the three-dimensional computing circuit board.

Optionally, the three-dimensional arithmetic circuit board adopts an FPGA (Field Programmable Gate Array) three-dimensional arithmetic circuit board.

An embodiment of the present application provides a measurement method based on the dynamic measurement device for three-dimensional dimensions, including the following steps:

Perform pairwise convolution matching operations on multiple two-dimensional images to obtain the three-dimensional coordinate positions of the edges of the object and the image feature points.

Optionally, during the image acquisition process, the automatic exposure parameter adjustment is performed according to the change of the image brightness caused by the change of the object temperature, and the configuration is configured so that the sharpness of the image remains unchanged.

Optionally, it also includes the following steps:

Establish a spatial rectangular coordinate system of multiple image sensors;

The origin of the spatial rectangular coordinate system of the plurality of image sensors is set on the plane corresponding to the focal point of the optical axis of the plurality of image sensors, and is located at the center point of the rectangular structure composed of the plurality of image sensors;

So that there is a unique correspondence between a group of pixels in multiple image sensors and a point on any object in space;

According to the spatial geometric constraints on multiple image sensors and the image similarity matching function, the spatial position coordinates of a point on any object in the space are obtained.

Optionally, the step of forming a unique correspondence between a group of pixels in the multiple image sensors and the points further includes:

Obtain the corresponding points in the horizontal direction of multiple image sensors corresponding to a point on any object in space, the corresponding points in the horizontal direction are located on the same horizontal scan line, and the corresponding points in the vertical direction are located on the same vertical scan line Above, the corresponding points at the diagonal positions are located on the same diagonal line, and multiple pixels simultaneously form a rectangle similar to the rectangle formed by multiple image sensors, so that the formed rectangle forms a matching spatial geometric constraint condition.

Optionally, it further includes the following steps: using a three-dimensional computing circuit board and adopting three-dimensional image processing software, after the three-dimensional computing software obtains the spatial three-dimensional position coordinates of the pixel points, automatically calculating the dimensions of various forgings that need to be measured;

Among them, the 3D image processing software is based on general image processing algorithms and automatic object recognition methods based on neural networks, extracts the three-dimensional size of the forging edge, automatically tracks the forging, separates the background and automatically extracts the size of the forging.

The beneficial effects of the present application include, for example, the use of a plane camera group for dynamic measurement of three-dimensional dimensions of free forging forgings. The plane camera group includes at least four image sensors and a three-dimensional computing circuit board, multiple image sensors are located in the same plane, and multiple images The sensor has a rectangular structure, the optical axes of the multiple image sensors are arranged in parallel, and the scanning lines of the multiple image sensors are aligned horizontally and vertically; the three-dimensional computing circuit board is electrically connected to the multiple image sensors, and the three-dimensional computing circuit The plate is configured to calculate multiple image data into three-dimensional size data; through the use of non-contact optical imaging, the three-dimensional outer contour size of the forging can be dynamically measured at high speed, so that the size of the forging can be measured during the forging process, and the size of each step can be determined Forging process parameters, adjust the forging position and pressing depth of forgings, reduce the labor intensity of workers, so that each process can have process size records, by obtaining three-dimensional size data results, it can greatly improve the processing quality of forgings and increase the processing size of forgings Consistency.

Description of the drawings

In order to more clearly describe the technical solutions of the embodiments of the present application, the following will briefly introduce the drawings that need to be used in the embodiments. It should be understood that the following drawings only show certain embodiments of the present application, and therefore do not It should be regarded as a limitation of the scope. For those of ordinary skill in the art, other related drawings can be obtained based on these drawings without creative work.

FIG. 1 is a schematic diagram of the overall structure of a dynamic measurement device for three-dimensional dimensions provided by an embodiment of the application;

2 is a schematic diagram of an exploded structure of a dynamic measuring device for three-dimensional dimensions provided by an embodiment of the application;

Fig. 3 is a schematic structural diagram of a bracket for a three-dimensional dynamic measurement device provided by an embodiment of the application;

4 is a schematic structural diagram of the installation position of the dynamic measurement device for three-dimensional dimensions provided by the embodiment of the application;

FIG. 5 is a schematic structural diagram of the measurement process of the dynamic measurement device for three-dimensional dimensions provided by an embodiment of the application;

Fig. 6 is a schematic diagram of a rectangular coordinate system for a dynamic measurement method of three-dimensional dimensions provided by an embodiment of the application;

FIG. 7 is an imaging principle diagram of a dynamic measurement method for three-dimensional dimensions provided by an embodiment of the application.

Icon: 100-plane camera group; 101-image sensor; 102-three-dimensional computing circuit board; 200-lens; 300-far-infrared filter; 400-camera mount; 500-camera shock absorber; 600-heat insulation case 601-first through hole; 700-heat dissipation mechanism; 800-bracket; 801-post; 802-bracket; 900-chassis shock absorber.

Detailed ways

In order to make the purpose, technical solutions and advantages of the embodiments of the present application clearer, the technical solutions in the embodiments of the present application will be described clearly and completely in conjunction with the accompanying drawings in the embodiments of the present application. Obviously, the described embodiments It is a part of the embodiments of the present application, but not all of the embodiments. The components of the embodiments of the present application generally described and shown in the drawings herein may be arranged and designed in various different configurations.

Therefore, the following detailed description of the embodiments of the application provided in the accompanying drawings is not intended to limit the scope of the claimed application, but merely represents selected embodiments of the application. 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.

As shown in Figures 1 to 5, the embodiments of the present application provide a dynamic measurement device for three-dimensional dimensions, including: a planar camera group 100; the planar camera group 100 includes at least four image sensors 101 and a three-dimensional computing circuit board 102. The multiple image sensors 101 are located in the same plane, and the multiple image sensors 101 have a rectangular structure, and the optical axes of the multiple image sensors 101 are arranged in parallel, and the scanning lines of the multiple image sensors 101 are arranged in horizontal and vertical directions. All are aligned; the three-dimensional computing circuit board 102 is electrically connected to a plurality of image sensors 101, and the three-dimensional computing circuit board 102 is configured to calculate a plurality of image data into three-dimensional size data.

Optionally, a plurality of image sensors 101 are arranged on the image acquisition circuit, and the plurality of image sensors 101 are respectively electrically connected to the image acquisition circuit, wherein the number of the image sensors 101 may be four, six or eight, etc., preferably , The image sensor 101 adopts a 2×2 array, a 2×3 array, a 2×4 array, etc.

Optionally, the resolution range of the image sensor 101 is 5 to 40 million pixels, preferably 10 million pixels, and the optimal size of the rectangular structure formed by the center of the image sensor 101 is 280×60 mm. In addition, according to the requirements of measurement accuracy , The length and width dimensions can be enlarged or reduced.

Since the image sensor 101 provided in this embodiment preferably uses four image sensors 101, the following uses four image sensors 101 as examples, but the use of six or eight image sensors 101 still belongs to the implementation of this application. The scope of protection of the case.

Optionally, the core of the 3D arithmetic circuit board 102 is an FPGA (Field Programmable Gate Array) chip. The 3D arithmetic circuit board 102 collects four images of the image acquisition circuit board through a high-speed data channel, and calculates the four image data through the internal software of the FPGA. It is directly calculated as three-dimensional point cloud data, and the calculation result is directly transmitted to the following display terminal.

In addition, the three-dimensional computing circuit board 102 can also be installed at the display terminal. After the multiple image sensors 101 collect multiple image data, the multiple image data are transmitted to the display terminal through the image acquisition circuit. The three-dimensional computing circuit board 102 is installed at the display terminal. The display terminal performs three-dimensional calculations, but when the three-dimensional calculation circuit board 102 is installed at the display terminal, the calculation speed will be reduced and the calculation time of a single frame will be lengthened.

The beneficial effects of this embodiment include, for example, the use of a planar camera group 100 for dynamic measurement of three-dimensional dimensions of free forging forgings. The planar camera group 100 includes at least four image sensors 101 and a three-dimensional computing circuit board 102, and multiple image sensors 101 are located on the same plane. And the plurality of image sensors 101 have a rectangular structure, the optical axes of the plurality of image sensors 101 are arranged in parallel, and the scan lines of the plurality of image sensors 101 are aligned in both horizontal and vertical directions; the three-dimensional computing circuit board 102 and The multiple image sensors 101 are electrically connected, and the three-dimensional computing circuit board 102 is configured to calculate multiple image data into three-dimensional size data; through the use of non-contact optical imaging, the three-dimensional outer contour size of the forging can be dynamically measured at high speed, so that the forging process can be Measure the size of the forging, and then determine the forging process parameters of each step, adjust the forging position and pressing depth of the forging, reduce the labor intensity of the workers, and enable the process size record for each process. By obtaining the three-dimensional size data result, it can be extremely The processing quality of forgings is greatly improved, and the consistency of the processing dimensions of forgings is improved.

In addition, due to the guarantee of the quality of the forgings, the size reserved for the original forging design can be reduced, and the material cost of the workpiece can be greatly reduced. Because the data measurement feedback is timely, and at the same time, the time and frequency of manual measurement are reduced, which greatly saves the forging process time, reduces the number of reflows, and saves man-hours; optionally, the dynamic measurement device for three-dimensional dimensions provided in this embodiment On the basis, it can be combined with forging equipment to realize fully automated production of free forging in the future.

Optionally, the lens 200 is further included; the number of the lens 200 is the same as the number of the image sensor 101, and the lens 200 is connected to the image sensor 101 in a one-to-one correspondence.

Preferably, the lens 200 adopts an industrial lens, and the parameter selection of the lens 200 needs to be the same as the parameters of the corresponding image sensor 101. For measuring the size of the field of view, when a large measurement range is required to measure a large workpiece, the focal length of the lens 200 can be reduced. Value, increase the size of the target surface of the image sensor 101, increase the resolution of the image sensor 101, and increase the installation distance.

Optionally, it further includes a far-infrared filter 300; the end of the lens 200 away from the image sensor 101 is connected to the far-infrared filter 300.

Among them, the far-infrared filter 300 adopts a narrow-band pass method and only allows far-infrared light to pass. The best center wavelength of the narrow-band pass is 850nm. After using the far-infrared filter 300, the background interference can be effectively removed, and the The high temperature red hot forgings are clearly displayed in the image.

Optionally, it further includes a camera mount 400 and a camera shock absorber 500; the bottom of the flat camera group 100 is connected to the camera mount 400, and the side of the camera mount 400 away from the flat camera group 100 is connected to the camera shock absorber 500.

Optionally, multiple camera shock absorbers 500 are provided, and the multiple camera shock absorbers 500 are uniformly arranged along the camera mount 400.

In order to ensure the stability of the flat camera group 100 during the shooting process, a camera mount 400 is provided at the bottom of the flat camera group 100, and the camera shock absorber 500 is installed at the bottom of the camera mount 400, wherein the number of camera shock absorbers 500 Four or six uniformly distributed methods can be used; alternatively, the camera shock absorber 500 can use a special shock absorber for steel nonlinear cameras.

Optionally, it further includes a thermal insulation housing 600; the flat camera group 100, the camera mount 400, and the camera shock absorber 500 are all arranged in the thermal insulation housing 600, and the end of the camera shock absorber 500 away from the camera mount 400 is connected to the thermal insulation The inner wall of the casing 600 is connected; a side of the heat-preserving casing 600 corresponding to the image sensor 101 is provided with a first through hole 601, and the number of the first through hole 601 is the same as the number of the image sensor 101.

Optionally, the heat-preserving casing 600 is made of aluminum alloy without temperature deformation, and the heat-preserving casing 600 is provided with four first through holes 601 configured as lens interfaces at positions corresponding to the image sensor 101. Preferably, in the heat-preserving casing 600 The aluminum alloy radiator can be installed separately on the back of the device, and two external interfaces for power supply and data are designed.

Optionally, each first through hole 601 is provided with high temperature resistant tempered glass, which can be used for the image collection of the lens 200 and the flat camera group 100 to transmit light and withstand high temperature.

Optionally, it further includes a heat dissipation mechanism 700; the heat-preserving casing 600 is provided with a second through hole on the side far away from the first through hole 601, the heat-dissipating mechanism 700 is disposed at the second through hole, and the heat-dissipating mechanism 700 and the heat-preserving casing The side walls of the 600 are connected and configured to reduce the temperature in the heat-preserving cabinet 600.

Wherein, the heat-insulating casing 600 has a second through hole configured to install the heat dissipation mechanism 700 relative to the rear of the lens 200. Preferably, the heat-dissipating mechanism 700 adopts an exhaust fan; a circular hole can be opened at the bottom of the heat-insulating casing 600 to be configured as Through the transmission cable and the connection with the cable protective sleeve.

Optionally, a plurality of heat dissipation mechanisms 700 may be provided, and the plurality of heat dissipation mechanisms 700 are uniformly arranged on one side of the heat preservation casing 600, and the number of the second through holes corresponds to the number of the heat dissipation mechanisms 700 in a one-to-one manner.

In order to prevent the temperature of the heat-preserving cabinet 600 from increasing due to high-temperature radiation, optionally, the exterior of the heat-preserving cabinet 600 is covered with a heat-insulating layer, wherein the heat-insulating layer is made of asbestos heat-insulating pads, and the outer parts of the asbestos-insulating pads The bakelite board is used to fix the asbestos insulation pad, and it can also play a role in heat insulation.

Optionally, a bracket 800 is further included; the outside of one side wall of the heat-insulating casing 600 is connected to the bracket 800, and the inside of the side wall of the heat-insulating shell 600 is connected to the camera shock absorber 500.

It should be noted that since the side where the heat-insulating casing 600 is connected to the bracket 800 needs to be shaken, while the outer side wall of this side of the heat-insulating casing 600 is connected to the bracket 800, the inner side wall of the side is connected to the aforementioned camera. The vibrator 500 is connected.

In order to ensure that the plane camera group 100 can better photograph and measure the free-forged forgings, the heat-preserving housing 600 with the plane camera group 100 is connected to the bracket 800. Optionally, the distance between the bracket 800 and the center of the forging equipment is 2m-12m, preferably, the best position is 5m. At 5m, if a 16mm lens 200 and a 1-inch target surface camera are selected, the measurement range (width×height) is 3×2m.

Optionally, the bracket 800 includes an upright 801 and a bracket 802; the bracket 802 and the upright 801 are slidably connected, and the heat-preserving housing 600 is connected to the bracket 802.

Among them, the upright 801 can be fixedly connected to the ground by anchor screws, thereby ensuring the overall stability of the bracket 800. The bracket 802 and the upright 801 can slide in a variety of ways, for example, by sliding a slider and a groove, A sliding block is provided on the connecting side of the bracket 802 and the column 801, and a groove is provided on the column 801, so that the bracket 802 can slide relative to the column 801, and the bracket 802 is driven by a fixed pulley and a wire rope and a motor. Connection, through the driving function of the motor, the bracket 802 can reciprocate along the column 801, and the motor can ensure the stability of the bracket 802 through a wire rope; optionally, a damping layer is provided between the bracket 802 and the column 801 , Which can better ensure the stability of the bracket 802.

For another example: the bracket 802 and the column 801 are connected by a gear and rack in the direction of rolling, or the bracket 802 and the column 801 are connected by the meshing of multiple gears, etc., because the bracket 802 can be connected by a motor or The hoist drives the steel wire rope for driving connection, which will not be repeated here.

Optionally, it further includes a chassis shock absorber 900; the chassis shock absorber 900 is disposed between the heat-preserving chassis 600 and the bracket 802, and the chassis shock absorber 900 is connected to the heat-preserving chassis 600 and the bracket 802, respectively.

Optionally, there are multiple chassis shock absorbers 900 provided, and the multiple chassis shock absorbers 900 are uniformly arranged along the bracket 802. In order to ensure the stability of the planar camera group 100 during the shooting process, a chassis shock absorber is installed at the bottom of the heat-preserving casing 600, wherein the number of chassis shock absorbers 900 can be evenly distributed by four or six; optionally , The chassis shock absorber 900 can be a camera-specific shock absorber.

In addition, when the size of the forging exceeds the measurement area and the overall view of the forging cannot be measured, the bracket 800 can be placed farther away from the forging. At this time, the focal length of the lens 200 used is reduced, and the resolution of the image sensor 101 is increased; Alternatively, multiple brackets 800 and planar camera groups 100 are added in the parallel direction of the forging, and the three-dimensional measurement data of the multiple planar camera groups 100 are combined to form the three-dimensional data of the overall forging by using a calibration method.

Optionally, it also includes a display terminal; the display terminal is electrically connected to the three-dimensional computing circuit board 102.

Among them, the display terminal may include a PC (personal computer) machine and a display, which are connected to the three-dimensional arithmetic circuit board 102 through a cable interface and a computer terminal. Among them, the PC can be selected according to the calculation speed requirements and the reliability requirements of data storage. Ordinary PCs, industrial computers can also be used, when the data storage requirements are high, you can also use or add a set of data servers. If you need to upload data to the control and management center in real time, you can use network communication to upload the terminal data to the control and management center in real time; the display screen is installed in a location that is convenient for the operator or process commander to observe and operate, or it can be displayed in a split screen. , To display the data on two or more display screens at the same time.

In addition, it can also include external power supply equipment, image acquisition external trigger control, exhaust fan power supply, temperature sensor measurement and control circuit, forging press operating parameters automatic acquisition electrical control series of devices, in which the electrical control box and the PC through the I/O interface Receive and send control signals, and collect data from external temperature and other auxiliary sensors through the serial port.

As shown in FIGS. 6-7, the measurement method based on the dynamic measurement device for three-dimensional size provided by the embodiments of the present application includes the following steps: performing pairwise convolution matching on multiple two-dimensional images By calculation, the three-dimensional coordinate positions of the edges of the object and the image feature points are obtained.

In addition, during the image acquisition process, you can adjust the automatic exposure parameters according to the change in the image brightness caused by the temperature change of the forging, so that the sharpness of the image remains unchanged. At the same time, other image acquisition parameters also need to be automatically set and adjusted, such as : White balance, high dynamic parameters, etc.

Optionally, the method further includes the following steps: establishing the spatial rectangular coordinate system of the plurality of image sensors 101; the origin of the spatial rectangular coordinate system of the plurality of image sensors 101 is set on the plane corresponding to the focal point of the optical axis of the plurality of image sensors 101, and Located at the center point of a rectangular structure composed of multiple image sensors 101; so that there is a unique correspondence between a group of pixel points in multiple image sensors 101 and a point on any object in space; according to the information on multiple image sensors 101 The spatial geometric constraint conditions and the image similarity matching function are used to obtain the spatial position coordinates of a point on any object in the space.

Optionally, the step of forming a unique correspondence between a group of pixel points in the plurality of image sensors 101 and the point further includes: obtaining the horizontal direction of the plurality of image sensors 101 corresponding to a point on any object in space The corresponding points in the horizontal direction are located on the same horizontal scan line, while the corresponding points in the vertical direction are located on the same vertical scan line, and the corresponding points in the diagonal position are located on the same diagonal line, and there are multiple pixel points At the same time, a rectangle similar to the rectangle formed by the multiple image sensors 101 is formed, so that the formed rectangle forms a matching spatial geometric constraint condition.

The image pixel matching conditions for the above four image sensors 101 are image similarity matching functions of the image itself involving grayscale, texture, color, and the relationship with surrounding pixels.

Optionally, the image similarity matching function includes: for the spatial position coordinates of a point P(X, Y, Z) on any object in space, the calculation formula is as follows:

PN (PNx, PNy, PNz), where

Among them, m and n are the lengths of two adjacent sides of the matrix formed by the optical centers of the planar camera group 100, f is the focal length of the lens 200, and a, b, c, and d respectively represent the location when there are four image sensors 101. Plane.

In this embodiment, when the planar camera group 100 is used to perform spatial three-dimensional operations, FPGA (Field Programmable Gate Array) chips can be used to implement three-dimensional operations; when the three-dimensional arithmetic circuit board 102 is used, the original 64 The bit-serial operation becomes the parallel operation of the FPGA bus bandwidth, which can increase the operation speed and improve the reliability of the system; optionally, the 3D operation software can complete the operation on the PC terminal or the 3D operation circuit board 102 The FPGA chip is used to perform calculations, and an alternative method is to add an FPGA chip to the PC terminal to complete the three-dimensional calculation.

When the three-dimensional computing circuit board 102 adopts three-dimensional image processing software, after the three-dimensional computing software obtains the spatial three-dimensional position coordinates of the pixels, it automatically calculates the dimensions of various forgings that need to be measured. Such algorithms involve general images. Processing algorithm and automatic object recognition based on neural network, three-dimensional dimension extraction of forging edge, automatic tracking of forging, background separation, automatic extraction of key dimensions of forging, key dimensions and geometric characteristics of forging include: centerline, axis of symmetry, maximum or minimum outer diameter, Verticality, offset, curvature, etc.

Optionally, when the collection and calculation are completed, the data management software can be configured to classify and save the collected images, three-dimensional data, and measurement data, statistical calculations, and data uploads. Data recording of important process parameters and work processes is carried out to form a product process data file to facilitate the analysis of product quality and quality afterwards.

The dynamic measurement method for three-dimensional dimensions provided by the embodiments of this application uses non-contact optical imaging to dynamically measure the three-dimensional outer contour dimensions of forgings at high speed, so that the dimensions of forgings can be measured during the forging process, and each step can be determined. Forging process parameters, adjust the forging position and pressing depth of the forging, reduce the labor intensity of workers, so that each step of the process can have process size records, by obtaining three-dimensional dimensional data results, it can greatly improve the processing quality of forgings and improve the processing of forgings. Consistency of size.

The foregoing descriptions are only preferred embodiments of the application, and are not configured to limit the application. For those skilled in the art, the application may have various modifications and changes. Any modification, equivalent replacement, improvement, etc. made within the spirit and principles of this application shall be included in the scope of protection of this application.

Industrial applicability

The three-dimensional size dynamic measurement device and the measurement method provided by the embodiments of the present application are used for three-dimensional dynamic measurement of free forging forgings through a plane camera group, which can improve the processing quality of the forgings and improve the consistency of the processing sizes of the forgings.

Claims

A dynamic measuring device for three-dimensional dimensions, characterized in that it comprises: a plane camera group;

The planar camera group includes at least four image sensors and a three-dimensional arithmetic circuit board, a plurality of the image sensors are located in the same plane, and the plurality of the image sensors are in a rectangular structure, and the optical axes of the plurality of the image sensors are parallel Configured to align the scan lines of the plurality of image sensors in both horizontal and vertical directions;

The three-dimensional arithmetic circuit board is electrically connected to a plurality of the image sensors, and the three-dimensional arithmetic circuit board is configured to calculate a plurality of image data into three-dimensional size data.
The dynamic measuring device for three-dimensional dimensions according to claim 1, further comprising a lens;

The number of the lenses is the same as the number of the image sensors, and the lenses are connected to the image sensor in a one-to-one correspondence.
The dynamic measuring device for three-dimensional dimensions according to claim 2, further comprising a far-infrared filter;

The end of the lens away from the image sensor is connected to the far-infrared filter.
The dynamic measurement device for three-dimensional dimensions according to any one of claims 1 to 3, further comprising a camera mount and a camera shock absorber;

The bottom of the flat camera group is connected with the camera mounting base, and the side of the camera mounting base away from the flat camera group is connected with the camera shock absorber.
The dynamic measurement device for three-dimensional dimensions according to claim 4, wherein the camera shock absorber is provided in multiple, and the multiple camera shock absorbers are uniformly arranged along the camera mounting seat.
The dynamic measuring device for three-dimensional dimensions according to claim 4 or 5, further comprising a heat-insulating casing;

The flat camera group, the camera mounting base and the camera shock absorber are all arranged in the thermal insulation casing, and the end of the camera shock absorber away from the camera mounting base is connected to the inner wall of the thermal insulation casing;

A side of the heat-preserving casing corresponding to the image sensor is provided with first through holes, and the number of the first through holes is the same as the number of the image sensors.
The dynamic measurement device for three-dimensional dimensions according to claim 6, wherein each of the first through holes is provided with high temperature resistant tempered glass.
The dynamic measuring device for three-dimensional dimensions according to claim 6 or 7, characterized in that it further comprises a heat dissipation mechanism;

The heat-preserving casing is provided with a second through hole on a side away from the first through hole, the heat dissipation mechanism is disposed at the second through hole, and the heat-dissipating mechanism is connected to the side of the heat-preserving casing The walls are connected and configured to reduce the temperature in the thermal insulation casing.
The dynamic measurement device for three-dimensional dimensions according to any one of claims 6-8, wherein the exterior of the heat-preserving casing is covered with a heat-insulating layer.
The dynamic measuring device for three-dimensional dimensions according to any one of claims 6-9, further comprising a bracket;

The outside of one side wall of the heat-preserving casing is connected with the bracket, and the inside of the side wall of the heat-preserving casing is connected with the camera shock absorber.
The dynamic measurement device for three-dimensional dimensions according to claim 10, wherein the support includes a column and a bracket;

The bracket is slidably connected with the upright column, and the heat-preserving casing is connected with the bracket.
The dynamic measurement device for three-dimensional dimensions according to claim 11, further comprising a chassis shock absorber;

The chassis shock absorber is arranged between the heat-preserving chassis and the bracket, and the chassis shock absorber is connected to the heat-preserving chassis and the bracket respectively.
The dynamic measurement device for three-dimensional dimensions according to claim 12, wherein a plurality of said chassis shock absorbers are provided, and a plurality of said chassis shock absorbers are uniformly arranged along said bracket.
The dynamic measurement device for three-dimensional dimensions according to any one of claims 1-13, further comprising a display terminal;

The display terminal is electrically signal connected with the three-dimensional computing circuit board.
The dynamic measurement device for three-dimensional dimensions according to any one of claims 1-14, wherein the three-dimensional arithmetic circuit board adopts an FPGA (Field Programmable Gate Array) three-dimensional arithmetic circuit board.
A measuring method based on the dynamic measuring device for three-dimensional dimensions according to any one of claims 1-15, characterized in that it comprises the following steps:

Perform pairwise convolution matching operations on multiple two-dimensional images to obtain the three-dimensional coordinate positions of the edges of the object and the image feature points.
The dynamic measurement method for three-dimensional dimensions according to claim 16, characterized in that, during the image acquisition process, according to the change of the object temperature caused by the change of the image brightness, the automatic exposure parameter adjustment is performed, and the definition of the image is configured so that the sharpness of the image is not maintained. change.
The dynamic measurement method for three-dimensional dimensions according to claim 16 or 17, characterized in that it further comprises the following steps:

Establish a spatial rectangular coordinate system of multiple image sensors;

The origin of the spatial rectangular coordinate system of the plurality of image sensors is set on the plane corresponding to the focal point of the optical axis of the plurality of image sensors, and is located at the center point of the rectangular structure composed of the plurality of image sensors;

Make a unique correspondence between a group of pixels in multiple image sensors and a point on any object in space;

According to the spatial geometric constraints on multiple image sensors and the image similarity matching function, the spatial position coordinates of a point on any object in the space are obtained.
The dynamic measurement method for three-dimensional dimensions according to claim 18, wherein the step of forming a unique correspondence between a group of pixel points in the plurality of image sensors and the points further comprises:

Obtain the corresponding points in the horizontal direction of multiple image sensors corresponding to a point on any object in space, the corresponding points in the horizontal direction are located on the same horizontal scan line, and the corresponding points in the vertical direction are located on the same vertical scan line Above, the corresponding points at the diagonal positions are located on the same diagonal line, and multiple pixels simultaneously form a rectangle similar to the rectangle formed by multiple image sensors, so that the formed rectangle forms a matching spatial geometric constraint condition.
The dynamic measurement method for three-dimensional dimensions according to claim 19, further comprising the following steps: using a three-dimensional computing circuit board and adopting three-dimensional image processing software, and after the three-dimensional computing software obtains the spatial three-dimensional position coordinates of the pixels, Automatically calculate the dimensions of various forgings that need to be measured;

Among them, the three-dimensional image processing software is based on general image processing algorithms and automatic object recognition methods based on neural networks, extracts the three-dimensional size of the forging edge, automatically tracks the forging, separates the background and automatically extracts the size of the forging.