A camera calibration method and system for a robotic still kettle system

Abstract

The present application relates to the technical field of camera calibration, in particular to a camera calibration method and system for a robot distillation system, wherein the camera is located above a distillation pot, and the method comprises the following steps: fixing a calibration needle on a material distribution device, establishing a first tool coordinate system with the endpoint of the calibration needle away from the material distribution device as the origin, calculating the center position of the circle where the distillation pot is located by using the equation of a circle; taking the central angle point of the calibration plate as a tool point; taking three corner points of the calibration plate as calibration points, and establishing third, fourth and fifth tool coordinate systems; offsetting each coordinate value in the center coordinates of the distillation pot according to a preset step length to obtain offset coordinates, moving the tool point to the offset coordinates, and reading the world coordinates of the tool point under the third, fourth and fifth tool coordinate systems; identifying the pixel positions of the calibration points in the image to obtain the pixel coordinates of the calibration points; and calculating the extrinsic and intrinsic parameters of the camera based on the world coordinates and the pixel coordinates. The present method can automatically calibrate, save labor, and is convenient to reuse.

Description

TECHNICAL FIELD

[0001] The application relates to the technical field of camera calibration, and in particular to a camera calibration method and system for a robot ladling system. BACKGROUND

[0002] Ladling is an important link in the operation process of the distillation link of liquor, that is, the fermented wine lees is loaded into the ladling barrel for distillation, and the wine lees needs to be spread layer by layer. The robot ladling system mainly uses an infrared camera to perceive the steam condition, and a three-dimensional camera to perceive the flatness and thickness of the material surface. For example, the patent CN118636149B, a robot ladling anti-collision method, system and device, disclosed in November 2024, first judges whether the material distribution device will collide with the ladle at the current and next material distribution positions, respectively, and whether the collision will occur during the movement, so as to select whether to execute the anti-collision planning operation. Then, in the process of executing the anti-collision planning operation, the intermediate transition point position and the corresponding Euler angle are obtained according to the current and next material distribution positions and the respective Euler angles to form a robot anti-collision scheme.

[0003] The existing technical solutions for calibrating the camera in the robot ladling system mainly adjust the posture of the calibration board, the posture of the robot, collect images, process images and calculate parameters by professional personnel. The operation is complex and tedious, time-consuming and labor-consuming, and only professional personnel can complete the calibration, resulting in high economic cost, high labor cost and high time cost of calibrating the camera parameters, and very low efficiency. SUMMARY

[0004] The application provides a camera calibration method and system for a robot ladling system.

[0005] The technical scheme of the application is as follows:

[0006] A camera calibration method for a robot ladling system, the camera is located above the ladle, and the method specifically comprises the following steps:

[0007] S1, fixing a calibration needle on the material distribution device so that the calibration needle can contact the ladle, and establishing a first tool coordinate system with the endpoint of the calibration needle away from the material distribution device as the origin, which is parallel to the robot tool coordinate system;

[0008] At the same horizontal position of the ladle rim, the endpoint of the calibration needle contacts the rim, and the contact coordinates are read under the robot base coordinate system. The center position of the circle where the contact point is located is calculated by using the equation of the circle, that is, the center of the ladle.

[0009] S2, fixing a calibration board above the material distribution device, and taking the center angle point of the calibration board as a tool point;

[0010] In addition to the center corner of the calibration plate, three corner points on the calibration plate that are not on the same straight line are taken as calibration points. The third, fourth, and fifth tool coordinate systems parallel to the robot tool coordinate system are established with the three calibration points as the origins.

[0011] S3. Heat the calibration plate. In the robot base coordinate system, move the tool point to the center of the retort pot, and keep the calibration plate parallel to the horizontal plane of the retort pot edge.

[0012] Set a step size, offset each coordinate value in the center coordinates of the steamer pot according to the preset step size to obtain a number of offset coordinates, move the tool point to an offset coordinate, take a photo to obtain an image, and read the coordinates of the tool point in the third, fourth, and fifth tool coordinate systems as world coordinates, move the tool point back to the center of the steamer pot, and repeat the steps of moving the tool point to an offset coordinate and returning to the center of the steamer pot until a threshold number of images and world coordinates are collected;

[0013] S4, identifying the pixel position of the calibration point in the image and obtaining the pixel coordinates of the calibration point;

[0014] S5. Based on the world coordinates and pixel coordinates, use Zhang Zhengyou's camera parameter calibration algorithm to calculate the camera's extrinsic and intrinsic parameters.

[0015] The first tool coordinate system with the endpoint of the calibration needle as the origin is determined in S1. The specific method is:

[0016] A reference point is fixed in the robot working area, the end point of the calibration needle is aligned with the reference point in different postures, the posture and position of the end point of the calibration needle at the reference point are collected, and the first tool coordinate system with the end point of the calibration needle as the origin is established.

[0017] The specific calculation method of the offset coordinates in S3 is:

[0018] The Cartesian coordinates of the center of the steamer pot are , the Cartesian coordinates after offset are ,but:

[0019] ,

[0020] in, 、 、 、 、 、 are the offset coefficients of ±1 and ±2 on the x, y, z, a, b, and c components of the Cartesian coordinates; 、 、 、 、 、 They correspond to the offset steps on the x, y, z, a, b, and c components of the Cartesian coordinates respectively.

[0021] The calibration plate is fixed above the material distribution device as described in S2. The specific operation is: aligning the center corner point of the calibration plate with the center point of the material distribution device.

[0022] The threshold number mentioned in S3 is 15-24.

[0023] The number of the touch point coordinates in S1 is greater than 5.

[0024] A camera calibration system for a robot retorting system, comprising:

[0025] Calibration needle: A calibration needle is fixed on the material distribution device so that the calibration needle can contact the steamer pot;

[0026] Camera; the camera is located above the steamer pot;

[0027] Calibration plate; fixed above the material distribution device;

[0028] Coordinate system establishment module: establish a first tool coordinate system with the end point of the calibration needle away from the cloth feeding device as the origin, parallel to the robot tool coordinate system; use the central corner point of the calibration plate as the tool point, and in addition to the central corner point of the calibration plate, take three corner points on the calibration plate that are not on the same straight line as calibration points, and use the three calibration points as the origin to establish the third, fourth, and fifth tool coordinate systems parallel to the robot tool coordinate system;

[0029] Data acquisition module; heating the calibration plate, moving the tool point to the center of the retort pot in the robot base coordinate system, and the calibration plate is parallel to the horizontal plane where the retort pot edge is located; setting the step size, offsetting each coordinate value in the retort pot center coordinate according to the preset step size to obtain a number of offset coordinates, moving the tool point to an offset coordinate, taking a photo to obtain an image, and reading the coordinates of the tool point in the third, fourth, and fifth tool coordinate systems as world coordinates, moving the tool point back to the center of the retort pot, and repeating the steps of moving the tool point to an offset coordinate and returning to the center of the retort pot until a threshold number of images and world coordinates are collected;

[0030] Pixel coordinate extraction module: identifies the pixel position of the calibration point in the image and obtains the pixel coordinates of the calibration point;

[0031] Parameter calculation module: Based on world coordinates and pixel coordinates, the camera's extrinsic and intrinsic parameters are calculated using Zhang Zhengyou's camera parameter calibration algorithm.

[0032] The calibration plate is fixed above the material distribution device. The specific operation is: align the center corner point of the calibration plate with the center point of the material distribution device.

[0033] The coordinate system establishment module determines the first tool coordinate system. The specific method is as follows:

[0034] Fix a reference point in the robot working area, calibrate the end point of the needle to align with the reference point in different postures, collect the posture and position of the end point of the needle at the reference point, and establish a first tool coordinate system with the end point of the needle as the origin.

[0035] The specific calculation method of the data acquisition module offset coordinates is:

[0036] The Cartesian coordinates of the retort kettle center are , and the offset Cartesian coordinates are , then:

[0037] ,

[0038] Wherein, , , , , , The offset coefficients of the x, y, z, a, b, c components of the Cartesian coordinates are ±1, ±2; , , , , , The offset steps of the x, y, z, a, b, c components of the Cartesian coordinates are respectively.

[0039] The beneficial effects of the present application are as follows:

[0040] The posture of the calibration plate, the posture of the robot, the collected image, image processing, parameter calculation and parameter updating and storage are automatically completed, which breaks through the limitation of traditional manual operation, reduces the human operation error in the automatic process, and improves the consistency of the calibration parameters;

[0041] The camera parameter calibration is automatically completed in a short time, which greatly improves the efficiency of camera calibration, and shortens the labor cost, time cost and economic cost of camera calibration. BRIEF DESCRIPTION OF DRAWINGS

[0042] In the drawings:

[0043] Figure 1 It is a camera calibration system schematic diagram of a retort system on a robot.

[0044] The reference signs are:

[0045] 1, robot; 2, retort kettle; 3, calibration plate; 4, cloth device; 5, calibration needle. DETAILED DESCRIPTION

[0046] The technical scheme of the present application is as follows:

[0047] A camera calibration method for a robot 1 steamer system is applicable to the robot 1 steamer system. The robot 1 steamer system includes a robot 1 body, which is the core execution component of the system. It usually includes a robotic arm, a drive motor, etc., and is used to realize the grasping, transportation and spreading of mash. One end is a base, and the other end is a flange, which is connected to a distribution device 4; it also includes a steamer pot 2, and the distribution device 4 contains mash. It can evenly spread the mash into the steamer pot 2 under the control of the robot 1.

[0048] The camera calibration method specifically includes the following steps:

[0049] S1. Fix a calibration pin 5 on the material distribution device 4 so that the calibration pin 5 can contact the retort 2. Establish a first tool coordinate system with the endpoint of the calibration pin 5 away from the material distribution device 4 as the origin, parallel to the tool coordinate system of the robot 1;

[0050] On the circle at the same horizontal position along the edge of the steamer pot 2, the end point of the calibration needle 5 touches the edge of the pot. In the base coordinate system of the robot 1, the coordinates of the contact point are read, and the center position of the circle where the contact point is located is calculated using the equation of the circle, which is the center of the steamer pot 2.

[0051] Furthermore, the calibration needle 5 can be installed at one end at the bottom of the material distributing device 4 and extend downward at the other end. Figure 1 , one end can also be installed at the bottom of the distribution device 4, and the other end is parallel to the plane where the steamer pot 2 is located.

[0052] The number of touch point coordinates is greater than 5, which makes it easier to determine the center position of the circle.

[0053] Determine the first tool coordinate system with the endpoint of the calibration needle 5 as the origin. The specific method is as follows:

[0054] A reference point is fixed in the working area of ​​the robot 1, the end point of the calibration needle 5 is aligned with the reference point in different postures, the posture and position of the end point of the calibration needle 5 at the reference point are collected, and a first tool coordinate system with the end point of the calibration needle 5 as the origin is established.

[0055] The specific method of establishing the coordinate system can be the three-point method or the four-point method.

[0056] A dual coordinate system is established through a physical contact calibration pin 5 to achieve spatial reference alignment between the mechanical structure and the visual system.

[0057] S2. Fix the calibration plate 3 above the material distribution device 4, with the central corner of the calibration plate 3 as the tool point;

[0058] In addition to the central corner point of the calibration plate 3, three corner points on the calibration plate 3 that are not on the same straight line are taken as calibration points. The three calibration points are used as origins to establish the third, fourth and fifth tool coordinate systems parallel to the tool coordinate system of the robot 1.

[0059] Fix the calibration plate 3 above the material distribution device 4. The specific operation is: align the central corner point of the calibration plate 3 with the central point of the material distribution device 4.

[0060] Furthermore, the calibration plate 3 is parallel to the upper surface of the material distribution device 4 .

[0061] Select three corner points on the chessboard that are not on the same straight line. These three calibration points in the calibration plate 3 determine a plane, and use the three-point teaching method to calibrate three tool coordinate systems. The number of chessboard squares in the length and width directions of the calibration plate 3 is different. Calculate whether the distance between adjacent calibration points is consistent with the distance between the corresponding corner points on the calibration plate 3 to verify whether the established tool coordinate system is correct.

[0062] After the tool coordinate system is calibrated this time, the next time calibration is performed, if the robot 1 model, the specifications of the material distribution device 4, the specifications of the calibration plate 3, the installation position of the calibration plate 3, and the fixings of the calibration plate 3 remain unchanged, the position of the tool coordinate system will not change. Therefore, the next camera calibration can use the tool coordinate system calibrated this time; in addition, for the same robot 1 model, specifications of the material distribution device 4, specifications of the calibration plate 3, the installation position of the calibration plate 3, and the fixings of the calibration plate 3, the position of the tool coordinate system is the same, and the tool coordinate system calibrated this time can also be used for relative calibration.

[0063] S3. Heat the calibration plate 3. In the base coordinate system of the robot 1, move the tool point to the center of the steamer pot 2, and make the calibration plate 3 parallel to the horizontal plane where the edge of the steamer pot 2 is located.

[0064] Set the step size, offset each coordinate value in the center coordinates of steamer pot 2 according to the preset step size to obtain several offset coordinates, move the tool point to an offset coordinate, take a photo to obtain an image, and read the coordinates of the tool point in the third, fourth, and fifth tool coordinate systems as the world coordinates, move the tool point back to the center of steamer pot 2, and repeat the steps of moving the tool point to an offset coordinate and returning to the center of steamer pot 2 until a threshold number of images and world coordinates are collected.

[0065] After the tool point is moved to the center of the steamer pot 2, there is a certain distance between the edge of the calibration plate 3 and the edge of the steamer pot 2, which does not affect the subsequent offset action.

[0066] Each coordinate value in the center coordinates of the steamer pot 2 is offset according to the preset step size, and the component of each coordinate value is adjusted by adding or subtracting the step size. The specific calculation method is:

[0067] The Cartesian coordinates of the center of the steamer pot 2 are , the offset Cartesian coordinates are , then:

[0068] ;

[0069] wherein, , , , , , are offset coefficients with values of ±1, ±2 on the x, y, z, a, b, c components of the Cartesian coordinates; , , , , , respectively correspond to the offset steps on the x, y, z, a, b, c components of the Cartesian coordinates.

[0070] The offset coordinates are stored in a position coordinate data file, a camera is controlled to take pictures to collect images, the camera collecting images includes an infrared camera and a three-dimensional camera, the images are stored in a specified folder, and are named according to a rule, to form a set of data with the world coordinates to complete storage, after the data storage is completed, a command information of data storage completion is sent, the robot 1 receives the command information, and moves the tool point to the center of the retort 2 in the robot 1 base coordinate system, the step of moving the tool point to an offset coordinate and returning to the center of the retort 2 is repeated until a threshold number, i.e. 15-24 sets of data, are collected.

[0071] The center angle point of the calibration plate 3 is moved to the adjusted new point Before that, the center angle point of the calibration plate 3 is always at the center point of the retort 2 The purpose is that the center angle point of the calibration plate 3 is at the center point of the retort 2 , the center of the calibration plate 3 coincides with the center of the retort 2, and the distance between the calibration plate 3 and the inner wall of the retort 2 is far, and a new point is obtained by small adjustment of the coordinate components From the center position of the retort 2 to the new point , the step of returning to the center of the retort 2 in the process can ensure that the calibration plate does not collide with the retort 2 and does not trigger the soft limit of the robot 1.

[0072] S4, identify the pixel position of the calibration point in the image to obtain the pixel coordinates of the calibration point.

[0073] The corner point of the calibration board 3 where the calibration point is located is the reference point in the image. All corner points of the calibration board 3 in the image collected by the camera are extracted through the corner point extraction algorithm in image processing; the number of corner points corresponding to the different numbers of grid cells in the length direction and the width direction of the calibration board 3 is different, the pixel positions of the three calibration points in the image are identified, and the corresponding pixel coordinates are extracted.

[0074] The specific method of obtaining the pixel coordinates is to establish an image coordinate system with the upper left corner of the image as the origin, the x-axis horizontally to the right, and the y-axis vertically downward, and to obtain the coordinates of the corner points in the image coordinate system in pixel units.

[0075] S5, based on the world coordinates and the pixel coordinates, the camera's external parameters and internal parameters are calculated by using the Zhang Zhengyou camera parameter calibration algorithm.

[0076] The camera external parameters are calculated according to the Zhang Zhengyou camera parameter calibration method, and the conversion formula from the world coordinates to the pixel coordinates is as follows:

[0077] ,

[0078] wherein, is a scale factor, is a pixel coordinate, is the origin coordinate of the pixel coordinate system, and are the normalized focal lengths of the x-axis and the y-axis of the image coordinate system respectively, is a world coordinate, R is a rotation scale change matrix, is a translation scale change matrix.

[0079] Further, the matrix is the camera internal parameter, and the matrix is the camera external parameter.

[0080] After the camera parameter calculation is completed, the system is requested to update the infrared camera parameters and the three-dimensional camera parameters, and the update time is stored for subsequent query and recovery; if the system does not agree to update, the camera parameters are stored in the camera parameter to be updated file, and the storage time is noted for subsequent query and update.

[0081] The posture of the calibration board 3, the posture of the robot 1, the image collection, the image processing, the parameter calculation, and the parameter updating and storage are automatically completed, breaking through the limitation of traditional manual operation, reducing the human operation error in the automatic process, and improving the consistency of the calibration parameters.

[0082] The application discloses a camera parameter automatic calibration method in a robot 1 distillation system. A calibration plate 3 with different electric heating and heat conductivity is fixed on a cloth distribution device 4, and three tool coordinate systems are established by selecting three corner point positions of small squares on a chessboard to form a plane. According to the position of a distillation pot 2 center in a robot 1 base coordinate system, the size data of the distillation pot 2, and infrared images and color images required for camera calibration, a motion point position of a center corner point of the calibration plate 3 is planned under the condition of ensuring no collision with the distillation pot 2, and the planned point position is executed in sequence. An infrared camera and a three-dimensional camera simultaneously take a group of image data every time a point position is moved, and the center corner point position coordinate data of the calibration plate 3 and the image data are stored in a specified format. After the image data collection is completed, the center corner point of the calibration plate 3 is first moved to the center point position of the distillation pot 2, and then moved to the next planned point position, and the previous operation is repeated until the number of collected images can meet the requirement of camera parameter calibration. The position coordinates of calibration points on the calibration plate 3 in the images are extracted, the world coordinates of the three tool coordinate systems at the time of collecting the corresponding images are combined, the position coordinates in the images and the corresponding world coordinates are input into a camera calibration parameter algorithm, the camera parameters are automatically calculated, and whether the existing camera parameters are replaced is reminded after the calculation is successful. Through the method, the camera calibration does not need to be operated and processed by professional personnel, the camera parameter calibration can be automatically completed within several minutes, the efficiency of the camera calibration is greatly improved, and the labor cost, time cost and economic cost of the camera calibration are reduced.

[0083] Reference Figure 1 A camera calibration system of a robot 1 distillation system, comprising:

[0084] A calibration needle 5 is fixed on the cloth distribution device 4, so that the calibration needle 5 can contact the distillation pot 2.

[0085] A camera is located above the distillation pot 2.

[0086] A calibration plate 3 is fixed above the cloth distribution device 4.

[0087] A coordinate system establishing module is used for establishing a first tool coordinate system with an endpoint of the calibration needle 5 away from the cloth distribution device 4 as an origin, and parallel to a tool coordinate system of the robot 1; taking a center corner point of the calibration plate 3 as a tool point, taking three corner points on the calibration plate 3 except the center corner point as calibration points, and establishing third, fourth and fifth tool coordinate systems parallel to the tool coordinate system of the robot 1 with the three calibration points as origins.

[0088] Data acquisition module; heating the calibration plate 3, moving the tool point to the center of the steamer pot 2 in the base coordinate system of the robot 1, and the calibration plate 3 is parallel to the horizontal plane where the pot edge of the steamer pot 2 is located; setting the step size, offsetting each coordinate value in the coordinate of the center of the steamer pot 2 according to the preset step size, obtaining a number of offset coordinates, moving the tool point to an offset coordinate, taking a photo to obtain an image, and reading the coordinates of the tool point in the third, fourth, and fifth tool coordinate systems as world coordinates, moving the tool point back to the center of the steamer pot 2, and repeating the steps of moving the tool point to an offset coordinate and returning to the center of the steamer pot 2 until a threshold number of images and world coordinates are collected;

[0089] Pixel coordinate extraction module: identifies the pixel position of the calibration point in the image and obtains the pixel coordinates of the calibration point;

[0090] Parameter calculation module: Based on world coordinates and pixel coordinates, the camera's extrinsic and intrinsic parameters are calculated using Zhang Zhengyou's camera parameter calibration algorithm.

[0091] The calibration plate 3 is fixed above the material distribution device 4. The specific operation is: align the central corner point of the calibration plate 3 with the central point of the material distribution device 4.

[0092] The coordinate system establishment module determines the first tool coordinate system. The specific method is as follows:

[0093] A reference point is fixed in the working area of ​​the robot 1, the end point of the calibration needle 5 is aligned with the reference point in different postures, the posture and position of the end point of the calibration needle 5 at the reference point are collected, and a first tool coordinate system with the end point of the calibration needle 5 as the origin is established.

[0094] The specific calculation method of the data acquisition module offset coordinates is:

[0095] The Cartesian coordinates of the center of the steamer pot 2 are , the Cartesian coordinates after offset are ,but:

[0096] ,

[0097] in, 、 、 、 、 、 are the offset coefficients of ±1 and ±2 on the x, y, z, a, b, and c components of the Cartesian coordinates; 、 、 、 、 、 They correspond to the offset steps on the x, y, z, a, b, and c components of the Cartesian coordinates respectively.

Claims

1. A camera calibration method for a robot steamer loading system, characterized in that: The camera is located above the steamer pot, and the specific steps include: S1. Fix a calibration pin on the material distribution device so that the calibration pin can contact the retort pot, and establish a first tool coordinate system with the end point of the calibration pin away from the material distribution device as the origin, parallel to the robot tool coordinate system; On the circle at the same horizontal position on the edge of the steamer pot, the end point of the calibration needle touches the edge of the pot. In the robot base coordinate system, the coordinates of the contact point are read, and the center position of the circle where the contact point is located is calculated using the equation of the circle, which is the center of the steamer pot. S2. Fix the calibration plate above the material distribution device, using the center corner of the calibration plate as the tool point; In addition to the center corner of the calibration plate, three corner points on the calibration plate that are not on the same straight line are taken as calibration points. The third, fourth, and fifth tool coordinate systems parallel to the robot tool coordinate system are established with the three calibration points as the origins. S3. Heat the calibration plate. In the robot base coordinate system, move the tool point to the center of the retort pot, and keep the calibration plate parallel to the horizontal plane of the retort pot edge. Set a step size, offset each coordinate value in the center coordinates of the steamer pot according to the preset step size to obtain a number of offset coordinates, move the tool point to an offset coordinate, take a photo to obtain an image, and read the coordinates of the tool point in the third, fourth, and fifth tool coordinate systems as world coordinates, move the tool point back to the center of the steamer pot, and repeat the steps of moving the tool point to an offset coordinate and returning to the center of the steamer pot until a threshold number of images and world coordinates are collected; S4, identifying the pixel position of the calibration point in the image and obtaining the pixel coordinates of the calibration point; S5. Based on the world coordinates and pixel coordinates, use Zhang Zhengyou's camera parameter calibration algorithm to calculate the camera's extrinsic and intrinsic parameters.

2. The camera calibration method for a robot steamer loading system according to claim 1, characterized in that: The first tool coordinate system is established in S1 with the endpoint of the calibration needle away from the material distribution device as the origin. The specific method is: A reference point is fixed in the robot working area, the end point of the calibration needle is aligned with the reference point in different postures, the posture and position of the end point of the calibration needle at the reference point are collected, and the first tool coordinate system with the end point of the calibration needle as the origin is established.

3. The camera calibration method for a robot steamer loading system according to claim 1, characterized in that: The specific calculation method of the offset coordinates in S3 is: The Cartesian coordinates of the center of the steamer pot are , the Cartesian coordinates after offset are ,but: ， in, 、 、 、 、 、 are the offset coefficients of ±1 and ±2 on the x, y, z, a, b, and c components of the Cartesian coordinates; 、 、 、 、 、 They correspond to the offset steps on the x, y, z, a, b, and c components of the Cartesian coordinates respectively.

4. The camera calibration method for a robot retorting system according to claim 1, characterized in that: The calibration plate is fixed above the material distribution device as described in S2. The specific operation is: aligning the center corner point of the calibration plate with the center point of the material distribution device.

5. The camera calibration method for a robot steamer loading system according to claim 1, characterized in that: The threshold number mentioned in S3 is 15-24.

6. The camera calibration method for a robot steamer loading system according to claim 1, characterized in that: The number of the touch point coordinates in S1 is greater than 5.

7. A camera calibration system for a robot steaming system, used to implement the camera calibration method for a robot steaming system according to claim 1, characterized in that: include: Calibration needle; A calibration pin is fixed on the material distributing device so that the calibration pin can contact the retort pot; Camera; the camera is located above the steamer pot; Calibration plate; fixed above the material distribution device; Coordinate system establishment module: establish a first tool coordinate system with the end point of the calibration needle away from the cloth feeding device as the origin, parallel to the robot tool coordinate system; use the central corner point of the calibration plate as the tool point, and in addition to the central corner point of the calibration plate, take three corner points on the calibration plate that are not on the same straight line as calibration points, and use the three calibration points as the origin to establish the third, fourth, and fifth tool coordinate systems parallel to the robot tool coordinate system; Data acquisition module; heating the calibration plate, moving the tool point to the center of the retort pot in the robot base coordinate system, and the calibration plate is parallel to the horizontal plane where the retort pot edge is located; setting the step size, offsetting each coordinate value in the retort pot center coordinate according to the preset step size to obtain a number of offset coordinates, moving the tool point to an offset coordinate, taking a photo to obtain an image, and reading the coordinates of the tool point in the third, fourth, and fifth tool coordinate systems as world coordinates, moving the tool point back to the center of the retort pot, and repeating the steps of moving the tool point to an offset coordinate and returning to the center of the retort pot until a threshold number of images and world coordinates are collected; Pixel coordinate extraction module; Identify the pixel positions of the calibration points in the image and obtain the pixel coordinates of the calibration points; Parameter calculation module: Based on world coordinates and pixel coordinates, the camera's extrinsic and intrinsic parameters are calculated using Zhang Zhengyou's camera parameter calibration algorithm.

8. The camera calibration system for a robot retorting system according to claim 7, characterized in that: The calibration plate is fixed above the material distribution device. The specific operation is: align the center corner point of the calibration plate with the center point of the material distribution device.

9. The camera calibration system for a robot retorting system according to claim 7, characterized in that: The coordinate system establishment module determines the first tool coordinate system. The specific method is as follows: A reference point is fixed in the robot working area, the end point of the calibration needle is aligned with the reference point in different postures, the posture and position of the end point of the calibration needle at the reference point are collected, and the first tool coordinate system with the end point of the calibration needle as the origin is established.

10. The camera calibration system for a robot steamer loading system according to claim 7, characterized in that: The specific calculation method of the data acquisition module offset coordinates is: The Cartesian coordinates of the center of the steamer pot are , the Cartesian coordinates after offset are ,but: ， in, 、 、 、 、 、 are the offset coefficients of ±1 and ±2 on the x, y, z, a, b, and c components of the Cartesian coordinates; 、 、 、 、 、 They correspond to the offset steps on the x, y, z, a, b, and c components of the Cartesian coordinates respectively.

Images