Robot differential correction positioning method and device

Abstract

The invention relates to a robot differential correction positioning method and device. The robot differential correction positioning method comprises the following steps: calibrating a hand-eye camera and a fixed camera; the fixed camera shoots the object and the calibration plate to obtain fixed camera coordinates of the object and the reference station; the hand-eye camera shoots the calibration plate to obtain hand-eye camera coordinates of the base station; converting the object coordinates to obtain hand-eye camera coordinates of the object; and calculating a correction error between the moving station and the base station by using a differential correction algorithm, and applying the correction error to the converted object hand-eye camera coordinate. According to the robot differential correction positioning method, the object to be positioned is set as the moving station, the calibration point is set as the reference station, the coordinates of the reference station are detected while the coordinates of the object are detected, and differential correction is carried out on the coordinates of the object according to the coordinates of the reference station, so that the object coordinate detection accuracy is effectively improved, and submillimeter-level positioning is realized; and the requirement on high-precision operation is met.

Description

Technical Field

[0001] The present invention relates to the field of industrial robots, and in particular to a robot differential correction positioning method and device. Background Art

[0002] Industrial robots (or robotic arms) are an important productive force in modern factories. They are widely used in many fields such as electronics and chemical industry. They can be used not only to perform simple repetitive labor, but also to perform complex and high-precision operations. In order for robots to perform their work accurately, it is necessary to ensure that the robots can obtain accurate object coordinates. Existing technologies mainly use visual recognition, hand-eye assisted positioning and other methods to identify and obtain object coordinates. However, these methods all have certain errors, cannot achieve sub-millimeter positioning accuracy, and cannot meet the needs of high-precision processing. Summary of the invention

[0003] Based on this, the object of the present invention is to provide a robot differential correction positioning method.

[0004] A robot positioning differential correction method comprises the following steps:

[0005] S1. Calibrate the hand-eye camera and the fixed camera to obtain the transformation matrix between the hand-eye camera coordinate system, the fixed camera coordinate system and the mechanical coordinate system;

[0006] S2, establishing a template center for the object placed on the calibration plate;

[0007] S3, the fixed camera shoots the object and the calibration plate to obtain the fixed camera coordinates P of the object oc and the fixed camera coordinates P of the base station bc ;

[0008] S4. The hand-eye camera shoots the calibration plate to obtain the hand-eye camera coordinates P of the reference station. be ;

[0009] S5. Convert the object coordinates from the fixed camera coordinate system to the hand-eye camera coordinate system to obtain the object's hand-eye camera coordinates P oe ;

[0010] S6. Use the differential correction algorithm to calculate the correction error between the mobile station and the base station, and apply it to the transformed object hand-eye camera coordinate P oe superior;

[0011] S7, according to the conversion matrix E er Convert the object's hand-eye camera coordinates into mechanical coordinates to obtain the object's mechanical coordinates P or , and control the robot operation according to the mechanical coordinates.

[0012] The robot differential correction positioning method described in the present invention sets the object to be positioned as the mobile station and the calibration point as the reference station. When detecting the object coordinates, the reference station coordinates are detected at the same time, and the object coordinates are differentially corrected according to the reference station coordinates, thereby effectively improving the accuracy of object coordinate detection, realizing sub-millimeter positioning, and meeting the needs for high-precision operation.

[0013] Furthermore, the step S1 includes the following sub-steps:

[0014] S11, the robot hand-eye camera shoots the calibration plate to obtain the hand-eye camera coordinates P of the calibration point e ;

[0015] S12, calibrate the calibration plate with a fixed camera to obtain the fixed camera coordinates P of the calibration point c ;

[0016] S13, the robot moves to each calibration point of the calibration plate in turn, and obtains the mechanical coordinates P of the calibration point r ;

[0017] S14: Calculate the hand-eye camera coordinates, fixed camera coordinates and mechanical coordinates of the calibration points obtained in the above steps to obtain the transformation matrix E between the hand-eye camera coordinate system and the fixed camera coordinate system ec , and the transformation matrix E between the hand-eye camera coordinate system and the mechanical coordinate system er .

[0018] Furthermore, the step S14 is to calculate and obtain the conversion matrix according to the following formula:

[0019]

[0020] In the formula, E ce is the transformation matrix between the hand-eye camera coordinate system and the fixed camera coordinate system, for The inverse matrix of P c The transposed matrix, E er is the transformation matrix between the mechanical coordinate system and the hand-eye camera coordinate system, for The inverse matrix of P e The transposed matrix of .

[0021] Further, the step S5 is performed according to formula P oc *E ec =P oe Calculate and fix the camera coordinates P of the object oc Converted to object hand-eye-camera coordinates P oe , where E ecis the conversion matrix E obtained in step S14 ec .

[0022] Furthermore, the step S6 is to calculate the correction error according to the calculation formula:

[0023] (P oc xP bc x n ) 2 +(P oc Y bc y n ) 2 =R n 2

[0024] Where P oc x represents the object fixed camera coordinates P oc The x-coordinate, P oc y represents the object fixed camera coordinate P oc The y-coordinate of bc x n Indicates the fixed camera coordinates P of the nth base station bc The x-coordinate, P bc y n Indicates the fixed camera coordinates P of the nth base station bc The y-coordinate of n Represents the calculated correction error.

[0025] In addition, the present invention also provides a robot positioning difference correction device, comprising a robot, a calibration plate, a fixed camera and a control processing mechanism, wherein the control processing mechanism comprises

[0026] A calibration module is used to calibrate the hand-eye camera and the fixed camera to obtain the conversion matrix between the hand-eye camera coordinate system, the fixed camera coordinate system and the mechanical coordinate system;

[0027] A modeling module, used to establish a template center for an object placed on a calibration plate;

[0028] The fixed shooting module is used to control the fixed camera to shoot the object and the calibration plate to obtain the fixed camera coordinates P of the object. oc and the fixed camera coordinates P of the base station bc ;

[0029] The hand-eye shooting module is used to control the hand-eye camera to shoot the calibration plate and obtain the hand-eye camera coordinates P of the reference station. be ;

[0030] The coordinate conversion module is used to convert the object coordinates from the fixed camera coordinate system to the hand-eye camera coordinate system to obtain the object's hand-eye camera coordinates P oe;

[0031] The differential correction module is used to calculate the correction error between the mobile station and the base station using the differential correction algorithm and apply it to the transformed object hand-eye camera coordinate P oe superior;

[0032] The mechanical control module is used to calculate the conversion matrix E er Convert the object's hand-eye camera coordinates into mechanical coordinates to obtain the object's mechanical coordinates P or , and control the robot operation according to the mechanical coordinates.

[0033] Furthermore, the calibration module includes

[0034] The hand-eye camera calibration unit is used to control the robot's hand-eye camera to shoot the calibration plate and obtain the hand-eye camera coordinates P of the calibration point. e ;

[0035] The fixed camera calibration unit is used to control the fixed camera to calibrate the calibration plate and obtain the fixed camera coordinates P of the calibration point. c ;

[0036] The mechanical calibration unit is used to control the robot to run to each calibration point on the calibration plate in turn and obtain the mechanical coordinates P of the calibration point. r ;

[0037] The conversion matrix calculation unit is used to calculate the obtained calibration point hand-eye camera coordinates, fixed camera coordinates and mechanical coordinates to obtain the conversion matrix E of the hand-eye camera coordinate system and the fixed camera coordinate system. ec , and the transformation matrix E between the hand-eye camera coordinate system and the mechanical coordinate system er .

[0038] Furthermore, the conversion matrix calculation unit calculates the conversion matrix according to the formula:

[0039]

[0040] In the formula, E ce is the transformation matrix between the hand-eye camera coordinate system and the fixed camera coordinate system, for The inverse matrix of P c The transposed matrix, E er is the transformation matrix between the mechanical coordinate system and the hand-eye camera coordinate system, for The inverse matrix of P e The transposed matrix of .

[0041] Furthermore, the coordinate conversion module is based on the formula P oc*E ec =P oe Calculate and fix the camera coordinates P of the object oc Converted to object hand-eye-camera coordinates P oe , where E ec is the conversion matrix E obtained in step S14 ec .

[0042] Furthermore, the difference correction module calculates the correction error by the following formula:

[0043] (P oc xP bc x n ) 2 +(P oc Y bc y n ) 2 =R n 2

[0044] Where P oc x represents the object fixed camera coordinates P oc The x-coordinate, P oc y represents the object fixed camera coordinate P oc The y-coordinate of bc x n Indicates the fixed camera coordinates P of the nth base station bc The x-coordinate, P bc y n Indicates the fixed camera coordinates P of the nth base station bc The y-coordinate of n Represents the calculated correction error.

[0045] For better understanding and implementation, the present invention is described in detail below with reference to the accompanying drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0046] Figure 1 The present invention is a flow chart of the method. DETAILED DESCRIPTION

[0047] See also Figure 1 A robot positioning differential correction method uses a differential correction algorithm to perform differential correction on the coordinates of an object to improve the accuracy of the robot positioning object coordinates. The method comprises the following steps:

[0048] S1. Initialize the device and calibrate it using the calibration board to obtain the transformation matrix between the mechanical coordinate system and the fixed camera coordinate system. Specifically, it includes the following sub-steps:

[0049] S11, the robot hand-eye camera shoots the calibration plate to obtain the hand-eye camera coordinates P of the calibration point e .

[0050] Specifically, the calibration plate includes several calibration points. The robot hand-eye camera takes a picture of the calibration plate to obtain the coordinates of each calibration point. In this embodiment, the number of calibration points is 9, and the hand-eye camera coordinates of the calibration points are expressed as a matrix P e :

[0051]

[0052] Where P e x n , P e y n They represent the x- and y-axis coordinates of the nth calibration point in the hand-eye camera coordinate system respectively. The third column of the matrix represents the z-axis coordinate. Since the calibration points are all in the same plane, it is set to 1.

[0053] S12, calibrate the calibration plate with a fixed camera to obtain the fixed camera coordinates P of the calibration point c .

[0054] Specifically, the fixed camera is a camera fixedly installed above the loading platform and aimed at the calibration plate in the loading platform. The fixed camera shoots the calibration plate to obtain the fixed camera coordinates of each calibration point in the calibration plate. The fixed camera coordinates of the calibration point are expressed as a matrix P c :

[0055]

[0056] Where P c x n , P c y n They represent the x- and y-axis coordinates of the nth calibration point in the fixed camera coordinate system respectively. The third column of the matrix represents the z-axis coordinate. Since the calibration points are all in the same plane, it is set to 1.

[0057] S13, the robot moves to each calibration point of the calibration plate in turn, and obtains the mechanical coordinates P of the calibration point r .

[0058] Specifically, the robot moves to each calibration point on the calibration plate in turn, and records the mechanical coordinates of the current calibration point in turn to obtain the mechanical coordinate matrix P of the calibration point. r :

[0059]

[0060] Where P r x n , Pr y n They represent the x- and y-axis coordinates of the nth calibration point in the mechanical coordinate system respectively. The third column of the matrix represents the z-axis coordinate. Since the calibration points are all in the same plane, it is set to 1.

[0061] S14: Calculate the hand-eye camera coordinates, fixed camera coordinates and mechanical coordinates of the calibration points obtained in the above steps to obtain the transformation matrix E between the hand-eye camera coordinate system and the fixed camera coordinate system ec , and the transformation matrix E between the hand-eye camera coordinate system and the mechanical coordinate system er .

[0062] Specifically, the transformation matrix between the hand-eye camera coordinate system and the fixed camera coordinate system is set to E ec , then

[0063] P c *E ec =P e

[0064]

[0065] in, Indicates P c The transposed matrix of Then there is

[0066]

[0067] in, Indicates P cE The inverse matrix of . And because is equal to the identity matrix, so we have

[0068]

[0069] The hand-eye camera coordinates P of the calibration points obtained in steps S11 and S12 are e and fixed camera coordinates P c Substitute into the above formula to obtain the transformation matrix E between the hand-eye camera coordinate system and the fixed camera coordinate system ec .

[0070] Similarly, the transformation matrix E between the hand-eye camera coordinate system and the mechanical coordinate system is calculated er , thus any coordinates can be transformed in three coordinate systems through two transformation matrices.

[0071] S2, establish the template center for the object placed on the calibration plate.

[0072] S3, the fixed camera shoots the object and the calibration plate to obtain the fixed camera coordinates P of the object oc and the fixed camera coordinates P of the base stationbc .

[0073] Specifically, the calibration point of the calibration plate is set as the reference station, and the object to be positioned is set as the mobile station. The fixed camera takes pictures of the object placed on the loading platform and the calibration plate together, and obtains the coordinates of the calibration point and the object in the fixed camera coordinate system through visual recognition.

[0074] In differential correction technology, two units are set up: a mobile station and a base station. The mobile station is a movable object that needs to be corrected and positioned, and the base station is a fixed object with known accurate coordinates. When the coordinates of the mobile station and the base station are detected at the same time, the two will have the same error. At this time, the detection error can be obtained by subtracting the detection coordinates from the known accurate coordinates of the base station. The detection error is applied to the detection coordinates of the mobile station for correction to obtain more accurate mobile station coordinates.

[0075] S4, the robot hand-eye camera takes a picture of the calibration plate to obtain the hand-eye camera coordinates P of the reference station be .

[0076] Specifically, the robot hand-eye camera moves to a predetermined position, shoots the loading platform, and obtains the coordinates of the reference station of the calibration plate in the hand-eye camera coordinate system. It should be noted that since the object is placed on the calibration plate at this time, part of the reference station on the calibration plate will be blocked. In order to ensure the accuracy of detection and recognition, at least 4 reference stations need to be photographed.

[0077] S5. Fix the camera coordinates P of the object oc Convert to hand-eye camera coordinates to obtain the object hand-eye camera coordinates P oe .

[0078] Specifically, according to the calculation formula P oc *E ec =P oe Calculate and fix the camera coordinates P of the object oc Converted to object hand-eye-camera coordinates P oe , where E ec is the transformation matrix E obtained in step S1 ec .

[0079] S6. Use the differential correction algorithm to calculate the correction error between the mobile station and the base station, and apply it to the transformed object hand-eye camera coordinate P oe superior.

[0080] Specifically, there are many existing differential correction algorithms, such as linear regression, trilateration, etc. The present invention does not specifically limit the differential correction algorithm. In this embodiment, the trilateration algorithm is used as an example for calculation, according to the calculation formula:

[0081] (P oc xP bc x n ) 2 +(P oc Y bc y n ) 2 =R n 2

[0082] Where P oc x represents the object fixed camera coordinates P oc The x-coordinate, P oc y represents the object fixed camera coordinate P oc The y-coordinate of bc x n Indicates the fixed camera coordinates P of the nth base station bc The x-coordinate, P bc y n Indicates the fixed camera coordinates P of the nth base station bc The y-coordinate of n Represents the calculated correction error.

[0083] The correction error between the mobile station, that is, the object and the reference station is calculated by the above formula and applied to the transformed object hand-eye camera coordinate P oe Above, correct the coordinates obtained by directly transforming the calculation through the transformation matrix.

[0084] S7, according to the conversion matrix E er Convert the object's hand-eye camera coordinates into mechanical coordinates to obtain the object's mechanical coordinates P or , and control the robot operation according to the mechanical coordinates.

[0085] The present invention sets the calibration point of the calibration plate as the reference station and the object to be positioned as the mobile station, thereby performing differential correction on the coordinates of the mobile station by simultaneously detecting the coordinates of the mobile station and the reference station. Compared with the prior art, the method of the present invention uses the differential positioning principle to correct the coordinates of the object, which can eliminate the shooting error caused by the position deviation of the robot, provide higher-precision positioning coordinates, and meet the high-precision operation requirements.

[0086] In conjunction with the above method, the present invention also provides a robot positioning differential correction device, including a robot, a calibration plate, a fixed camera and a control processing mechanism. The robot includes a mechanical arm and a hand-eye camera, and the hand-eye camera is installed on the mechanical arm. The calibration plate is installed on a loading platform where the object to be grasped is placed, and a number of calibration points are arranged on the calibration plate. In this embodiment, the number of the calibration points is 9, and the array is arranged on the calibration plate. The installation position of the fixed camera is not limited, and it only needs to be able to clearly photograph the calibration plate. In this embodiment, the fixed camera is installed above the loading platform and is aimed at the calibration plate placed on the loading platform.

[0087] The control processing mechanism includes a calibration module, a modeling module, a fixed shooting module, a hand-eye shooting module, a coordinate conversion module, a differential correction module and a mechanical control module.

[0088] The calibration module is used to calibrate the hand-eye camera and the fixed camera to obtain a conversion matrix between the hand-eye camera coordinate system, the fixed camera coordinate system and the mechanical coordinate system.

[0089] Specifically, the calibration module includes a hand-eye camera calibration unit, a fixed camera calibration unit, a mechanical calibration unit and a transformation matrix calculation unit.

[0090] The hand-eye camera calibration unit is used to control the robot hand-eye camera to shoot the calibration plate to obtain the hand-eye camera coordinates P of the calibration point. e .

[0091] The fixed camera calibration unit is used to control the fixed camera to calibrate the calibration plate to obtain the fixed camera coordinates P of the calibration point. c .

[0092] The mechanical calibration unit is used to control the robot to run to each calibration point on the calibration plate in turn, and obtain the mechanical coordinates P of the calibration point r .

[0093] The conversion matrix calculation unit is used to calculate the obtained calibration point hand-eye camera coordinates, fixed camera coordinates and mechanical coordinates to obtain the conversion matrix E of the hand-eye camera coordinate system and the fixed camera coordinate system ec , and the transformation matrix E between the hand-eye camera coordinate system and the mechanical coordinate system er .

[0094] Specifically, the conversion matrix calculation unit is based on the formula

[0095]

[0096] Calculate the transformation matrix. In the formula, e ce is the transformation matrix between the hand-eye camera coordinate system and the fixed camera coordinate system, for The inverse matrix of P c The transposed matrix, E er is the transformation matrix between the mechanical coordinate system and the hand-eye camera coordinate system, for The inverse matrix of P e The transposed matrix of .

[0097] The modeling module is used to establish a template center for an object placed on the calibration plate.

[0098] The fixed shooting module is used to control the fixed camera to shoot the object and the calibration plate to obtain the fixed camera coordinates P of the object. oc and the fixed camera coordinates P of the base station bc .

[0099] The hand-eye shooting module is used to control the hand-eye camera to shoot the calibration plate to obtain the hand-eye camera coordinates P of the reference station. be .

[0100] The coordinate conversion module is used to convert the object coordinates from the fixed camera coordinate system to the hand-eye camera coordinate system to obtain the object's hand-eye camera coordinates P oe The coordinate conversion module is based on the formula P oc *E ec =P oe Calculate and fix the camera coordinates P of the object oc Converted to object hand-eye-camera coordinates P oe , where E ec is the conversion matrix E obtained in step S14 ec .

[0101] The differential correction module is used to calculate the correction error between the mobile station and the base station using the differential correction algorithm, and apply it to the converted object hand-eye camera coordinate P oe The differential correction module can use a variety of differential correction algorithms for calculation, for example, using a trilateral measurement algorithm to calculate the correction error through the following formula:

[0102] (P oc xP bc x n ) 2 +(P oc Y bc y n ) 2 =R n 2

[0103] Where P ocx represents the object fixed camera coordinates P oc The x-coordinate, P oc y represents the object fixed camera coordinate P oc The y-coordinate of bc x n Indicates the fixed camera coordinates P of the nth base station bc The x-coordinate, P bc y n Indicates the fixed camera coordinates P of the nth base station bc The y-coordinate of n Represents the calculated correction error.

[0104] The mechanical control module is used to convert the matrix E er Convert the object's hand-eye camera coordinates into mechanical coordinates to obtain the object's mechanical coordinates P or , and control the robot operation according to the mechanical coordinates.

[0105] The above-mentioned embodiments only express several implementation methods of the present invention, and the description is relatively specific and detailed, but it cannot be understood as limiting the scope of the invention patent. It should be pointed out that for ordinary technicians in this field, several modifications and improvements can be made without departing from the concept of the present invention, and the present invention is also intended to include these modifications and modifications.

Claims

1. A robot positioning differential correction method, characterized in that: The following steps are involved: S1. Calibrate the hand-eye camera and the fixed camera to obtain the transformation matrix between the hand-eye camera coordinate system, the fixed camera coordinate system and the mechanical coordinate system; S2, establishing a template center for the object placed on the calibration plate; S3, the fixed camera shoots the object and the calibration plate to obtain the fixed camera coordinates P of the object oc and the fixed camera coordinates P of the base station bc ; S4. The hand-eye camera shoots the calibration plate to obtain the hand-eye camera coordinates P of the reference station. be ; S5. Convert the object coordinates from the fixed camera coordinate system to the hand-eye camera coordinate system to obtain the object's hand-eye camera coordinates P oe ; S6. Use the differential correction algorithm to calculate the correction error between the mobile station and the base station, and apply it to the transformed object hand-eye camera coordinate P oe superior; S7, according to the conversion matrix E er Convert the object's hand-eye camera coordinates into mechanical coordinates to obtain the object's mechanical coordinates P or , and control the robot operation according to the mechanical coordinates.

2. The robot positioning differential correction method according to claim 1, characterized in that: The step S1 comprises the following sub-steps: S11, the robot hand-eye camera shoots the calibration plate to obtain the hand-eye camera coordinates P of the calibration point e ; S12, calibrate the calibration plate with a fixed camera to obtain the fixed camera coordinates p of the calibration point c ; S13, the robot moves to each calibration point of the calibration plate in turn, and obtains the mechanical coordinates P of the calibration point r ; S14: Calculate the hand-eye camera coordinates, fixed camera coordinates and mechanical coordinates of the calibration points obtained in the above steps to obtain the transformation matrix E between the hand-eye camera coordinate system and the fixed camera coordinate system ec , and the transformation matrix E between the hand-eye camera coordinate system and the mechanical coordinate system er .

3. The robot positioning differential correction method according to claim 2, characterized in that: The step S14 is to calculate and obtain the conversion matrix according to the following formula: In the formula, E ce is the transformation matrix between the hand-eye camera coordinate system and the fixed camera coordinate system, for The inverse matrix of P c The transposed matrix, E er is the transformation matrix between the mechanical coordinate system and the hand-eye camera coordinate system, for The inverse matrix of P e The transposed matrix of .

4. The robot positioning differential correction method according to claim 3, characterized in that: The step S5 is performed according to the formula P oc *E ec =P oe Calculate and fix the camera coordinates P of the object oc Converted to object hand-eye-camera coordinates P oe , where E ec is the conversion matrix E obtained in step S14 ec .

5. The robot positioning differential correction method according to claim 4, characterized in that: The step S6 is to calculate the correction error according to the calculation formula: (P oc x-P bc x n ) 2 +(P oc y-P bc y n ) 2 =R n 2 Where P oc x represents the object fixed camera coordinates P oc The x-coordinate, P oc y represents the object fixed camera coordinate P oc The y-coordinate of bc x n Indicates the fixed camera coordinates P of the nth base station bc The x-coordinate, P bc y n Indicates the fixed camera coordinates P of the nth base station bc The y-coordinate of n Represents the calculated correction error.

6. A robot positioning differential correction device, characterized in that: It includes a robot, a calibration plate, a fixed camera and a control processing mechanism, wherein the control processing mechanism includes A calibration module is used to calibrate the hand-eye camera and the fixed camera to obtain the conversion matrix between the hand-eye camera coordinate system, the fixed camera coordinate system and the mechanical coordinate system; A modeling module, used to establish a template center for an object placed on a calibration plate; The fixed shooting module is used to control the fixed camera to shoot the object and the calibration plate to obtain the fixed camera coordinates P of the object. oc and the fixed camera coordinates P of the base station bc ; The hand-eye shooting module is used to control the hand-eye camera to shoot the calibration plate and obtain the hand-eye camera coordinates P of the reference station. be ; The coordinate conversion module is used to convert the object coordinates from the fixed camera coordinate system to the hand-eye camera coordinate system to obtain the object's hand-eye camera coordinates P oe ; The differential correction module is used to calculate the correction error between the mobile station and the base station using the differential correction algorithm and apply it to the transformed object hand-eye camera coordinate P oe superior; The mechanical control module is used to calculate the conversion matrix E er Convert the object's hand-eye camera coordinates into mechanical coordinates to obtain the object's mechanical coordinates P or , and control the robot operation according to the mechanical coordinates.

7. The robot positioning differential correction device according to claim 6, characterized in that: The calibration module includes a hand-eye camera calibration unit, which is used to control the robot hand-eye camera to shoot the calibration plate and obtain the hand-eye camera coordinates P of the calibration point. e ; The fixed camera calibration unit is used to control the fixed camera to calibrate the calibration plate and obtain the fixed camera coordinates P of the calibration point. c ; The mechanical calibration unit is used to control the robot to run to each calibration point on the calibration plate in turn and obtain the mechanical coordinates P of the calibration point. r ; The conversion matrix calculation unit is used to calculate the obtained calibration point hand-eye camera coordinates, fixed camera coordinates and mechanical coordinates to obtain the conversion matrix E of the hand-eye camera coordinate system and the fixed camera coordinate system. ec , and the transformation matrix E between the hand-eye camera coordinate system and the mechanical coordinate system er .

8. The robot positioning difference correction device according to claim 7, characterized in that: The conversion matrix calculation unit calculates the conversion matrix according to the formula: In the formula, E ce is the transformation matrix between the hand-eye camera coordinate system and the fixed camera coordinate system, for The inverse matrix of P c The transposed matrix, E er is the transformation matrix between the mechanical coordinate system and the hand-eye camera coordinate system, for The inverse matrix of P e The transposed matrix of .

9. The robot positioning differential correction device according to claim 8, characterized in that: The coordinate conversion module is based on the formula P oc *E ec =P oe Calculate and fix the camera coordinates P of the object oc Converted to object hand-eye-camera coordinates P oe , where E ec is the conversion matrix E obtained in step S14 ec .

10. The robot positioning difference correction device according to claim 9, characterized in that: The differential correction module calculates the correction error by the following formula: (P oc x-P bc x n ) 2 +(P oc y-P bc y n ) 2 =R n 2 Where P oc x represents the object fixed camera coordinates P oc The x-coordinate, P oc y represents the object fixed camera coordinate P oc The y-coordinate of bc x n Indicates the fixed camera coordinates P of the nth base station bc The x-coordinate, P bc y n Indicates the fixed camera coordinates P of the nth base station bc The y-coordinate of n Represents the calculated correction error.

Images