A positioning method and system for a spraying robot

Abstract

The present invention provides a positioning method and system for a spraying robot, which obtains the measurement data uploaded by the sensor; and obtains the real-time position of the sensor relative to the spraying surface of the workpiece according to the edge distance and the edge angle. Through a set of laser radar sensors, the positional relationship between the sensor and the workpiece surface is obtained, and because the installation position relationship between the sensor and the robot chassis is relatively fixed, the positional relationship between the robot chassis and the workpiece surface can be analyzed. At this time, the positioning of the robot is only related to the workpiece surface, and is not affected by external factors. There is no need for pre-scanning and mapping or manual operation (sticking magnets or ribbons). There is no need for the chassis to be positioned relative to the ground and then the mechanical arm is positioned relative to the spraying surface. The robot can adaptively spray according to the spraying surface of the workpiece, improve the positioning accuracy and stability of the spraying robot, and reduce the complexity of operation.

Description

Technical Field

[0001] The present invention relates to the field of robot control technology, and in particular to a positioning method and system for a spraying robot. Background Art

[0002] With the rapid development of science and technology, and the inevitable demand for digital transformation of enterprises. As an industrial robot for special operations, spraying robots can not only greatly reduce the labor intensity of workers and improve the working environment, but also meet the requirements of high-efficiency, environmental protection, high-quality and high-quantity spraying, which is an inevitable trend of the development of automated spraying in the future. At present, the spraying of small workpieces or specific scenes (garages, etc.) is easier to achieve, because small workpieces do not need to move, and the specific scene features are obvious and easy to locate. For large workpieces, such as bridge segments and other workpieces of tens of meters, the spraying involves the positioning and navigation of the mobile chassis relative to the spraying surface, ensuring that the spraying posture of the robotic arm conforms to the spraying path planning, otherwise it is difficult for the chassis to ensure that it is parallel to the spraying surface, resulting in spraying quality problems. Moreover, the factory buildings of such large workpieces are generally relatively open, with fewer features, and the placement of the workpieces is different each time, so a set of sensors is required to detect the workpiece features in real time so as to perform closed-loop control of the chassis position navigation in real time. However, the surface of the workpiece is generally flat, and there may be no obvious features in a large range. How to ensure that the mobile robot is positioned and navigated relative to the spraying surface when walking, so as to ensure the spraying quality, is a current technical problem.

[0003] In the existing technology, the general solutions are magnetic strips, ribbons, SLAM (Simultaneous localization and mapping, simultaneous positioning and mapping), etc. However, these methods all have the following problems: 1) The accuracy is general, usually only centimeters or even decimeters, and there is a deviation in the placement of the workpiece each time. There is an error between the workpiece coordinates and the robot map coordinates, which is difficult to detect and requires additional sensors; 2) The operation is complicated. If it is a magnetic strip or ribbon, it is necessary to re-stick it every time, and the harsh spraying environment may cause paint coverage or other interference, resulting in accuracy problems. If SLAM is used, because the factory building of large workpieces is generally large and empty, there are fewer feature points, and it may change every time the spraying is done, it is necessary to re-operate the robot to walk along the factory building to scan and build the map after each environmental change, which is complicated and troublesome to operate; 3) The stability is poor. SLAM is prone to various problems, such as positioning loss, origin loss, and difficulty in passing narrow paths. Summary of the invention

[0004] The problem to be solved by the present invention is how to improve the positioning accuracy and stability of the spraying robot and reduce the operation complexity.

[0005] To solve the above problems, on the one hand, the present invention provides a positioning method for a spraying robot, comprising:

[0006] Acquire measurement data uploaded by the sensor; wherein the measurement data includes an edge distance from the sensor to an edge position of a workpiece and an edge angle of the workpiece edge position relative to the sensor;

[0007] Obtaining a real-time position of the sensor relative to the spraying surface of the workpiece according to the edge distance and the edge angle analysis;

[0008] According to the real-time posture of the sensor and the positional relationship between the sensor and the robot chassis, the real-time posture of the chassis relative to the spraying surface of the workpiece is obtained;

[0009] Obtaining a preset path trajectory of the robot chassis, and analyzing and obtaining a control amount of chassis operation according to the preset path trajectory and the real-time position and posture of the chassis;

[0010] The operation trajectory of the robot is corrected according to the control amount of the chassis operation.

[0011] Further, the obtaining of the real-time position of the sensor relative to the spraying surface of the workpiece according to the edge distance and the edge angle analysis includes:

[0012] Obtaining the projection distance from the projection point of the sensor on the surface of the workpiece to the edge position of the workpiece according to the edge distance and the edge angle analysis;

[0013] Analyze and obtain the sensor space coordinates and the sensor rotation matrix according to the edge distance, the edge angle and the projection distance;

[0014] The real-time position and posture of the sensor relative to the spraying surface of the workpiece is obtained according to the sensor space coordinates and the sensor rotation matrix.

[0015] Further, the obtaining of the projection distance from the projection point of the sensor on the surface of the workpiece to the edge position of the workpiece according to the edge distance and the edge angle analysis includes:

[0016] In combination with the law of cosines, the projection distance from the projection point of the sensor on the surface of the workpiece to the edge position of the workpiece is obtained according to the edge distance and the edge angle analysis; wherein the projection distance is:

[0017] ;

[0018] Wherein, L1 represents the distance from the sensor projection point to the calibration edge of the workpiece; d0 represents the distance from the sensor to the workpiece surface when the sensor deflection angle is 0°; d1 represents the straight-line distance from the sensor to the calibration edge; It represents the edge angle corresponding to the calibration edge, that is, the angle between the line from the sensor to the calibration edge and d0.

[0019] Furthermore, the sensor rotation matrix is:

[0020] ;

[0021] in, 90- ');

[0022] ;

[0023] R represents the rotation matrix of the chassis around the y-axis; the forward direction of the robot chassis is defined as the positive direction. represents the angle between the forward direction of the robot chassis and the x-axis; Represents the angle between straight line L1 and d1.

[0024] Furthermore, the real-time position and posture of the sensor is: ;

[0025] in, represents the sensor rotation matrix, and P represents the sensor space coordinate;

[0026] The real-time position of the chassis is:

[0027] T0 = ;

[0028] Among them, R0 represents the chassis rotation matrix, P0 represents the spatial coordinates of the chassis, and T0' represents the rotation matrix of the sensor relative to the chassis.

[0029] Furthermore, the control amount is:

[0030] ;

[0031] Among them, u represents the control amount, t represents the real-time position of the chassis, and t=[ ,P0]', tj represents the preset path trajectory, and tj=[ j, Pj]', j is the time information, j is the angle between the forward direction of the robot chassis and the x-axis at the jth moment, Pj is the spatial coordinate of the robot chassis at the jth moment, Kp represents the gain coefficient, Kd represents the differential coefficient, dt represents the robot chassis speed or angular velocity; dtj represents the preset speed or angular velocity.

[0032] Furthermore, the positioning method of the spraying robot also includes:

[0033] According to the real-time posture of the sensor and the positional relationship between the sensor and the robot arm base, the real-time posture of the robot arm base relative to the spraying surface of the workpiece is obtained;

[0034] Obtaining a preset spraying path of the robot arm base, and analyzing and obtaining the real-time posture of the end of the robot arm according to the preset spraying path and the real-time posture of the base;

[0035] The real-time position and posture of the end of the robotic arm is sent to the robotic arm controller to control the robotic arm.

[0036] Furthermore, the real-time position and posture of the base is:

[0037] T1 = ;

[0038] Among them, R1 represents the rotation matrix of the robot base, P1 represents the spatial coordinates of the robot base, represents the sensor rotation matrix, P represents the sensor space coordinate, and T1' represents the rotation matrix of the sensor relative to the base of the robot arm.

[0039] Furthermore, the real-time posture of the end of the robotic arm is:

[0040] T=inv(T1)*Tk;

[0041] Among them, T1 represents the real-time posture of the base, and TK represents the preset spraying path of the robot arm base.

[0042] On the other hand, the present invention also provides a positioning system for a spraying robot, comprising:

[0043] A data acquisition module, used to acquire measurement data uploaded by the sensor; wherein the measurement data includes an edge distance from the sensor to an edge position of a workpiece and an edge angle of the workpiece edge position relative to the sensor;

[0044] A sensor posture analysis module, used for analyzing and obtaining a real-time posture of the sensor relative to the spraying surface of the workpiece according to the edge distance and the edge angle;

[0045] A chassis posture analysis module, used to obtain the real-time posture of the chassis relative to the spraying surface of the workpiece according to the real-time posture of the sensor and the positional relationship between the sensor and the robot chassis;

[0046] A control quantity analysis module is used to obtain a preset path trajectory of the robot chassis, and analyze and obtain the control quantity of the chassis operation according to the preset path trajectory and the real-time position and posture of the chassis;

[0047] The correction module is used to correct the running track of the robot according to the control amount of the chassis operation.

[0048] Compared with the prior art, the present invention has the following beneficial effects:

[0049] The present invention provides a positioning method and system for a spraying robot. Through, for example, a set of laser radar sensors, the positional relationship between the sensor and the surface of a workpiece can be obtained. Moreover, since the installation positional relationship between the sensor and the robot chassis is relatively fixed, the positional relationship between the robot chassis and the surface of the workpiece can be analyzed. At this time, the positioning of the robot is only related to the surface of the workpiece and is not affected by external factors. No pre-scanning and mapping or manual operation (sticking magnets or ribbons) is required. There is no need to position the chassis relative to the ground and then position the robotic arm relative to the spraying surface. The robot can adaptively perform spraying operations according to the spraying surface of the workpiece, thereby improving the positioning accuracy and stability of the spraying robot and reducing the complexity of operation. BRIEF DESCRIPTION OF THE DRAWINGS

[0050] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, a brief introduction is given below to the drawings required for use in the embodiments or the description of the prior art. Obviously, the drawings described below are some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative work.

[0051] Figure 1 The spraying flow chart of the conventional spraying robot is shown;

[0052] Figure 2 A flow chart of a method for positioning a chassis of a painting robot according to an embodiment of the present invention is shown;

[0053] Figure 3 A schematic diagram showing the positional relationship between the spraying robot and the large workpiece in an embodiment of the present invention is shown;

[0054] Figure 4 A schematic diagram of the position of the sensor in the XY plane in an embodiment of the present invention is shown;

[0055] Figure 5 A schematic diagram of the spatial position of the sensor in the XZ plane in an embodiment of the present invention is shown;

[0056] Figure 6 A schematic structural diagram of a positioning system of a spraying robot in an embodiment of the present invention is shown;

[0057] Figure 7 The working flow chart of the spraying robot in the embodiment of the present invention is shown. DETAILED DESCRIPTION

[0058] In order to make the purpose, technical solution and advantages of the embodiments of the present invention clearer, the technical solution in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0059] The specific process of traditional ribbon, magnetic stripe or slam solution is as follows Figure 1 As shown in the figure, after each workpiece is placed, manual measurement is required to attach magnetic strips or ribbons. This link requires manual operation and has poor accuracy. If SLAM is used, it may be necessary to re-map, because the piers supporting the workpiece may not be in the same position each time. The robot then needs to specify the starting position, which can be done by remote control or self-navigation, and then the spraying operation is carried out. After completion, the next workpiece is in place and the operation is repeated. The essence of these positioning methods is to position the chassis relative to the geodetic coordinate system, rather than relative to the spraying surface. If the spraying requirements are high, additional redundant sensors need to be installed on the robot arm for precise positioning of the spraying.

[0060] Figure 2 A flow chart of a method for positioning a chassis of a painting robot in an embodiment of the present invention is shown. The positioning method of the painting robot includes:

[0061] Step 1: Acquire measurement data uploaded by the sensor; wherein the measurement data includes an edge distance from the sensor to an edge position of a workpiece and an edge angle of the workpiece edge position relative to the sensor;

[0062] Step 2: Analyze and obtain the real-time position of the sensor relative to the spraying surface of the workpiece according to the edge distance and the edge angle;

[0063] Step 3: According to the real-time posture of the sensor and the positional relationship between the sensor and the robot chassis, the real-time posture of the chassis relative to the spraying surface of the workpiece is obtained;

[0064] Step 4: Obtain a preset path trajectory of the robot chassis, and analyze and obtain the control amount of the chassis operation according to the preset path trajectory and the real-time position and posture of the chassis;

[0065] Step 5: Correct the running trajectory of the robot according to the control amount of the chassis operation.

[0066] Specifically, Figure 3Taking the schematic diagram of the positional relationship between the spraying robot and the large workpiece as an example, two single-line laser radars are installed on the pillars fixed to the robot chassis. The two laser radars detect the edge of the workpiece and perform positioning and navigation. Taking the spraying of a rectangular box as an example (other complex structure workpieces can be simplified into convex bodies and decomposed into several rectangles to simplify the problem), Figure 3 In the robot chassis, two single-line laser radars are deployed horizontally and vertically, and the two laser radars complement each other. Usually, the detection radius of the laser can reach more than ten meters or even dozens of meters, so all four edges of the workpiece can be detected. The scanning frequency of the laser radar can reach tens of hertz, so the chassis can calculate based on the radar scanning information and perform closed-loop control in real time. It should be noted that the single-line radar sensor can replace any other sensor that scans the edge, and there is no restriction here.

[0067] For example, through a set of laser radar sensors, the positional relationship between the sensor and the workpiece surface can be obtained, and because the installation position relationship between the sensor and the robot chassis is relatively fixed, the positional relationship between the robot chassis and the workpiece surface can be analyzed. At this time, the positioning of the robot is only related to the workpiece surface and is not affected by external factors. There is no need for pre-scanning and mapping or manual operation (sticking magnets or ribbons). There is no need to position the chassis relative to the ground and then position the robotic arm relative to the spraying surface. The robot can adaptively spray according to the spraying surface of the workpiece, thereby improving the positioning accuracy and stability of the spraying robot and reducing the complexity of operation.

[0068] Further, step 2: obtaining the real-time position of the sensor relative to the spraying surface of the workpiece according to the edge distance and the edge angle analysis includes:

[0069] Step 20: Analyze the edge distance and the edge angle to obtain the projection distance from the projection point of the sensor on the workpiece surface to the edge position of the workpiece.

[0070] according to Figure 3 As shown in the schematic diagram of the position relationship, a spatial coordinate system is established at the vertex of the lower left corner of the box, where the origin of the coordinate system coincides with the vertex of the box, the X-axis of the coordinate system coincides with the long side of the shape, the Y-axis of the coordinate system coincides with the height of the box, and the Z-axis of the coordinate system coincides with the wide side of the box. Figure 4 A schematic diagram of the position of the sensor in the XY plane in an embodiment of the present invention is shown. From the figure, the projection distances of the sensor from the four sides of the workpiece in the xy coordinate plane are L1, L2, L3 and L4, from which it can be known that the coordinates of the sensor point P in the XY coordinate plane are (L1, L3).

[0071] Figure 5The schematic diagram of the spatial position of the sensor in the XZ plane in an embodiment of the present invention is shown. Usually, the radar will give the angle and distance information of each scanned point. The angle and distance (θ, d) of the four edge positions relative to the sensor can be easily determined through the distance mutation, as well as the distance d0 when the sensor is 0°. The forward direction and speed of the chassis are Vx.

[0072] L1-L4 can be calculated according to the law of cosines, and the projection distance from the projection point of the sensor on the workpiece surface to the edge position of the workpiece can be obtained according to the edge distance and the edge angle analysis; taking the projection distance L1 as an example:

[0073] ;

[0074] Wherein, L1 represents the distance from the sensor projection point to the calibration edge of the workpiece; d0 represents the distance from the sensor to the workpiece surface when the sensor deflection angle is 0°; d1 represents the straight-line distance from the sensor to the calibration edge; It represents the edge angle corresponding to the calibration edge, that is, the angle between the line from the sensor to the calibration edge and d0.

[0075] Step 21: Analyze and obtain sensor space coordinates and a sensor rotation matrix according to the edge distance, the edge angle, and the projection distance.

[0076] The sensor space coordinates are: ;

[0077] in, ;

[0078] Define the robot chassis forward direction as the positive direction, its rotation angle around the y-axis and the angle between the x-axis and the x-z plane are , the sensor rotation matrix around the y-axis is:

[0079] ;

[0080] in, 90- ')

[0081] R represents the rotation matrix of the chassis around the y-axis; the forward direction of the robot chassis is defined as the positive direction. represents the angle between the robot chassis forward direction Vx and the x-axis. It should be noted that Figure 5 In the figure, d0 is always perpendicular to Vx. When Vx is deflected, an angle is formed between Vx and the straight line where L1L2 is located, or Vx deviates from the straight line where L1L2 is located. Represents the angle between straight line L1 and d1.

[0082] Step 22: Obtain the real-time position and posture of the sensor relative to the spraying surface of the workpiece according to the sensor spatial coordinates and the sensor rotation matrix.

[0083] Since the sensor is fixedly connected to the chassis, in the coordinate system, the rotation matrix T0' of the chassis relative to the sensor can be calculated through the designed dimensions. Combined with the relationship between the sensor and the workpiece surface, the real-time position of the chassis relative to the workpiece surface can be further calculated as:

[0084] T0 = ;

[0085] Among them, R0 represents the chassis rotation matrix, P0 represents the spatial coordinates of the chassis, and T0' represents the rotation matrix of the sensor relative to the chassis.

[0086] In the final expression of T0, represents the real-time position of the sensor, where represents the sensor rotation matrix, and P represents the sensor space coordinate.

[0087] During the spraying process, you can use two situations: spraying while walking or spraying while stopping. Because the chassis posture can only rotate along the y-axis, the robot chassis trajectory is simplified and expressed as related to the y-axis angle and position. The robot chassis needs to plan the path trajectory tj=[ j, Pj]', where j is the time information, j represents the angle between the forward direction of the robot chassis and the y-axis at the jth moment, and Pj represents the position coordinates of the robot chassis relative to the origin of the coordinate system (i.e., the spatial coordinates of the robot chassis).

[0088] The chassis is based on the real-time posture t=[ ,P0]', It is equal to the rotation angle around the y-axis calculated in real time in the above formula. P0 is equal to the real-time position of the chassis in the above formula T0. A real-time closed loop is performed and the calculated control quantity is:

[0089] ;

[0090] Where, u represents the control amount, which can be determined according to the specific chassis input speed or torque; t=[ ,P0]' represents the real-time position of the chassis, tj=[ j, Pj]' represents the preset path trajectory, Kp represents the gain coefficient, Kd represents the differential coefficient, dt represents the derivative of the real-time posture of the chassis or the chassis speed or angular velocity; dtj represents the preset speed or angular velocity. The running trajectory of the robot is corrected according to the control amount of the chassis operation.

[0091] In one embodiment of the present invention, the positioning method of the spraying robot further includes:

[0092] Step 6: According to the real-time posture of the sensor and the positional relationship between the sensor and the robot base, the real-time posture of the robot base relative to the spraying surface of the workpiece is obtained;

[0093] Similarly, since the connection between the manipulator base and the robot base is relatively fixed, the positional relationship between the manipulator base and the sensor is fixed. By designing the dimensions, the real-time pose of the manipulator base is calculated in the same way as the above process of calculating the real-time pose of the robot chassis. The real-time pose of the manipulator base is calculated as follows:

[0094] T1 = ;

[0095] Among them, R1 represents the rotation matrix of the robot base, P1 represents the spatial coordinates of the robot base, represents the sensor rotation matrix, P represents the sensor space coordinate, and T1' represents the rotation matrix of the sensor relative to the base of the robot arm.

[0096] Step 7: Obtain a preset spraying path of the robot arm base, and analyze and obtain the real-time posture of the end of the robot arm according to the preset spraying path and the real-time posture of the base.

[0097] Similarly, the robot arm should also have a pre-planned spraying path tk=Tk, where Tk is a four-dimensional pose matrix in the same form as T1. The robot arm can be controlled by calculating the pose of the end of the robot arm relative to the base of the robot arm. At a certain moment, assuming that the real-time pose of the base of the robot arm is T1 and the pre-set spraying path is Tk, the real-time pose of the end of the robot arm is controlled as follows:

[0098] T=inv(T1)*Tk;

[0099] Among them, inv(T1) is the inverse operation of T1. T contains the position of the end of the robot arm relative to the base of the robot arm.

[0100] Step 8: The real-time position and posture of the end of the robotic arm is sent to the robotic arm controller, which can calculate the angles of each joint and control the robotic arm.

[0101] Figure 6 The figure shows a schematic diagram of the positioning system structure of a spraying robot in an embodiment of the present invention, wherein the positioning system of the spraying robot comprises:

[0102] The data acquisition module 100 is used to acquire the measurement data uploaded by the sensor; wherein the measurement data includes the edge distance from the sensor to the edge position of the workpiece and the edge angle of the workpiece edge position relative to the sensor;

[0103] A sensor posture analysis module 200, used for analyzing the edge distance and the edge angle to obtain the real-time posture of the sensor relative to the spraying surface of the workpiece;

[0104] A chassis posture analysis module 300, for obtaining the real-time posture of the chassis relative to the spraying surface of the workpiece according to the real-time posture of the sensor and the positional relationship between the sensor and the robot chassis;

[0105] The control amount analysis module 400 is used to obtain the preset path trajectory of the robot chassis, and analyze the control amount of the chassis operation according to the preset path trajectory and the real-time position and posture of the chassis;

[0106] The correction module 500 is used to correct the running trajectory of the robot according to the control amount of the chassis operation.

[0107] Figure 7 The work flow chart of the spraying robot in the embodiment of the present invention is shown, and the workpiece is placed at the specified position. At this time, the accuracy requirement for the workpiece placement is relatively loose, and the workpiece only needs to be near the specified position. At this time, the robot also starts from the starting point, and the sensor starts to measure and collect data at or before departure, and feeds the data back to the system, and corrects and adjusts the robot's path trajectory and the position and posture of the end of the robotic arm in real time. Each time, the robot only needs to step back after the spraying is completed, keep a certain distance from the workpiece, and use the sensor for positioning to ensure that the workpiece is not damaged during the placement process, thereby realizing unmanned operation.

[0108] Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or make equivalent substitutions for some of the technical features therein; and these modifications or substitutions do not make the essence of the corresponding technical solutions deviate from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. A positioning method for a spraying robot, characterized in that: include: Acquire measurement data uploaded by the sensor; wherein the measurement data includes an edge distance from the sensor to an edge position of a workpiece and an edge angle of the workpiece edge position relative to the sensor; The real-time position and posture of the sensor relative to the spraying surface of the workpiece is obtained according to the edge distance and the edge angle analysis, including: Obtaining the projection distance from the projection point of the sensor on the surface of the workpiece to the edge position of the workpiece according to the edge distance and the edge angle analysis; Analyze and obtain the sensor space coordinates and the sensor rotation matrix according to the edge distance, the edge angle and the projection distance; Obtaining the real-time position and posture of the sensor relative to the spraying surface of the workpiece according to the sensor spatial coordinates and the sensor rotation matrix; According to the real-time posture of the sensor and the positional relationship between the sensor and the robot chassis, the real-time posture of the chassis of the robot relative to the spraying surface of the workpiece is obtained; Acquire a preset path trajectory of the robot chassis, and analyze and obtain a control amount of the robot chassis operation according to the preset path trajectory and the real-time position and posture of the chassis; The operation trajectory of the robot is corrected according to the control amount of the robot chassis operation.

2. The positioning method of the spraying robot according to claim 1, characterized in that: The projected distance from the projection point of the sensor on the surface of the workpiece to the edge position of the workpiece obtained by analyzing the edge distance and the edge angle includes: Combined with the law of cosines, the projection distance from the projection point of the sensor on the surface of the workpiece to the edge position of the workpiece is obtained according to the edge distance and the edge angle analysis; wherein the projection distance is: ； Wherein, L1 represents the distance from the sensor projection point to the calibration edge of the workpiece; d0 represents the distance from the sensor to the workpiece surface when the sensor deflection angle is 0°; d1 represents the straight-line distance from the sensor to the calibration edge; It represents the edge angle corresponding to the calibration edge, that is, the angle between the line from the sensor to the calibration edge and d0.

3. The positioning method of the spraying robot according to claim 2, characterized in that: The sensor rotation matrix is: ； in, 90- '); ； R represents the sensor rotation matrix; the forward direction of the robot chassis is defined as the positive direction, represents the angle between the forward direction of the robot chassis and the x-axis; Represents the angle between straight line L1 and d1.

4. The positioning method of the spraying robot according to claim 3, characterized in that: The real-time position of the sensor is: ; in, represents the sensor rotation matrix, and P represents the sensor space coordinate; The real-time position of the chassis is: T0 = ； Among them, R0 represents the chassis rotation matrix, P0 represents the spatial coordinates of the robot chassis, and T0' represents the rotation matrix of the sensor relative to the robot chassis.

5. The positioning method of the spraying robot according to claim 4, characterized in that: The control quantity is: ； Among them, u represents the control amount, t represents the real-time position of the chassis, and t=[ ,P0]', tj represents the preset path trajectory, and tj=[ j, Pj]', j is the time information, j is the angle between the forward direction of the robot chassis and the x-axis at the jth moment, Pj is the spatial coordinate of the robot chassis at the jth moment, Kp represents the gain coefficient, Kd represents the differential coefficient, dt represents the robot chassis speed or angular velocity; dtj represents the preset speed or angular velocity.

6. The positioning method of the spraying robot according to claim 1, characterized in that: Also includes: According to the real-time posture of the sensor and the positional relationship between the sensor and the robot arm base, the real-time posture of the robot arm base relative to the spraying surface of the workpiece is obtained; Obtaining a preset spraying path of the robot arm base, and analyzing and obtaining the real-time posture of the end of the robot arm according to the preset spraying path and the real-time posture of the base; Sending the real-time position and posture of the end of the robotic arm to the robotic arm controller to control the robotic arm; Wherein, the mechanical arm base is relatively fixedly connected to the robot chassis.

7. The positioning method of the spraying robot according to claim 6, characterized in that: The real-time position of the base is: T1 = ； Among them, R1 represents the rotation matrix of the robot base, P1 represents the spatial coordinates of the robot base, represents the sensor rotation matrix, P represents the sensor space coordinate, and T1' represents the rotation matrix of the sensor relative to the base of the robot arm.

8. The positioning method of the spraying robot according to claim 7, characterized in that: The real-time position of the end of the robotic arm is: T=inv(T1)*Tk; Among them, T1 represents the real-time posture of the base, and TK represents the preset spraying path of the robot arm base.

9. A positioning system for a spraying robot, characterized in that: include: A data acquisition module, used to acquire measurement data uploaded by the sensor; wherein the measurement data includes an edge distance from the sensor to an edge position of a workpiece and an edge angle of the workpiece edge position relative to the sensor; A sensor posture analysis module, used for obtaining the real-time posture of the sensor relative to the sprayed surface of the workpiece according to the edge distance and the edge angle analysis, including: obtaining the projection distance from the projection point of the sensor on the surface of the workpiece to the edge position of the workpiece according to the edge distance and the edge angle analysis; obtaining the sensor space coordinates and the sensor rotation matrix according to the edge distance, the edge angle and the projection distance analysis; obtaining the real-time posture of the sensor relative to the sprayed surface of the workpiece according to the sensor space coordinates and the sensor rotation matrix; A chassis posture analysis module, used to obtain the real-time posture of the chassis of the robot relative to the spraying surface of the workpiece according to the real-time posture of the sensor and the positional relationship between the sensor and the robot chassis; A control quantity analysis module is used to obtain a preset path trajectory of the robot chassis, and analyze and obtain the control quantity of the robot chassis operation according to the preset path trajectory and the real-time position and posture of the chassis; The correction module is used to correct the running trajectory of the robot according to the control amount of the robot chassis operation.

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