Double-robot grinding and polishing device based on master-slave dynamic adjustment and track control method of double-robot grinding and polishing device

Abstract

The invention relates to the field of industrial intelligent grinding and polishing machining equipment, in particular to a double-robot grinding and polishing device based on master-slave dynamic adjustment and a track control method thereof.The double-robot grinding and polishing device comprises a workbench and a six-axis robot fixedly arranged on the table top of the workbench, and the six-axis robot comprises a master robot and a slave robot; a clamping mechanical arm is arranged on the main robot, a grinding and polishing device is arranged on the auxiliary robot, the main robot and the auxiliary robot are matched with each other to conduct grinding and polishing operation on a workpiece, and a fastening clamping device is arranged at the tail end of the free end of the clamping mechanical arm. The master robot and the slave robot are controlled through a robot controller, an upper computer, the robot controller, a target ball and a calibration needle are placed on the table top of the workbench, and the problems that in the working process of an existing grinding and polishing device, the automation degree is low, a machining blind area is likely to occur, and a path is fixed and difficult to dynamically adjust are solved. And the processing efficiency and the product quality are seriously restricted.

Description

Technical Field

[0001] The present invention relates to the field of industrial intelligent grinding and polishing equipment, and in particular to a dual-robot grinding and polishing device based on master-slave dynamic adjustment and a trajectory control method thereof. Background Art

[0002] With the rapid development of modern manufacturing technology, complex three-dimensional curved surface workpieces are increasingly used in the fields of automobiles, aerospace, additive manufacturing, and mold manufacturing. Grinding and polishing technology, as a key link in achieving high-precision surface processing, has put forward higher requirements for production efficiency and product quality. However, when processing complex surfaces, traditional grinding and polishing systems have problems such as fixed paths, poor adaptability, and difficulty in real-time dynamic adjustment, which seriously affect the processing efficiency and quality. Therefore, in order to complete the grinding and polishing tasks comprehensively, efficiently, and accurately, it is urgent to develop an efficient, high-precision, and flexible dual-robot automatic grinding and polishing system.

[0003] The intelligent robot grinding and polishing device is an advanced equipment that integrates multiple technologies such as robot technology, intelligent control, and grinding and polishing processes. It is widely used in the manufacturing industry to perform high-precision and high-quality grinding and polishing on the surface of workpieces.

[0004] The intelligent robot grinding and polishing device is mainly composed of the following parts: grinding and polishing tools, robot body, control system, vision system and force control system. Compared with traditional grinding and polishing devices, its advantage lies in the integration of intelligent control system and the use of robots and mechanical arms to replace lathes, thereby improving the accuracy of grinding and polishing. On the one hand, it ensures stable product quality, and on the other hand, it can adapt to more complex workpieces.

[0005] The invention patent of Chinese patent application No. 202311626651.7 discloses a robot processing system and method integrating line measurement, grinding, polishing and final inspection. The system includes a robot grinding and polishing workstation, a workpiece transfer station and a final inspection workstation which are communicatively connected to the master control device; the robot grinding and polishing workstation includes a line laser online detection mechanism, a full-feature force-speed collaborative processing mechanism, a full-feature belt grinding and polishing mechanism, an industrial robot and a loading unit; the loading unit is provided with a zero-point tooling matching the workpiece; the workpiece transfer station includes a transfer fixing plate, a transfer door, a transfer station clamp and a transfer unloading table; the full-feature force-speed collaborative processing mechanism and the full-feature belt grinding and polishing mechanism are controlled by the master control device to perform full-feature precision grinding and polishing on complex curved surface workpieces, the line laser online detection mechanism is used to perform online detection on the workpiece clamped by the industrial robot, and the processing process parameters are calculated and adjusted, and a three-coordinate measuring instrument is used to perform final inspection on the workpiece to achieve full-feature high-efficiency grinding and polishing of complex curved surface workpieces. The technical solution proposed by the above invention solves the problem that it is impossible to detect and adjust parameters online in real time during the grinding and polishing of complex curved workpieces, and it is difficult to ensure the quality and efficiency of grinding and polishing through line laser online detection, full-feature force-speed coordinated processing and full-feature belt grinding and polishing, combined with the final inspection of the three-coordinate measuring instrument, and realizes one-time processing and forming, effectively improving the processing quality and efficiency of complex curved blade parts, and reducing clamping errors and dust effects. However, the technical solution proposed by the above invention and the existing solutions still have many limitations when facing these complex processing tasks: 1. The robot grinding and polishing system has a low degree of automation.

[0006] 2. Use a single robot or CNC machine tool to grind complex three-dimensional curved surface workpieces. Due to the limitations of the equipment's own freedom and operability, omissions and processing blind spots are prone to occur.

[0007] 3. Although the dual-robot collaborative grinding and polishing system has certain flexibility and efficiency improvements compared to a single robot, most systems still perform processing through fixed programs or simple trajectories, which makes it difficult to meet the high-precision and high-quality requirements of complex surface processing. Summary of the invention

[0008] Therefore, in response to the above problems, the present invention proposes a dual-robot grinding and polishing device based on master-slave dynamic adjustment and a trajectory control method thereof, which solves the problems of low degree of automation, easy occurrence of processing blind spots, and difficult dynamic adjustment of fixed paths during the operation of existing grinding and polishing devices, which seriously restricts processing efficiency and product quality.

[0009] To achieve the above-mentioned objectives, the present invention adopts the following technical scheme: a dual-robot grinding and polishing device based on master-slave dynamic adjustment, comprising a workbench, a six-axis robot fixedly arranged on the table top of the workbench, the six-axis robot comprising a master robot and a slave robot, the master robot is provided with a clamping manipulator, the slave robot is provided with a grinding and polishing device, the master robot and the slave robot cooperate with each other to perform grinding and polishing operations on the workpiece, the free end of the clamping manipulator is provided with a fastening clamping device, the master robot and the slave robot are controlled by a robot controller, and a host computer, a robot controller, a target ball, and a calibration needle are placed on the table top of the workbench.

[0010] Furthermore, the grinding and polishing device includes an air motor, a coupling, a grinding wheel, a polishing disk, a fastening clamp, a pressure sensor, and a line laser measuring instrument. The grinding and polishing device is arranged at the free end of the slave robot and is connected through a universal swivel. The pressure sensor is arranged on the universal swivel. The air motor is connected to the universal swivel through a fastening clamp, and the grinding wheel is connected to the air motor through the coupling.

[0011] Furthermore, the fastening and clamping device includes a fixed base and a clamping claw arranged on the fixed base, a positioning slot is arranged on the outer surface of the fixed base, the clamping claw is arranged on the inner side surface of the positioning slot, the clamping claw is parallel to the inner bottom surface of the positioning slot, and a receiving platform is arranged on the inner bottom surface of the positioning slot. The receiving platform is used to place the workpiece, and the receiving platform can rotate 360° along its own axis. The clamping claw is arranged in a surrounding shape, and an electromagnet magnetic attraction device is arranged in the receiving platform, and the surface of the receiving platform is a frosted surface.

[0012] Furthermore, the clamping claw is driven to extend and retract by a motor, and moves closer to or away from the receiving platform in the horizontal direction. A sliding ball is provided at the free end of the clamping claw, and the sliding ball is covered with a rubber layer.

[0013] A trajectory control method for a dual-robot grinding and polishing device based on master-slave dynamic adjustment comprises the following steps: S1, system spatial position calibration; S2, collection and processing of workpiece three-dimensional data; S3, planning the processing trajectory; S4, start grinding and polishing; the two robots cooperate to control and perform the grinding and polishing task; S5, grinding and polishing inspection; after the grinding and polishing task is completed, the slave robot carries a line laser measuring instrument to inspect the processed workpiece. If the point cloud data is consistent with the standard model, the processing is completed. If not, repeat steps S3 and S4 until the standard is met.

[0014] Furthermore, step S1 includes the following subdivision steps: S1.1 Calibration of the dual robot base coordinate system; by installing calibration needles at the ends of the master robot and the slave robot to reach the same point in space multiple times in a "handshake" manner, a calibration matrix equation is established to directly obtain the coordinate transformation between the two robot bases; determine the transformation relationship between the two robot base coordinate systems and the global coordinate system, and transform them to the same coordinate system; S1.2. Dual robot TCP calibration; TCP is calibrated by the seven-point method. The calibration needle is installed on the end of the master and slave robots to reach the same point in space in four different postures. The simultaneous equations are obtained by the least squares method to obtain the position relationship of TCP relative to the end of the master and slave robots. Similarly, the posture relationship of the master and slave robots is obtained, and thus the position and posture relationship of TCP with respect to the end is obtained; the conversion relationship between the tool coordinate system and the base coordinate system is determined, and they are converted to the same coordinate system; S1.3, hand-eye calibration; the line laser measuring instrument is fixed at the end of the slave robot, and a standard ball is used as a target. The slave robot is controlled to measure the target fixed in the working area of ​​the slave robot in different postures, and the hand-eye matrix is ​​solved according to the constraint relationship that the center of the ball remains unchanged in space; thereby realizing the conversion between the measurement coordinate system and the slave robot coordinate system, and converting them to the same coordinate system.

[0015] Furthermore, in step S2, a polishing robot with a line laser measuring instrument is used to scan all contours of the surface of the workpiece to be processed, and point cloud data of the contour of the surface of the workpiece to be processed is obtained from the line laser measuring instrument. The point cloud data is denoised once using statistical filtering, and then denoised twice using radius filtering. The point cloud data is smoothed using a bilateral filtering algorithm, and finally the point cloud data is simplified using an angle deviation method, so as to obtain more accurate and precise point cloud data of the contour of the surface of the workpiece to be processed. The collection and synchronization of real-time data include: S2.1. Fix the line laser measuring instrument at the end of the slave robot and synchronize its position and posture with the gripping manipulator of the master robot through the EtherCAT bus. S2.2. Collect the point cloud data of the workpiece surface, eliminate noise and simplify it through bilateral filtering algorithm and angle deviation algorithm.

[0016] Furthermore, step S3 includes the following subdivision steps: S3.1. Planning of machining trajectory for grinding tasks. By comparing the processed point cloud data with the standard model, the machining allowance and coordinate information are obtained, and the machining path is formed according to polynomial curve fitting. S3.2. In the planning of machining trajectories for complex grinding and polishing of workpiece surfaces, a high-degree-of-freedom industrial robot and a flexible grinding tool head are used to simulate the manual surface grinding and polishing process, combining manual experience with geometric feature analysis to plan a reasonable robot grinding and polishing path; According to the master-slave control method, the robot holding the workpiece is selected as the master robot, and the grinding robot is selected as the slave robot. The master robot plans according to the expected trajectory according to the grinding and polishing task requirements. The motion trajectory of the slave robot ensures constant force grinding and polishing, which is obtained through the pressure sensor and calculated according to the closed-chain motion constraint relationship of the collaborative system; Among them, algorithm optimization is performed for dynamic trajectories, including real-time error feedback and model predictive control optimization; Real-time error feedback: Compare the measured data with the standard model and calculate the local margin deviation:

[0017] When the average deviation of the region When trigger adjustment; Model predictive control optimization: Establish the robot kinematic model and grinding and polishing force model, and generate the optimal adjustment through rolling time domain optimization:

[0018] Among them, y(k) is the actual trajectory, yref(k) is the reference trajectory, u(k) is the control input, and λ is the weight coefficient; Fault-tolerance mechanism: When the master robot's posture adjustment exceeds the limit, the slave robot is triggered to pause and wait for re-planning the path.

[0019] Furthermore, in step S4, the main robot holding the workpiece moves according to a predetermined trajectory, and the slave robot performs constant force grinding according to the obtained trajectory. At the same time, the line laser measuring instrument measures the contour data of the workpiece surface in real time, and transmits the contour data to the GUI interface. The GUI compares the transmitted contour data with the contour data of the standard model, adjusts the processing trajectory of the slave robot online in real time, and then outputs it to the slave robot controller to fine-tune the processing trajectory of the slave robot; when there is inconsistency with the expected model, the information is sent to the host computer in time, and the host computer controls the robot controller to make the dual robots stop urgently.

[0020] Furthermore, in step S4, the main robot performs dynamic posture optimization in real time, and calculates the optimization direction of the main robot's clamping posture in real time based on the workpiece geometric model and the robot kinematic model:

[0021] Among them, θ is the joint angle of the master robot, J(qi) is the Jacobian matrix condition number of the slave robot at the i-th path point, maximizing the overall motion flexibility; The slave robot coordinates motion control and establishes the kinematic constraint relationship between the master and slave robots:

[0022] Among them, R1 and R2 represent the base coordinate systems of the master robot and the slave robot respectively, E1 and E2 represent the end coordinate systems of the two robots respectively, T1 and T2 represent the workpiece clamping tool coordinate system and the grinding tool coordinate system respectively, and w represents the workpiece coordinate system.

[0023] By adopting the above technical solution, the beneficial effects of the present invention are: 1. The present invention proposes a dual-robot intelligent grinding and polishing device for complex processing paths. Through efficient and accurate calibration methods, real-time optimized trajectory planning and intelligent control strategies, high-precision grinding and polishing of complex workpiece surfaces are achieved. The system can flexibly adjust the processing path according to the needs of different materials and complex geometric shapes, and combine online measurement with standard model comparison technology for real-time optimization to ensure processing quality while avoiding large deviations from causing damage to equipment and products. In addition, the dual-robot collaborative control mode not only improves processing efficiency and consistency, but also ensures the safety and reliability of operations through advanced safety protection mechanisms and closed-chain motion constraint algorithms. The invention has significant advantages in intelligence, adaptability, accuracy and economy, and provides an efficient and reliable solution for industrial automation precision manufacturing, especially suitable for the field of grinding complex curved workpieces with high precision requirements.

[0024] 2. In the present invention, a fastening clamping device is provided at the free end of the clamping manipulator, so that the fastening clamping device can provide a stable clamping operation for the workpiece, and the workpiece is placed in a positioning slot of a fixed base, and the positioning slot provides preliminary positioning for the workpiece, and specifically provides a clamping operation for the workpiece through the clamping claws in the positioning slot. When the workpiece is placed on the receiving table in the positioning slot, after the electromagnet magnetic attraction device on the receiving table is turned on, the workpiece and the receiving table are magnetically matched, and then the clamping claws approach the center of the receiving table to clamp the workpiece. When performing grinding and polishing operations, the receiving table rotates 360° to drive the workpiece to rotate. During the rotation process, the clamping claws are linked according to the shape and specifications of the workpiece, and are extended and retracted in real time to adapt to the rotation of the workpiece. At the same time, since a sliding ball is provided at the free end thereof, the sliding ball is also provided for the purpose of cooperating with the rotation of the workpiece, ensuring that the clamping claws can always fit the workpiece no matter how the workpiece rotates under the action of the sliding ball, so as to achieve stable clamping.

[0025] 3. In the present invention, the sliding ball is covered with a rubber layer. The purpose of the rubber layer is, on the one hand, to protect the outer surface of the workpiece from being damaged during the clamping process, and on the other hand, to buffer the vibration generated during the grinding and polishing process. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] Other features, objects and advantages of the present invention will become more apparent from the detailed description of non-limiting embodiments made with reference to the following drawings: Figure 1 It is a schematic diagram of the three-dimensional structure of the present invention; Figure 2 This is a schematic diagram of the front structure of the six-axis robot of the present invention; Figure 3 It is a front structural schematic diagram of the fastening and clamping device of the present invention; Figure 4 for Figure 2 Enlarged view of point A in the middle; Figure 5 The overall working flow diagram of the dual robot grinding and polishing system of the present invention; Figure 6 This is a flow chart of point cloud data processing and trajectory planning in the present invention; Figure 7 Schematic diagram of the coordination constraint relationship of the two robots in the present invention. DETAILED DESCRIPTION

[0027] In order to make the technical means, creative features, objectives and effects achieved by the present invention easy to understand, the present invention is further explained below in conjunction with specific implementation methods.

[0028] See also Figure 1-Figure 7 The present invention provides a dual-robot grinding and polishing device based on master-slave dynamic adjustment, comprising a workbench 1, a six-axis robot fixedly arranged on the table of the workbench 1, the six-axis robot comprising a master robot 2 and a slave robot 3, the master robot 2 is provided with a clamping manipulator 4, the slave robot 3 is provided with a grinding and polishing device 5, the master robot 2 and the slave robot 3 cooperate with each other to perform grinding and polishing operations on the workpiece, the free end of the clamping manipulator 4 is provided with a fastening clamping device 9, the master robot 2 and the slave robot 3 are controlled by a robot controller 6, and a host computer 8, a robot controller 6, a target ball 7, and a calibration needle are placed on the table of the workbench 1; The grinding and polishing device 5 includes an air motor 53, a coupling 52, a grinding wheel 51, a polishing disc, a fastening fixture 54, a pressure sensor 55, and a line laser measuring instrument 56. The grinding and polishing device 5 is arranged at the free end of the slave robot 3 and is connected through a universal swivel. The pressure sensor 55 is arranged on the universal swivel. The air motor 53 is connected to the universal swivel through the fastening fixture 54. The grinding wheel 51 is connected to the air motor 53 through the coupling 52. The working principle of the grinding and polishing device 5 is well known, and only intelligent electrical control is added, which will not be elaborated here.

[0029] The fastening clamping device 9 includes a fixed base 91 and a clamping claw 92 arranged on the fixed base 91. A positioning slot 911 is arranged on the outer surface of the fixed base 91. The clamping claw 92 is arranged on the inner side of the positioning slot 911. The clamping claw 92 is parallel to the inner bottom surface of the positioning slot 911. The inner bottom surface of the positioning slot 911 is provided with a receiving platform 93. The receiving platform 93 is used to place the workpiece. The receiving platform 93 can rotate 360° along its own axis. The clamping claw 92 is arranged in a surrounding shape. An electromagnet magnetic attraction device 94 is arranged in the receiving platform 93. The surface of the receiving platform 93 is a frosted surface, which can provide greater friction for the workpiece.

[0030] The clamping claw 92 is driven by a motor to extend and retract, and is moved closer to or away from the receiving platform 93 in the horizontal direction. A sliding ball 921 is provided at the free end of the clamping claw 92, and the sliding ball 921 is coated with a rubber layer. The rubber layer is coated by hot-melt coating.

[0031] This embodiment simultaneously proposes a trajectory control method for the above-mentioned grinding and polishing device, a trajectory control method for a dual-robot grinding and polishing device based on master-slave dynamic adjustment, comprising the following steps: S1, system spatial position calibration; S2, collection and processing of workpiece three-dimensional data; S3, planning the processing trajectory; S4, start grinding and polishing; the two robots cooperate to control and perform the grinding and polishing task; S5, grinding and polishing inspection; after the grinding and polishing task is completed, the slave robot carries a line laser measuring instrument 56 to inspect the processed workpiece. If the point cloud data is consistent with the standard model, the processing is completed. If not, steps S3 and S4 are repeated until the standard is met.

[0032] Wherein, step S1 includes the following subdivision steps: S1.1 Calibration of the dual robot base coordinate system; by installing calibration needles at the ends of the master robot 2 and the slave robot 3 to reach the same point in space multiple times in a "handshake" manner, a calibration matrix equation is established to directly obtain the coordinate transformation between the two robot bases; determine the transformation relationship between the two robot base coordinate systems and the global coordinate system, and transform them to the same coordinate system; S1.2. Dual robot TCP calibration; TCP is calibrated by the seven-point method. The calibration needle is installed on the end of the master and slave robots to reach the same point in space in four different postures. The simultaneous equations are obtained by the least squares method to obtain the position relationship of TCP relative to the end of the master and slave robots. Similarly, the posture relationship of the master and slave robots is obtained, and thus the position and posture relationship of TCP with respect to the end is obtained; the conversion relationship between the tool coordinate system and the base coordinate system is determined, and they are converted to the same coordinate system; S1.3, hand-eye calibration; the line laser measuring instrument 56 is fixed at the end of the slave robot, and a standard ball is used as a target. The slave robot is controlled to measure the target fixed in the working area of ​​the slave robot in different postures, and the hand-eye matrix is ​​solved according to the constraint relationship that the position of the center of the ball in space remains unchanged; thereby realizing the conversion between the measurement coordinate system and the slave robot coordinate system, and converting them to the same coordinate system.

[0033] In step S2, the polishing robot with the line laser measuring instrument 56 is used to scan the entire contour of the surface of the workpiece to be processed, and the point cloud data of the contour of the surface of the workpiece to be processed is obtained from the line laser measuring instrument 56. The point cloud data is denoised once using statistical filtering, and then denoised twice using radius filtering. The point cloud data is smoothed using a bilateral filtering algorithm, and finally the point cloud data is simplified using an angle deviation method, so as to obtain more accurate and precise point cloud data of the contour of the surface of the workpiece to be processed; The collection and synchronization of real-time data include: S2.1, fix the line laser measuring instrument 56 at the end of the slave robot, and achieve posture synchronization with the gripping manipulator 4 of the master robot 2 through the EtherCAT bus; S2.2. Collect the point cloud data of the workpiece surface, eliminate noise and simplify it through bilateral filtering algorithm and angle deviation algorithm.

[0034] Step S3 includes the following subdivision steps: S3.1. Planning of machining trajectory for grinding tasks. By comparing the processed point cloud data with the standard model, the machining allowance and coordinate information are obtained, and the machining path is formed according to polynomial curve fitting. S3.2. In the planning of machining trajectories for complex grinding and polishing of workpiece surfaces, a high-degree-of-freedom industrial robot and a flexible grinding tool head are used to simulate the manual surface grinding and polishing process, combining manual experience with geometric feature analysis to plan a reasonable robot grinding and polishing path; According to the master-slave control method, the robot holding the workpiece is selected as the master robot, and the grinding robot is selected as the slave robot. The master robot plans according to the expected trajectory according to the grinding and polishing task requirements. The motion trajectory of the slave robot ensures constant force grinding and polishing, which is obtained through the pressure sensor and calculated according to the closed-chain motion constraint relationship of the collaborative system; Among them, algorithm optimization is performed for dynamic trajectories, including real-time error feedback and model predictive control optimization; Real-time error feedback: Compare the measured data with the standard model and calculate the local margin deviation:

[0035] When the average deviation of the region When trigger adjustment; Model predictive control optimization: Establish the robot kinematic model and grinding and polishing force model, and generate the optimal adjustment through rolling time domain optimization:

[0036] Among them, y(k) is the actual trajectory, yref(k) is the reference trajectory, u(k) is the control input, and λ is the weight coefficient; Fault-tolerance mechanism: When the master robot's posture adjustment exceeds the limit, the slave robot is triggered to pause and wait for re-planning the path.

[0037] In step S4, the main robot holding the workpiece moves according to a predetermined trajectory, and the slave robot performs constant force grinding according to the obtained trajectory. At the same time, the line laser measuring instrument measures the contour data of the workpiece surface in real time and transmits the contour data to the GUI interface. The GUI compares the transmitted contour data with the contour data of the standard model, adjusts the processing trajectory of the slave robot online in real time, and then outputs it to the slave robot controller to fine-tune the processing trajectory of the slave robot; when there is inconsistency with the expected model, the information is sent to the host computer in time, and the host computer controls the robot controller to make the dual robots stop urgently.

[0038] Furthermore, in step S4, the main robot performs dynamic posture optimization in real time, and calculates the optimization direction of the main robot's clamping posture in real time based on the workpiece geometric model and the robot kinematic model:

[0039] Among them, θ is the joint angle of the master robot, J(qi) is the Jacobian matrix condition number of the slave robot at the i-th path point, maximizing the overall motion flexibility; The slave robot coordinates motion control and establishes the kinematic constraint relationship between the master and slave robots:

[0040] Among them, R1 and R2 represent the base coordinate systems of the master robot and the slave robot respectively, E1 and E2 represent the end coordinate systems of the two robots respectively, T1 and T2 represent the workpiece clamping tool coordinate system and the grinding tool coordinate system respectively, and w represents the workpiece coordinate system.

[0041] The above shows and describes the basic principles and main features of the present invention and the advantages of the present invention. It is obvious to those skilled in the art that the present invention is not limited to the details of the above exemplary embodiments, and the present invention can be implemented in other specific forms without departing from the spirit or basic features of the present invention. Therefore, no matter from which point of view, the embodiments should be regarded as exemplary and non-restrictive. The scope of the present invention is defined by the attached claims rather than the above description, and it is intended that all changes falling within the meaning and scope of the equivalent elements of the claims are included in the present invention. Any figure mark in the claims should not be regarded as limiting the claims involved.

[0042] In addition, it should be understood that although the present specification is described according to implementation modes, not every implementation mode contains only one independent technical solution. This description of the specification is only for the sake of clarity. Those skilled in the art should regard the specification as a whole. The technical solutions in each embodiment may also be appropriately combined to form other implementation modes that can be understood by those skilled in the art.

Claims

1. A dual-robot grinding and polishing device based on dynamic adjustment of master and slave, comprising a workbench and a six-axis robot fixedly arranged on the workbench, characterized in that: The six-axis robot comprises a master robot and a slave robot, the master robot is provided with a clamping manipulator, the slave robot is provided with a grinding and polishing device, the master robot and the slave robot cooperate with each other to perform grinding and polishing operations on the workpiece, the free end of the clamping manipulator is provided with a fastening clamping device, the master robot and the slave robot are controlled by a robot controller, and a host computer, a robot controller, a target ball, and a calibration needle are placed on the table of the workbench; The grinding and polishing device includes an air motor, a coupling, a grinding wheel, a polishing disc, a fastening fixture, a pressure sensor, and a line laser measuring instrument. The grinding and polishing device is arranged at the free end of the slave robot and connected through a universal swivel. The pressure sensor is arranged on the universal swivel. The air motor is connected to the universal swivel through a fastening fixture, and the grinding wheel is connected to the air motor through the coupling. The fastening clamping device comprises a fixed base, a clamping claw arranged on the fixed base, a positioning slot is arranged on the outer surface of the fixed base, the clamping claw is arranged on the inner side of the positioning slot, the clamping claw is parallel to the inner bottom surface of the positioning slot, a receiving platform is arranged on the inner bottom surface of the positioning slot, the receiving platform is used to place the workpiece, the receiving platform can rotate 360° along its own axis, the clamping claw is arranged in a surrounding shape, an electromagnet magnetic attraction device is arranged in the receiving platform, and the surface of the receiving platform is a frosted surface; The clamping claw is driven to extend and retract by a motor, and moves closer to or away from the receiving platform in the horizontal direction. A sliding ball is arranged at the free end of the clamping claw, and the sliding ball is covered with a rubber layer.

2. A trajectory control method for a dual-robot grinding and polishing device based on master-slave dynamic adjustment as claimed in claim 1, characterized in that: The following steps are involved: S1, system spatial position calibration; S2, collection and processing of workpiece three-dimensional data; S3, planning the processing trajectory; S4, start grinding and polishing; the two robots cooperate to control and perform the grinding and polishing task; S5, grinding and polishing inspection; after the grinding and polishing task is completed, the slave robot carries a line laser measuring instrument to inspect the processed workpiece. If the point cloud data is consistent with the standard model, the processing is completed. If not, repeat steps S3 and S4 until the standard is met.

3. The trajectory control method of the dual robot grinding and polishing device based on master-slave dynamic adjustment according to claim 2 is characterized in that: Step S1 includes the following subdivision steps: S1.1 Calibration of the dual robot base coordinate system; by installing calibration needles at the ends of the master robot and the slave robot to reach the same point in space multiple times in a "handshake" manner, a calibration matrix equation is established to directly obtain the coordinate transformation between the two robot bases; determine the transformation relationship between the two robot base coordinate systems and the global coordinate system, and transform them to the same coordinate system; S1.

2. Dual robot TCP calibration; TCP is calibrated by the seven-point method. The calibration needle is installed on the end of the master and slave robots to reach the same point in space in four different postures. The simultaneous equations are obtained by the least squares method to obtain the position relationship of TCP relative to the end of the master and slave robots. Similarly, the posture relationship of the master and slave robots is obtained, and thus the position and posture relationship of TCP with respect to the end is obtained; the conversion relationship between the tool coordinate system and the base coordinate system is determined, and they are converted to the same coordinate system; S1.3, hand-eye calibration; The line laser measuring instrument is fixed at the end of the slave robot. A standard ball is used as a target. The slave robot is controlled to measure the target fixed in the working area of ​​the slave robot in different postures, and the hand-eye matrix is ​​solved according to the constraint relationship that the position of the center of the ball in space remains unchanged; thereby realizing the conversion between the measurement coordinate system and the slave robot coordinate system, and converting them to the same coordinate system.

4. The trajectory control method of the dual robot grinding and polishing device based on master-slave dynamic adjustment according to claim 3 is characterized in that: In step S2, a polishing robot with a line laser measuring instrument is used to scan the entire contour of the surface of the workpiece to be processed, and point cloud data of the surface contour of the workpiece to be processed is obtained from the line laser measuring instrument. The point cloud data is denoised once using statistical filtering, and then denoised twice using radius filtering. The point cloud data is smoothed using a bilateral filtering algorithm, and finally the point cloud data is simplified using an angle deviation method, so as to obtain more accurate and precise point cloud data of the surface contour of the workpiece to be processed; The collection and synchronization of real-time data include: S2.

1. Fix the line laser measuring instrument at the end of the slave robot and synchronize its position and posture with the gripping manipulator of the master robot through the EtherCAT bus. S2.

2. Collect the point cloud data of the workpiece surface, eliminate noise and simplify it through bilateral filtering algorithm and angle deviation algorithm.

5. The trajectory control method of the dual robot grinding and polishing device based on master-slave dynamic adjustment according to claim 4 is characterized in that: Step S3 includes the following subdivision steps: S3.

1. Planning of machining trajectory for grinding tasks. By comparing the processed point cloud data with the standard model, the machining allowance and coordinate information are obtained, and the machining path is formed according to polynomial curve fitting. S3.

2. In the planning of machining trajectories for complex grinding and polishing of workpiece surfaces, a high-degree-of-freedom industrial robot and a flexible grinding tool head are used to simulate the manual surface grinding and polishing process, combining manual experience with geometric feature analysis to plan a reasonable robot grinding and polishing path; According to the master-slave control method, the robot holding the workpiece is selected as the master robot, and the grinding robot is selected as the slave robot. The master robot plans according to the expected trajectory according to the grinding and polishing task requirements. The motion trajectory of the slave robot ensures constant force grinding and polishing, which is obtained through the pressure sensor and calculated according to the closed-chain motion constraint relationship of the collaborative system; Among them, algorithm optimization is performed for dynamic trajectories, including real-time error feedback and model predictive control optimization; Real-time error feedback: Compare the measured data with the standard model and calculate the local margin deviation: ； When the average deviation of the region When trigger adjustment; Model predictive control optimization: Establish the robot kinematic model and grinding and polishing force model, and generate the optimal adjustment through rolling time domain optimization: ； Among them, y(k) is the actual trajectory, yref(k) is the reference trajectory, u(k) is the control input, and λ is the weight coefficient; Fault-tolerance mechanism: When the master robot's posture adjustment exceeds the limit, the slave robot is triggered to pause and wait for re-planning the path.

6. The trajectory control method of the dual robot grinding and polishing device based on master-slave dynamic adjustment according to claim 5 is characterized in that: In step S4, the main robot holding the workpiece moves according to a predetermined trajectory, and the slave robot performs constant force grinding according to the obtained trajectory. At the same time, the line laser measuring instrument measures the contour data of the workpiece surface in real time and transmits the contour data to the GUI interface. The GUI compares the transmitted contour data with the contour data of the standard model, adjusts the processing trajectory of the slave robot online in real time, and then outputs it to the slave robot controller to fine-tune the processing trajectory of the slave robot; when there is inconsistency with the expected model, the information is sent to the host computer in time, and the host computer controls the robot controller to make the dual robots stop urgently.

7. The trajectory control method of the dual robot grinding and polishing device based on master-slave dynamic adjustment according to claim 6 is characterized in that: In step S4, the main robot performs dynamic posture optimization in real time, and calculates the optimization direction of the main robot's clamping posture in real time based on the workpiece geometric model and the robot kinematic model: ； Among them, θ is the joint angle of the master robot, J(qi) is the Jacobian matrix condition number of the slave robot at the i-th path point, maximizing the overall motion flexibility; The slave robot coordinates motion control and establishes the kinematic constraint relationship between the master and slave robots: ； Among them, R1 and R2 represent the base coordinate systems of the master robot and the slave robot respectively, E1 and E2 represent the end coordinate systems of the two robots respectively, T1 and T2 represent the workpiece clamping tool coordinate system and the grinding tool coordinate system respectively, and w represents the workpiece coordinate system.

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