Grinding and polishing track self-adaptive adjustment method based on robot force and position mixed control

Abstract

The invention relates to the technical field of intelligent grinding and polishing of robots, and particularly discloses a grinding and polishing track self-adaptive adjustment method based on force and position mixed control of a robot, which comprises the following steps: acquiring a theoretical grinding and polishing track of the robot; compensating the theoretical grinding and polishing track of the robot to obtain a compensated grinding and polishing track of the robot; and controlling the robot to grind and polish the to-be-ground and polished workpiece according to the compensation grinding and polishing track of the robot. According to the grinding and polishing track self-adaptive adjustment method based on robot force and position mixed control, self-adaptive compensation and dynamic adjustment of the grinding and polishing track can be achieved, and therefore high precision, high stability and high reliability of the grinding and polishing process are guaranteed in a complex curved surface and high-precision grinding and polishing task.

Description

Technical Field

[0001] This invention relates to the field of robotic intelligent grinding and polishing technology, and more specifically, to a method for adaptive adjustment of grinding and polishing trajectory based on robot force-position hybrid control. Background Technology

[0002] In recent years, with the increasing demands from the manufacturing industry for adaptive grinding and polishing operations, surface grinding and polishing quality, and the ability to handle complex curved surfaces, robotic grinding and polishing technology has gradually become a research and application hotspot, showing a rapid development trend. Industrial robots, with their high repeatability, flexible programmability, and high degree of coordination with end effector devices, have become an important form of equipment for improving grinding and polishing efficiency, ensuring grinding and polishing quality, and reducing manual labor intensity. In the automotive, aerospace, and precision mold manufacturing industries, industrial robots, combined with force control devices and supporting intelligent grinding and polishing software, can achieve dynamic coupling control of force and posture during the grinding and polishing process, thereby stably and efficiently completing the grinding and polishing tasks of complex free-form surfaces.

[0003] In actual production, clamping and positioning errors inevitably occur during workpiece loading, clamping, and positioning, resulting in a difference between the actual workpiece pose and the theoretical pose set in the offline programming stage. If this pose error is not effectively compensated, when the robot directly performs grinding and polishing along the theoretical trajectory, the trajectory path deviates from the actual position of the workpiece, leading to the following problems: 1. Misalignment of polishing areas: The target polishing area cannot be properly covered, while non-polishing areas may be accidentally touched, resulting in residual material in some areas or over-cutting; 2. Increased surface defects: Scratches, over-grinding, under-grinding, and other defects occur, reducing surface quality; 3. Damaged morphological consistency: Increased precision differences between ground and polished parts affect the stability of mass production; 4. Severe rework or scrapping: In high-precision scenarios, this may directly render the parts unusable.

[0004] These problems not only affect the accuracy, stability, and robustness of the robot's polishing trajectory, but also lead to reduced production efficiency and increased manufacturing costs. Summary of the Invention

[0005] This invention aims to overcome the above-mentioned defects and provides an adaptive adjustment method for grinding and polishing trajectory based on robot force-position hybrid control. By integrating workpiece pose error detection with the flexible floating characteristics of the end force control device, a robot end force-position hybrid control mechanism is established to achieve adaptive compensation and dynamic adjustment of the grinding and polishing trajectory. This ensures high precision, high stability and high reliability of the grinding and polishing process in complex curved surfaces and high-precision grinding and polishing tasks.

[0006] As a first aspect of the present invention, a method for adaptive adjustment of grinding and polishing trajectory based on robot force-position hybrid control is provided, comprising the following steps: Step S1: Obtain the theoretical grinding and polishing trajectory of the robot; Step S2: Compensate the theoretical polishing trajectory of the robot to obtain the compensated polishing trajectory of the robot; Step S3: Control the robot to perform grinding and polishing on the workpiece to be ground and polished according to the robot's compensated grinding and polishing trajectory.

[0007] Further, step S1 includes: The theoretical grinding and polishing trajectory of the robot is generated based on the CAD model of the workpiece to be ground and polished and the preset target surface to be ground and polished; wherein, the theoretical grinding and polishing trajectory includes multiple theoretical grinding and polishing points, and each theoretical grinding and polishing point has coordinate information and attitude information.

[0008] Furthermore, steps S2 and S3 include: Calculate the compensation matrix based on the overall pose error of the workpiece to be ground and polished. The compensation matrix mentioned above Including rotation matrix Translation vector t; Calculate the floating stroke error of the force control device. ; According to the compensation matrix and the floating stroke error Each theoretical polishing point of the robot is compensated to obtain each compensated polishing point of the robot; the compensation formula is as follows: , , in, and These are the coordinate and attitude information for each theoretical polishing point. and These are the coordinate and attitude information for each compensation grinding and polishing point; The robot is controlled to perform grinding and polishing on the workpiece to be ground and polished based on each compensation grinding and polishing point of the robot.

[0009] Furthermore, the compensation matrix based on the overall pose error of the workpiece to be ground and polished is calculated. Including: After the workpiece to be ground and polished is loaded, the robot sequentially selects three actual points on the surface of the workpiece as the first calibration point, the second calibration point, and the third calibration point. Each selected calibration point is compared with its corresponding theoretical point to solve for the rotation matrix of the workpiece to be ground and polished relative to the theoretical model. The translation vector t is used to construct the compensation matrix. The compensation matrix Used to characterize the overall difference between the actual pose and the theoretical pose of the workpiece to be ground and polished.

[0010] Furthermore, the floating stroke error of the force control device is calculated. In addition, it also includes: During the grinding and polishing process of the robot on the workpiece to be polished, the actual floating stroke of the force control device is acquired in real time, and the difference between the actual floating stroke and the theoretical floating stroke is calculated and recorded as the floating stroke error. ; wherein, during the grinding and polishing process of the robot on the workpiece to be polished, the floating stroke error It is updated in real time.

[0011] Furthermore, the step of the robot sequentially selecting three actual points on the surface of the workpiece to be ground and polished as the first calibration point, the second calibration point, and the third calibration point after the workpiece is loaded includes: (1) After the workpiece to be ground and polished is loaded, a reference point on the workpiece to be ground and polished is selected according to the point selection principle and used as the first calibration point. The selection principle is as follows: the robot's end effector contacts the surface of the workpiece to be polished, and the contact is detected by the actual floating stroke or actual normal force of the force control device. When the contact is successful, the spatial coordinates of the robot's end effector in the base coordinate system are recorded as the first calibration point. ; (2) Select the workpiece to be ground and polished, excluding the first calibration point, according to the selection principle. Several candidate actual locations in addition to The actual locations of each candidate point are calculated using the following formula. Information content And select the candidate actual point with the most information as the second calibration point. : , In the formula, This is the first calibration point. For the i-th candidate actual point, for Direction vector and The angle between them It is a constant; (3) Select the workpiece to be ground and polished, excluding the first calibration point. Second calibration point Several candidate actual locations in addition to and several candidate actual locations Substitute each element into the following evaluation process; First, calculate the position of the first calibration point. Second calibration point and the j-th candidate actual point center of mass : , According to the center of mass Constructing a decentralized geometric matrix : , Then calculate the geometric matrix. The singular values, where the singular values ; The j-th candidate actual point location is calculated using the following formula. condition number And select condition numbers from them. The smallest candidate actual point is used as the third calibration point. : , In the formula, It is a constant.

[0012] Furthermore, the step of detecting whether contact was successful via the actual floating stroke or actual normal force of the force control device also includes: When the actual floating stroke of the force control device exceeds the preset stroke threshold or the actual normal force reaches the preset normal force threshold, successful contact is detected.

[0013] Furthermore, each selected calibration point is compared with its corresponding theoretical point to solve for the rotation matrix of the workpiece to be ground and polished relative to the theoretical model. The translation vector t is used to construct the compensation matrix. In addition, it also includes: (1) First, define the first calibration point. Second calibration point Third calibration point The corresponding theoretical points are as follows , , The centroids of the three calibration points were calculated respectively. Centroid of the three theoretical points : , in, For the k-th calibration point, This is the k-th theoretical point; (2) The centroid and the center of gravity All points are moved to the origin position, and the decentralized calibration point and the decentralized theoretical point are calculated respectively: , in, For the k-th decentralized calibration point, This represents the k-th decentralized theoretical node. (3) Decentralized calibration points Construct into a matrix The decentralized theoretical points Construct into a matrix Each column represents one point:

[0014] (4) Calculate the covariance matrix H: , (5) Perform singular value decomposition on the covariance matrix H: , in, , Describe the set of 3x3 orthogonal matrices. First, calculate the symmetric matrix. And perform feature decomposition on it: , in, These are the non-negative eigenvalues ​​arranged in descending order, and the corresponding eigenvectors are used to construct a matrix V; singular values Then matrix U is: , (6) Judgment Is it less than 0? like, definition Therefore, the rotation matrix is ​​obtained. ; like, Then the rotation matrix is ​​obtained directly. I is the identity matrix; (7) The translation vector t is: , (8) The compensation matrix for: .

[0015] Furthermore, it also includes: When the compensation matrix is ​​based on three calibration points If the requirements are not met, the number of calibration points is expanded, and the expanded set of points is defined. ,in, Let i be the i-th calibration point in set S. Let i be the theoretical point in set S; The weighted centroids are calculated using the weighted Kabsch algorithm. and And calculate the weighted covariance matrix H: , in, Let be the weight of the i-th calibration point; Similarly, singular value decomposition is performed on the weighted covariance matrix H to finally obtain the rotation matrix corresponding to the expanded point set S. Translate the vector t and construct a new compensation matrix. Used to compensate for theoretical grinding and polishing trajectories.

[0016] Furthermore, it also includes: To achieve adaptive selection and expansion of calibration points, the following parameter information matrix is ​​used: , in, It is the identity matrix; According to maximization Numerical adaptive selection of candidate actual points is used as expanded calibration points.

[0017] The adaptive adjustment method for grinding and polishing trajectory based on robot force-position hybrid control provided by this invention has the following beneficial effects: (1) Selecting three calibration points on the workpiece surface based on the principles of maximum information content and minimum condition number helps reduce the sensitivity of pose solution to point distribution and improves the numerical stability of the solution. Subsequently, the optimal matching relationship between the calibration points and theoretical points is solved by the singular value decomposition (SVD) algorithm, thereby constructing a compensation matrix that reflects the overall pose error of the workpiece. This compensation matrix can effectively correct the global trajectory error caused by workpiece clamping or positioning deviation; (2) During the execution of the robot, the local floating deviation fed back by the force control device can also be further corrected in real time to correct the attitude and position of the grinding and polishing point, thereby further suppressing the accumulation of minor errors and the influence of external disturbances during the grinding and polishing process. If the accuracy of the global compensation matrix is ​​still insufficient, the optimal new calibration point can be adaptively selected based on the parameter information matrix to expand the number of calibration points, thereby further improving the accuracy and reliability of the compensation matrix; (3) By organically combining global compensation based on geometric features with local compensation based on force control feedback, high-precision pose correction of grinding and polishing points can be achieved, thereby significantly improving the path tracking accuracy of the robot and the consistency of workpiece grinding and polishing under complex working conditions. Especially when there is a difference between the theoretical model of the workpiece and the actual clamping state, this method can effectively eliminate the deviation between the trajectory and the workpiece. Attached Figure Description

[0018] The accompanying drawings are provided to further illustrate the invention and form part of the specification. They are used together with the following detailed description to explain the invention, but do not constitute a limitation thereof.

[0019] Figure 1 The flowchart shows the adaptive adjustment method for grinding and polishing trajectory based on robot force-position mixing control provided by the present invention.

[0020] Figure 2 The flowchart illustrates a specific implementation of the adaptive adjustment method for grinding and polishing trajectories based on robot force-position mixing control provided by this invention.

[0021] Figure 3 The structural diagrams of the robot, force control device, and workpiece provided by this invention are shown. Detailed Implementation

[0022] To further illustrate the technical means and effects adopted by the present invention to achieve its intended purpose, the following, in conjunction with the accompanying drawings and preferred embodiments, details the specific implementation, structure, features, and effects of a grinding and polishing trajectory adaptive adjustment method based on robot force-position hybrid control proposed according to the present invention. Obviously, the described embodiments are only some, not all, of the embodiments of the present invention. All other embodiments obtained by those skilled in the art based on the embodiments of the present invention without creative effort are within the protection scope of the present invention.

[0023] It should be noted that the terms "first," "second," etc., in the specification, claims, and accompanying drawings of this invention are used to distinguish similar objects and are not necessarily used to describe a specific order or sequence. It should be understood that such data can be interchanged where appropriate for the embodiments of the invention described herein. Furthermore, the terms "comprising" and "having," and any variations thereof, are intended to cover a non-exclusive inclusion; for example, a process, method, system, product, or apparatus that comprises a series of steps or units is not necessarily limited to those steps or units explicitly listed, but may include other steps or units not explicitly listed or inherent to such processes, methods, products, or apparatus.

[0024] This embodiment provides a method for adaptive adjustment of grinding and polishing trajectories based on robot force-position hybrid control, wherein a force control device is configured at the end of the robot, such as... Figure 1 As shown, the adaptive adjustment method for grinding and polishing trajectory based on robot force-position hybrid control includes the following steps:

[0025] Step S1: Obtain the theoretical grinding and polishing trajectory of the robot; Preferably, step S1 includes: Using industrial robot offline programming software, a theoretical polishing trajectory for the robot is generated based on the CAD model of the workpiece to be polished and the preset target polishing surface. This theoretical trajectory includes multiple theoretical polishing points, each with three-dimensional spatial coordinates and attitude information, thus comprehensively describing the robot's motion requirements during the polishing process. This theoretical polishing trajectory serves as an initial trajectory template, providing fundamental data support for subsequent pose compensation and online fine-tuning.

[0026] Step S2: Compensate the theoretical polishing trajectory of the robot to obtain the compensated polishing trajectory of the robot; Step S3: Control the robot to perform grinding and polishing on the workpiece to be ground and polished according to the robot's compensated grinding and polishing trajectory.

[0027] Preferably, such as Figure 2 As shown, steps S2 and S3 include: Calculate the compensation matrix based on the overall pose error of the workpiece to be ground and polished. The compensation matrix mentioned above Including rotation matrix Translation vector t; Specifically, the calculation of the compensation matrix based on the overall pose error of the workpiece to be ground and polished... Including: After the workpiece to be ground and polished is loaded, the robot sequentially selects three actual points on the surface of the workpiece as the first calibration point, the second calibration point, and the third calibration point. More specifically, the step of the robot sequentially selecting three actual points on the surface of the workpiece to be ground and polished as the first calibration point, the second calibration point, and the third calibration point after the workpiece is loaded includes: (1) After the workpiece to be ground and polished is loaded, a reference point on the workpiece to be ground and polished is selected according to the point selection principle and used as the first calibration point. The selection principle is as follows: the robot's end effector contacts the surface of the workpiece to be polished, and the contact is detected by the actual floating stroke or actual normal force of the force control device. When the contact is successful, the spatial coordinates of the robot's end effector in the base coordinate system are recorded as the first calibration point. ; (2) To enhance the observability of pose estimation, the second calibration point is Should be aligned with the first calibration point Having the largest possible geometric difference; selecting the workpiece to be ground and polished, excluding the first calibration point, according to the aforementioned point selection principle. Several candidate actual locations in addition to The actual locations of each candidate point are calculated using the following formula. Information content And select the candidate actual point with the most information as the second calibration point. : , In the formula, This is the first calibration point. For the i-th candidate actual point, for Direction vector and The angle between them To prevent constants with a denominator of 0, this is set to 1; (3) Select the workpiece to be ground and polished, excluding the first calibration point. Second calibration point Several candidate actual locations in addition to and several candidate actual locations Substitute each element into the following evaluation process; First, calculate the position of the first calibration point. Second calibration point and the j-th candidate actual point center of mass : , According to the center of mass Constructing a decentralized geometric matrix : , Then calculate the geometric matrix. The singular values ​​of , where are obtained by finding the singular values. (Since the rank A ≤ 2 after decentralization of the three points, usually...) ≈0); To avoid degradation and ensure stability, the j-th candidate actual point location is calculated using the following formula. condition number And select condition numbers from them. The smallest candidate actual point is used as the third calibration point. : , In the formula, Let be a constant, and let it be... , condition number The smaller the value, the greater the difference in geometric distribution among the three calibration points, and the less sensitive it is to measurement noise.

[0028] Each selected calibration point is compared with its corresponding theoretical point (the theoretical point set during the offline programming stage) to solve for the rotation matrix of the workpiece to be ground and polished relative to the theoretical model. The translation vector t is used to construct the compensation matrix. The compensation matrix Used to characterize the overall difference between the actual pose and the theoretical pose of the workpiece to be ground and polished.

[0029] More specifically, each selected calibration point is compared with its corresponding theoretical point to solve for the rotation matrix of the workpiece to be ground and polished relative to the theoretical model. The translation vector t is used to construct the compensation matrix. In addition, it also includes: (1) First, define the first calibration point. Second calibration point Third calibration point The corresponding theoretical points are as follows , , The centroids of the three calibration points were calculated respectively. Centroid of the three theoretical points : , in, For the k-th calibration point, This is the k-th theoretical point; (2) The centroid and the center of gravity All points are moved to the origin position, and the decentralized calibration point and the decentralized theoretical point are calculated respectively: , in, For the k-th decentralized calibration point, This represents the k-th decentralized theoretical node. (3) Decentralized calibration points Construct into a matrix The decentralized theoretical points Construct into a matrix Each column represents one point: , (4) Calculate the covariance matrix H: , (5) Perform singular value decomposition on the covariance matrix H: , in, , Describe the set of 3x3 orthogonal matrices. First, calculate the symmetric matrix. And perform feature decomposition on it: , in, , are the non-negative eigenvalues ​​arranged in descending order, and the corresponding eigenvectors are used to construct a matrix V; singular values Then matrix U is: , (6) Judgment Is it less than 0? like To avoid reflection, define Therefore, the rotation matrix is ​​obtained. ; like Then the rotation matrix is ​​obtained directly. I is the identity matrix; That is, the rotation matrix R from the theoretical point to the actual point is calculated using the SVD method; (7) The translation vector t is: , (8) Therefore, a homogeneous compensation matrix from the theoretical point to the actual point is constructed. for: .

[0030] Finally, all theoretical grinding and polishing points of the robot are constructed as follows: The column vector format is then multiplied on the left by the compensation matrix calculated above. This allows us to obtain the compensated grinding and polishing points based on workpiece pose offset compensation. .

[0031] Calculate the floating stroke error of the force control device. ; Specifically, the floating stroke error of the force control device is calculated. In addition, it also includes: During the grinding and polishing process of the robot on the workpiece to be polished, the actual floating stroke of the force control device is acquired in real time, and the difference between the actual floating stroke and the theoretical floating stroke is calculated and recorded as the floating stroke error. According to the floating stroke error The spatial attitude and position of the polishing trajectory are adaptively adjusted; wherein, during the polishing process of the robot on the workpiece to be polished, the floating stroke error... It is updated in real time.

[0032] According to the compensation matrix and the floating stroke error Each theoretical polishing point of the robot is compensated to obtain each compensated polishing point of the robot; the compensation formula is as follows: , in, and These are the coordinate and attitude information for each theoretical polishing point. and These are the coordinate and attitude information for each compensation grinding and polishing point; The robot is controlled to perform grinding and polishing on the workpiece to be ground and polished based on each compensation grinding and polishing point of the robot.

[0033] Preferably, such as Figure 2 As shown, it also includes: When the actual pose of the workpiece deviates significantly from its theoretical pose, in order to ensure the stability and usability of the obtained compensation matrix, the compensation matrix based on the three calibration points... If the requirements are not met, the number of calibration points is expanded to add calibration points for adaptive calibration, and the expanded set of points is defined. ,in, Let i be the i-th calibration point in set S. Let i be the theoretical point in set S; The weighted centroids are calculated using the weighted Kabsch algorithm. and And calculate the weighted covariance matrix H: , in, Let be the weight of the i-th calibration point; Similarly, singular value decomposition is performed on the weighted covariance matrix H to finally obtain the rotation matrix corresponding to the expanded point set S. Translate the vector t and construct a new compensation matrix. Used to compensate for theoretical grinding and polishing trajectories.

[0034] Specifically, it also includes: To achieve adaptive selection and expansion of calibration points, the following parameter information matrix is ​​used: , in, It is the identity matrix; According to maximization Numerical adaptive selection of candidate actual points is used as expanded calibration points.

[0035] It should be noted that, as Figure 3 As shown, the process of detecting whether contact is successful by the actual floating stroke or actual normal force of the force control device also includes: The end effector of robot 1 is equipped with a force control device 2 to achieve wide-range flexible compliance, used for large-stroke flexible compliance and reliable contact detection during the approach phase to workpiece 3. The force control device 2 provides relative displacement tolerance within a preset range through a compliant mechanism to absorb clamping and positioning deviations of workpiece 3 and achieve safe docking; the floating stroke can reach tens of millimeters. When the actual floating stroke of the force control device 2 exceeds a preset stroke threshold or the actual normal force reaches a preset normal force threshold, successful contact is detected and the contact point coordinates are recorded.

[0036] In this embodiment of the invention, (1) after the workpiece is loaded, the industrial robot sequentially selects calibration points for pose estimation on the workpiece surface. Specifically, the spatial coordinates of the first calibration point are first collected and recorded; then, several candidate points are generated on the workpiece surface, and the remaining calibration points are determined from the candidate points based on the criteria of maximizing information and minimizing condition number, preferably at least three non-collinear points with good spatial distribution. (2) The selected calibration points are matched and compared with their corresponding theoretical points to solve the translation and rotation deviation parameters of the workpiece relative to the theoretical model. On this basis, a homogeneous compensation matrix is ​​constructed to characterize the overall difference between the theoretical pose and the actual pose of the workpiece. By applying the compensation matrix to all the original theoretical grinding and polishing points of the industrial robot, the corrected compensation grinding and polishing trajectory can be generated. (3) Based on this trajectory, the local floating stroke error fed back by the force control device is combined to perform secondary compensation on the robot grinding and polishing trajectory, including a small correction of the coordinates of the grinding and polishing points, so as to suppress the minor deviations caused by contact stiffness fluctuations, clamping errors and external disturbances during the grinding and polishing process. If the compensation effect of the initially constructed compensation matrix is ​​still not ideal, more calibration points can be added based on the parameter information matrix to improve the accuracy and reliability of the compensation matrix. (4) Through the synergy of the above global geometric compensation and local force-position hybrid fine adjustment, the trajectory adaptive adjustment without re-teaching is realized, so that the robot maintains a high consistency with the actual position of the workpiece in the complex surface grinding and polishing operation.

[0037] The present invention proposes a method for adaptive adjustment of grinding and polishing trajectory based on robot force-position hybrid control. This method is applicable to workpiece pose error compensation and adaptive adjustment of grinding and polishing trajectory under the condition of clamping and positioning errors, so as to improve the grinding and polishing quality and consistency of complex curved surfaces.

[0038] This invention proposes an adaptive adjustment method for grinding and polishing trajectory based on robot force-position hybrid control. (1) Three calibration points are selected on the workpiece surface based on the principles of maximum information content and minimum condition number, which helps to reduce the sensitivity of pose solution to point distribution and improve the numerical stability of the solution. Subsequently, the optimal matching relationship between the calibration points and theoretical points is solved by the singular value decomposition (SVD) algorithm, thereby constructing a compensation matrix that reflects the overall pose error of the workpiece. This compensation matrix can effectively correct the global trajectory error caused by workpiece clamping or positioning deviation; (2) During the execution of the robot, the local floating deviation fed back by the force control device can also be further corrected to the posture and position of the grinding and polishing points through real-time compensation, further suppressing the accumulation of subtle errors and the influence of external disturbances during the grinding and polishing process. If the accuracy of the global compensation matrix is ​​still insufficient, the optimal new calibration point can be adaptively selected based on the parameter information matrix to expand the number of calibration points, thereby further improving the accuracy and reliability of the compensation matrix; (3) By organically combining global compensation based on geometric features with local compensation based on force control feedback, high-precision pose correction of the grinding and polishing points can be achieved, thereby significantly improving the path tracking accuracy of the robot and the consistency of workpiece grinding and polishing under complex working conditions. Especially when there is a difference between the theoretical model of the workpiece and the actual clamping state, this method can effectively eliminate the deviation between the trajectory and the workpiece.

[0039] The above description is merely a preferred embodiment of the present invention and is not intended to limit the present invention in any way. Although the present invention has been disclosed above with reference to preferred embodiments, it is not intended to limit the present invention. Any person skilled in the art can make some modifications or alterations to the above-disclosed technical content to create equivalent embodiments without departing from the scope of the present invention. Any simple modifications, equivalent changes, and alterations made to the above embodiments based on the technical essence of the present invention without departing from the scope of the present invention shall still fall within the scope of the present invention.

Claims

1. A method for adaptive adjustment of grinding and polishing trajectory based on robot force-position hybrid control, wherein a force control device is configured at the end of the robot, characterized in that, The adaptive adjustment method for grinding and polishing trajectory based on robot force-position hybrid control includes the following steps: Step S1: Obtain the theoretical grinding and polishing trajectory of the robot; Step S2: Compensate the theoretical polishing trajectory of the robot to obtain the compensated polishing trajectory of the robot; Step S3: Control the robot to perform grinding and polishing on the workpiece to be ground and polished according to the robot's compensated grinding and polishing trajectory.

2. The method for adaptive adjustment of grinding and polishing trajectory based on robot force-position hybrid control according to claim 1, characterized in that, Step S1 includes: The theoretical grinding and polishing trajectory of the robot is generated based on the CAD model of the workpiece to be ground and polished and the preset target surface to be ground and polished; wherein, the theoretical grinding and polishing trajectory includes multiple theoretical grinding and polishing points, and each theoretical grinding and polishing point has coordinate information and attitude information.

3. The method for adaptive adjustment of grinding and polishing trajectory based on robot force-position hybrid control according to claim 2, characterized in that, Steps S2 and S3 include: Calculate the compensation matrix based on the overall pose error of the workpiece to be ground and polished. The compensation matrix mentioned above Including rotation matrix Translation vector t; Calculate the floating stroke error of the force control device. ; According to the compensation matrix and the floating stroke error Each theoretical polishing point of the robot is compensated to obtain each compensated polishing point of the robot; the compensation formula is as follows: ， ， in, and These are the coordinate and attitude information for each theoretical polishing point. and These are the coordinate and attitude information for each compensation grinding and polishing point; The robot is controlled to perform grinding and polishing on the workpiece to be ground and polished based on each compensation grinding and polishing point of the robot.

4. The method for adaptive adjustment of grinding and polishing trajectory based on robot force-position hybrid control according to claim 3, characterized in that, The compensation matrix calculated based on the overall pose error of the workpiece to be ground and polished is then determined. Including: After the workpiece to be ground and polished is loaded, the robot sequentially selects three actual points on the surface of the workpiece as the first calibration point, the second calibration point, and the third calibration point. Each selected calibration point is compared with its corresponding theoretical point to solve for the rotation matrix of the workpiece to be ground and polished relative to the theoretical model. The translation vector t is used to construct the compensation matrix. The compensation matrix Used to characterize the overall difference between the actual pose and the theoretical pose of the workpiece to be ground and polished.

5. The method for adaptive adjustment of grinding and polishing trajectory based on robot force-position hybrid control according to claim 3, characterized in that, The floating stroke error of the force control device is calculated. In addition, it also includes: During the grinding and polishing process of the robot on the workpiece to be polished, the actual floating stroke of the force control device is acquired in real time, and the difference between the actual floating stroke and the theoretical floating stroke is calculated and recorded as the floating stroke error. ; wherein, during the grinding and polishing process of the robot on the workpiece to be polished, the floating stroke error It is updated in real time.

6. The method for adaptive adjustment of grinding and polishing trajectory based on robot force-position hybrid control according to claim 4, characterized in that, The process of the robot sequentially selecting three actual points on the surface of the workpiece after loading is completed, as the first calibration point, the second calibration point, and the third calibration point, further includes: (1) After the workpiece to be ground and polished is loaded, a reference point on the workpiece to be ground and polished is selected according to the point selection principle and used as the first calibration point. The selection principle is as follows: the robot's end effector contacts the surface of the workpiece to be polished, and the contact is detected by the actual floating stroke or actual normal force of the force control device. When the contact is successful, the spatial coordinates of the robot's end effector in the base coordinate system are recorded as the first calibration point. ; (2) Select the workpiece to be ground and polished, excluding the first calibration point, according to the selection principle. Several candidate actual locations in addition to The actual locations of each candidate point are calculated using the following formula. Information content And select the candidate actual point with the most information as the second calibration point. : ， In the formula, This is the first calibration point. For the i-th candidate actual point, for Direction vector and The angle between them It is a constant; (3) Select the workpiece to be ground and polished, excluding the first calibration point. Second calibration point Several candidate actual locations in addition to and several candidate actual locations Substitute each element into the following evaluation process; First, calculate the position of the first calibration point. Second calibration point and the j-th candidate actual point center of mass : ， According to the center of mass Constructing a decentralized geometric matrix : ， Then calculate the geometric matrix. The singular values, where the singular values ; The j-th candidate actual point location is calculated using the following formula. condition number And select condition numbers from them. The smallest candidate actual point is used as the third calibration point. : ， In the formula, It is a constant.

7. The method for adaptive adjustment of grinding and polishing trajectory based on robot force-position hybrid control according to claim 6, characterized in that, The process of detecting whether contact was successful by means of the actual floating stroke or actual normal force of the force control device also includes: When the actual floating stroke of the force control device exceeds the preset stroke threshold or the actual normal force reaches the preset normal force threshold, successful contact is detected.

8. The method for adaptive adjustment of grinding and polishing trajectory based on robot force-position hybrid control according to claim 6, characterized in that, The process involves comparing each selected calibration point with its corresponding theoretical point to calculate the rotation matrix of the workpiece to be ground and polished relative to the theoretical model. The translation vector t is used to construct the compensation matrix. In addition, it also includes: (1) First, define the first calibration point. Second calibration point Third calibration point The corresponding theoretical points are as follows , , The centroids of the three calibration points were calculated respectively. Centroids of the three theoretical points : ， ， in, For the k-th calibration point, This is the k-th theoretical point; (2) The centroid and the center of the circle All points are moved to the origin position, and the decentralized calibration point and the decentralized theoretical point are calculated respectively: ， ， in, For the k-th decentralized calibration point, This represents the k-th decentralized theoretical node. (3) Decentralized calibration points Construct into a matrix The decentralized theoretical points Construct into a matrix Each column represents one point: ， ， (4) Calculate the covariance matrix H: ， (5) Perform singular value decomposition on the covariance matrix H: ， in, , Describe the set of 3x3 orthogonal matrices. First, calculate the symmetric matrix. And perform feature decomposition on it: ， in, , are the non-negative eigenvalues ​​arranged in descending order, and the corresponding eigenvectors are used to construct a matrix V; singular values Then matrix U is: ， (6) Judgment Is it less than 0? like ,definition Therefore, the rotation matrix is ​​obtained. ; like Then the rotation matrix is ​​obtained directly. I is the identity matrix; (7) The translation vector t is: ， (8) The compensation matrix for: 。 9. The method for adaptive adjustment of grinding and polishing trajectory based on robot force-position hybrid control according to claim 4, characterized in that, Also includes: When the compensation matrix is ​​based on three calibration points If the requirements are not met, the number of calibration points is expanded, and the expanded set of points is defined. ,in, Let i be the i-th calibration point in set S. Let i be the i-th theoretical point in set S; The weighted centroids are calculated using the weighted Kabsch algorithm. and And calculate the weighted covariance matrix H: ， in, Let be the weight of the i-th calibration point; Similarly, singular value decomposition is performed on the weighted covariance matrix H to finally obtain the rotation matrix corresponding to the expanded point set S. Translate the vector t and construct a new compensation matrix. Used to compensate for theoretical grinding and polishing trajectories.

10. The method for adaptive adjustment of grinding and polishing trajectory based on robot force-position hybrid control according to claim 9, characterized in that, Also includes: To achieve adaptive selection and expansion of calibration points, the following parameter information matrix is ​​used: ， in, It is the identity matrix; According to maximization Numerical adaptive selection of candidate actual points is used as expanded calibration points.

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