A robotic constant force polishing method, system, device, and storage medium

Abstract

The application provides a robot constant force polishing method, system, device and storage medium, the method comprises the following steps: obtaining joint space constraints and dynamics model to execute force control step; the step: obtaining joint configuration, external force information and end position, obtaining end position Jacobian according to the configuration and position, obtaining contact identification according to the external force information and configuration, if the identification is contact, obtaining constraint and motion Jacobian based on the end position, space constraints and end position Jacobian; obtaining motion subspace control force according to the end position; obtaining constraint direction equivalent inertia based on the constraint Jacobian and dynamics model, obtaining coupled prediction error based on the constraint, motion Jacobian, control force, dynamics model and configuration, obtaining final joint torque control polishing based on inertia, motion and constraint Jacobian; obtaining feedback information to modify joint space constraints and execute force control step until polishing is completed. The application can improve the contact force accuracy between the end of the robot polishing process and the surface of the target workpiece.

Description

Technical Field

[0001] This invention relates to the field of robotic polishing technology, and in particular to a robotic constant force polishing method, system, equipment, and storage medium. Background Technology

[0002] In the process of a robot grinding a workpiece, it is necessary to maintain a constant contact force while moving rapidly along the surface of the target workpiece to ensure uniform grinding. Traditional grinding solutions use force feedback to correct the contact force during movement to ensure constant pressure. However, in high-speed grinding scenarios, the force feedback of traditional solutions is delayed due to high-speed movement, which increases and accumulates force error. This prevents the robot's end effector from maintaining a stable and continuous contact with the workpiece, resulting in uneven grinding.

[0003] To address the aforementioned issues, existing technologies achieve constant-force grinding control during robotic grinding based on real-time force feedback. Specifically, this involves acquiring data from force sensors in real-time, compensating for gravity to obtain the actual grinding contact force, and employing an impedance control algorithm under unknown environmental stiffness. This algorithm calculates the corresponding position adjustment based on the real-time contact force and the desired contact force during grinding. This position adjustment is then added to the robot's grinding trajectory to achieve constant-force grinding control. However, during high-speed grinding, the shapes of the abrasive and the workpiece decrease with each grinding cycle. Changes in the workpiece surface curvature introduce additional force interference to the contact force direction. The impedance control method in existing technologies does not effectively compensate for this interference. Consequently, the deviation between the actual contact force and the desired constant force gradually increases during high-speed grinding, reducing the accuracy of the contact force between the robot's end-point grinding process and the target workpiece surface. Summary of the Invention

[0004] The present invention aims to provide a robot constant force grinding method, system and equipment to solve the above-mentioned technical problems and improve the contact force accuracy between the end of the robot grinding process and the surface of the target workpiece.

[0005] To address the aforementioned technical problems, this invention provides a robotic constant-force grinding method, comprising the following steps: Obtain the joint space constraints on the surface of the target workpiece and obtain the dynamic model of the robot; The grinding result is obtained by executing force control steps based on the dynamic model and the joint space constraints. The force control steps include: Obtain the current joint configuration, current external force information, and current end effector position, and generate the end effector position Jacobian based on the current joint configuration and current end effector position; Based on the current external force information, the current joint configuration, and the Jacobian of the end position, the estimated end external force is obtained, and the estimated end external force is compared with a preset contact determination threshold to obtain a contact identifier; If the contact identifier is confirmed as contact, then the constraint Jacobian and motion Jacobian are obtained based on the current end position, the joint space constraint, and the end position Jacobian. Under the preset desired end trajectory, a motion subspace control force is generated based on the current end position; The constraint direction equivalent inertia is obtained based on the constraint Jacobian and the dynamic model, and the coupling prediction bias is generated based on the constraint direction equivalent inertia, the constraint Jacobian, the motion Jacobian, the motion subspace control force, the dynamic model and the current joint configuration. The final joint torque is obtained based on the coupling prediction deviation, the equivalent inertia of the constraint direction, the motion Jacobian, and the constraint Jacobian, and the robot is controlled to grind the target workpiece based on the final joint torque. If the grinding operation status is not obtained and it is confirmed that the grinding operation status is not grinding complete, feedback information is obtained, and the joint space constraint is corrected based on the feedback information. The force control step is re-executed using the corrected joint space constraint as the joint space constraint until the grinding operation status is grinding complete, and the grinding result is obtained.

[0006] The above scheme generates an end-effector position Jacobian based on the current joint configuration and end-effector position. This Jacobian is then combined with the current external force information and joint configuration to obtain an estimated end-effector force matching the current robot state. A contact indicator is then obtained based on this estimated end-effector force. If the contact indicator indicates contact, it signifies that the robot end-effector has made contact with the target workpiece surface. At this point, based on the current end-effector position, joint space constraints, and the end-effector position Jacobian, a constraint Jacobian corresponding to the contact force direction to be controlled (normal direction to the target workpiece surface) and a motion Jacobian corresponding to the tangential motion direction to the target workpiece surface are obtained. Finally, a motion subspace control force is generated based on the desired end-effector trajectory and the current end-effector position. This solution obtains the equivalent inertia of the constraint direction based on the aforementioned constraint Jacobian and dynamic model. Then, using the equivalent inertia of the constraint direction, constraint Jacobian, motion Jacobian, motion subspace control force, dynamic model, and current joint configuration, it generates a coupling prediction deviation that can adapt to the current robot grinding condition. The final joint torque grinding obtained based on this coupling prediction deviation, the equivalent inertia of the constraint direction, the motion Jacobian, and the constraint Jacobian can effectively compensate for the real-time contact force deviation caused by the change in the shape of the target workpiece during the robot grinding process. Furthermore, it continuously corrects the joint space constraints based on feedback signals, enabling the robot end effector to maintain a stable contact with the surface of the target workpiece during the overall grinding process, thereby improving the contact force accuracy between the robot end effector and the surface of the target workpiece during the grinding process.

[0007] Furthermore, the step of obtaining the joint space constraints of the target workpiece surface and obtaining the robot's dynamic model includes: obtaining the contact point set of the target workpiece surface and fitting a fitted surface based on the contact point set; obtaining the joint space constraints based on the fitted surface; obtaining the robot's inertia term, Coriolis term, and gravity term, and obtaining the dynamic model based on the inertia term, the Coriolis term, and the gravity term.

[0008] The above scheme first obtains the set of contact points on the surface of the target workpiece. Based on this set of contact points, a fitted surface reflecting the geometry of the workpiece surface is obtained. Then, the joint space constraint that conforms to the surface shape of the target workpiece is obtained through the fitted surface, reducing the grinding contact force deviation caused by joint space constraint errors, thereby improving the contact force accuracy between the end effector and the workpiece surface during the overall grinding process. This scheme obtains a dynamic model based on the robot's inertia, Coriolis, and gravity terms, so that the subsequent generated coupling prediction deviation can reflect the interference of inertial force, Coriolis force, etc. on the contact force. This allows the robot to predict and compensate for the interference caused by the grinding operation motion when grinding at high speed based on the compensated final joint torque, ensuring that the end effector conforms to the workpiece surface and improving the contact force accuracy between the end effector and the target workpiece surface during the robot grinding process.

[0009] Further, in the step of acquiring the grinding operation status and confirming that the grinding operation status is not grinding complete, then acquiring feedback information, obtaining corrected joint space constraints based on the feedback information, and re-executing the force control steps using the corrected joint space constraints as joint space constraints until the grinding operation status is grinding complete and the grinding result is obtained, the step of acquiring feedback information, obtaining corrected joint space constraints based on the feedback information, and re-executing the force control steps using the corrected joint space constraints as joint space constraints includes: acquiring feedback information from the robot, and acquiring a force tracking error sequence, a grinding trajectory position sequence, and an estimated environmental stiffness from the feedback information; obtaining an average force error based on the force tracking error sequence and the grinding trajectory sequence, and acquiring a normal displacement deviation based on the average force error and the estimated environmental stiffness; compensating the fitted surface based on the normal displacement deviation to generate a corrected surface, and obtaining corrected joint space constraints based on the corrected surface; using the corrected joint space constraints as joint space constraints, and re-executing the force control steps based on the joint space constraints.

[0010] The above scheme obtains feedback information to extract the force tracking error sequence, the grinding trajectory position sequence, and the estimated environmental stiffness. The force tracking error sequence reflects the change of the error between the actual contact force and the expected force during the grinding process with grinding time. The grinding trajectory position sequence corresponds to the force tracking error sequence and can reflect the location of each error. The estimated environmental stiffness reflects the resistance of the contact surface between the robot and the workpiece to deformation under external forces. Subsequently, this scheme obtains the average force error based on the force tracking error sequence and the grinding trajectory sequence, and obtains the normal displacement deviation based on the average force error and the estimated environmental stiffness. Then, based on the normal displacement deviation, the fitted surface is compensated to generate a corrected surface, making the corrected surface more closely fit the actual geometry of the workpiece. Based on the corrected surface, the corrected joint space constraint is obtained, and the corrected joint space constraint is used as the joint space constraint for the next force control step. This makes the coupling prediction deviation obtained in the next force control step more accurate, reduces the contact force deviation caused by the continuous wear and tear of the workpiece and the change of surface shape during continuous grinding, and improves the contact force accuracy between the robot end effector and the workpiece surface.

[0011] Furthermore, it also includes: confirming that the contact identifier is not in contact, then obtaining motion control equivalent effect based on the current end position under the preset desired end trajectory; extracting the robot gravity term from the dynamic model according to the current joint configuration, and obtaining the joint torque based on the robot gravity term, the motion control equivalent effect, and the Jacobian of the end position; controlling the robot action based on the joint torque to obtain the robot control state; confirming that the robot control state is control completed, then re-executing the force control step.

[0012] When the contact marker is not in contact, the above scheme obtains motion control and other effects based on the current end position under the preset desired end trajectory. According to the current joint configuration, the robot gravity term is extracted from the dynamic model. Based on the gravity term, motion control and other effects, and the Jacobian of the end position, a joint torque that can offset the influence of the robot's own gravity on its motion is obtained. Based on the joint torque, the robot's movement is controlled, which can reduce the situation where the robot end falls or deviates due to gravity. When the end is not in contact with the workpiece surface, the robot can smoothly approach the workpiece surface until the end makes contact with the workpiece surface, so that the grinding can start stably after contact. In the initial grinding, the robot end can stably fit with the target workpiece surface, thereby improving the contact force accuracy between the end and the workpiece surface during the overall grinding operation.

[0013] Further, the step of confirming that the contact identifier is a contact, and then obtaining the constraint Jacobian and motion Jacobian based on the current end position, the joint space constraint, and the end position Jacobian, includes: confirming that the contact identifier is a contact, then obtaining the surface gradient based on the current end position and the joint space constraint; generating the constraint Jacobian based on the surface gradient and the end position Jacobian, and obtaining the current normal direction based on the surface gradient; and generating the motion Jacobian based on the current normal unit direction.

[0014] Further, the step of obtaining the constraint direction equivalent inertia based on the constraint Jacobian and the dynamic model, and generating a coupling prediction deviation based on the constraint direction equivalent inertia, the constraint Jacobian, the motion Jacobian, the motion subspace control force, the dynamic model, and the current joint configuration includes: extracting robot inertia terms and robot Coriolis terms from the dynamic model; obtaining the constraint direction equivalent inertia based on the constraint Jacobian and the robot inertia terms; obtaining inertial coupling compensation based on the constraint direction equivalent inertia, the constraint Jacobian, the motion Jacobian, the robot inertia terms, and the motion subspace control force; obtaining velocity coupling compensation based on the current joint configuration, the constraint direction equivalent inertia, the robot Coriolis term, the robot inertia terms, and the constraint Jacobian; and generating a coupling prediction deviation based on the inertial coupling compensation and the velocity coupling compensation.

[0015] The aforementioned scheme derives the equivalent inertia in the constraint direction based on the constraint Jacobian and the robot's inertial term. Inertial coupling compensation is then obtained based on the equivalent inertia in the constraint direction, constraint Jacobian, motion Jacobian, robot inertial term, and motion subspace control force to offset the interference force generated by the robot's inertial force in the normal direction of the workpiece surface during tangential acceleration. Furthermore, velocity coupling compensation is obtained based on the current joint configuration, equivalent inertia in the constraint direction, robot Coriolis term, robot inertial term, and constraint Jacobian to offset the dynamic deviation caused by velocity during high-speed grinding. Subsequently, this scheme generates a coupling prediction deviation based on inertial coupling compensation and velocity coupling compensation to compensate for the interference force caused by tangential acceleration and velocity. This ensures that even with drastic changes in joint surface curvature during high-speed grinding along the workpiece surface, the actual contact force at the end effector closely follows the desired force, ensuring stable contact between the robot's end effector and the target workpiece surface, and improving the contact force accuracy between the end effector and the workpiece surface throughout the overall grinding process.

[0016] Further, the step of obtaining the final joint torque based on the coupling prediction deviation, the equivalent inertia of the constraint direction, the motion Jacobian, and the constraint Jacobian, and controlling the robot to grind the target workpiece based on the final joint torque, includes: obtaining a normal control force based on the coupling prediction deviation under a preset desired normal contact force; extracting the robot gravity term from the dynamic model based on the current joint configuration; obtaining the final joint torque based on the normal control force, the motion subspace control force, the motion Jacobian, and the constraint Jacobian; and controlling the robot to grind the target workpiece based on the final joint torque.

[0017] The above scheme is based on the normal control force obtained under the preset expected normal contact force by the coupling prediction deviation. This normal control force can offset the coupling deviation predicted by the coupling prediction deviation, and can make the actual contact force in the constraint direction during subsequent robot grinding approach the expected value. After obtaining the normal control force, the final joint torque is obtained according to the normal control force, motion subspace control force, motion Jacobian and constraint Jacobian, so that the obtained final joint torque fits the actual robot grinding conditions, and makes the robot end effector fit tightly with the surface of the target workpiece, thereby improving the contact force accuracy between the end effector and the workpiece surface during the overall grinding operation.

[0018] This invention also provides a robot constant force grinding system for implementing a robot constant force grinding method as described in any of the preceding claims, comprising: a joint space constraint and dynamic model acquisition module for acquiring joint space constraints on the surface of a target workpiece and acquiring a dynamic model of the robot; a force-controlled grinding module for executing force control steps based on the dynamic model and the joint space constraints to obtain a grinding result; the force control steps include: acquiring the current joint configuration, current external force information, and current end effector position, and generating an end effector position Jacobian based on the current joint configuration and current end effector position; acquiring an estimated end effector external force based on the current external force information, current joint configuration, and the end effector position Jacobian, and comparing the estimated end effector external force with a preset contact determination threshold to obtain a contact identifier; confirming that the contact identifier is a contact, then obtaining a constraint Jacobian and motion based on the current end effector position, the joint space constraints, and the end effector position Jacobian. Jacobi; Under the preset desired end-effector trajectory, a motion subspace control force is generated based on the current end-effector position; Based on the constraint Jacobi and the dynamic model, the constraint direction equivalent inertia is obtained, and based on the constraint direction equivalent inertia, the constraint Jacobi, the motion Jacobi, the motion subspace control force, the dynamic model, and the current joint configuration, a coupling prediction deviation is generated; Based on the coupling prediction deviation, the constraint direction equivalent inertia, the motion Jacobi, and the constraint Jacobi, the final joint torque is obtained, and based on the final joint torque, the robot is controlled to grind the target workpiece; The grinding operation status is obtained, and if it is confirmed that the grinding operation status is not grinding complete, feedback information is obtained, and the corrected joint space constraint is obtained based on the feedback information. The corrected joint space constraint is used as the joint space constraint to re-execute the force control steps until the grinding operation status is grinding complete, and the grinding result is obtained.

[0019] The present invention also provides a terminal device, including a processor, a memory, and a computer program stored in the memory and configured to be executed by the processor, wherein when the processor executes the computer program, it implements a robotic constant force grinding method as described in any of the preceding claims.

[0020] The present invention also provides a computer-readable storage medium, comprising: a stored computer program, wherein, when the computer program is executed, it controls the device on which the computer-readable storage medium is located to perform a robotic constant-force grinding method as described in any of the preceding claims.

[0021] The above scheme generates an end-effector position Jacobian based on the current joint configuration and end-effector position. This Jacobian is then combined with the current external force information and joint configuration to obtain an estimated end-effector force matching the current robot state. A contact identifier is then obtained based on this estimated end-effector force. If the contact identifier indicates contact, then based on the current end-effector position, joint space constraints, and the end-effector position Jacobian, a constraint Jacobian corresponding to the contact force direction to be controlled (normal direction of the target workpiece surface) and a motion Jacobian corresponding to the tangential motion direction of the target workpiece surface are obtained. Subsequently, this scheme obtains the equivalent inertia of the constraint direction based on the aforementioned constraint Jacobian and dynamic model. Then, using the equivalent inertia of the constraint direction, constraint Jacobian, motion Jacobian, motion subspace control force, dynamic model, and current joint configuration, it generates a coupling prediction deviation that can adapt to the current robot grinding condition. The final joint torque grinding obtained based on this coupling prediction deviation, the equivalent inertia of the constraint direction, the motion Jacobian, and the constraint Jacobian can effectively compensate for the real-time contact force deviation caused by the change in the shape of the target workpiece during continuous grinding. Furthermore, based on the feedback signal, it continuously corrects the joint space constraint, enabling the robot end effector to maintain a stable contact with the surface of the target workpiece during the overall grinding process, thereby improving the contact force accuracy between the robot end effector and the surface of the target workpiece during the grinding process. Attached Figure Description

[0022] To more clearly illustrate the technical solution of this application, the drawings used in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this application. For those skilled in the art, other drawings can be obtained from these drawings without creative effort.

[0023] Figure 1 This is a flowchart illustrating the technical implementation of a robot constant force grinding method according to an embodiment of the present invention; Figure 2 This is a flowchart illustrating the force control steps of a robot constant force grinding method according to an embodiment of the present invention. Detailed Implementation

[0024] To make the objectives, technical solutions, and advantages of this application clearer, the technical solutions of this application will be clearly and completely described below with reference to the accompanying drawings of the embodiments. Obviously, the described embodiments are only some embodiments of this application, not all embodiments. Based on the embodiments of this application, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this application.

[0025] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this application pertains; the terminology used herein is for the purpose of describing particular embodiments only and is not intended to limit the application; the terms “comprising” and “having”, and any variations thereof, in the specification, claims, and foregoing description of the drawings are intended to cover non-exclusive inclusion.

[0026] In the description of the embodiments of this application, technical terms such as "first" and "second" are used only to distinguish different objects and should not be construed as indicating or implying relative importance or implicitly specifying the number, specific order, or primary and secondary relationship of the indicated technical features. In the description of the embodiments of this application, "multiple" means two or more, unless otherwise explicitly defined.

[0027] In this document, the term "embodiment" means that a particular feature, structure, or characteristic described in connection with an embodiment may be included in at least one embodiment of this application. The appearance of this phrase in various places throughout the specification does not necessarily refer to the same embodiment, nor is it a separate or alternative embodiment mutually exclusive with other embodiments. It will be explicitly and implicitly understood by those skilled in the art that the embodiments described herein can be combined with other embodiments.

[0028] In the description of the embodiments in this application, the term "and / or" is merely a description of the relationship between related objects, indicating that three relationships can exist. For example, A and / or B can represent: A existing alone, A and B existing simultaneously, and B existing alone. Additionally, the character " / " in this document generally indicates that the preceding and following related objects have an "or" relationship.

[0029] In the description of the embodiments of this application, the term "multiple" refers to two or more (including two), similarly, "multiple sets" refers to two or more (including two sets), and "multiple pieces" refers to two or more (including two pieces).

[0030] In the description of the embodiments of this application, unless otherwise expressly specified and limited, technical terms such as "installation," "connection," "joining," and "fixing" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral part; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal communication of two components or the interaction between two components. For those skilled in the art, the specific meaning of the above terms in the embodiments of this application can be understood according to the specific circumstances.

[0031] Please see Figure 1 This embodiment provides a robot constant force grinding method, including the following steps: Step S1: Obtain the joint space constraints on the surface of the target workpiece and obtain the dynamic model of the robot; Step S2: Based on the dynamic model and the joint space constraints, perform force control steps to obtain the grinding result; Please see Figure 2 The force control steps include: Step S201: Obtain the current joint configuration, current external force information, and current end-effector position, and generate the end-effector position Jacobian based on the current joint configuration and current end-effector position; Step S202: Based on the current external force information, the current joint configuration, and the Jacobian of the end position, obtain the estimated end external force, and compare the estimated end external force with the preset contact determination threshold to obtain the contact identifier; Step S203: Confirm that the contact identifier is a contact, then obtain the constraint Jacobian and motion Jacobian based on the current end position, the joint space constraint, and the end position Jacobian; Step S204: Under the preset desired end trajectory, generate motion subspace control force based on the current end position; Step S205: Obtain the constraint direction equivalent inertia based on the constraint Jacobian and the dynamic model, and generate the coupling prediction bias based on the constraint direction equivalent inertia, the constraint Jacobian, the motion Jacobian, the motion subspace control force, the dynamic model and the current joint configuration; Step S206: Based on the coupling prediction deviation, the equivalent inertia of the constraint direction, the motion Jacobian, and the constraint Jacobian, the final joint torque is obtained, and the robot is controlled to grind the target workpiece based on the final joint torque; Step S207: Obtain the grinding operation status and confirm that the grinding operation status is not grinding completed. Then obtain feedback information and obtain the corrected joint space constraint based on the feedback information. Use the corrected joint space constraint as the joint space constraint to re-execute the force control step until the grinding operation status is grinding completed, and obtain the grinding result.

[0032] The above embodiments generate an end-effector position Jacobian based on the current joint configuration and the current end-effector position. This end-effector position Jacobian is then combined with the current external force information and the current joint configuration to obtain an estimated end-effector force matching the current robot state. A contact flag is then obtained based on this estimated end-effector force. If the contact flag indicates contact, it signifies that the robot end-effector has made contact with the target workpiece surface. At this point, based on the current end-effector position, joint space constraints, and the end-effector position Jacobian, a constraint Jacobian corresponding to the contact force direction to be controlled (normal direction of the target workpiece surface) and a motion Jacobian corresponding to the tangential motion direction of the target workpiece surface are obtained. Finally, a motion subspace control force is generated based on the desired end-effector trajectory and the current end-effector position. This embodiment obtains the equivalent inertia of the constraint direction based on the above-mentioned constraint Jacobian and dynamic model. Then, using the equivalent inertia of the constraint direction, constraint Jacobian, motion Jacobian, motion subspace control force, dynamic model and current joint configuration, a coupling prediction deviation that can adapt to the current robot grinding condition is generated. The final joint torque grinding obtained based on the coupling prediction deviation, the equivalent inertia of the constraint direction, the motion Jacobian and the constraint Jacobian can effectively compensate for the real-time contact force deviation caused by the change of the target workpiece shape during the robot grinding process. Furthermore, based on the feedback signal, the joint space constraint is continuously corrected, which can ensure that the robot end effector and the target workpiece surface remain stably attached during the overall grinding process, thereby improving the contact force accuracy between the robot end effector and the target workpiece surface during the grinding process.

[0033] In one embodiment, a force control step is performed based on the dynamic model and joint space constraints. During the execution of a force control step, the current joint configuration is obtained. Current external force information and current end position Among them, external force information It is obtained from the output of a six-dimensional force or torque sensor or a momentum observer. This is based on the current joint configuration. and current end position Generate the current end position Jacobian .

[0034] Based on current external force information Current joint configuration And the end position Jacobi Based on the following relationship between external force and external torque: , Obtain the estimated end force And if the end position is Jacobi When the inverse is not necessarily reversible, a pseudo-inverse form is used for estimation. To obtain an estimate of the end external force Subsequently, the estimated end force was... Contact threshold The comparison yields the contact identifier flag_contact, specifically, in When the end is in contact with the target workpiece surface, it is considered that the end has made contact, and the contact flag flag_contact corresponds to the contact. It is the vector norm.

[0035] After confirming that the current contact identifier is a contact, then based on the current end position... Joint space constraints And the end position Jacobi Jacobi was bound by constraints. , recorded as And obtained the movement Jacobi , recorded as ; The preset desired terminal trajectory Next, based on the current end position Generate motion subspace control force as follows: ; in, , and These are all corresponding preset control parameters. Based on constraint Jacobian. The equivalent inertia of the constraint direction is obtained from the dynamic model. And based on the equivalent inertia of the constraint direction , constraint Jacobi , sports Jacobi Motion subspace control force Dynamic model and current joint configuration Generate Coupled Prediction Bias Based on the above coupling prediction bias Equivalent inertia in the direction of constraint , sports Jacobi and the constraint of Jacobi Obtain the final joint torque The final joint torque is issued. Control the robotic arm to grind the target workpiece.

[0036] If the current grinding operation status is not "grinding complete," meaning the robot has not completed the grinding task on the target workpiece, feedback information is obtained, and the joint space constraints are corrected based on the feedback information. This will correct the joint space constraints. The joint space constraints used in the next force control step are used to re-execute the force control step until the grinding operation status is "grinding complete" and the grinding result is obtained.

[0037] Furthermore, the step of obtaining the joint space constraints of the target workpiece surface and obtaining the robot's dynamic model includes: obtaining the contact point set of the target workpiece surface and fitting a fitted surface based on the contact point set; obtaining the joint space constraints based on the fitted surface; obtaining the robot's inertia term, Coriolis term, and gravity term, and obtaining the dynamic model based on the inertia term, the Coriolis term, and the gravity term.

[0038] The above embodiment first obtains the set of contact points on the surface of the target workpiece. Based on this set of contact points, a fitted surface reflecting the geometry of the workpiece surface is obtained. Then, the joint space constraint that conforms to the surface shape of the target workpiece is obtained through the fitted surface, reducing the grinding contact force deviation caused by joint space constraint errors, thereby improving the contact force accuracy between the end effector and the workpiece surface during the overall grinding process. This embodiment obtains a dynamic model based on the robot's inertia, Coriolis, and gravity terms, so that the subsequent generated coupling prediction deviation can reflect the interference of inertial force, Coriolis force, etc. on the contact force. This allows the robot to predict and compensate for the interference caused by the grinding operation motion when grinding at high speed based on the compensated final joint torque, ensuring that the end effector conforms to the workpiece surface and improving the contact force accuracy between the end effector and the target workpiece surface during the robot grinding process.

[0039] In one embodiment, the robot, guided by a teach pendant, moves slowly along the surface of the target workpiece to be processed, reducing the impact of velocity or acceleration coupling on contact point sampling and making the sampling trajectory closer to the true geometry of the workpiece surface. Simultaneously, a small constant force is applied in the normal direction under the teach pendant's guidance. To ensure continuous contact between the robot's end effector and the target workpiece surface, wherein, To demonstrate the correct direction of the teaching objective, This is the unit vector of the contact normal or constraint direction. Based on the above teaching, a fixed sampling period is used. Record the end pose or position point to obtain several sampling points, the first sampling points The following is how to obtain it: , ; A set of contact points is obtained by integrating several sampling points. ,in, This represents the total number of sampling points acquired. Optionally, when acquiring the contact point set, the joint configuration corresponding to each sampling point in the contact point set can also be acquired. Thus, the joint trajectory is obtained. .

[0040] Based on the above set of contact points The fitted surface was obtained by fitting methods such as least squares method, spline fitting method, and local polynomial fitting method. And the fitted surface satisfies Based on the fitted surface In the pre-set positive kinematics Obtaining joint space constraints And satisfy This joint space constraint is used to ensure that the end positions corresponding to the joint configuration at each moment during the grinding process must fall within the space constraint. superior.

[0041] Subsequently, the robot's inertial terms were obtained. Coriolis term and gravity term Based on the inertia term, Coriolis term, and gravity term, the dynamic model is obtained as follows: ; in, This refers to the joint position. For joint velocity, For joint acceleration, To control the torque, This is the equivalent joint torque of the external force.

[0042] Further, in the step of acquiring the grinding operation status and confirming that the grinding operation status is not grinding complete, then acquiring feedback information, obtaining corrected joint space constraints based on the feedback information, and re-executing the force control steps using the corrected joint space constraints as joint space constraints until the grinding operation status is grinding complete and the grinding result is obtained, the step of acquiring feedback information, obtaining corrected joint space constraints based on the feedback information, and re-executing the force control steps using the corrected joint space constraints as joint space constraints includes: acquiring feedback information from the robot, and acquiring a force tracking error sequence, a grinding trajectory position sequence, and an estimated environmental stiffness from the feedback information; obtaining an average force error based on the force tracking error sequence and the grinding trajectory sequence, and acquiring a normal displacement deviation based on the average force error and the estimated environmental stiffness; compensating the fitted surface based on the normal displacement deviation to generate a corrected surface, and obtaining corrected joint space constraints based on the corrected surface; using the corrected joint space constraints as joint space constraints, and re-executing the force control steps based on the joint space constraints.

[0043] The above embodiments obtain feedback information to extract the force tracking error sequence, the grinding trajectory position sequence, and the estimated environmental stiffness. The force tracking error sequence reflects the change of the error between the actual contact force and the expected force during the grinding process with grinding time. The grinding trajectory position sequence corresponds to the force tracking error sequence and can reflect the location where each error occurs. The estimated environmental stiffness reflects the resistance of the contact surface between the robot and the workpiece to deformation under external forces. Subsequently, this embodiment obtains the average force error based on the force tracking error sequence and the grinding trajectory sequence, and obtains the normal displacement deviation based on the average force error and the estimated environmental stiffness. Then, based on the normal displacement deviation, the fitted surface is compensated to generate a corrected surface, making the corrected surface more closely fit the true geometry of the workpiece. The corrected joint space constraint is obtained based on the corrected surface, and the corrected joint space constraint is used as the joint space constraint for the next force control step. This makes the coupling prediction deviation obtained in the next force control step more accurate, reduces the contact force deviation caused by the continuous wear and tear of the workpiece and the change in surface shape during continuous grinding, and improves the contact force accuracy between the robot end effector and the workpiece surface.

[0044] In one embodiment, if it is confirmed that the grinding operation status is not "grinding complete", feedback information from the robot is obtained, and a force tracking error sequence is obtained from the feedback information. Grinding trajectory position sequence and estimating environmental stiffness Based on this force tracking error sequence and polishing trajectory sequence Obtain the average force error The average force error This represents the statistical average of the force error falling within the neighborhood or grid of the corresponding location.

[0045] Based on the above average force error and estimating environmental stiffness Based on the approximate linear contact model, i.e., Hooke's law, the normal displacement deviation corresponding to the force error is obtained. for: ; Based on normal displacement deviation Fitted surface Compensation generates modified surfaces Specifically: ; Subsequently, based on the modified surface Obtain corrected joint space constraints Specifically: ; Its satisfaction The joint space constraint should be modified. As a joint space constraint, the force control steps are re-executed based on the updated joint space constraint until the grinding operation status is confirmed as grinding complete and the grinding result is obtained.

[0046] Furthermore, it also includes: confirming that the contact identifier is not in contact, then obtaining motion control equivalent effect based on the current end position under the preset desired end trajectory; extracting the robot gravity term from the dynamic model according to the current joint configuration, and obtaining the joint torque based on the robot gravity term, the motion control equivalent effect, and the Jacobian of the end position; controlling the robot action based on the joint torque to obtain the robot control state; confirming that the robot control state is control completed, then re-executing the force control step.

[0047] In the above embodiments, when the contact marker is not in contact, motion control and other effects are obtained based on the current end position under the preset desired end trajectory. The robot gravity term is extracted from the dynamic model according to the current joint configuration. Based on the gravity term, motion control and other effects, and the Jacobian of the end position, a joint torque that can offset the influence of the robot's own gravity on its motion is obtained. Based on the joint torque, the robot's movement is controlled, which can reduce the situation where the robot end falls or deviates due to gravity. When the end is not in contact with the workpiece surface, the robot can smoothly approach the workpiece surface until the end contacts the workpiece surface, so that the grinding can start stably after contact. In the initial grinding, the robot end can stably fit with the target workpiece surface, thereby improving the contact force accuracy between the end and the workpiece surface during the overall grinding operation.

[0048] In one embodiment, when the contact identifier does not correspond to a contact, the current end position is used as the basis. The preset desired terminal trajectory The following can achieve the same effect as motion control. , specifically: ; Based on the current joint configuration, the robot's gravity term is extracted from the dynamic model. And based on the robot's gravity term Effects such as motion control And the end position Jacobi Obtain joint torque Specifically: ； Based on joint torque The robot's control state is obtained by controlling its movements; if the current robot control state is confirmed to be "control complete," it indicates that the robot has completed the action corresponding to the joint torque, and the force control steps are executed again. Therefore, this embodiment enables the robot to safely approach the target workpiece surface, providing a smooth transition for subsequent contact processes.

[0049] Further, the step of confirming that the contact identifier is a contact, and then obtaining the constraint Jacobian and motion Jacobian based on the current end position, the joint space constraint, and the end position Jacobian, includes: confirming that the contact identifier is a contact, then obtaining the surface gradient based on the current end position and the joint space constraint; generating the constraint Jacobian based on the surface gradient and the end position Jacobian, and obtaining the current normal direction based on the surface gradient; and generating the motion Jacobian based on the current normal unit direction.

[0050] In one embodiment, joint space constraint Can be recorded as After confirming that the contact identifier corresponds to the contact, based on the current end position... and joint space constraints Obtaining the surface gradient Specifically: ; in, , and Current end position The corresponding three-dimensional coordinates.

[0051] Based on surface gradient And the end position Jacobi Generate Constrained Jacobi Specifically: ; Subsequently, based on surface gradient Get the current normal direction According to the current direction of the unit Generate motion projection Then, based on the motion projection Mapping yields the motion Jacobian .

[0052] Further, the step of obtaining the constraint direction equivalent inertia based on the constraint Jacobian and the dynamic model, and generating a coupling prediction deviation based on the constraint direction equivalent inertia, the constraint Jacobian, the motion Jacobian, the motion subspace control force, the dynamic model, and the current joint configuration includes: extracting robot inertia terms and robot Coriolis terms from the dynamic model; obtaining the constraint direction equivalent inertia based on the constraint Jacobian and the robot inertia terms; obtaining inertial coupling compensation based on the constraint direction equivalent inertia, the constraint Jacobian, the motion Jacobian, the robot inertia terms, and the motion subspace control force; obtaining velocity coupling compensation based on the current joint configuration, the constraint direction equivalent inertia, the robot Coriolis term, the robot inertia terms, and the constraint Jacobian; and generating a coupling prediction deviation based on the inertial coupling compensation and the velocity coupling compensation.

[0053] The above embodiments obtain the equivalent inertia of the constraint direction based on the constraint Jacobian and the robot inertia term. Inertial coupling compensation is obtained based on the equivalent inertia of the constraint direction, the constraint Jacobian, the motion Jacobian, the robot inertia term, and the motion subspace control force to offset the interference force generated by the robot's inertial force in the normal direction of the workpiece surface during tangential acceleration. Furthermore, velocity coupling compensation is obtained based on the current joint configuration, the equivalent inertia of the constraint direction, the robot's Coriolis eccentricity term, the robot inertia term, and the constraint Jacobian to offset the dynamic deviation caused by speed during high-speed grinding. Subsequently, this embodiment generates a coupling prediction deviation based on inertial coupling compensation and velocity coupling compensation to compensate for the interference force caused by tangential acceleration and speed. This ensures that even when the curvature of the joint surface changes drastically during high-speed grinding along the workpiece surface, the actual contact force of the end effector closely follows the expected force, allowing the robot end effector to stably adhere to the target workpiece surface and improving the contact force accuracy between the end effector and the workpiece surface during the overall grinding operation.

[0054] In one embodiment, robot inertial terms are extracted from the dynamic model. And the robot Coriolis centrifuge Based on the current constraints, Jacobi and robot inertial terms Obtain the equivalent inertia of the constrained direction Specifically: ; Subsequently, based on the equivalent inertia of the constraint direction , constraint Jacobi , sports Jacobi Robot inertia and motion subspace control force To obtain inertial coupling compensation as Based on the current joint configuration Equivalent inertia in the direction of constraint Robotic Coriolis Centrifuge Robot inertia and the constraint of Jacobi Obtain speed coupling compensation as Then, based on the above inertial coupling compensation and velocity coupling compensation, a coupling prediction deviation is generated. Specifically: .

[0055] The compensation terms obtained in the above embodiments can reflect and compensate for the dynamic crosstalk of tangential motion to normal force.

[0056] Further, the step of obtaining the final joint torque based on the coupling prediction deviation, the equivalent inertia of the constraint direction, the motion Jacobian, and the constraint Jacobian, and controlling the robot to grind the target workpiece based on the final joint torque, includes: obtaining a normal control force based on the coupling prediction deviation under a preset desired normal contact force; extracting the robot gravity term from the dynamic model based on the current joint configuration; obtaining the final joint torque based on the normal control force, the motion subspace control force, the motion Jacobian, and the constraint Jacobian; and controlling the robot to grind the target workpiece based on the final joint torque.

[0057] The above embodiment obtains the normal control force based on the coupling prediction deviation under the preset expected normal contact force. This normal control force can offset the coupling deviation predicted by the coupling prediction deviation, and can make the actual contact force in the constraint direction during subsequent robot grinding approach the expected value. After obtaining the normal control force, the final joint torque is obtained based on the normal control force, the motion subspace control force, the motion Jacobian, and the constraint Jacobian. The obtained final joint torque fits the actual robot grinding conditions, so that the robot end is in close contact with the target workpiece surface, and the contact force accuracy between the end and the workpiece surface is improved during the overall grinding operation.

[0058] In one embodiment, based on coupling prediction bias Under the pre-set expected normal contact force Obtaining normal control force Then, based on the current joint configuration Extracting the robot's gravity term from the dynamic model Subsequently, based on normal control force Motion subspace control force , sports Jacobi and the constraint of Jacobi Obtain the final joint torque , specifically: ; in, What is being controlled is the normal force. What is controlled is the tangential motion; based on the aforementioned final joint torque Control the robot to grind the target workpiece.

[0059] The above embodiments can improve the contact force accuracy between the end of the robot grinding process and the surface of the target workpiece, so as to adapt to high-speed grinding scenarios.

[0060] This embodiment also provides a robot constant force grinding system for implementing a robot constant force grinding method as described in any of the preceding embodiments, comprising: a joint space constraint and dynamic model acquisition module for acquiring the joint space constraints of the target workpiece surface and acquiring the robot's dynamic model; a force-controlled grinding module for executing force control steps based on the dynamic model and the joint space constraints to obtain a grinding result; the force control steps include: acquiring the current joint configuration, current external force information, and current end effector position, and generating an end effector position Jacobian based on the current joint configuration and current end effector position; acquiring an estimated end effector external force based on the current external force information, current joint configuration, and the end effector position Jacobian, and comparing the estimated end effector external force with a preset contact determination threshold to obtain a contact identifier; confirming that the contact identifier is a contact, then obtaining a constraint Jacobian and motion based on the current end effector position, the joint space constraints, and the end effector position Jacobian. Jacobi; Under the preset desired end-effector trajectory, a motion subspace control force is generated based on the current end-effector position; Based on the constraint Jacobi and the dynamic model, the constraint direction equivalent inertia is obtained, and based on the constraint direction equivalent inertia, the constraint Jacobi, the motion Jacobi, the motion subspace control force, the dynamic model, and the current joint configuration, a coupling prediction deviation is generated; Based on the coupling prediction deviation, the constraint direction equivalent inertia, the motion Jacobi, and the constraint Jacobi, the final joint torque is obtained, and based on the final joint torque, the robot is controlled to grind the target workpiece; The grinding operation status is obtained, and if it is confirmed that the grinding operation status is not grinding complete, feedback information is obtained, and the corrected joint space constraint is obtained based on the feedback information. The corrected joint space constraint is used as the joint space constraint to re-execute the force control steps until the grinding operation status is grinding complete, and the grinding result is obtained.

[0061] It is understood that the above system embodiments correspond to the method embodiments of the present invention, and can implement the robot constant force grinding method provided by any of the above method embodiments of the present invention.

[0062] It should be noted that the system embodiments described above are merely illustrative, and some or all of the modules can be selected to achieve the purpose of this embodiment according to actual needs. Furthermore, in the accompanying drawings of the system embodiments provided by this invention, the connection relationships between modules indicate that they have communication connections, which can be specifically implemented as one or more communication buses or signal lines. Those skilled in the art can understand and implement this without any creative effort.

[0063] The present invention also provides a terminal device, including a processor, a memory, and a computer program stored in the memory and configured to be executed by the processor, wherein when the processor executes the computer program, it implements any of the above-described robotic constant force grinding methods.

[0064] The terminal device may be a desktop computer, laptop, handheld computer, or cloud server, etc. The terminal device may include, but is not limited to, a processor and a memory.

[0065] The processor can be a Central Processing Unit (CPU), or other general-purpose processors, digital signal processors (DSPs), application-specific integrated circuits (ASICs), field-programmable gate arrays (FPGAs), or other programmable logic devices, discrete gate or transistor logic devices, discrete hardware components, etc. A general-purpose processor can be a microprocessor or any conventional processor. The processor is the control center of the terminal device, connecting all parts of the terminal device via various interfaces and lines.

[0066] The present invention also provides a computer-readable storage medium, comprising: a stored computer program, wherein, when the computer program is executed, it controls the device on which the computer-readable storage medium is located to perform any of the above-described robotic constant force grinding methods.

[0067] The above embodiments generate an end-effector position Jacobian based on the current joint configuration and the current end-effector position. This end-effector position Jacobian is then combined with the current external force information and the current joint configuration to obtain an estimated end-effector force matching the current robot state. A contact identifier is then obtained based on this estimated end-effector force. If the contact identifier indicates contact, then based on the current end-effector position, joint space constraints, and the end-effector position Jacobian, a constraint Jacobian corresponding to the contact force direction to be controlled (normal direction of the target workpiece surface) and a motion Jacobian corresponding to the tangential motion direction of the target workpiece surface are obtained. Subsequently, this embodiment obtains the equivalent inertia of the constraint direction based on the aforementioned constraint Jacobian and dynamic model. Then, using the equivalent inertia of the constraint direction, constraint Jacobian, motion Jacobian, motion subspace control force, dynamic model, and current joint configuration, a coupling prediction deviation that can adapt to the current robot grinding condition is generated. The final joint torque grinding obtained based on the coupling prediction deviation, the equivalent inertia of the constraint direction, the motion Jacobian, and the constraint Jacobian can effectively compensate for the real-time contact force deviation caused by the change in the shape of the target workpiece during continuous grinding. Furthermore, based on the feedback signal, the joint space constraint is continuously corrected, which can ensure that the robot end effector and the target workpiece surface remain stably attached during the overall grinding process, thereby improving the contact force accuracy between the robot end effector and the target workpiece surface during the grinding process.

[0068] The above description represents the preferred embodiments of the present invention. It should be noted that those skilled in the art can make various improvements and modifications without departing from the principles of the present invention, and these improvements and modifications are also considered to be within the scope of protection of the present invention.

Claims

1. A robotic constant-force grinding method, characterized in that, Includes the following steps: Obtain the joint space constraints on the surface of the target workpiece and obtain the dynamic model of the robot; The grinding result is obtained by executing force control steps based on the dynamic model and the joint space constraints. The force control steps include: Obtain the current joint configuration, current external force information, and current end effector position, and generate the end effector position Jacobian based on the current joint configuration and current end effector position; Based on the current external force information, the current joint configuration, and the Jacobian of the end position, the estimated end external force is obtained, and the estimated end external force is compared with a preset contact determination threshold to obtain a contact identifier; If the contact identifier is confirmed as contact, then the constraint Jacobian and motion Jacobian are obtained based on the current end position, the joint space constraint, and the end position Jacobian. Under the preset desired end trajectory, a motion subspace control force is generated based on the current end position; The constraint direction equivalent inertia is obtained based on the constraint Jacobian and the dynamic model, and the coupling prediction bias is generated based on the constraint direction equivalent inertia, the constraint Jacobian, the motion Jacobian, the motion subspace control force, the dynamic model and the current joint configuration. The final joint torque is obtained based on the coupling prediction deviation, the equivalent inertia of the constraint direction, the motion Jacobian, and the constraint Jacobian, and the robot is controlled to grind the target workpiece based on the final joint torque. If the grinding operation status is not obtained and it is confirmed that the grinding operation status is not grinding complete, feedback information is obtained, and the joint space constraint is corrected based on the feedback information. The force control step is re-executed using the corrected joint space constraint as the joint space constraint until the grinding operation status is grinding complete, and the grinding result is obtained.

2. The robotic constant-force grinding method as described in claim 1, characterized in that, The process of obtaining the joint space constraints of the target workpiece surface and obtaining the robot's dynamic model includes: Obtain the set of contact points on the surface of the target workpiece, and fit a surface based on the set of contact points; The joint space constraints are obtained based on the fitted surface; Obtain the robot's inertial, Coriolis, and gravitational terms, and obtain a dynamic model based on the inertial, Coriolis, and gravitational terms.

3. The robotic constant-force grinding method as described in claim 2, characterized in that, The process of obtaining the grinding operation status and confirming that the grinding operation status is not grinding complete, obtaining feedback information, and obtaining a corrected joint space constraint based on the feedback information, and re-executing the force control step using the corrected joint space constraint as the joint space constraint, until the grinding operation status is grinding complete and the grinding result is obtained, includes: Obtain feedback information from the robot, and extract force tracking error sequence, grinding trajectory position sequence and estimated environmental stiffness from the feedback information; The average force error is obtained based on the force tracking error sequence and the grinding trajectory sequence, and the normal displacement deviation is obtained based on the average force error and the estimated environmental stiffness. Based on the normal displacement deviation, a modified surface is generated by compensating the fitted surface, and the modified joint space constraint is obtained based on the modified surface. The modified joint space constraint is used as the joint space constraint, and the force control step is re-executed based on the joint space constraint.

4. A robot constant force grinding method as described in any one of claims 1 to 3, characterized in that, Also includes: If it is confirmed that the contact identifier is not a contact, then motion control and other effects can be obtained based on the current end position under the preset desired end trajectory; Based on the current joint configuration, the robot gravity term is extracted from the dynamic model, and the joint torque is obtained based on the robot gravity term, the motion control efficiency, and the end-effector Jacobian. The robot's control state is obtained by controlling the robot's movements based on the joint torque. Once the robot control status is confirmed to be complete, the force control steps are executed again.

5. A robot constant force grinding method as described in any one of claims 1 to 3, characterized in that, If the contact identifier is confirmed as contact, then the constraint Jacobian and motion Jacobian are obtained based on the current end-effector position, the joint space constraint, and the end-effector position Jacobian, including: If the contact identifier is confirmed as contact, the surface gradient is obtained based on the current end position and the joint space constraints; A constrained Jacobian is generated based on the surface gradient and the end position Jacobian, and the current normal direction is obtained based on the surface gradient; Generate a motion Jacobian based on the current normal unit direction.

6. The robotic constant-force grinding method as described in claim 5, characterized in that, The process of obtaining the equivalent inertia of the constraint direction based on the constraint Jacobian and the dynamic model, and generating a coupling prediction bias based on the equivalent inertia of the constraint direction, the constraint Jacobian, the motion Jacobian, the motion subspace control force, the dynamic model, and the current joint configuration, includes: The robot inertial term and the robot Coriolis term are extracted from the dynamic model; The constraint direction equivalent inertia is obtained based on the constraint Jacobian and the robot inertia term; Inertial coupling compensation is obtained based on the equivalent inertia of the constraint direction, the constraint Jacobian, the motion Jacobian, the robot inertial term, and the motion subspace control force; Velocity coupling compensation is obtained based on the current joint configuration, the equivalent inertia of the constraint direction, the robot's Coriolis term, the robot's inertia term, and the constraint Jacobian. The coupling prediction deviation is generated based on the inertial coupling compensation and the velocity coupling compensation.

7. The robot constant force grinding method as described in claim 5, characterized in that, The step of obtaining the final joint torque based on the coupling prediction deviation, the equivalent inertia of the constraint direction, the motion Jacobian, and the constraint Jacobian, and controlling the robot to grind the target workpiece based on the final joint torque, includes: Under the preset expected normal contact force, the normal control force is obtained based on the coupling prediction deviation; Based on the current joint configuration, the robot's gravity term is extracted from the dynamic model; The final joint torque is obtained based on the normal control force, the motion subspace control force, the motion Jacobian, and the constraint Jacobian. The robot is controlled to grind the target workpiece based on the final joint torque.

8. A robotic constant-force grinding system, characterized in that, A robotic constant-force grinding method as described in any one of claims 1 to 7, comprising: The joint space constraint and dynamic model acquisition module is used to acquire the joint space constraints of the target workpiece surface and the dynamic model of the robot. The force-controlled grinding module is used to execute force control steps based on the dynamic model and the joint space constraints to obtain the grinding result; The force control steps include: Obtain the current joint configuration, current external force information, and current end effector position, and generate the end effector position Jacobian based on the current joint configuration and current end effector position; Based on the current external force information, the current joint configuration, and the Jacobian of the end position, the estimated end external force is obtained, and the estimated end external force is compared with a preset contact determination threshold to obtain a contact identifier; If the contact identifier is confirmed as contact, then the constraint Jacobian and motion Jacobian are obtained based on the current end position, the joint space constraint, and the end position Jacobian. Under the preset desired end trajectory, a motion subspace control force is generated based on the current end position; The constraint direction equivalent inertia is obtained based on the constraint Jacobian and the dynamic model, and the coupling prediction bias is generated based on the constraint direction equivalent inertia, the constraint Jacobian, the motion Jacobian, the motion subspace control force, the dynamic model and the current joint configuration. The final joint torque is obtained based on the coupling prediction deviation, the equivalent inertia of the constraint direction, the motion Jacobian, and the constraint Jacobian, and the robot is controlled to grind the target workpiece based on the final joint torque. If the grinding operation status is not obtained and it is confirmed that the grinding operation status is not grinding complete, feedback information is obtained, and the joint space constraint is corrected based on the feedback information. The force control step is re-executed using the corrected joint space constraint as the joint space constraint until the grinding operation status is grinding complete, and the grinding result is obtained.

9. A terminal device, characterized in that, The method includes a processor, a memory, and a computer program stored in the memory and configured to be executed by the processor, wherein when the processor executes the computer program, it implements a robotic constant force grinding method as described in any one of claims 1 to 7.

10. A computer-readable storage medium, characterized in that, include: A stored computer program, wherein, when the computer program is executed, it controls the device containing the computer-readable storage medium to perform a robotic constant-force grinding method as described in any one of claims 1 to 7.

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