Robot optical element multi-axis linkage force control polishing method and device and storage medium

Abstract

The application discloses a robot optical element multi-axis linkage force control polishing method and device and a storage medium, and relates to the technical field of robot polishing. First, a multi-body kinematics model of a robot, an additional axis and an optical element to be polished is constructed, a homogeneous coordinate transformation relationship of multiple coordinate systems is established, and an initial machining path is determined. Then, global pose matching optimization is performed on the initial machining path to obtain a target machining path. Next, the workpiece pose is adjusted through an additional axis workbench, so that the polishing tool and the machining point maintain a fixed relative pose. Finally, the polishing force fluctuation is compensated in real time through an end force control mechanism, force deviation caused by robot positioning error and joint deformation is inhibited, and constant force stability in the polishing process is ensured. Ultimately, efficient and high-precision continuous polishing of the whole surface of the optical element to be polished is realized.

Description

Technical Field

[0001] This application relates to the field of robotic polishing technology, specifically to a multi-axis dynamic control polishing method, apparatus, and storage medium for robotic optical elements. Background Technology

[0002] High-precision optical components are widely used in national optical engineering, military defense, aerospace and other fields due to their superior optical performance. Therefore, developing mass production capabilities for high-precision optical components is crucial. Robotic polishing technology, as a promising emerging polishing technology, offers advantages such as high processing flexibility, strong scalability, and low cost, and can meet the high-efficiency polishing requirements of optical components.

[0003] However, due to the robot's serial structure, its rigidity and machining accuracy are poor, making it impossible to maintain a constant tool pressure during polishing. This leads to unstable polishing force and severely affects the robot's polishing accuracy. Secondly, due to the robot's limited arm span, it suffers from insufficient machining range and poor machining posture when processing steep, large-diameter components. In applications such as surface trimming, the robot's insufficient dynamic response also reduces the machining accuracy of robot polishing. Summary of the Invention

[0004] The purpose of this application is to provide a multi-axis dynamic control polishing method, device and storage medium for robot optical components, in order to solve the problems of low processing accuracy caused by insufficient polishing range, poor posture and unstable force in traditional robot polishing technology.

[0005] To achieve the above objectives, the first aspect of this application provides a multi-axis dynamic controlled polishing method for robotic optical elements, comprising: Construct a multibody kinematics model of the robot, the additional axis, and the optical element to be polished; establish the homogeneous coordinate transformation relationship between the base coordinate system, the tool coordinate system, the workpiece coordinate system, and the additional axis coordinate system; and determine the position and normal information of each machining point on the initial machining path. Using the joint combination of the robot and the additional axis as motion allocation variables, with the optimization objectives of expanding the processing range and improving the system stiffness and dynamic response characteristics, and with the joint limits and motion speed limits of the robot and the additional axis as constraints, global pose matching optimization is performed on the initial processing path to obtain the target processing path; Based on the pose and motion parameters of each processing point under the target processing path, the workpiece posture of the optical element to be polished is adjusted by the worktable of the additional axis, so that the polishing tool of the robot and the processing point maintain a preset fixed relative posture. The surface of the optical element to be polished is continuously polished along the target processing path, and the polishing force fluctuation is compensated in real time by the end force control mechanism of the polishing tool during the polishing process.

[0006] A second aspect of this application provides a multi-axis dynamic controlled polishing device for robotic optical elements, comprising: The construction module is used to build a multibody kinematics model of the robot, the additional axis, and the optical element to be polished, establish the homogeneous coordinate transformation relationship between the base coordinate system, the tool coordinate system, the workpiece coordinate system, and the additional axis coordinate system, and determine the position and normal information of each machining point on the initial machining path. The optimization module is used to perform global pose matching optimization on the initial machining path, with the joint combination of the robot and the additional axis as the motion allocation variable, and with the optimization objectives of expanding the machining range and improving the system stiffness and dynamic response characteristics, and with the joint limits and motion speed limits of the robot and the additional axis as constraints, to obtain the target machining path. The adjustment module is used to adjust the workpiece posture of the optical element to be polished through the worktable of the additional axis according to the pose and motion parameters of each processing point under the target processing path, so that the polishing tool of the robot and the processing point maintain a preset fixed relative posture. The compensation module is used to continuously polish the surface of the optical element to be polished along the target processing path, and to compensate for the fluctuation of polishing force in real time through the end force control mechanism of the polishing tool during the polishing process.

[0007] A third aspect of this application provides a computer-readable storage medium storing a program that can be loaded by a processor and executed by the above-described multi-axis dynamic control polishing method for robotic optical elements.

[0008] The beneficial effects of this application are: This application improves pose calculation accuracy and system control consistency by constructing a multi-body kinematic model of the robot, additional axes, and the optical element to be polished, and establishing a homogeneous coordinate transformation relationship across multiple coordinate systems. Through global pose matching optimization of the robot and additional axis joint combinations, the processing range of large-diameter, high-steepness optical elements is expanded, improving robot processing stiffness and system dynamic response performance. The workpiece posture is adjusted by the additional axis worktable, maintaining a fixed relative posture between the polishing tool and the processing point, stabilizing the processing posture, and reducing fluctuations in robot motion amplitude and stiffness. Real-time compensation of polishing force fluctuations by the end effector suppresses force deviations caused by robot positioning errors and joint deformation, ensuring constant force stability during the polishing process. Ultimately, efficient and high-precision continuous polishing of the entire surface of the optical element to be polished is achieved.

[0009] Other features and advantages of this application will be described in detail in the following detailed description section. Attached Figure Description

[0010] Figure 1 This is a schematic flowchart of a multi-axis dynamic control polishing method for robotic optical elements provided in an embodiment of this application; Figure 2 This is a schematic diagram of a power-controlled polishing system that integrates a robot and a single-axis rotary table, as provided in one embodiment of this application. Figure 3 This is a schematic diagram of a multibody kinematics model with the C-axis as an additional axis provided in one embodiment of this application; Figure 4 This is a schematic diagram of a robot's path planning and constraint setting in conjunction with the C-axis, provided in one embodiment of this application. Figure 5 This is a schematic diagram of the C-axis change curve before and after the linkage constraint between the robot and the C-axis provided in one embodiment of this application; Figure 6 This is a schematic diagram comparing the robot path before and after C-axis linkage optimization, provided in one embodiment of this application; Figure 7 This is a schematic diagram of a power-controlled polishing system that combines a robot with a dual-axis swing table, provided in another embodiment of this application. Figure 8 This is a schematic diagram of a multibody kinematics model with the AB axis as an additional axis, provided in another embodiment of this application; Figure 9 This is a schematic diagram comparing the robot path before and after the optimization of the robot's linkage with the AB axis, provided in another embodiment of this application; Figure 10 This is a schematic diagram of the structure of a multi-axis dynamic control polishing device for robotic optical elements provided in the embodiments of this application.

[0011] Explanation of reference numerals in the attached figures 1. Robot; 2. Polishing tool; 3. Optical component to be polished; 4. C-axis; 5. A-axis; 6. B-axis. Detailed Implementation

[0012] The technical solutions of the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this application, and 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.

[0013] In the description of this application, it should be understood that the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of indicated technical features. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of the stated features. In the description of this application, "a plurality of" means two or more, unless otherwise explicitly specified. Details are set forth in the following description for illustrative purposes. It should be understood that those skilled in the art will recognize that this application can be implemented without using these specific details. In other instances, well-known structures and processes will not be described in detail to avoid unnecessarily obscuring the description of this application. Therefore, this application is not intended to be limited to the embodiments shown, but rather to be consistent with the broadest scope of the principles and features disclosed herein.

[0014] Figure 1 This is a schematic flowchart illustrating a multi-axis dynamic controlled polishing method for robotic optical elements provided in an embodiment of this application. Figure 1 As shown, the multi-axis dynamic control polishing method for robot optical components may include steps 101-104, which will be described in detail below.

[0015] Step 101: Construct a multibody kinematic model of the robot, the additional axis, and the optical element to be polished; establish the homogeneous coordinate transformation relationship between the base coordinate system, the tool coordinate system, the workpiece coordinate system, and the additional axis coordinate system; and determine the position and normal information of each machining point on the initial machining path.

[0016] A multibody kinematics model is a holistic model describing the motion transmission and coordinate transformation between the robot, additional axes, workpiece, and tool. An additional axis is a rotary or oscillating axis integrated into the polishing table and controlled in conjunction with the robot, used to assist in adjusting the workpiece's posture. As an example, the base coordinate system is established at the center point of the robot's base, serving as the reference coordinate system for the entire system's motion control. The workpiece coordinate system is established at the center point of the upper surface of the optical element to be polished, used for path planning and machining point positioning, and its direction is consistent with the base coordinate system. The tool coordinate system is established at the end of the polishing tool, with the Z-axis aligned with the tool's axis, used to describe the relative pose of the tool and workpiece. The additional axis coordinate system is established at the rotation / oscillation center of the additional axis table, used to describe the rotation / oscillation motion of the additional axis and the workpiece's posture transformation.

[0017] Then, by obtaining the fixed translation and rotation transformation relationships between the robot, additional axes, workpiece, and tool through pose calibration, a homogeneous coordinate transformation relationship for the multi-body system is constructed. The homogeneous coordinate transformation relationship is a unified expression of the coordinate mapping relationship between rotation and translation, used to achieve unified pose solving across multiple coordinate systems. Next, an initial machining path is planned in the workpiece coordinate system, and the position coordinates and surface normal vectors of each machining point are extracted to form an initial machining point pose matrix containing position and normal information. The initial machining path is an unoptimized, original machining trajectory planned solely based on the workpiece surface. By establishing a unified and accurate multi-coordinate system mapping relationship, the uniqueness and accuracy of the pose solution are ensured, providing a reliable geometric and kinematic foundation for subsequent linkage control and path optimization.

[0018] Step 102: Using the joint combination of the robot and the additional axis as the motion allocation variable, with the optimization objectives of expanding the processing range and improving the system stiffness and dynamic response characteristics, and with the joint limits and motion speed limits of the robot and the additional axis as constraints, perform global pose matching optimization on the initial processing path to obtain the target processing path.

[0019] Motion assignment variables refer to the variables that rationally allocate the trajectory motion task between the robot and the additional axes. First, the combination of robot joints and additional axis joints is used as the motion assignment variable, and the pose of each processing point is solved based on a multi-body kinematics model. Then, three joint optimization objectives are set to achieve global pose matching optimization of the initial processing path. Specifically, global pose matching optimization means uniformly solving the pose of all points along the entire path, ensuring continuity, no conflicts, and optimality.

[0020] Specifically, by using an additional axis to move the optical element to be polished, the processing point is incorporated into the robot's effective workspace to expand the processing range. Limit constraints refer to ensuring that the robot and the additional axis do not exceed the safe range of angles and speeds allowed by the mechanical structure. For example, the range of motion of the robot's joints is constrained to maintain it within a high-stiffness posture range to reduce stiffness fluctuations. The additional axis undertakes the main motion of trajectory feed, reducing the robot's dynamic following error and improving the system's dynamic response characteristics. Using the robot's joint angle limits, speed limits, and the additional axis's rotational and speed limits as constraints, the joint angles corresponding to all processing points along the entire path are uniformly calculated and globally matched. The optimal motion combination that satisfies all constraints is selected, and the target processing path is output. The target processing path is the final polishing trajectory obtained after global pose optimization, motion allocation, and constraint selection of the initial processing path. It is suitable for the coordinated execution of the robot and the additional axis, has the optimal processing posture, and continuous motion without exceeding limits. In this way, large-diameter, high-steep optical elements can be reached across the entire area, significantly reducing the robot's motion range, improving processing stiffness and system dynamic performance, and avoiding posture degradation and motion exceeding limits.

[0021] Step 103: Based on the pose and motion parameters of each processing point under the target processing path, adjust the workpiece posture of the optical element to be polished through the worktable of the additional axis, so that the robot's polishing tool and the processing point maintain a preset fixed relative posture.

[0022] The auxiliary axis is a linkage axis integrated into the polishing table, including but not limited to single-axis rotary tables and dual-axis oscillating tables, and is uniformly linked and controlled by the robot system. The workpiece is fixed at the movable end of the auxiliary axis table and moves synchronously with the table. By adjusting the rotation angle of the auxiliary axis, each processing point is adjusted to a suitable polishing posture, so that the polishing tool at the end of the robot and the processing point always maintain a preset fixed relative posture. The fixed relative posture means that the posture relationship between the polishing tool and the processing point remains unchanged, and the processing can be completed without large-scale robot swing, thereby optimizing the robot's processing posture and reducing stiffness fluctuations.

[0023] As an example, if the additional axis is a single-axis rotary table, the optical element to be polished can be mounted on the rotation centerline. The table rotates around its own axis, causing the optical element to rotate and allowing any machining point on the surface of the optical element to sequentially enter a preset fixed machining generatrix. The fixed machining generatrix is ​​a fixed trajectory line on the optical element for the robot to process along a single direction. The robot is controlled to move only along this fixed machining generatrix, coordinating with the rotational motion of the single-axis rotary table to complete the entire surface machining.

[0024] As another example, if the additional axis is a dual-axis oscillating stage, the optical element to be polished can be mounted at the position of the common perpendicular line of the two axes of the dual-axis oscillating stage. Through the oscillating motion of the stage, the direction of the external normal at any processing point on the surface of the optical element to be polished is adjusted to be vertically upward. "External normal vertically upward" means adjusting the surface normal of the processing point to be vertically upward, facilitating vertical processing by the tool. The robot's polishing tool is controlled to maintain a vertically downward posture for processing; the robot does not need additional posture adjustments to cooperate with the dual-axis oscillating stage to complete the entire surface processing.

[0025] By actively undertaking the task of adjusting the workpiece posture with an additional axis, the robot's range of motion is significantly reduced, allowing the robot to remain in a high-rigidity posture range. This reduces stiffness fluctuations and positioning errors caused by posture changes, while also improving the system's dynamic response performance and enabling stable polishing of large-diameter, high-steep optical components.

[0026] Step 104: Continuously polish the surface of the optical element to be polished along the target processing path, and compensate for the fluctuation of polishing force in real time through the end force control mechanism of the polishing tool during the polishing process.

[0027] Following an optimized target processing trajectory, the robot drives the end-effector polishing tool to continuously polish the entire surface of the optical element to be polished. Continuous polishing of the entire surface refers to completing the entire surface processing in one go, improving efficiency and surface consistency. The processing process eliminates the need for partitioned processing, step-by-step processing, or repeated clamping, ensuring a continuous trajectory and stable posture throughout. During the entire polishing process, the end-effector force control mechanism installed at the robot's end collects the current polishing force signal in real time. The difference between the detected actual polishing force and the system's preset polishing force is calculated to obtain the polishing force fluctuation. The end-effector force control mechanism, installed at the robot's end, is an actuator used to detect and adjust the polishing pressure in real time. Then, based on this fluctuation, the axial feed pressure of the polishing tool is adjusted in real time to dynamically compensate for the polishing force fluctuation. For example, closed-loop adjustment eliminates pressure deviations, ensuring uniform material removal and offsetting polishing force deviations caused by robot positioning errors, joint stiffness deformation, and changes in processing posture, maintaining a constant polishing force output throughout the polishing process.

[0028] Real-time force control compensation effectively suppresses polishing force fluctuations caused by robot positioning errors, joint deformation, and posture changes, achieving constant force and stable polishing. Simultaneously, continuous full-surface processing significantly improves processing efficiency and surface consistency, ultimately enhancing the surface quality, surface accuracy, and processing stability of optical components.

[0029] This application improves pose calculation accuracy and system control consistency by constructing a multi-body kinematic model of the robot, additional axes, and the optical element to be polished, and establishing a homogeneous coordinate transformation relationship across multiple coordinate systems. Global pose matching optimization of the robot and additional axis joints expands the processing range of large-diameter, high-steepness optical elements, improving robot processing stiffness and system dynamic response performance. Adjusting the workpiece posture via the additional axis table maintains a fixed relative posture between the polishing tool and the processing point, stabilizing the processing posture and reducing fluctuations in robot motion amplitude and stiffness. Real-time compensation of polishing force fluctuations by the end effector suppresses force deviations caused by robot positioning errors and joint deformation, ensuring constant force stability during the polishing process. Ultimately, efficient and high-precision continuous polishing of the entire surface of the optical element is achieved.

[0030] In step 101, a base coordinate system can be established at the center point of the robot's base, a workpiece coordinate system can be established at the center point of the upper surface of the optical element to be polished, and a tool coordinate system can be established at the end of the polishing tool, and the workpiece coordinate system can be aligned with the direction of the base coordinate system.

[0031] Next, the additional axis and the optical element to be polished are calibrated. Pose calibration is the process of determining the fixed relative positions and orientations between components through measurement and calculation. Through pose calibration, the homogeneous coordinate transformation relationships between the base coordinate system, tool coordinate system, workpiece coordinate system, and additional axis coordinate system can be obtained, resulting in a multi-body kinematics model. The homogeneous coordinate transformation relationship uses a unified mathematical form to describe the coordinate mapping relationship between rotation and translation, achieving precise pose conversion between multiple coordinate systems.

[0032] Next, the initial machining path and machining points are planned in the workpiece coordinate system. Based on the position of each machining point and the surface normal, the pose parameters of each machining point on the initial machining path are determined. The pose parameters can simultaneously include comprehensive descriptive parameters of the machining point position coordinates and the surface normal direction. As an example, the robot's forward and inverse kinematics can be solved based on Denavit-Hartenberg (DH) parameters. The initial machining path is planned in the workpiece coordinate system, and the position coordinates and surface normal vectors of each machining point are extracted to form an initial machining point pose matrix containing position and normal information.

[0033] By establishing a unified and standardized multi-coordinate system and homogeneous coordinate transformation relationships, the precise and unique pose transformations between the robot, additional axes, workpiece, and tool are ensured. Standard kinematics solutions are completed based on DH parameters, improving the model's versatility and solution accuracy. Accurate acquisition of machining point positions and normal information provides a reliable data foundation and kinematic support for subsequent global pose optimization, attitude adjustment, and constant-force polishing.

[0034] In step 102, the joint combinations of the robot and the additional axis can be used as motion allocation variables to solve the pose of each processing point based on the multibody kinematics model. The joint combination is the combination of the angles of each joint of the robot and the joint angles of the additional axis; the motion allocation variables are adjustable parameters in the optimization process. The joint combinations formed by all the robot's joints and the rotary / swing joints of the additional axis are used as motion allocation variables, meaning the amount of movement of the robot and the additional axis is used as the adjustable parameters for optimization. The pose solution calculates the angles and postures that the robot and the additional axis should reach based on the position of the processing point. Based on the established multibody kinematics model and coordinate transformation relationships, the pose and angle that the robot and the additional axis need to reach can be calculated for each processing point on the initial processing path. For example, if a certain point on the optical element to be polished needs to be polished, the robot arm can be swung to a specific position and the turntable angle can be calculated to bring that point into the processing position.

[0035] Then, the optical element to be polished is moved by an additional axis, so that all processing points fall within the robot's effective workspace, which is the first optimization goal. The first optimization goal is to expand the range. Through the movement of the additional axis, areas that the robot cannot reach become processable areas, bringing all processing points into the robot's effective workspace to achieve full surface accessibility. For example, if the edge of a large-diameter optical element exceeds the robot's arm span, after the turntable rotates, the edge point moves to the front of the robot, achieving full-diameter coverage. In this way, edges, dead corners, and steep areas that the robot could not reach before can be processed by rotating the turntable / swing table.

[0036] Constraining the robot's joint movement range to maintain it within a high-stiffness posture range serves as the second optimization objective. This second objective aims to improve system stiffness by limiting the robot's joint movement range, keeping it within a posture range characterized by minimal deformation and high stability. For example, when machining steep optical components, by rotating the stage to ensure the outward normal of the edge machining points is vertically upward, the robot only needs to move within a small area in front of it in a fixed posture, resulting in greater stability and less deformation under stress. This avoids the problem of poor dynamic stiffness during machining due to large-range, large-angle movements, leading to unsatisfactory final component machining results. Optimization significantly reduces the robot's range of motion and the angles of movement of each joint, improving dynamic stiffness and ultimately enhancing machining performance.

[0037] The third optimization objective is to reduce the robot's following error by having the auxiliary axis handle the main motion component of the trajectory feed. This third objective aims to improve dynamic response by having the faster-responding auxiliary axis handle the main motion. In other words, the auxiliary stage has low inertia and fast response, making it suitable for high-speed feed. The robot has high inertia and slow response, so its movement should be minimized, thereby reducing robot tracking error and improving trajectory accuracy. For example, in grating machining, the rotary table rotates at high speed for the main motion, while the robot moves only slowly, resulting in a more accurate trajectory and less vibration.

[0038] Next, the first, second, and third optimization objectives are combined as a joint optimization objective. This joint optimization objective simultaneously considers machining range, stiffness, and dynamic response to achieve optimal overall performance. Then, the angular and speed limits of each joint of the robot, as well as the rotation and speed limits of the additional axes, are used as constraints. These constraints are physical limits that cannot be exceeded during the optimization process. Examples include the angular limits of each joint, the speed limits, the rotation / swing angle limits of the additional axes, and the speed limits of the additional axes. The joint angle limit is the maximum / minimum angle that the robot or additional axis can rotate, determined by the mechanical structure. The speed limit is the maximum permissible rotational speed of the joint, determined by the motor and drive capability.

[0039] Finally, the robot joint angles and additional axis joint angles corresponding to all machining points on the initial machining path are uniformly calculated and globally matched to select the optimal motion combination that satisfies all constraints, thus obtaining the target machining path. The optimal motion combination is a motion coordination method of the robot and additional axis that simultaneously satisfies the requirements of "accessibility, high stiffness, fast response, and no over-limit".

[0040] Through joint optimization of three aspects and global constraint screening, the processing range of large-diameter, high-steep optical components can be significantly expanded, enabling the robot to maintain a high-rigidity, low-deformation posture at all times. Having the auxiliary axis handle the main motion greatly improves the system's dynamic response speed and reduces following errors. Global pose matching ensures a continuous and smooth processing trajectory, avoiding exceeding limits and sudden posture changes, ultimately achieving high-precision, high-stability, and high-efficiency polishing of optical components.

[0041] The following example uses a single-axis rotary table with an additional axis as an illustration. A single-axis rotary table refers to a table that rotates around a fixed axis. In step 103, the optical element to be polished can first be mounted on the rotation center line of the single-axis rotary table, aligning the axis of the workpiece coordinate system with the axis of the additional axis coordinate system. The rotation center line is the rotation axis of the single-axis rotary table; mounting the optical element to be polished here ensures rotational symmetry and smooth movement. Then, the first target rotation angle of the single-axis rotary table is calculated based on the homogeneous coordinate transformation relationship. This first target rotation angle is the table rotation angle calculated based on the machining point pose and homogeneous coordinate transformation, causing the machining point to enter the fixed machining generatrix. The single-axis rotary table is controlled to rotate around its own axis, driving the optical element to be polished to rotate, so that any machining point on the surface of the optical element to be polished sequentially enters the preset fixed machining generatrix. Finally, the robot is controlled to move only along the fixed machining generatrix, coordinating with the rotational movement of the single-axis rotary table to complete the full-surface machining of the optical element to be polished.

[0042] Figure 2 This is a schematic diagram of a power-controlled polishing system that integrates a robot and a single-axis rotary table, as provided in one embodiment of this application. Figure 2 As shown, assuming the single-axis rotary table is the C-axis, the robot-driven power-controlled polishing system can include a robot 1, a polishing tool 2, an optical element 3 to be polished, and a C-axis 4. Robot 1 is the main actuator, a multi-jointed, serially connected structure, whose end effector drives the polishing tool 2 to perform polishing feed actions along the target path. Polishing tool 2 is the actuator at the end effector of robot 1, used to directly polish the surface of the optical element 3. The axis of polishing tool 2 is coaxial with the end effector of robot 1. The optical element 3 to be polished is fixedly mounted on the rotation center line of the C-axis 4, rotating synchronously with the table. The entire surface is polished through the linkage between the C-axis 4 and robot 1.

[0043] The optical element 3 to be polished is mounted on the rotation center line of the C-axis 4, with the workpiece coordinate system axis coinciding with the rotation axis of the worktable to ensure smooth and symmetrical rotational motion. The polishing tool 2 is fixed to the end of the robot 1 and is driven by the robot 1 to perform the feed action, maintaining the same posture as the end of the robot 1. The C-axis 4 actively adjusts the posture of the optical element 3 to be polished, so that the machining point enters the effective working space of the robot 1 and the fixed machining generatrix. The robot 1 only needs to move slightly in a fixed direction, and with the rotation of the auxiliary axis, it can complete the entire surface machining, significantly reducing the robot's movement range and improving machining rigidity and stability.

[0044] This structure expands the processing range of large-aperture optical components through the linkage of active attitude adjustment via an additional axis and small-range robot feed. The robot remains in a high-stiffness posture range throughout the process, reducing stiffness fluctuations. The additional axis undertakes the main motion, which improves the system's dynamic response performance and provides a stable hardware foundation for subsequent multibody kinematics modeling, path optimization, and constant-force polishing.

[0045] According to the optimization objectives proposed in the embodiments of this application, the selected optimization method is as follows: the optical element to be polished is installed at the C-axis position, and by rotating the C-axis, any processing point on the surface of the optical element to be polished is driven to a certain generatrix on the surface of the workpiece. In the embodiments of this application, the generatrix of the workpiece surface in the YZ plane of the workpiece coordinate system is selected as the processing generatrix of the robot. At the same time, the robot only moves within the generatrix and completes the full surface processing of the workpiece by linkage with the C-axis.

[0046] Figure 3 This is a schematic diagram of a multibody kinematics model with the C-axis as an additional axis, provided in one embodiment of this application. Figure 3 As shown, {O0} is the base coordinate system, which is established at the center point of the robot base. j} (1≤j≤6) represent the coordinate systems of the robot's six joints. {O t} is the tool coordinate system, and its Z-axis is... t Aligned with the tool axis direction. {O w} is the workpiece coordinate system, with its origin established at the center point of the workpiece's upper surface. c} is the additional axis (C-axis) coordinate system, with its origin at the center of rotation of the turntable surface, Z. c It coincides with the turntable.

[0047] Based on the topological model, the homogeneous coordinate transformation relationships between the base coordinate system, tool coordinate system, workpiece coordinate system, and additional axis coordinate system can be obtained: (1) In formula (1), ,in, (1≤j≤6) represent the joint angles of robot 1. Based on the DH parameters of robot 1, this formula can be solved by standard calculation methods for forward and inverse kinematics. To represent the spatial transformation relationship between the workpiece coordinate system and the C-axis coordinate system, it is first obtained by rotating the workpiece coordinate system by an angle C around the Z-axis of the turntable and then by translation. Let it be: (2) In formula (2), This indicates the positional relationship between the origin of the workpiece coordinate system and the origin of the rotated turntable coordinate system. Represents the rotational transformation along the C-axis, parameters This indicates the rotation angle around the Z-axis.

[0048] Let C represent the spatial transformation relationship of the C-axis in the robot's base coordinate system, and define its direction as being consistent with the direction of the {O0} coordinate system. It only includes translation transformation, and its translation vector is denoted as [ ].

[0049] This describes the transformation relationship between the polishing tool and the robot's end effector coordinate system. In this embodiment, it is assumed that the tool axis is aligned with the robot's 6-axis direction. Similarly, it only includes translation transformation, and its translation vector is denoted as [ ].

[0050] In formula (1), , The translation transformations in the equations represent fixed spatial transformation relationships between different parts of the motion system, which are usually obtained through calibration. The pose matrix representing the tool coordinate system in the workpiece coordinate system includes the position and normal information of each machining point on the initial machining path. Let the homogeneous pose matrix corresponding to any machining point P in the workpiece coordinate system be: (3) in, , , The tool's X-axis in the workpiece coordinate system The direction cosine of the down direction, , , The tool's Y-axis in the workpiece coordinate system The direction cosine of the down direction, , , The tool's Z-axis in the workpiece coordinate system The direction cosine of the down direction, , , Let the machining point P be in the workpiece coordinate system The three-dimensional position coordinates below.

[0051] When the Z-axis of the workpiece coordinate system coincides with the axis of the rotary table = =0. Let the tool's position coordinates in the turntable coordinate system be [ It can be represented by parametric equations: (4) (5) in, Let be the radius of rotation of the machining point relative to the axis of rotation of the rotary table. The azimuth angle of the machining point relative to the positive X-axis direction in the XY plane of the turntable.

[0052] At this point, the rotation angle of the C-axis can be obtained. Calculation formula: , (6) in, It is a two-input four-quadrant arctangent function. The first input parameter is the Y-axis coordinate component after rotation transformation, and the second input parameter is the X-axis coordinate component after rotation transformation.

[0053] When the C-axis moves according to formula (6), the orientation of any processing point of the optical element to be polished will be limited to a unified generatrix, greatly reducing the robot's range of motion. Moreover, the robot end effector only needs to adjust the orientation of the plane where the generatrix is ​​located, significantly reducing the range of robot stiffness variation.

[0054] In this optimization method, when the machining point is close to the C-axis rotation center, there is a problem of C-axis speed exceeding the limit. To address this issue, this application embodiment sets a C-axis speed threshold as a constraint condition. When entering the speed exceeding the limit region, under the premise of satisfying certain machining posture optimization, the robot motion becomes the main motion.

[0055] Specifically, when the machining point approaches the rotation center of the single-axis rotary table, causing the table speed to exceed a preset speed threshold, it is determined that the system has entered the speed over-limit region. The speed threshold is the highest safe speed allowed by the single-axis rotary table, which is a preset dynamic constraint condition of the system. The speed over-limit region is the area where the table needs to operate at excessive speed due to the machining point being close to the rotation center, requiring a switch in motion strategy. Within the speed over-limit region, the robot's motion becomes the primary motion, while the single-axis rotary table maintains a low-speed, uniform motion. Once the machining point leaves the speed over-limit region, the linkage mode reverts to one where the single-axis rotary table's motion is the primary motion and the robot's motion is secondary. The primary motion undertakes the main task of trajectory feeding, resulting in faster response and smoother movement. The secondary motion only performs minor compensation.

[0056] To achieve a smooth, shock-free transition between motion modes, this application further establishes a boundary transition point control strategy. Specifically, using a grating-type feed as the processing path, two control points are set on both sides of the optical element to be polished, one near the speed threshold and the other far from the speed threshold. The grating-type feed path is a typical optical element processing path with reciprocating feed in a single direction, suitable for polishing large-diameter planes. The two control points are translated along the feed direction of the processing path to form two boundary transition points. The control points are the critical positions where the speed on both sides of the optical element to be polished reaches the threshold, used to define the start and end positions of the over-limit area. Between the two boundary transition points, processing is performed using a combination of robot main motion and low-speed linkage of a single-axis rotary table. The boundary transition point is the switching position obtained after translating the control points along the feed direction, used to achieve a smooth transition between motion modes. When the robot crosses the second boundary transition point, it automatically switches back to the linkage mode of single-axis rotary table main motion, achieving a smooth, shock-free transition and avoiding processing marks.

[0057] Figure 4 This is a schematic diagram of robot-C-axis linkage path planning and constraint setting provided in one embodiment of this application. Taking the X-axis feed of the grating path as an example, this embodiment uses two points on both sides of the workpiece, one near and one far from the rotational speed threshold, as control points. The two control points are moved along the machining path in the positive X-axis direction to the corresponding boundary points. Since the C-axis joint angles corresponding to the two boundary points are close, and the path direction at this angle is similar to the machining generatrix direction of the robot, stopping the linkage between the two boundary points will not have a significant impact on the optimization target and effect. Therefore, the boundary points are used as two connection points. Between the connection points, the C-axis moves slowly and uniformly, with the robot movement as the main motion for linkage machining. After passing the second boundary point, the turntable movement becomes the main motion for linkage machining. Figure 5 This is a schematic diagram of the C-axis change curve before and after the linkage constraint between the robot and the C-axis, provided in one embodiment of this application. Figure 5 As shown, before constraint, the C-axis joint angle exhibits a significant jump in the central region, posing a risk of overspeed. After constraint, the C-axis joint angle changes smoothly without overspeed, while ensuring the continuity of machining.

[0058] Figure 6 This is a schematic diagram comparing the robot's path before and after C-axis linkage optimization, provided in one embodiment of this application. Figure 6 As shown, Figure 6The figure shows the robot's movement trajectory before and after using this embodiment. The dashed line represents the robot path before optimization, which is consistent with the planned relative processing path. The solid line represents the robot path after optimization. Compared to the unoptimized path, this path has a smaller coverage area and the processing direction is closer to the YZ plane, avoiding the problem of insufficient processing range in the X direction. This effectively improves the robot's processing range and dynamic response performance for large-diameter optical components and reduces stiffness fluctuations during robot processing.

[0059] The following example illustrates this further using a dual-axis oscillating stage as an additional axis. A dual-axis oscillating stage is a stage composed of two mutually perpendicular oscillating axes that can adjust the two-dimensional posture of the optical element to be polished. The two oscillating axes are typically perpendicularly orthogonal, allowing the normal direction of any machining point on the surface of the optical element to be polished to the target posture. This is suitable for polishing high-steepness, non-rotationally symmetric optical elements.

[0060] In step 103, the optical element to be polished can first be installed at the position of the common perpendicular line of the two axes of the dual-axis oscillating stage. The position of the common perpendicular line is the optimal installation position of the optical element to be polished, ensuring stable oscillation and accurate normal adjustment. This ensures that the optical element to be polished experiences uniform force and smooth posture changes during oscillation, guaranteeing the accuracy of the normal adjustment at the processing point. Next, based on the homogeneous coordinate transformation relationship in the multi-body kinematics model, the second target rotation angle of the dual-axis oscillating stage required for robot polishing is calculated. The second target rotation angle is the A-axis and B-axis oscillation angle calculated based on the homogeneous coordinate transformation relationship, used to adjust the external normal of the processing point to vertically upward. Then, the oscillation motion of the dual-axis oscillating stage is controlled, such as performing a compound oscillation motion according to the second target rotation angle, to drive the optical element to be polished to rotate, adjusting the external normal direction of any processing point on the surface of the optical element to vertically upward. This allows the polishing tool to press down vertically, ensuring uniform force and stable removal. Finally, the polishing tool is controlled to maintain a vertically downward posture, requiring no posture change, only performing small feed movements, cooperating with the dual-axis oscillating stage to complete the full-surface processing of the optical element to be polished.

[0061] Figure 7 This is a schematic diagram of a power-controlled polishing system combining a robot and a dual-axis oscillating worktable, provided in another embodiment of this application. Figure 7 As shown, assuming the dual-axis oscillating stage includes an A-axis and a B-axis, the robot-controlled polishing system linked with the dual-axis oscillating stage can include a robot 1, a polishing tool 2, an optical element to be polished 3, an A-axis 5, and a B-axis 6. The polishing tool 2 is mounted at the end of the robot, and the optical element to be polished 3 is fixedly mounted on the table surface of the dual-axis oscillating stage. The dual-axis oscillating stage achieves flexible adjustment of the workpiece posture through the combined oscillation of the A-axis 5 and the B-axis 6.

[0062] Figure 8 This is a schematic diagram of a multibody kinematics model with the AB axis as an additional axis, provided in another embodiment of this application. Figure 8 As shown, {O0} is the base coordinate system, which is established at the center point of the robot base. j} (1≤j≤6) represent the coordinate systems of the robot's six joints. {O t} is the tool coordinate system, and its Z-axis is... t Aligned with the tool axis direction. {O w} is the workpiece coordinate system, with its origin established at the center point of the workpiece's upper surface. A} is the A-axis coordinate system, {O B} is the origin of the B-axis coordinate system, X A Y B They coincide with the axes of A and B, respectively.

[0063] Based on the topological model, the homogeneous coordinate transformation relationships between the robot, AB turntable, tool, and workpiece coordinate systems can be obtained: (7) In formula (7), ,in, (1≤j≤6) represent the joint angles of robot 1. Based on the DH parameters of robot 1, this formula can be solved by standard calculation methods for forward and inverse kinematics. , Let A represent the spatial transformation relationship between the A-axis and the B-axis, and the workpiece coordinate system relative to the A-axis, respectively. Let the rotation angles of the two additional axes be the B-axis rotation angles. A-axis rotation angle Assuming the additional axes AB are perpendicularly orthogonally distributed, after rotating the additional axes AB, the normals of the machining points are transformed to be vertically upward, and the rotation transformation matrix in formula (8) is extracted to obtain: (8) At this point, the formula for calculating the rotation angle of the additional axis AB can be obtained: (9) (10) in, , , The three coordinate axis components of the unit normal vector of the workpiece surface at the optical processing point to be polished are the cosine of the Z-axis direction in formula (3). , , , The X-axis component of the normal vector. The Y-axis component of the normal vector. This is the Z-axis component of the normal vector.

[0064] When the AB axis moves according to formulas (9) and (10), the orientation of any processing point of the optical element to be polished will be limited to a uniform vertical normal, which greatly reduces the range of robot movement and the robot end does not need to adjust its orientation, thus significantly reducing the range of robot stiffness variation.

[0065] Figure 9 This is a schematic diagram comparing the robot path before and after optimization of the robot's linkage with the AB axis, provided in another embodiment of this application. Figure 9 As shown, before optimization, the robot needed to move extensively along a complex trajectory and constantly adjust its posture. After optimization, the robot only maintains a vertically downward posture with small movements, significantly reducing the path range while keeping the posture constant, resulting in a substantial improvement in processing stability. By using a dual-axis oscillation to adjust the normal of the processing point to vertically upward, the problem of poor posture and difficulty in processing high-steep optical components is solved. The robot maintains a fixed vertically downward posture throughout the process, without the need for extensive arm swinging or posture changes, remaining in a high-stiffness range with minimal stiffness fluctuations. The robot only performs small feed movements, significantly reducing the travel distance, resulting in higher positioning accuracy and faster dynamic response. All processing points are polished with the normal vertically upward and the tool vertically downward, resulting in uniform material removal and significantly improved surface quality and surface shape accuracy. The dual-axis oscillating worktable eliminates the problem of a sudden increase in the rotational center speed, ensuring smooth and continuous processing without the need to switch between primary and auxiliary motions, making the system more stable.

[0066] In step 104, during the entire polishing process of the robot moving along the target processing path, the polishing force is detected in real time by the end effector. The end effector, installed between the robot's end effector and the polishing tool, is a closed-loop actuator used to detect the polishing contact force in real time and dynamically adjust the axial feed pressure; it is the core component for achieving constant force polishing. The polishing force detected in real time is the actual contact force between the polishing tool and the workpiece surface, collected in real time by the end effector during processing.

[0067] The real-time polishing force is compared with the preset polishing force to determine the polishing force fluctuation. The preset polishing force is a target polishing pressure value pre-set according to the optical component material and polishing process requirements, providing a benchmark for constant force control. The polishing force fluctuation is the difference between the real-time polishing force and the preset polishing force, reflecting the degree to which the polishing force deviates from the target value. Then, based on the polishing force fluctuation, the axial feed downward pressure of the polishing tool is adjusted in real time. The axial feed downward pressure is the feed displacement of the polishing tool along its own axis, used to directly adjust the contact pressure.

[0068] Finally, compensation is provided for the polishing force deviation caused by robot positioning errors, joint stiffness deformation, and changes in processing posture. The polishing force deviation is caused by non-process factors such as robot positioning errors, joint deformation, and posture changes, resulting in unstable polishing force. This ensures that the polishing force remains constant throughout the polishing process. In other words, the actual polishing force remains stable near the preset value throughout the entire polishing process, and fluctuations are suppressed within the allowable range.

[0069] By compensating for force deviations caused by robot positioning errors, joint deformation, and posture changes in real time, constant-force stable polishing can be achieved, resulting in more uniform material removal and reducing surface scratches, local over-polishing, or under-polishing caused by fluctuating pressure. This significantly improves surface roughness and surface accuracy. Furthermore, it reduces the reliance on the robot's absolute positioning accuracy, allowing the robot to operate within its optimal posture range, balancing stiffness, stability, and machining accuracy. This meets the stringent requirements of large-diameter, high-steepness optical components for polishing force stability, improving yield and processing consistency.

[0070] Figure 10 This is a schematic diagram of the structure of a multi-axis dynamic control polishing device for robotic optical elements provided in an embodiment of this application. Figure 10 As shown, the multi-axis dynamic control polishing device 1000 for robot optical components may include a construction module 1001, an optimization module 1002, an adjustment module 1003, and a compensation module 1004.

[0071] The construction module 1001 is used to construct a multibody kinematic model of the robot, the additional axis and the optical element to be polished, establish the homogeneous coordinate transformation relationship between the base coordinate system, the tool coordinate system, the workpiece coordinate system and the additional axis coordinate system, and determine the position and normal information of each machining point on the initial machining path.

[0072] The optimization module 1002 is used to perform global pose matching optimization on the initial machining path with the joint combination of the robot and the additional axis as the motion allocation variable, with the optimization objectives of expanding the machining range, improving the system stiffness and dynamic response characteristics, and with the joint limits and motion speed limits of the robot and the additional axis as constraints, to obtain the target machining path.

[0073] The adjustment module 1003 is used to adjust the workpiece posture of the optical element to be polished through the worktable of the additional axis according to the pose and motion parameters of each processing point under the target processing path, so that the robot's polishing tool and the processing point maintain a preset fixed relative posture.

[0074] The compensation module 1004 is used to continuously polish the surface of the optical element to be polished along the target processing path, and to compensate for the fluctuation of polishing force in real time through the end force control mechanism of the polishing tool during the polishing process.

[0075] Among them, the construction module 1001, optimization module 1002, adjustment module 1003 and compensation module 1004 can be used to execute steps 101-104 in the embodiments of the above-mentioned multi-axis dynamic control polishing method for robot optical elements. For the specific implementation of these modules and more details, please refer to the corresponding method section, which will not be elaborated here.

[0076] This application also provides a computer-readable storage medium storing a program that can be loaded by a processor and executed by any of the multi-axis dynamic control polishing methods for robot optical elements in this application.

[0077] Those skilled in the art will understand that all or part of the functions of the various methods in the above embodiments can be implemented by hardware or by computer programs. When all or part of the functions in the above embodiments are implemented by computer programs, the program can be stored in a computer-readable storage medium, which may include: read-only memory, random access memory, disk, optical disk, hard disk, etc., and the program is executed by a computer to achieve the above functions. For example, the program can be stored in the memory of a device, and when the program in the memory is executed by the processor, all or part of the above functions can be achieved. In addition, when all or part of the functions in the above embodiments are implemented by computer programs, the program can also be stored in a server, another computer, disk, optical disk, flash drive, or external hard drive, etc., and can be downloaded or copied to the memory of a local device, or the system of the local device can be updated. When the program in the memory is executed by the processor, all or part of the functions in the above embodiments can be achieved.

[0078] The above examples illustrate this application only to aid understanding and are not intended to limit its scope. Those skilled in the art to which this application pertains can make various simple deductions, modifications, or substitutions based on the ideas presented.

Claims

1. A multi-axis dynamic controlled polishing method for robotic optical components, characterized in that, include: Construct a multibody kinematics model of the robot, the additional axis, and the optical element to be polished; establish the homogeneous coordinate transformation relationship between the base coordinate system, the tool coordinate system, the workpiece coordinate system, and the additional axis coordinate system; and determine the position and normal information of each machining point on the initial machining path. Using the joint combination of the robot and the additional axis as motion allocation variables, with the optimization objectives of expanding the processing range and improving the system stiffness and dynamic response characteristics, and with the joint limits and motion speed limits of the robot and the additional axis as constraints, global pose matching optimization is performed on the initial processing path to obtain the target processing path; Based on the pose and motion parameters of each processing point under the target processing path, the workpiece posture of the optical element to be polished is adjusted by the worktable of the additional axis, so that the polishing tool of the robot and the processing point maintain a preset fixed relative posture. The surface of the optical element to be polished is continuously polished along the target processing path, and the polishing force fluctuation is compensated in real time by the end force control mechanism of the polishing tool during the polishing process.

2. The multi-axis dynamic controlled polishing method for robot optical elements according to claim 1, characterized in that, The process involves constructing a multibody kinematic model of the robot, the additional axis, and the optical element to be polished; establishing homogeneous coordinate transformation relationships between the base coordinate system, tool coordinate system, workpiece coordinate system, and additional axis coordinate system; and determining the position and normal information of each machining point on the initial machining path, including: A base coordinate system is established at the center point of the robot's base, a workpiece coordinate system is established at the center point of the upper surface of the optical element to be polished, and a tool coordinate system is established at the end of the polishing tool, and the workpiece coordinate system is aligned with the direction of the base coordinate system. The pose calibration of the additional axis and the optical element to be polished is performed to obtain the homogeneous coordinate transformation relationship between the base coordinate system, the tool coordinate system, the workpiece coordinate system and the additional axis coordinate system, thereby obtaining the multibody kinematics model; The initial machining path and machining points are planned in the workpiece coordinate system, and the pose parameters of each machining point on the initial machining path are determined according to the position of each machining point and the surface normal.

3. The multi-axis dynamic controlled polishing method for robot optical elements according to claim 1, characterized in that, The initial machining path is optimized by global pose matching, using the joint combination of the robot and the additional axis as motion allocation variables, with the optimization objectives of expanding the machining range and improving system stiffness and dynamic response characteristics, and with the joint limits and motion speed limits of the robot and the additional axis as constraints, to obtain the target machining path, including: Using the joint combination of the robot and the additional axis as the motion assignment variable, the pose of each processing point is solved based on the multibody kinematics model; The optical element to be polished is moved by the additional axis so that the processing points all fall within the effective working space of the robot, which is the first optimization objective. Constraining the range of motion of the robot's joints to maintain the robot in a high-stiffness posture range is the second optimization objective; Using the additional axis to bear the main motion component of the trajectory feed, thereby reducing the robot's following error, is the third optimization objective; The first optimization objective, the second optimization objective, and the third optimization objective are taken as a joint optimization objective; The angular limits and motion speed limits of each joint of the robot, and the rotational limits and speed limits of the additional axes are used as constraints. The robot joint angles and additional axis joint angles corresponding to all machining points on the initial machining path are uniformly calculated and globally matched to select the optimal motion combination that satisfies all constraints, thereby obtaining the target machining path.

4. The multi-axis dynamic controlled polishing method for robot optical elements according to claim 1, characterized in that, The additional axis is a single-axis rotary table; The step of adjusting the workpiece posture of the optical element to be polished via the worktable of the additional axis, so that the polishing tool and the processing point maintain a preset fixed relative posture, includes: The optical element to be polished is mounted on the rotation center line of the single-axis rotary table, so that the axis of the workpiece coordinate system coincides with the axis of the additional axis coordinate system. The first target rotation angle of the single-axis rotary table is calculated based on the homogeneous coordinate transformation relationship. The single-axis rotary table is controlled to rotate around its own axis, driving the optical element to be polished to rotate, so that any processing point on the surface of the optical element to be polished enters the preset fixed processing generatrix in sequence. The robot is controlled to move only along the fixed machining line, and in conjunction with the rotation of the single-axis rotary table, the entire surface of the optical element to be polished is processed.

5. The multi-axis dynamic controlled polishing method for robot optical elements according to claim 4, characterized in that, Also includes: When the processing point is close to the rotation center of the single-axis rotary table, causing the table speed to exceed the preset speed threshold, it is determined that the speed exceeds the limit. Within the speed limit range, the robot's motion is the main motion, while the single-axis rotary table maintains a low-speed uniform motion. Once the processing point leaves the speed limit area, the linkage mode is restored, with the single-axis rotary table as the main motion and the robot as the auxiliary motion.

6. The multi-axis dynamic controlled polishing method for robot optical elements according to claim 5, characterized in that, Also includes: Using grating-type feed as the processing path, two control points are set on both sides of the optical element to be polished, one near the rotational speed threshold and the other away from the rotational speed threshold. The two control points are translated along the feed direction of the machining path to form two boundary connection points; The machining is performed between the two boundary connection points using the robot's main motion and the low-speed linkage of the single-axis rotary table. After the robot crosses the second boundary connection point, it automatically switches back to the linkage mode of the single-axis rotary table main motion.

7. The multi-axis dynamic controlled polishing method for robot optical elements according to claim 1, characterized in that, The additional axis is a dual-axis swing table; The step of adjusting the workpiece posture of the optical element to be polished via the worktable of the additional axis, so that the polishing tool and the processing point maintain a preset fixed relative posture, includes: The optical element to be polished is mounted at the position of the common perpendicular line of the two axes of the dual-axis oscillating worktable; The second target rotation angle of the dual-axis oscillating worktable is calculated based on the homogeneous coordinate transformation relationship. The oscillation motion of the dual-axis oscillating worktable is controlled to drive the optical element to be polished to rotate, so that the outward normal direction of any processing point on the surface of the optical element to be polished is adjusted to vertically upward. The polishing tool is controlled to maintain a vertically downward posture, and works in conjunction with the dual-axis swing table to complete the full-surface processing of the optical element to be polished.

8. The multi-axis dynamic controlled polishing method for robot optical elements according to claim 1, characterized in that, The continuous polishing of the surface of the optical element to be polished along the target processing path, and the real-time compensation of polishing force fluctuations through the end force control mechanism of the polishing tool during the polishing process, includes: Throughout the entire polishing process, the polishing force is detected in real time by the end force control mechanism. The real-time polishing force is compared with the preset polishing force to determine the amount of polishing force fluctuation. The axial feed downward pressure of the polishing tool is adjusted in real time according to the polishing force fluctuation. It compensates for the polishing force deviation caused by robot positioning errors, joint stiffness deformation and changes in processing posture, so as to keep the polishing force constant during the polishing process.

9. A multi-axis dynamic control polishing device for robotic optical elements, characterized in that, include: The construction module is used to build a multibody kinematics model of the robot, the additional axis, and the optical element to be polished, establish the homogeneous coordinate transformation relationship between the base coordinate system, the tool coordinate system, the workpiece coordinate system, and the additional axis coordinate system, and determine the position and normal information of each machining point on the initial machining path. The optimization module is used to perform global pose matching optimization on the initial machining path, with the joint combination of the robot and the additional axis as the motion allocation variable, and with the optimization objectives of expanding the machining range and improving the system stiffness and dynamic response characteristics, and with the joint limits and motion speed limits of the robot and the additional axis as constraints, to obtain the target machining path. The adjustment module is used to adjust the workpiece posture of the optical element to be polished through the worktable of the additional axis according to the pose and motion parameters of each processing point under the target processing path, so that the polishing tool of the robot and the processing point maintain a preset fixed relative posture. The compensation module is used to continuously polish the surface of the optical element to be polished along the target processing path, and to compensate for the fluctuation of polishing force in real time through the end force control mechanism of the polishing tool during the polishing process.

10. A computer-readable storage medium, characterized in that, The computer-readable storage medium stores a program that can be loaded by a processor and executed as described in any one of claims 1 to 8, a multi-axis coupled dynamic control polishing method for robotic optical elements.

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