Optical element robot tail end multi-module force control polishing device

Abstract

The invention belongs to the technical field of robot polishing, and discloses a multi-module force control polishing device at the tail end of an optical element robot, and the force control execution response precision and speed of the multi-module force control polishing device break through the traditional limitation. Millisecond-level dynamic response and submicron-level force control precision are achieved through direct driving, the response bandwidth and pressure stability in the high-frequency dynamic machining process are remarkably improved, and the problems that force control of a traditional rigid structure is delayed and overshoot is likely to happen are solved. A high-rigidity multi-guide-rail structure is used for improving the structural stability and the anti-interference capability: the multi-guide-rail high-rigidity structure is formed by designing a double nested supporting mode of a gravity balance guide rail and a linear slide rail, so that the force control module still has excellent anti-interference capability under a vibration excitation working condition; the problem that additional vibration is generated due to the fact that the structure of a traditional device is easily stimulated in the conformal vibration machining process is solved.

Description

TECHNICAL FIELD

[0001] The application belongs to the technical field of robot polishing, and particularly relates to a multi-module force control polishing device for the end of a robot for optical elements. BACKGROUND

[0002] As a core component of precision instruments, the surface quality of an optical element directly determines the imaging precision and energy transmission efficiency of an optical system. With the development of new-generation optical systems towards large aperture, asphericity and miniaturization, higher requirements are put forward for the polishing precision of optical elements. Traditional robot polishing utilizes pneumatic or mechanical polishing technology, which is difficult to meet the force control precision requirements of high-precision polishing of optical elements. At the same time, with the deepening of the research on the improvement of the surface quality of optical elements by conformal vibration polishing process, the demand for using conformal vibration polishing to improve the surface quality of optical elements is further improved. Therefore, it is necessary to develop a force control device suitable for both small polishing head polishing and conformal vibration polishing to realize high surface precision and quality of optical elements. At present, the defects of the existing force control polishing technology are as follows:

[0003] Through the above analysis, the problems and defects of the existing technology are:

[0004] (1) The existing polishing pneumatic or mechanical force control actuator has low force control precision: traditional polishing equipment generally adopts a rigid actuator of "servo motor + ball screw" or direct driving by pneumatic pressure, which has low dynamic response bandwidth and is difficult to adapt to high-frequency vibration polishing or high-speed rotation working conditions. This makes the pressure fluctuation of the optical element polishing larger, and the surface shape precision of the optical element polishing difficult to converge.

[0005] (2) The existing device is usually compatible only with small polishing head polishing: most existing polishing systems use a small polishing head as the core single machining mode, and rely on the rotation of the small polishing head to realize material removal. Although this method has certain advantages in repairing low-frequency surface errors, it has low overall removal efficiency and is easy to cause medium-frequency errors in the machined optical elements due to the small removal area and high repeatability of the trajectory. At the same time, the current device generally lacks compatibility with conformal vibration polishing process. Conformal vibration polishing is an advanced machining method that maintains flexible contact between the polishing tool and the workpiece surface and superimposes high-frequency small-amplitude or low-frequency large-amplitude vibration, which can significantly improve the adaptive machining capability of complex curved surface regions. This process puts higher requirements on the dynamic response, vibration coupling and force control stability of the actuator, and the traditional device does not have compatible conditions in terms of structural design and actuator configuration, making it difficult to realize the organic integration of small polishing head fine machining and conformal vibration flexible polishing, thereby limiting its applicability in various complex curved surface scenarios.

[0006] (3) The eccentricity of the small grinding head polishing planet wheel is difficult to adjust: the traditional single motor driven planetary polishing mechanism adopts a fixed eccentric structure design, that is, the small grinding head rotates around its own shaft while rotating around the main shaft with a fixed eccentricity to realize compound trajectory motion. Although this structure can improve the material removal effect to a certain extent, the fixed eccentricity design limits the adaptability to different optical element surface topography and material characteristics. In actual polishing process, different curvature radius, material hardness or removal amount requirements often require different eccentric parameters to optimize the trajectory distribution and removal function. The fixed eccentric structure cannot meet the flexible adjustment requirements of diversified processing tasks, resulting in insufficient coverage of the processing area, high trajectory repetition, easy introduction of medium frequency error or local polishing deficiency, thereby affecting the final surface precision and processing efficiency. At the same time, the fixed eccentricity is not conducive to the cooperation with other process modules such as conformal vibration, limiting the universality of the device and the potential of improving the processing quality.

[0007] (4) The stability of the force control actuator body is poor under the processing technology of common vibration and the like: in the process of conformal vibration polishing and the like, in order to realize the self-adaptive matching with the free curved surface contact surface, the polishing end part is often excited with vibration of a certain frequency and amplitude. However, the traditional force control actuator has insufficient structural rigidity or poor damping characteristics, and when subjected to frequent disturbance excitation, the body structure is prone to produce unwanted additional vibration, resulting in distortion or drift of the force control signal, and then affecting the stability of the force control system and the consistency of the polishing effect. Especially in the low-frequency large-amplitude vibration mode, the structural dynamic characteristics of the actuator itself become the key factor restricting the stable operation of the system.

[0008] (5) The gravity load of the force control end causes poor force control stability: with the development of multifunctional polishing end structure (such as integrated small grinding head, vibration module, etc.), the weight of the end load is increasing, so that the force control actuator needs to bear the gravity component in the vertical direction, causing the system to be in a non-zero steady-state bias force state for a long time, which seriously affects the force control accuracy and dynamic response. Especially in the fine polishing stage with strict requirements for weak contact force or micro-removal depth, the force control fluctuation caused by the end gravity will directly cause the nonlinear change of the polishing force, resulting in processing defects. The traditional device lacks effective active or passive adjustable gravity compensation mechanism, and it is difficult to ensure the stability and repeatability of the force control in the processing process.

[0009] Therefore, how to develop a force control device suitable for small grinding head polishing and conformal vibration polishing at the same time, and realize the rapid switching of various high-precision force control polishing methods and processes is the key and difficulty to solve the problem. SUMMARY

[0010] In view of the problems existing in the prior art, the present application provides a robot end multi-module force control polishing device for optical elements.

[0011] The application is achieved by a robot end multi-module force control polishing device for optical elements, which comprises:

[0012] The force control module of the voice coil motor with gravity balance, the planetary polishing mechanism module, the low-frequency macro-vibration module, and the high-frequency micro-vibration module.

[0013] The force control module of the voice coil motor with gravity balance is composed of a mover and a stator, and comprises a gravity balance module support, a gravity balance cylinder, a gravity balance guide rail, a module connecting piece, an overall frame connecting piece, a voice coil motor stator, an overall frame side support plate, a voice coil motor mover, a mover slider connecting piece, a mover force sensor connecting plate, a force sensor, a linear slide rail, and a linear slider.

[0014] The mover of the force control module of the voice coil motor with gravity balance comprises the gravity balance cylinder, the module connecting piece, the voice coil motor mover, the mover slider connecting piece, the mover force sensor connecting plate, the force sensor, and the linear slider.

[0015] The stator of the force control module of the voice coil motor with gravity balance comprises the gravity balance module support, the gravity balance guide rail, the overall frame connecting piece, the voice coil motor stator, the overall frame side support plate, the linear slide rail, and the encapsulation support plate.

[0016] The force control module of the voice coil motor with gravity balance can be connected to the planetary polishing mechanism module, the low-frequency macro-vibration module, and the high-frequency micro-vibration module in a modular manner to realize rapid debugging and switching of various processes.

[0017] Further, the gravity balance cylinder has two symmetrical distributions on the left and right sides, and the gravity balance guide rail has four symmetrical distributions on the left and right sides.

[0018] The linear slide rail has two symmetrical distributions on the left and right sides, and the linear slider has two symmetrical distributions on the left and right sides.

[0019] Further, the gravity balance cylinder and the gravity balance guide rail are located on the outside of the overall frame connecting piece, and the linear slide rail and the linear slider are located on the inside of the overall frame connecting piece.

[0020] Further, the module connecting piece, the overall frame connecting piece, and the mover slider connecting piece are designed in a U shape, the module connecting piece is connected to the mover slider connecting piece via the mover force sensor connecting plate and the force sensor, the overall frame connecting piece is embedded in the module connecting piece and can slide along the four gravity balance guide rails, the mover slider connecting piece is embedded in the overall frame connecting piece and can slide along the two linear slide rails, and the rigidity of the force control module is improved through the cross-embedded sliding mode.

[0021] The mover can generate single degree of freedom movement along the four gravity balance guide rails and the two linear guide rails, and the gravity balance guide rails and the two linear guide rails are distributed on the left and right sides, so that the high anti-vibration characteristics are achieved in the movement direction.

[0022] Further, the gravity balance cylinder can adjust the supporting pressure through the air pressure adjustment pneumatic circuit, and the adjustable constant gravity compensation can be achieved when the pressure is adjusted to be consistent with the gravity; the active adjustable gravity compensation can be further achieved through the active air pressure control circuit.

[0023] Further, the mover force sensor connecting plate connects the force sensor from top to bottom, the force sensor connects the module connecting piece from top to bottom, the module connecting piece is connected with the gravity balance cylinder, and the compensation effect is directly applied to the module connecting piece, so that the feedback value of the force sensor is the resultant force of the module connecting piece, thereby realizing that the feedback value of the force sensor is the reading after gravity compensation.

[0024] Further, the voice coil motor stator is embedded with a ring-shaped magnet, the voice coil motor mover is composed of a packaged ring-shaped coil, and the voice coil motor mover generates electromagnetic force after passing through current and generating a magnetic field with the voice coil motor stator magnet, to drive the mover to move;

[0025] The planetary polishing mechanism module is designed symmetrically from top to bottom, and the module connecting piece of the voice coil motor force control module with gravity balance can be connected with the planetary polishing mechanism module to ensure that the force direction passes through the center of the planetary polishing mechanism module.

[0026] The planetary polishing mechanism module mainly includes, from top to bottom, a force control-planetary connecting plate, a planetary servo motor, a planetary servo motor support plate, a planetary mechanism, an eccentricity adjustment quick support plate, an eccentricity adjustment quick connector, and a small grinding head.

[0027] The force control-planetary connecting plate is connected with the planetary servo motor support plate, so as to facilitate quick connection of the planetary polishing mechanism with the module connecting piece of the voice coil motor force control module with gravity balance.

[0028] Further, the planetary mechanism is connected through the planetary servo motor support plate, so as to keep the inner ring gear in the planetary mechanism fixed.

[0029] Further, the servo motor directly drives the sun gear in the planetary mechanism through the output shaft, and the inner ring gear in the mechanism is fixed, so as to drive the planetary gear in the planetary mechanism to generate planetary motion.

[0030] The small grinding head is connected with the output shaft of the planetary gear in the planetary mechanism, so as to realize the planetary motion of the small grinding head acting on the polishing of the optical element.

[0031] In order to obtain the eccentricity adjustable planetary polishing mechanism, the universal eccentricity adjustment quick connector is provided for the planetary polishing mechanism, the universal eccentricity adjustment quick connector is connected with the planetary polishing mechanism through the eccentricity adjustment quick support plate, and is connected with the double planetary wheel output shaft of the planetary mechanism through the bearing, so that the transmission of the planetary mechanism is realized.

[0032] The eccentricity adjustment module is provided to meet the requirements of the planetary polishing mechanism for different eccentricity. The eccentricity adjustment module can be set according to the different eccentricity requirements, and the different eccentricity can be realized by the different distance between the output hole and the center of the module.

[0033] The eccentricity adjustment module is connected with the universal eccentricity adjustment quick connector provided for the planetary polishing mechanism through threads, and the eccentricity of the planetary polishing mechanism can be quickly adjusted by replacing the eccentricity adjustment module with different holes.

[0034] The input shaft and the output shaft of the eccentricity adjustment module are connected through multi-stage gear transmission, and the input shaft is the output shaft of the planetary mechanism, so that the motion information of the planetary mechanism is transmitted.

[0035] When the planet polishing mechanism module is connected to the voice coil motor force control module with gravity balance, the motion of the planet polishing mechanism module is driven when the mover of the voice coil motor force control module with gravity balance moves, and the contact pressure is generated when the optical element is contacted, and the gravity of the optical element is compensated by the voice coil motor force control module with gravity balance.

[0036] The low-frequency macro-vibration module mainly comprises a force control macro-vibration connector, an optical rod slide rail, a linear bearing, a conformal grinding head, a macro-vibration linear slide rail, a macro-vibration linear slide block, a macro-vibration voice coil motor mover, and a macro-vibration voice coil motor stator.

[0037] The low-frequency macro-vibration module is connected to the voice coil motor force control module with gravity balance through the module connector and the force control macro-vibration connector.

[0038] The optical rod slide rail and the linear bearing of the low-frequency macro-vibration module form a main sliding pair, the macro-vibration linear slide rail and the macro-vibration linear slide block form a secondary sliding pair, and the main and secondary sliding pair structure can further improve the structural rigidity and vibration reliability.

[0039] The macro-vibration voice coil motor mover moves under the electromagnetic interaction current input of the macro-vibration voice coil motor stator, the low-frequency macro-vibration module generates a low-frequency millimeter-level amplitude motion less than 50Hz along the main and secondary sliding pairs, and the macro-vibration conformal grinding head acts on the optical element.

[0040] The high-frequency micro-vibration module mainly comprises a connection main clamp, a connection secondary clamp, a piezoelectric vibration unit, and a micro-vibration conformal grinding head, and realizes a micron-level motion greater than 50Hz.

[0041] The high-frequency micro-vibration module is connected with the module connecting piece, and the main clamp and the secondary clamp of the high-frequency micro-vibration module form a double-point installation layout to enhance the fixing strength of the piezoelectric vibration unit.

[0042] The micro-vibration conformal grinding head is connected with the piezoelectric vibration unit, the axis position of the micro-vibration conformal grinding head is consistent with the force control center position, so that the contact pressure during processing is stable.

[0043] The module connecting piece can be connected with other modules, and the process replacement of multiple modules can be realized.

[0044] Another object of the present application is to provide a multi-module force control polishing device method for an optical element robot end, comprising:

[0045] Step one, using a voice coil module to generate a direct drive force, which is flexible rather than rigid;

[0046] Step two, build a gravity compensation structure, use a gas cylinder to generate a pneumatic compensation force to realize the gravity compensation of the end module.

[0047] Step three, build a multi-module force control device structure, realize the quick switching and compatible integration of multiple processing modes;

[0048] Step four, realize high-precision force control accurate control through force sensor feedback combined with the control system, and monitor and control the force and displacement by using the sensor system;

[0049] Step five, according to different process requirements, use small grinding head planetary polishing or conformal vibration polishing to realize high-efficiency and high-precision material removal, so as to obtain optical elements with high surface precision and quality;

[0050] Step six, through the structure design, effectively integrate the overall structure of the device, ensure the function, stability and high rigidity of the device, and effectively reduce the volume.

[0051] In combination with the above technical solutions and the technical problems solved, the technical solutions to be protected by the present application have the following advantages and positive effects:

[0052] First, the force control execution response precision and speed break through the traditional limit: the present application uses a voice coil motor to replace the traditional ''servo motor + ball screw'' structure, directly drives to realize millisecond-level dynamic response and sub-micron-level force control precision, significantly improves the response bandwidth and pressure stability in the high-frequency dynamic processing process, and solves the problems of force control delay and easy overshoot of the traditional rigid structure.

[0053] High-rigidity multi-guide rail structure improves structural stability and anti-interference capability: By designing the double-nested support mode of gravity balance guide rail and linear slide rail, a multi-guide rail high-rigidity structure is formed, so that the force control module still has excellent anti-interference capability under vibration excitation working condition, overcoming the problem that the traditional device is easily excited and additional vibration is generated in conformal vibration machining.

[0054] Multi-mode modular polishing system improves process adaptability and machining efficiency: The planetary small polishing head polishing module, low-frequency macro-vibration module and high-frequency micro-vibration module are innovatively integrated, and are quickly assembled and disassembled and switched through the standardized module interface, so that the polishing system can adapt to the correction requirements of various complex curved surfaces and different frequency errors, and realize the integration of rough polishing, fine polishing and micro-polishing.

[0055] Adjustable planetary eccentric distance structure: A novel adjustable eccentric distance small polishing head polishing structure is innovatively designed, the fast connection mechanism is used to adjust the eccentric distance of the small polishing head relative to the main rotating shaft, so that the small polishing head can be flexibly adapted to the polishing tasks of optical elements with different sizes, different curvature radii and different removal requirements.

[0056] Self-adaptive gravity compensation function is provided to ensure the stability in weak force machining stage: The pneumatic gravity compensation system is introduced and integrated with the force sensor, so that the dynamic compensation of the end load is realized, the system always maintains the near-zero static bias force state, the weak contact force control capability is significantly improved, and the system is particularly suitable for high-precision micro-removal machining.

[0057] Flexible contact and high-efficiency removal are considered, and the polishing of complex free curved surface is adapted: Through the conformal polishing head and the dual-vibration excitation mode of voice coil / piezoelectricity, the system can apply high-frequency or low-frequency vibration on the basis of maintaining flexible contact, and the machining adaptability of the device in the complex surface area with large curvature and high slope is effectively expanded.

[0058] Modular structure design reduces maintenance cost, improves equipment universality and expandability: The standard module structure is used in the whole device, each functional unit can be independently disassembled, maintained or upgraded according to the process requirement, a good compatible basis is provided for different robot platforms and multi-category optical element machining, and the application scenarios are widened.

[0059] The technical scheme of the present application fills the technical blank in the industry at home and abroad: At present, there is no mature scheme that can realize the integrated optical element polishing capability of "high-frequency force control + multi-mode polishing + flexible contact + module switching" at the end of the robot. The voice coil motor and the pneumatic gravity compensation system are innovatively combined, and the detachable multi-module structure and the dual-channel (low-frequency and high-frequency) excitation mode are innovatively introduced, the bottlenecks of the traditional force control device, such as poor structural rigidity, slow feedback response and narrow process adaptation range, are broken, and the present application is the first to be proposed and realized at home and abroad, which fills the technical blank of the high-performance robot end flexible actuator in the field of complex optical machining.

[0060] The technical scheme of the present application solves the technical problems that people have been eager to solve but have always failed to succeed, specifically including the following points:

[0061] (1) Force control response lag and insufficient precision problem: Through the direct force control structure of the voice coil drive, high response and high precision active normal force regulation is realized, avoiding the problems of slow response and control hysteresis of traditional structures.

[0062] (2) Vibration interference problem caused by poor structural rigidity during processing: A multi-guide rail high rigidity structure design is adopted, and the influence of external vibration on system stability is reduced through mechanical vibration isolation and pneumatic support.

[0063] (3) Multi-process adaptation problem of different error frequency surfaces: A multi-module system capable of rapid switching is introduced to cope with micro-high frequency errors (high frequency micro-vibration module), macro-low frequency errors (low frequency macro-vibration module) and overall topography correction (planetary polishing mechanism module), while the adjustable planetary polishing mechanism module is combined to realize targeted repair of different scale errors.

[0064] (4) Poor processing stability of complex curved surfaces and edge regions: A conformal grinding head with compliant contact characteristics is designed, and a force control system with active adjustment is used to ensure the processing stability and removal uniformity of complex slope regions.

[0065] (5) Unstable control problem in weak contact polishing stage: With the help of pneumatic gravity compensation and force sensor feedback, sub-Newton level weak force stable output is realized, which adapts to the precision machining requirements of super-smooth and extremely small removal amount. BRIEF DESCRIPTION OF DRAWINGS

[0066] Figure 1 is the A-A cross-sectional view of the optical element robot end multi-module force control polishing device provided by the embodiment of the present application.

[0067] Figure 2 is the B-B cross-sectional view of the optical element robot end multi-module force control polishing device provided by the embodiment of the present application.

[0068] Figure 3 is the top view of the optical element robot end multi-module force control polishing device provided by the embodiment of the present application.

[0069] Figure 4 is the schematic diagram of the voice coil motor force control module with gravity balance connecting the planetary polishing mechanism module provided by the embodiment of the present application.

[0070] Figure 5 is the schematic diagram of the eccentricity adjustment module equipped with the planetary polishing mechanism provided by the embodiment of the present application.

[0071] Figure 6It is the low frequency macro vibration module schematic diagram of the voice coil motor force control module with gravity balance provided by the embodiment of the application.

[0072] Figure 7 It is the high frequency micro vibration module schematic diagram of the voice coil motor force control module with gravity balance provided by the embodiment of the application.

[0073] Figure 8 It is the optical element effect schematic diagram provided by the embodiment of the application.

[0074] Figure 9 It is the optical element robot end multi-module force control polishing device method flow chart provided by the embodiment of the application.

[0075] Figure 10 It is the implementation sample diagram provided by the embodiment of the application.

[0076] Figure 11 It is the device integrated voice coil motor vibration unit or piezoelectric vibration unit diagram provided by the embodiment of the application. DETAILED DESCRIPTION

[0077] In order to make the purpose, technical scheme and advantages of the application more clear, the application is further described in detail below in combination with embodiments. It should be understood that the specific embodiments described herein are only used to explain the application and do not limit the application.

[0078] The core of the technical scheme of the application is to develop a robot end multi-module optical element force control polishing device, and the necessary technical features include: a voice coil motor force control module with gravity balance, which is used to realize high-bandwidth, adjustable gravity compensation and precise force control; a planetary polishing mechanism module, which is used to realize small polishing head optical element polishing; a low frequency macro vibration module and a high frequency micro vibration module, which are respectively used for conformal vibration polishing under different process requirements. This comprehensive technical feature makes the actuator flexible, efficient and adaptable in the field of robot polishing technology.

[0079] As shown in Figure 1 The voice coil motor force control module with gravity balance is composed of a mover and a stator, including a gravity balance module support 101, a gravity balance cylinder 102, a gravity balance guide rail 103, a module connecting piece 104, an overall frame connecting piece 105, a voice coil motor stator 106, an overall frame side support plate 107, a voice coil motor mover 108, a mover sliding block connecting piece 109, a mover force sensor connecting plate 110, a force sensor 111, a linear sliding rail 112, a linear sliding block 113 and an encapsulation support plate 114.

[0080] As shown in Figure 2As shown, the mover of the gravity-balanced voice coil motor force control module includes: a gravity-balanced cylinder 102, a module connector 104, a voice coil motor mover 108, a mover slider connector 109, a mover force sensor connector 110, a force sensor 111, and a linear slider 113.

[0081] like Figure 3 As shown, the stator of the force control module for a voice coil motor with gravity balance includes: a gravity balance module support 101, a gravity balance guide rail 103, an integral frame connector 105, a voice coil motor stator 106, an integral frame side support plate 107, a linear slide rail 112, and an encapsulation support plate 114.

[0082] The gravity-balanced voice coil motor force control module can be modularly connected with the planetary polishing mechanism module, the low-frequency macro vibration module, and the high-frequency micro vibration module to achieve rapid debugging and switching of various processes.

[0083] The gravity balance cylinder 102 has two cylinders symmetrically distributed on the left and right sides, and the gravity balance guide rail 103 has four cylinders symmetrically distributed on the left and right sides.

[0084] The linear slide rails 112 are two in number and symmetrically distributed on the left and right sides, and the linear sliders 113 are two in number and symmetrically distributed on the left and right sides. The gravity balance cylinder 102 and the gravity balance guide rail 103 are located outside the overall frame connector 105, while the linear slide rails 112 and the linear sliders 113 are located inside the overall frame connector 105. The module connector 104, the overall frame connector 105, and the mover slider connector 109 are all U-shaped designs. The module connector 104 is connected to the mover slider connector 109 via the mover force sensor connecting plate 110 and the force sensor 111. The overall frame connector 105 is embedded in the module connector 104 and can slide along the four gravity balance guide rails 103. The mover slider connector 109 is embedded in the overall frame connector 105 and can slide along the two linear slide rails 112. The rigidity of the force control module is improved by the cross-embedded sliding method. The mover can generate single-degree-of-freedom motion along four gravity balance guide rails 103 and two linear slide rails 112. Since the gravity balance guide rails 103 and the two linear slide rails 112 are all located on the left and right sides, it has high vibration resistance in this motion direction.

[0085] The gravity balance cylinder 102 can adjust the supporting pressure through the air pressure adjustment pneumatic circuit, and the adjustable constant gravity compensation can be achieved when the pressure is adjusted to be consistent with the gravity; the active gravity compensation can be further achieved through the active air pressure control circuit; the mover force sensor connecting plate 110 is connected with the force sensor 111 from top to bottom, the force sensor 111 is connected with the module connecting piece 104 from top to bottom, the module connecting piece 104 is connected with the gravity balance cylinder 102, and the compensation effect is directly applied to the module connecting piece 104, and the feedback value of the force sensor 111 is the resultant force of the module connecting piece 104, so that the feedback value of the force sensor 111 is directly the reading after gravity compensation.

[0086] The voice coil motor stator 106 is embedded with an annular magnet, the voice coil motor mover 108 is composed of a packaged annular coil, and the voice coil motor mover 108 generates electromagnetic force with the magnetic field generated by the voice coil motor stator 106 magnet after current is passed, and drives the mover to move.

[0087] As shown in Figure 4 The planetary polishing mechanism module is symmetrically designed from top to bottom, the module connecting piece 104 of the voice coil motor force control module with gravity balance can be connected with the planetary polishing mechanism module, so as to ensure that the force direction passes through the center of the planetary polishing mechanism module; the planetary polishing mechanism module mainly includes, from top to bottom, a force control-planet connecting plate 202, a planetary servo motor 203, a planetary servo motor support plate 204, a planetary mechanism 205, an eccentricity adjustment quick connection support plate 206, an eccentricity adjustment quick connector 207, and a small grinding head 201.

[0088] The force control-planet connecting plate 202 is connected with the planetary servo motor support plate 204, so as to facilitate quick connection with the module connecting piece 104 of the voice coil motor force control module with gravity balance; the planetary mechanism 205 is connected through the planetary servo motor support plate 204, so as to keep the inner gear ring in the planetary mechanism 205 fixed; the servo motor 203 directly drives the sun gear in the planetary mechanism 205 through the output shaft, and the inner gear ring in the mechanism is fixed, so as to drive the planetary gear in the planetary mechanism 205 to produce planetary motion; the small grinding head 201 is connected with the output shaft of the planetary gear in the planetary mechanism 205, so as to realize the planetary motion of the small grinding head 201 acting on the polishing of the optical element.

[0089] In order to obtain the eccentricity-adjustable planetary polishing mechanism, the universal eccentricity adjustment quick connector 207 is provided for the planetary polishing mechanism, the universal eccentricity adjustment quick connector 207 is connected with the planetary polishing mechanism through the eccentricity adjustment quick connection support plate 206, and is connected with the planetary gear output shaft of the planetary mechanism 205 through a bearing, so as to realize the transmission of the revolution motion of the planetary mechanism.

[0090] As shown in Figure 5As shown, the eccentricity adjustment module 208 is equipped to obtain different eccentricity requirements of the planetary polishing mechanism. The eccentricity adjustment module can be set according to the required eccentricity requirement, and the different eccentricity requirements can be realized by outputting different distances from the hole position to the center of the module; the eccentricity adjustment module 208 is connected with the universal eccentricity adjustment quick connector 207 equipped with the planetary polishing mechanism through threads, and the eccentricity of the planetary polishing mechanism can be quickly adjusted by replacing the eccentricity adjustment module 208 with different holes.

[0091] By connecting the planetary polishing mechanism module on the voice coil motor force control module with gravity balance, when the moving part of the voice coil motor force control module with gravity balance moves, it will drive the movement of the planetary polishing mechanism module and generate contact pressure when the optical element is in contact, and the gravity of the optical element will be compensated by the voice coil motor force control module with gravity balance.

[0092] As shown in Figure 6 , the low-frequency macro-vibration module mainly consists of a force control macro-vibration connecting piece 301, an optical rod slide rail 302, a linear bearing 303, a conformal grinding head 304, a macro-vibration linear slide rail 305, a macro-vibration linear slide block 306, a macro-vibration voice coil motor mover 307, and a macro-vibration voice coil motor stator 308; the low-frequency macro-vibration module is connected with the voice coil motor force control module with gravity balance through the module connecting piece 104 and the force control macro-vibration connecting piece 301; the optical rod slide rail 302 and the linear bearing 303 of the low-frequency macro-vibration module constitute a main sliding pair, the macro-vibration linear slide rail 305 and the macro-vibration linear slide block 306 constitute a secondary sliding pair, and the main and secondary sliding pair structure can further improve the structural rigidity and vibration reliability; the macro-vibration voice coil motor mover 307 moves under the electromagnetic interaction current input of the macro-vibration voice coil motor stator 308, the low-frequency macro-vibration module generates a low-frequency millimeter-level amplitude motion less than 50Hz along the main and secondary sliding pair, and acts on the optical element through the macro-vibration conformal grinding head 304.

[0093] As shown in Figure 7 , the high-frequency micro-vibration module mainly consists of a connecting main clamp 401, a connecting secondary clamp 402, a piezoelectric vibration unit 403, and a micro-vibration conformal grinding head 404, which realizes a micrometer-level motion greater than 50Hz. The high-frequency micro-vibration module is connected with the voice coil motor force control module with gravity balance through the module connecting piece 104, the connecting main clamp 401 and the connecting secondary clamp 402 of the high-frequency micro-vibration module constitute a double-point installation layout to strengthen the fixing strength of the piezoelectric vibration unit 403; the micro-vibration conformal grinding head 404 is connected with the piezoelectric vibration unit 403, and the axis position of the micro-vibration conformal grinding head 404 is consistent with the force control center position to ensure the stability of the contact pressure during processing.

[0094] Through the modular combination, the application can flexibly select the planetary polishing, low-frequency macro-vibration polishing or high-frequency micro-vibration polishing mode according to the machining requirements of different optical parts, and realize high-precision and stable force control through the voice coil motor with gravity balance, so as to guarantee the constancy of contact force and the consistency of machining quality in the polishing process, and effectively realize efficient and high-precision force control polishing machining of complex morphology optical parts. Figure 8 As shown in the optical element machining result, the RMS can reach about 10 nanometers.

[0095] As shown in the optical element machining result, the RMS can reach about 10 nanometers. Figure 9 As shown in the optical element machining result, the RMS can reach about 10 nanometers.

[0096] S101, a direct driving force is generated by using a voice coil module, and the force is flexible rather than rigid;

[0097] S102, a gravity compensation structure is constructed, and a pneumatic compensation force is generated by using a pneumatic cylinder to realize gravity compensation of the end module.

[0098] S103, a multi-module force control device structure is constructed to realize quick switching and compatible integration of multiple machining modes;

[0099] S104, high-precision force control is realized by feedback of a force sensor combined with a control system, and the force and displacement are monitored and controlled by using a sensor system;

[0100] S105, according to different process requirements, small grinding head planetary polishing or conformal vibration polishing is adopted to realize efficient and high-precision material removal, so as to obtain optical elements with high surface precision and quality;

[0101] S106, through structural design, the overall structure of the device is effectively integrated, so that the function, stability and high rigidity of the device are guaranteed, and the volume is effectively reduced.

[0102] I. The specific application field or related product of the application.

[0103] High-end optical element production and machining: suitable for industrial precision polishing of large-curvature complex surfaces such as large telescope main mirrors, astronomical optical elements and large-diameter laser system lenses, and meets the requirements of sub-micron geometric morphology and sub-nanometer roughness.

[0104] Manufacture of aspheric surface / free-form surface optical elements: for workpieces such as aspheric mirrors and free-form surface mirrors with continuously changing curvature, the high-frequency / low-frequency vibration module can realize field adaptive compensation, improve surface quality and machining efficiency, and solve the problem that traditional polishing methods are difficult to handle complex curved surface areas.

[0105] Precision optical component repair and reprocessing: suitable for on-site repair, defect repair, and surface reprocessing of high-value parts such as spacecraft helmet windows, military optical elements, and aviation photoelectric systems. By utilizing the flexible replacement capability of multiple modules, small grinding head repair can be realized, and vibration polishing can be switched to remove microscopic defects.

[0106] Suppression of high-frequency errors in optical elements: The invention combines high-frequency micro-vibration and low-frequency macro-vibration modules to effectively physically remove medium and high-frequency errors on the surface of optical elements. The device adopts modular design, the polishing head has a certain flexibility, and is integrated and coupled with the vibration unit to realize physical removal of local micro-scale defects or high-frequency ripples while maintaining stable contact on a large area, especially suitable for high-end optical applications sensitive to surface fluctuations, such as space telescope mirrors, laser focusing lenses, and advanced photoelectric windows.

[0107] Robot flexible automation integrated manufacturing system: The device is compatible with mainstream industrial robot end interfaces (6-axis, multi-joint, collaborative type), can be embedded into an automated production line, realizes flexible and soft control integrated processing, and is suitable as a standard end execution module to expand to the field of multi-category optical component production line automation.

[0108] The invention replaces traditional rigid polishing equipment with a robot end modular, covering multiple application fields such as large-diameter complex curved surface, ultra-high precision optical element development, high-value part repair, and advanced vibration polishing research, introducing an expandable, more efficient, and more accurate flexible force control polishing solution to the optical processing industry.

[0109] Second, the evidence related to the technical effects obtained by the embodiments of the invention.

[0110] The optical element robot end multi-module force control polishing device provided by the invention has the comprehensive advantages of high-precision force control, modular rapid switching, adaptive multi-curvature conformal processing, high-efficiency polishing, and high-quality surface generation. The device can flexibly adjust the processing mode according to the different shapes, sizes, and material properties of optical elements, thereby realizing compliant contact, stable force control, uniform material removal, and excellent surface quality control, significantly improving the intelligent level and process adaptability of the automated optical polishing system.

[0111] The designed implementation prototype is as shown in Figure 10 It can be carried on the end of a six-degree-of-freedom industrial robot to form a complete robot flexible polishing system. The integrated planetary wheel small grinding head polishing system in the figure is suitable for efficient and uniform material removal of optical components with large curvature or complex aspherical surface topography. The system has completed preliminary experimental verification, and the results show that in the processing of aspherical mirrors, the surface PV value control is better than 70nm, and the surface quality is significantly improved.

[0112] In addition, as shown in Figure 11 In addition, as shown in

[0113] The present application improves the overall performance of the optical element automatic polishing system by multi-module cooperation, multi-strategy fusion and high adaptability structure design, and provides a feasible technical solution for intelligent machining of complex curved surface optical parts on the basis of ensuring high-precision force control, which has good engineering popularization prospect and industrial application value.

[0114] The above is only a specific embodiment of the present application, but the protection scope of the present application is not limited thereto, any modification, equivalent replacement and improvement within the technical range disclosed by the present application and within the spirit and principles of the present application should be covered within the protection scope of the present application.

Claims

1. A multi-module force-controlled polishing device for the end effector of an optical element robot, characterized in that, include: A gravity-balanced voice coil motor force control module, a planetary polishing mechanism module, a low-frequency macro vibration module, and a high-frequency micro vibration module; The gravity-balanced voice coil motor force control module consists of its mover and stator, including a gravity balance module support, a gravity balance cylinder, a gravity balance guide rail, a module connector, an overall frame connector, a voice coil motor stator, an overall frame side support plate, a voice coil motor mover, a mover slider connector, a mover force sensor connector, a force sensor, a linear guide rail, a linear slider, and a packaged support plate; The mover of the gravity-balanced voice coil motor force control module includes: a gravity-balanced cylinder, a module connector, a voice coil motor mover, a mover slider connector, a mover force sensor connector plate, a force sensor, and a linear slider; The voice coil motor force control module stator with gravity balance includes: gravity balance module support, gravity balance guide rail, integral frame connector, voice coil motor stator, integral frame side support plate, linear slide rail, and encapsulation support plate. The gravity-balanced voice coil motor force control module can be modularly connected with the planetary polishing mechanism module, the low-frequency macro vibration module, and the high-frequency micro vibration module to achieve rapid debugging and switching of various processes.

2. The multi-module force-controlled polishing device for the end effector of an optical element robot as described in claim 1, characterized in that, The gravity balance cylinder has two cylinders symmetrically distributed on the left and right sides, and the gravity balance guide rail has four cylinders symmetrically distributed on the left and right sides. The linear slide rails are two in number and symmetrically distributed on the left and right sides, and the linear sliders are two in number and symmetrically distributed on the left and right sides.

3. The multi-module force-controlled polishing device for the end effector of an optical element robot as described in claim 1, characterized in that, The gravity balance cylinder and gravity balance guide rail are located on the outside of the overall frame connector, while the linear slide rail and linear slider are located on the inside of the overall frame connector.

4. The multi-module force-controlled polishing device for the end effector of an optical element robot as described in claim 1, characterized in that, The module connector, the overall frame connector, and the mover slider connector are all U-shaped. The module connector is connected to the mover slider connector via the mover force sensor connecting plate and the force sensor. The overall frame connector is embedded in the module connector and can slide along four gravity balance guide rails. The mover slider connector is embedded in the overall frame connector and can slide along two linear slide rails. The rigidity of the force control module is improved by the cross-embedded sliding method. The mover can generate single-degree-of-freedom motion along four gravity balance guide rails and two linear slide rails. Since the gravity balance guide rails and the two linear slide rails are all located on the left and right sides, it has high vibration resistance in this direction of motion.

5. The multi-module force-controlled polishing device for the end effector of an optical element robot as described in claim 1, characterized in that, The gravity balancing cylinder can adjust the pressure of the support through a pneumatic circuit to match the gravity, thus achieving adjustable constant gravity compensation; and can further achieve active adjustable gravity compensation through an active pneumatic control circuit.

6. The multi-module force-controlled polishing device for the end effector of an optical element robot as described in claim 1, characterized in that, The force sensor connecting plate connects to the force sensor from top to bottom, and the force sensor connects to the module connector from top to bottom. The module connector is connected to the gravity balance cylinder, so that the compensation effect is directly applied to the module connector. The feedback value of the force sensor is the resultant force of the module connector, so that the feedback value of the force sensor is directly the reading after gravity compensation.

7. The multi-module force-controlled polishing device for the end effector of an optical element robot as described in claim 1, characterized in that, The stator of the voice coil motor is embedded with a ring magnet, and the mover of the voice coil motor is composed of an encapsulated ring coil. When current is passed through the mover of the voice coil motor, it generates an electromagnetic force with the magnetic field generated by the magnet of the voice coil motor stator, which drives the mover to move. The planetary polishing mechanism module is symmetrically designed from top to bottom. It can be connected to the planetary polishing mechanism module through a module connector with a gravity-balanced voice coil motor force control module to ensure that the direction of the force passes through the center of the planetary polishing mechanism module. The planetary polishing mechanism module mainly includes, from top to bottom, a force control-planetary connection plate, a planetary servo motor, a planetary servo motor support plate, a planetary mechanism, an eccentricity adjustment quick-connect support plate, an eccentricity adjustment quick-connect piece, and a small grinding head. The force control-planetary connection plate connects to the planetary servo motor support plate, facilitating quick connection of the planetary polishing mechanism with the gravity-balanced voice coil motor force control module.

8. The multi-module force-controlled polishing device for the end effector of an optical element robot as described in claim 1, characterized in that, The planetary mechanism is connected via a planetary servo motor support plate, thereby keeping the internal gear ring in the planetary mechanism fixed.

9. The multi-module force-controlled polishing device for the end effector of an optical element robot as described in claim 1, characterized in that, The servo motor directly drives the sun gear in the planetary mechanism through the output shaft, while the internal gear ring in the mechanism is fixed, thereby driving the planet gears in the planetary mechanism to generate planetary motion; The small grinding head is connected to the output shaft of the planetary gear in the planetary mechanism to realize the planetary motion of the small grinding head that acts on the polishing of the optical element; In order to obtain a planetary polishing mechanism with adjustable eccentricity, a universal eccentricity adjustment quick connector is provided for the planetary polishing mechanism. The universal eccentricity adjustment quick connector is connected to the planetary polishing mechanism through the eccentricity adjustment quick connector support plate, and is connected to the output shaft of the double planetary gear of the planetary mechanism through a bearing, thereby realizing the transmission of the planetary mechanism's revolution motion. Equipped with an eccentricity adjustment module to obtain the planetary polishing mechanism's requirements for different eccentricities; the eccentricity adjustment module can set different openings according to the required different eccentricity requirements, and different eccentricities can be set by varying the distance between the output hole and the center of the module. The eccentricity adjustment module is connected to the universal eccentricity adjustment quick connector equipped with the planetary polishing mechanism by threads, and the eccentricity of the planetary polishing mechanism can be quickly adjusted by replacing the eccentricity adjustment module with different openings. The input and output shafts of the eccentricity adjustment module are connected by a multi-stage gear transmission, and the input shaft is the output shaft of the planetary mechanism, thereby realizing the transmission of motion information of the planetary mechanism; By connecting the planetary polishing mechanism module to the gravity-balanced voice coil motor force control module, when the mover of the gravity-balanced voice coil motor force control module moves, it will drive the planetary polishing mechanism module to move and generate contact pressure when it comes into contact with the optical element. Its own gravity is compensated by the gravity-balanced voice coil motor force control module. The low-frequency macro vibration module mainly consists of force-controlled macro vibration connectors, smooth rod slide rails, linear bearings, conformal grinding heads, macro vibration linear slide rails, macro vibration linear sliders, macro vibration voice coil motor movers, and macro vibration voice coil motor stators. The connection between the gravity-balanced voice coil motor force control module and the low-frequency macro vibration module is achieved through the module connector and the force-controlled macro vibration connector. The optical rod slide rail and linear bearing of the low-frequency macro vibration module form the main sliding pair, while the macro vibration linear slide rail and macro vibration linear slider form the secondary sliding pair. The main and secondary double sliding pair structure can further improve the structural rigidity and vibration reliability. The macro-vibration motor mover moves under the electromagnetic interaction current input of the macro-vibration motor stator. The low-frequency macro-vibration module generates a low-frequency millimeter-level amplitude motion of less than 50Hz along the main and auxiliary double sliding pairs, and acts on the optical element through the macro-vibration conformal grinding head. The high-frequency micro-vibration module mainly consists of a main connecting fixture, a secondary connecting fixture, a piezoelectric vibration unit, and a micro-vibration conformal grinding head, achieving micron-level motion at >50Hz; The high-frequency micro-vibration module is connected via a modular connector. The main and auxiliary clamps of the high-frequency micro-vibration module form a dual-point installation layout to enhance the fixing strength of the piezoelectric vibration unit. The micro-vibration conformal grinding head is connected to the piezoelectric vibration unit. The axis of the micro-vibration conformal grinding head is aligned with the force control center to ensure stable contact pressure during processing. The modular connectors are compatible with other modules, enabling process replacement of multiple modules.

10. A method for implementing the multi-module force-controlled polishing device for the end effector of an optical element robot as described in any one of claims 1-9, characterized in that, The method for the multi-module force-controlled polishing device at the end of a robot for optical components includes: Step 1: Use the voice coil module to generate direct drive force, which is compliant rather than rigid. Step 2: Construct a gravity compensation structure and use a cylinder to generate pneumatic compensation force to achieve gravity compensation for the end module. Step 3: Construct a multi-module force control device structure to achieve rapid switching and compatible integration of multiple processing modes; Step 4: Achieve high-precision force control by combining force sensor feedback with the control system, using the sensor system to monitor and control force and displacement; Step 5: Depending on the different process requirements, planetary polishing with small grinding heads or conformal vibration polishing are used to achieve efficient and high-precision material removal in order to obtain optical components with high surface accuracy and quality. Step Six: Through structural design, effectively integrate the overall structure of the device to ensure its functionality, stability, and high rigidity while effectively reducing its volume.

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