An ultra-precision active-passive integrated piezoelectric vibration isolation platform for optical collimation

Abstract

The application discloses an ultra-precision active and passive integrated piezoelectric vibration isolation platform for optical collimation, which comprises a base, a vertical vibration isolation device, a horizontal vibration isolation device, piezoelectric ceramic actuators, a laser displacement sensor, an acceleration sensor, a limiting device, an upper bearing platform, a two-dimensional acoustic black hole damping enhancement structure, optical devices, a control unit and a driving unit; the base is a back-shaped plate, the upper bearing platform is a three-layer composite structure, the vertical and horizontal vibration isolation devices realize passive vibration isolation, the eight piezoelectric ceramic actuators cooperate with the sensor and the control unit to realize active vibration isolation, the two-dimensional acoustic black hole damping enhancement structure absorbs residual medium and high frequency vibrations, and the limiting device realizes safety protection. The application adopts integrated design, has compact structure and high precision, can simultaneously suppress multi-directional vibrations, has a load adaptive mechanism, has excellent active and passive composite vibration isolation effect, has a modular structure and is convenient to disassemble and assemble, and is widely applied in the fields of precise optical instruments, semiconductors and the like.

Description

Technical Field

[0001] This invention relates to the field of precision vibration isolation technology, specifically to an ultra-precision integrated active and passive piezoelectric vibration isolation platform for optical collimation, which is suitable for fields with extremely high requirements for vibration control, such as precision optical instruments and semiconductors. Background Technology

[0002] The integrated active-passive piezoelectric vibration isolation platform is based on the principle of combined active-passive vibration isolation. Its core function is to suppress vibrations in the vertical and horizontal directions during the operation of precision optical instruments, preventing vibrations from affecting the instrument's performance. It cancels vibration interference through the synergistic effect of vertical and horizontal vibration isolation mechanisms. For mid-to-high frequency vibrations, conventional solutions would design a vertical unloading mechanism in the vertical direction and arrange vibration damping devices in the horizontal direction; for mid-to-low frequency interference, active vibration isolation would be achieved through piezoelectric ceramic actuators, sensors, and control algorithms.

[0003] However, existing vibration reduction platforms have many technical limitations in practical applications: First, the vibration isolation coordination is seriously insufficient. The vertical and horizontal vibration isolation mechanisms are independent of each other, lacking an integrated structural design and supporting control algorithms, making it difficult to effectively cope with multi-directional composite vibrations. Second, there is no load adaptive mechanism. Load changes can easily lead to a decline in vibration isolation performance, making it impossible to maintain a stable vibration isolation effect under different load conditions. Third, the absorption effect of mid-to-high frequency residual vibrations is poor. Some vibration reduction platforms lack dedicated damping reinforcement structures, and mid-to-high frequency vibrations remain after active and passive vibration isolation, affecting the accuracy of precision instruments. Fourth, the space utilization rate of the vibration isolation structure is low. The load-bearing capacity and stiffness design flexibility of conventional elastic elements are insufficient, making it difficult to adapt to the comprehensive requirements of precision equipment in terms of space, weight, and performance. Summary of the Invention

[0004] This invention addresses the shortcomings of existing technologies by providing an ultra-precision integrated active and passive piezoelectric vibration isolation platform for optical collimation. It solves technical problems such as insufficient vibration isolation coordination, difficulty in coping with complex vibrations, performance degradation due to load changes, and poor absorption of mid-to-high frequency residual vibrations in existing platforms. It achieves precise and coordinated vibration isolation of multi-directional vibrations, improves vibration isolation accuracy and stability, and is adaptable to different loads and vibration frequency conditions.

[0005] To achieve the above-mentioned objectives, the present invention adopts the following technical solution: An ultra-precision integrated active and passive piezoelectric vibration isolation platform for optical collimation includes a base, a vertical vibration isolation device, a horizontal vibration isolation device, a piezoelectric ceramic actuator, a laser displacement sensor, an acceleration sensor, a limiting device, an upper bearing platform, a two-dimensional acoustic black hole damping enhancement structure, optical components, a control unit, and a drive unit.

[0006] The base has a U-shaped plate structure, which facilitates heat dissipation and effectively avoids local heat accumulation. The upper support platform is used to fix various components and reserves the installation position of the PCB motherboard. It consists of a surface layer, a rubber layer and a mounting layer. The surface layer has high wear resistance and corrosion resistance after hard anodizing treatment. The rubber layer can effectively absorb and isolate vibration. The mounting layer is used to securely connect with components such as the two-dimensional acoustic black hole damping enhancement structure and piezoelectric ceramic actuator.

[0007] The vertical vibration isolation device consists of an X-shaped lifting platform, diaphragm springs, electric push rods, sleeves, springs, sliders, micro motors, pulley blocks, and several connecting rods. The micro electric push rods drive the X-shaped lifting platform to achieve active leveling, while the self-locking characteristic of the electric push rods ensures the stability of the adjusted position. The micro motors change the position of the sliders, adjusting the stiffness of the diaphragm springs to achieve passive vibration isolation at different frequencies. The horizontal vibration isolation device consists of multiple superstructure passive vibration damping devices, specifically eight superstructure passive vibration damping units, four symmetrically arranged in each of the X and Y directions. Each superstructure vibration damping unit consists of 24 sets of local resonant structures, and each local resonant structure consists of two compliant elastic beams and a lead block oscillator, providing wideband gap vibration isolation in the horizontal direction. The vertical and horizontal vibration isolation devices work together to achieve passive vibration isolation.

[0008] There are eight piezoelectric ceramic actuators in total, four in the vertical direction and four in the horizontal direction. The lower end of the vertical piezoelectric ceramic actuator has a certain gap with the base, and the upper end is connected to the lower surface of the upper support platform. The horizontal piezoelectric ceramic actuator is installed on the lower surface of the upper support platform. Under the action of the driver, the piezoelectric ceramic actuator achieves active vibration isolation in three directions, which greatly improves the active vibration isolation performance under combined vibration.

[0009] Four laser displacement sensors and eight accelerometers are used. The signals output from the sensors are first amplified by operational amplifiers in the conditioning circuit, and then the amplified signals are connected to the control unit through a multiplexer, realizing efficient centralized acquisition of multiple signals. The sensors support standard communication protocols and can adapt to different data transmission requirements. The laser displacement sensors monitor vibration interference in real time, and the signals collected by the accelerometers are input to the control unit for composite active control, predicting the impact of vibration on the upper bearing platform and driving the piezoelectric ceramic actuator to work, achieving the effect of active vibration reduction.

[0010] The control unit is based on the PIC16F877A microcontroller and integrates a dual closed-loop controller and a mode decoupling module. It can receive signals from the laser displacement sensor and the acceleration sensor and drive the piezoelectric ceramic actuator. By changing the control algorithm parameters, the impact of low- and medium-frequency interference on the precision optical platform device can be effectively reduced.

[0011] The limiting device consists of four sets of cylinders, which are bolted to the lower surface of the upper support platform and the base, with a certain gap between them. This gap ensures that the active and passive vibration isolation performance is not affected during normal operation of the equipment. When the platform encounters abnormal working conditions such as overload or external impact, the limiting device can strictly limit the vertical and horizontal displacement of the platform within a safe range through mechanical contact, thereby protecting the ultra-structural passive vibration damping device, piezoelectric ceramic actuator, optical components and other precision instruments from mechanical damage, and providing the final safety protection for the entire optical vibration isolation platform.

[0012] The two-dimensional acoustic black hole damping reinforcement structure consists of two-dimensional acoustic black hole damping and damping material layers. It is installed on the lower surface of the upper bearing platform by bolt connection. It is used to absorb the medium and high frequency vibrations that remain in the upper bearing platform after passing through the active and passive vibration isolation system. It has the advantages of simple structure and obvious vibration reduction effect.

[0013] Optical components are mounted on the upper support platform via brackets. The platform is made of aluminum alloy and has a modular structure, which is easy to disassemble and allows for the replacement of parts to meet different needs.

[0014] Furthermore, the platform features a load adaptive mechanism. Through the extension and retraction of an electric actuator in conjunction with potentiometer feedback, it senses the load mass in real time and adjusts the system stiffness accordingly, ensuring the natural frequency of the passive vibration isolation system remains stable under varying loads. The potentiometer signal, after being switched by a multiplexer, is acquired by the ADC port of the control unit, ultimately achieving adaptive adjustment of the natural frequency through a closed-loop process. This fundamentally solves the performance degradation problem caused by load changes in traditional vibration isolation devices. Simultaneously, by altering the structural parameters of the superstructure unit and the stiffness of the diaphragm spring at the top of the X-shaped lifting platform, excellent passive vibration reduction effects can be achieved against different mid-to-high frequency interferences.

[0015] Compared with the prior art, the present invention has the following beneficial effects: 1. This invention adopts an integrated design, which is compact and highly precise, and can suppress vibrations in multiple directions at the same time, thereby further improving the vibration isolation performance.

[0016] 2. The device of this invention adopts a U-shaped design, which facilitates heat dissipation and effectively avoids local heat accumulation. At the same time, its modular structure is easy to disassemble, and the components can be replaced to adapt to different needs.

[0017] 3. To address the issue of insufficient vibration isolation synergy in existing vibration reduction platforms, the active vibration isolation performance under combined vibration is further improved by using eight piezoelectric ceramic actuators arranged in the horizontal and vertical directions (four in the vertical direction and four in the horizontal direction).

[0018] 4. The vertical vibration isolation device of this invention uses a miniature electric actuator to drive an X-shaped lifting platform. The upper surface of the lifting platform, the diaphragm spring, and the sleeve are connected sequentially by bolts and nuts, enabling active leveling for different external loads. Simultaneously, the self-locking characteristic of the electric actuator ensures the stability of the adjusted position.

[0019] 5. The horizontal vibration isolation device of this invention consists of eight symmetrically arranged superstructure passive vibration reduction units (four in each of the X and Y directions). Each superstructure vibration reduction unit consists of 24 sets of local resonant structures, and each local resonant structure consists of two compliant elastic beams and a lead block oscillator. This superstructure device can provide large-amplitude broadband gap vibration isolation in the horizontal direction.

[0020] 6. This invention utilizes a variable stiffness diaphragm spring device in the vertical unloading mechanism. Compared to common cylindrical helical springs, diaphragm springs offer greater load-bearing capacity and designable stiffness characteristics within the same space, making them more advantageous in precision equipment with comprehensive requirements for space, weight, and performance. By adjusting the radial position of the slider using a micro-motor, the stiffness of the diaphragm spring is changed, achieving passive vibration isolation effects at different frequencies.

[0021] 7. The two-dimensional acoustic black hole damping enhancement structure of this invention is fixed to the lower surface of the upper bearing platform by bolt connection. It can effectively absorb the mid-to-high frequency vibrations that remain in the upper bearing platform after passing through the active and passive vibration isolation system. It has the advantages of simple structure and significant vibration reduction effect.

[0022] 8. The limiting device of this invention consists of four sets of cylinders. The cylinders are bolted to the lower surface of the upper support platform and the base, with a certain gap reserved between them. This gap ensures that the active and passive vibration isolation performance is not affected during normal operation of the equipment. When the platform encounters abnormal working conditions such as overload or external impact, the limiting device can strictly limit the vertical and horizontal displacement of the platform within a safe range through mechanical contact, thereby protecting the ultra-structural passive vibration damping device, piezoelectric ceramic actuator, optical components and other precision instruments from mechanical damage, providing ultimate safety protection for the entire optical vibration isolation platform.

[0023] 9. The upper support platform of this invention consists of a surface layer, a rubber layer, and a mounting layer. The surface layer is aesthetically pleasing, the rubber layer provides vibration damping, and the mounting layer secures it to other components. The surface layer, after hard anodizing, exhibits high wear resistance and corrosion resistance; the middle rubber layer effectively absorbs and isolates vibrations; and the bottom mounting layer is used for secure connection with components such as the two-dimensional acoustic black hole damping enhancement structure and piezoelectric ceramic actuators.

[0024] 10. The laser displacement sensor of the present invention can monitor vibration interference in real time. By inputting the monitored signal into the control unit, the impact of vibration on the upper bearing platform can be predicted. At the same time, combined with the signal collected by the acceleration sensor, composite active control is performed to drive the piezoelectric ceramic actuator to achieve the effect of active vibration reduction, thereby ensuring the stable operation of the optical platform device.

[0025] 11. This invention achieves excellent active vibration isolation through eight sets of piezoelectric ceramic actuators, four laser displacement sensors, eight accelerometers, and a control unit. It effectively reduces the impact of low-frequency interference on precision optical platform devices.

[0026] 12. This invention fundamentally solves the performance degradation problem of traditional vibration isolation devices caused by load changes through a load adaptive mechanism. The system uses an electric actuator extension and retraction combined with potentiometer feedback to sense the load mass in real time and adjust the system stiffness, ensuring that the natural frequency of the passive vibration isolation system remains stable under different loads. The device is made of aluminum alloy and utilizes the self-locking function of the electric actuator to ensure stability after adjustment. The potentiometer signal is switched by a multiplexer and then acquired by the ADC port of the control unit, ultimately achieving adaptive adjustment of the natural frequency through the aforementioned closed loop.

[0027] 13. The signal output from the sensor of this invention is first amplified by an operational amplifier in the conditioning circuit, and then the amplified signal is connected to the control unit through a multiplexer, realizing efficient centralized acquisition of multiple signals. The sensor supports standard communication protocols and can adapt to different data transmission requirements.

[0028] 14. This invention employs a combined active and passive vibration isolation technology, achieving precise and coordinated integrated vibration isolation. By changing the control algorithm parameters, the impact of low- and mid-frequency interference on precision optical platform devices can be effectively reduced. By altering the structural parameters of the superstructure unit and the stiffness of the diaphragm spring at the upper end of the X-shaped lifting platform, excellent passive vibration reduction effects can be achieved against different low- and mid-frequency interferences. Attached Figure Description

[0029] Figure 1 This is an external schematic diagram of the ultra-precision integrated active and passive piezoelectric vibration isolation platform for optical collimation of the present invention; Figure 2 This is an internal schematic diagram of the ultra-precision active-passive integrated piezoelectric vibration isolation platform for optical collimation of the present invention; Figure 3 This is a schematic diagram of the vertical vibration isolation device of the present invention; Figure 4 This is a schematic diagram of the structure of the superstructure passive vibration reduction unit of the present invention; Figure 5 This is a schematic diagram of the two-dimensional acoustic black hole damping enhancement structure of the present invention.

[0030] In the diagram: 1. Optical component, 2. Rubber layer, 3. Upper support platform mounting layer, 4. Upper support platform surface layer, 5. Optical component, 6. Base, 7. Two-dimensional acoustic black hole damping enhancement structure, 8. Limiting device, 9. Laser displacement sensor, 10. Vertical piezoelectric ceramic actuator, 11. Superstructure passive vibration reduction unit, 12. Horizontal piezoelectric ceramic actuator, 13. Accelerometer, 14. Vertical vibration isolation device, 301. Sleeve, 302. Diaphragm spring, 303. Spring, 304. Slider, 305. Micro motor, 306. Pulley block, 307. Micro electric push rod, 401. Compliant elastic beam, 402. Lead block oscillator, 501. Two-dimensional acoustic black hole damping, 502. Damping material layer. Detailed Implementation

[0031] To make the technical solution, objective, and beneficial effects of the present invention clearer, the present invention will be further described in detail below with reference to the accompanying drawings and preferred embodiments. It should be understood that the preferred embodiments described herein are for illustrative purposes only and are not intended to limit the scope of the invention.

[0032] like Figures 1-5 As shown, an ultra-precision integrated active and passive piezoelectric vibration isolation platform for optical collimation includes optical devices 1 and 5, a rubber layer 2, an upper bearing platform mounting layer 3, an upper bearing platform surface layer 4, a base 6, a two-dimensional acoustic black hole damping enhancement structure 7, a limiting device 8, a laser displacement sensor 9, a vertical piezoelectric ceramic actuator 10, an ultra-structure passive vibration reduction unit 11, a horizontal piezoelectric ceramic actuator 12, an acceleration sensor 13, and a vertical vibration isolation device 14. The vertical vibration isolation device 14 further includes a sleeve 301, a diaphragm spring 302, a spring 303, a slider 304, a micro motor 305, a pulley block 306, and a micro electric push rod 307. The ultra-structure passive vibration reduction unit 11 includes a compliant elastic beam 401 and a lead block oscillator 402. The two-dimensional acoustic black hole damping enhancement structure 7 includes a two-dimensional acoustic black hole damper 501 and a damping material layer 502.

[0033] The assembly process of the ultra-precision integrated active and passive piezoelectric vibration isolation platform for optical collimation of the present invention is as follows: The vertical vibration isolation device 14 is installed in the matching slots of the upper bearing platform mounting layer 3 and the base 6 by bolts and nuts, thus completing the fixation of the vertical passive vibration isolation structure. The limiting device 8, laser displacement sensor 9, superstructure passive vibration reduction unit 11 and horizontal piezoelectric ceramic actuator 12 are fixed on the base 6 respectively, and the acceleration sensor 13 is fixed on one end of the horizontal piezoelectric ceramic actuator 12, thus completing the fixing of the horizontal passive vibration isolation structure, active vibration isolation actuator structure and sensing structure. Optical devices 1 and 5 are mounted on the surface layer 4 of the upper support platform using brackets. The two-dimensional acoustic black hole damping enhancement structure 7 is fixed to the lower surface of the upper support platform mounting layer 3 by bolts, thus completing the fixing of the optical devices and the damping enhancement structure. Finally, the upper support platform is secured to the base with bolts and nuts to complete the assembly of the entire machine.

[0034] The ultra-precision integrated active and passive piezoelectric vibration isolation platform for optical collimation of the present invention has the following working process: After the power is turned on, the system enters the working state: Signal acquisition: The laser displacement sensor 9 and the acceleration sensor 13 installed at one end of the piezoelectric ceramic actuator monitor the vibration interference in the vertical and horizontal directions in real time. The electrical signal output by the sensor is first amplified by the operational amplifier in the conditioning circuit, and the amplified signal is then connected to the control unit with PIC16F877A microcontroller as the core through the multiplexer. Active vibration isolation control: The dual closed-loop controller and modal decoupling module integrated in the control unit process the collected signals, and combine them with the signals from the laser displacement sensor and acceleration sensor to perform composite active control, driving the horizontal piezoelectric ceramic actuator 12 to generate a canceling force that is equal in magnitude and opposite in direction to the horizontal vibration interference, thereby achieving active vibration reduction in the horizontal direction; at the same time, it drives the micro electric push rod 307 to work, cooperating with the action of the vertical piezoelectric ceramic actuator 10 to achieve active vibration reduction in the vertical direction; Passive vibration isolation coordination: The diaphragm spring 302 in the vertical vibration isolation device 14 is driven by the micro motor 305 to adjust the stiffness of the slider 304 according to the actual vibration frequency, so as to achieve passive vibration isolation in the vertical direction; the super-structure passive vibration reduction unit 11 of the horizontal vibration isolation device drives the lead block oscillator 402 to vibrate synchronously through the compliant elastic beam 401, so as to achieve wideband passive vibration isolation in the horizontal direction. Residual vibration absorption: The mid-to-high frequency residual vibrations after passing through the active and passive vibration isolation system are absorbed by the two-dimensional acoustic black hole damping enhancement structure 7 on the lower surface of the upper bearing platform, further reducing the vibration of the upper bearing platform; Load adaptive adjustment: The electric push rod 307 telescopically coordinates with potentiometer feedback to sense the load mass of the upper bearing platform in real time. The potentiometer signal is switched by a multiplexer and then collected by the ADC port of the control unit. The control unit adjusts the system stiffness according to the load change to keep the natural frequency of the passive vibration isolation system stable. Safety protection: When the equipment is running normally, the gap between the limit device 8 and the base and the upper bearing platform ensures that the vibration isolation performance is not affected; when the platform encounters abnormal working conditions such as overload or external impact, the limit device 8 strictly limits the vertical and horizontal displacement of the upper bearing platform within a safe range through mechanical contact, protecting the core precision components from damage.

[0035] Through the synergistic effect of the above-mentioned active and passive combined vibration isolation, the vibration amplitude of the upper bearing platform is reduced, ensuring the stable operation of optical instruments installed on the platform and realizing ultra-precision optical collimation.

[0036] like Figures 1-5 The diagram shown is a schematic of an ultra-precision integrated active and passive piezoelectric vibration isolation platform for optical collimation provided by the present invention. It includes an optical device 1, a rubber layer 2, an upper bearing platform mounting layer 3, an upper bearing platform surface layer 4, an optical device 5, a base 6, a two-dimensional acoustic black hole damping enhancement structure 7, a limiting device 8, a laser displacement sensor 9, a vertical piezoelectric ceramic actuator 10, an ultra-structural passive vibration reduction unit 11, a horizontal piezoelectric ceramic actuator 12, an acceleration sensor 13, a vertical vibration isolation device 14, a sleeve 301, a diaphragm spring 302, a spring 303, a slider 304, a micro motor 305, a pulley block 306, a micro electric push rod 307, a compliant elastic beam 401, a lead block oscillator 402, a two-dimensional acoustic black hole damper 501, and a damping material layer 502. The assembly process is as follows: First, the vertical vibration isolation device 14 is installed in the matching slots of the upper bearing platform mounting layer 3 and the base 6 using bolts and nuts. Then, the limiting device 8, laser displacement sensor 9, superstructure passive vibration reduction unit 11, and horizontal piezoelectric ceramic actuator 12 are fixed to the base 6, and the acceleration sensor 13 is fixed to one end of the horizontal piezoelectric ceramic actuator 12. Optical components 1 and 5 are mounted on the surface layer 4 of the upper bearing platform using brackets, and the two-dimensional acoustic black hole damping enhancement structure 7 is fixed to the lower surface of the upper bearing platform mounting layer 3 using bolts. Finally, the upper bearing platform and the base are fixed tightly with bolts and nuts, thus completing the assembly of the entire machine.

[0037] After power is connected, the system operates as follows: the laser displacement sensor 9 and the accelerometer 13 installed at one end of the piezoelectric ceramic actuator monitor vibration interference in real time. The sensor output signal is amplified by the operational amplifier in the conditioning circuit, and then connected to the control unit through a multiplexer for composite active control. This drives the piezoelectric ceramic actuator 12 to generate a canceling force of equal magnitude and opposite direction, thereby achieving active vibration reduction in the horizontal direction. Simultaneously, it drives the electric push rod 307 to work, achieving active vibration reduction in the vertical direction. By reducing the vibration of the upper bearing platform, the stable operation of the optical instrument is ensured, achieving ultra-precision performance. During operation, the limiting device 8 can strictly limit the vertical and horizontal displacement of the platform within a safe range through mechanical contact, protecting the core components from damage and providing final safety protection for the entire optical vibration isolation platform.

[0038] like Figure 3As shown, the vertical vibration isolation device 14 mainly consists of a sleeve 301, a diaphragm spring 302, a spring 303, a slider 304, a micro motor 305, a pulley block 306, a micro electric push rod 307, and several connecting rods. The sleeve 301 is fixed to the diaphragm spring 302 with bolts and nuts; the diaphragm spring 302 is installed in the adapter slot of the upper platform of the X-shaped lifting mechanism with bolts and nuts; one end of the electric push rod 307 is fastened to the lower platform of the X-shaped lifting mechanism with bolts and nuts, and the other end is connected to the connecting rods with bolts and nuts. The operation of the micro motor 305 causes the slider 304 to change position, thereby adjusting the stiffness of the diaphragm spring to adapt to different working environments.

[0039] like Figure 4 As shown, the superstructure vibration damping unit consists of 24 sets of local resonant structures. Each local resonant structure comprises two compliant elastic beams 401 and a lead block oscillator 402. This superstructure device can provide large-amplitude broadband vibration isolation in the horizontal direction. The local resonant structures are arranged in an array. When horizontal vibration is introduced, the compliant elastic beams drive the lead block oscillator to vibrate synchronously, thereby achieving efficient vibration isolation. This superstructure vibration damping unit can not only cope with large-amplitude horizontal vibration impacts but also block vibration transmission over a wide frequency range.

[0040] like Figure 5 As shown, the two-dimensional acoustic black hole damping enhancement structure 7 consists of a two-dimensional acoustic black hole damper 501 and a damping material layer 502, and is fixed to the lower surface of the upper bearing platform by bolts. It can effectively absorb the mid-to-high frequency vibrations remaining in the upper bearing platform after passing through the active and passive vibration isolation system. It has the advantages of simple structure and significant vibration reduction effect.

[0041] The above embodiments of the present invention are merely illustrative of the technical concept and features of the present invention, and are intended to enable those skilled in the art to understand the content of the present invention and implement it accordingly. They should not be construed as limiting the scope of protection of the present invention. All equivalent changes or modifications made in accordance with the spirit and essence of the present invention should be covered within the scope of protection of the present invention.

Claims

1. An ultra-precision integrated active and passive piezoelectric vibration isolation platform for optical collimation, characterized in that, It includes a base (6), a vertical vibration isolation device (14), a horizontal vibration isolation device, a piezoelectric ceramic actuator, a laser displacement sensor (9), an acceleration sensor (13), a limiting device (8), an upper support platform, a two-dimensional acoustic black hole damping enhancement structure (7), optical components, a control unit, and a drive unit; the base (6) is a U-shaped plate structure, the upper support platform is used to fix each component and reserve a PCB motherboard mounting position, and the optical components are mounted on the table surface of the upper support platform through a bracket; The vertical vibration isolation device (14) works in conjunction with the horizontal vibration isolation device to achieve passive vibration isolation. The piezoelectric ceramic actuator achieves active vibration isolation in three directions under the action of the drive unit. The limiting device (8) restricts the large displacement of the platform in any direction. The two-dimensional acoustic black hole damping enhancement structure (7) is installed on the lower surface of the upper bearing platform by bolt connection to absorb the vibration of the upper bearing platform in any direction. The control unit is based on the PIC16F877A microcontroller, integrating a dual closed-loop controller and a mode decoupling module. It receives signals from the laser displacement sensor (9) and the acceleration sensor (13) and drives the piezoelectric ceramic actuator to work.

2. The ultra-precision integrated active and passive piezoelectric vibration isolation platform for optical collimation according to claim 1, characterized in that, The upper support platform consists of a surface layer (4), a rubber layer (2), and a mounting layer (3); the surface layer (4) is hard anodized, the rubber layer (2) is used to absorb and isolate vibration, and the mounting layer (3) is firmly connected to the two-dimensional acoustic black hole damping enhancement structure (7) and the piezoelectric ceramic actuator.

3. The ultra-precision integrated active and passive piezoelectric vibration isolation platform for optical collimation according to claim 1, characterized in that, The vertical vibration isolation device (14) consists of an X-shaped lifting platform, a diaphragm spring (302), an electric push rod (307), a sleeve (301), a spring (303), a slider (304), a micro motor (305), a pulley block (306), and several connecting rods. The sleeve (301) is bolted and nut-fixed to the diaphragm spring (302). The diaphragm spring (302) is installed in the adapter slot of the upper platform of the X-shaped lifting mechanism. One end of the electric push rod (307) is fastened to the lower platform of the X-shaped lifting mechanism, and the other end is connected to the connecting rod. The micro motor (305) drives the slider (304) to change position to adjust the stiffness of the diaphragm spring (302). The electric push rod (307) drives the X-shaped lifting platform to achieve active leveling and ensures that the position is stable after adjustment through self-locking characteristics.

4. The ultra-precision integrated active and passive piezoelectric vibration isolation platform for optical collimation according to claim 1, characterized in that, The horizontal vibration isolation device consists of eight superstructure passive vibration reduction units (11), with four arranged symmetrically in the X and Y directions; the superstructure passive vibration reduction unit (11) is composed of 24 groups of local resonance structure arrays, and each local resonance structure includes two compliant elastic beams (401) and a lead block oscillator (402).

5. The ultra-precision integrated active and passive piezoelectric vibration isolation platform for optical collimation according to claim 1, characterized in that, There are eight piezoelectric ceramic actuators in total, four in the vertical direction and four in the horizontal direction. The lower end of the vertical piezoelectric ceramic actuator (10) is reserved with the base (6) and the upper end is connected to the lower surface of the upper bearing platform. The horizontal piezoelectric ceramic actuator (12) is directly installed on the lower surface of the upper bearing platform.

6. The ultra-precision integrated active and passive piezoelectric vibration isolation platform for optical collimation according to claim 1, characterized in that, The two-dimensional acoustic black hole damping enhancement structure (7) consists of a two-dimensional acoustic black hole damper (501) and a damping material layer (502), and is used to absorb the mid-to-high frequency vibrations remaining in the upper bearing platform after the active and passive vibration isolation system.

7. The ultra-precision integrated active and passive piezoelectric vibration isolation platform for optical collimation according to claim 1, characterized in that, The limiting device (8) consists of four sets of cylinders. The cylinders are fixed to the lower surface of the upper bearing platform and the base (6) by bolts, and a gap is reserved between them. Under abnormal working conditions, the limiting device (8) limits the vertical and horizontal displacement of the upper bearing platform to a safe range through mechanical contact.

8. The ultra-precision integrated active and passive piezoelectric vibration isolation platform for optical collimation according to claim 1, characterized in that, Four laser displacement sensors (9) and eight acceleration sensors (13) are provided. The sensor output signals are first amplified by the operational amplifier of the conditioning circuit, and then connected to the control unit through the multiplexer to realize efficient centralized acquisition of multiple signals. The control unit combines the two sensor signals to perform composite active control, driving the piezoelectric ceramic actuator to generate a canceling force that is equal in magnitude and opposite in direction to the vibration interference.

9. The ultra-precision integrated active and passive piezoelectric vibration isolation platform for optical collimation according to claim 1, characterized in that, The platform is equipped with a load adaptive mechanism. The load quality is sensed in real time through the extension and retraction of the electric push rod (307) and the feedback of the potentiometer. The potentiometer signal is collected by the ADC port of the control unit after being switched by the multiplexer. The control unit adjusts the system stiffness to keep the natural frequency of the passive vibration isolation system stable under different loads. The entire platform is made of aluminum alloy.

10. The ultra-precision integrated active and passive piezoelectric vibration isolation platform for optical collimation according to claim 1, characterized in that, By changing the control algorithm parameters, the low-to-medium frequency vibration interference can be reduced. By changing the structural parameters of the superstructure passive vibration reduction unit (11) and the stiffness of the diaphragm spring (302), the passive vibration reduction requirements of different low-to-medium frequency vibration interferences can be adapted.

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