A bilateral double-drive symmetric decoupling flexible device for piezoelectric stick-slip positioning

Abstract

This invention belongs to the field of piezoelectric stick-slip precision positioning technology, specifically relating to a dual-sided, dual-drive, symmetrically decoupled flexible device for piezoelectric stick-slip positioning. It includes a frame base, a flexible mechanism fixed base, a mover, two sets of piezoelectric drive units, and a dual-sided symmetrically decoupled flexible mechanism. The dual-sided symmetrically decoupled flexible mechanism includes a first flexible mechanism and a second flexible mechanism symmetrically arranged. The first and second flexible mechanisms are respectively connected to the corresponding piezoelectric drive units and the frame base, and transmit the driving force of the piezoelectric drive units to the mover to drive the mover to reciprocate along a straight line. This invention adopts a dual-sided symmetrical piezoelectric drive structure, with the two sets of piezoelectric drive units operating synchronously, applying symmetrical driving forces to the mover. This fundamentally cancels out the lateral component force and torsional torque generated by single-sided drive, effectively suppressing parasitic motion, ensuring pure linear motion of the mover, and significantly improving positioning accuracy and operational stability.

Description

Technical Field

[0001] This invention belongs to the field of piezoelectric stick-slip precision positioning technology, specifically relating to a dual-sided dual-drive symmetrical decoupling flexible device for piezoelectric stick-slip positioning. Background Technology

[0002] Piezoelectric stick-slip actuators have been widely used in precision positioning and micro-manipulation due to their advantages such as compact structure, high positioning resolution, and fast response speed. However, existing piezoelectric stick-slip actuators generally adopt a combination of a single-sided single piezoelectric actuator and a conventional flexible component, which has several common technical shortcomings.

[0003] First, the inertial impact force from a single-sided drive output generates eccentric loads and torsional moments, causing parasitic movements such as pitching and lateral shifting in the flexible mechanism. This results in strong motion coupling, severely disrupting the smoothness of the piezoelectric stick-slip alternating "adhesion-sliding" process and directly reducing the repeatability of positioning. Second, the limited output capacity of a single drive unit and the inability to superimpose driving forces restrict the potential for increasing step length, making it difficult to simultaneously meet the positioning requirements of large stroke and high efficiency. Third, unilateral force leads to localized stress concentration in the flexible structure, causing unilateral wear on the contact surface. Under long-term high-frequency reciprocating operation, the fatigue life of the mechanism is significantly shortened, and the positioning performance continues to deteriorate.

[0004] Furthermore, most existing flexible drive mechanisms adopt an integral embedded mounting structure, secured by tight fit or multiple sets of screws. When the flexible component exhibits fatigue deformation, surface wear, or requires replacement with a flexible component of different stiffness specifications, the entire motor must be completely disassembled. This disassembly and reassembly process is cumbersome, complex, time-consuming, and labor-intensive. During disassembly and reassembly, the internal fit of the motor is easily disturbed, disrupting the friction pair state between the mover and the flexible component, as well as the original assembly reference. After reassembly, repeated precision calibration and drive parameter adjustments are required, which not only increases maintenance costs but also easily leads to a decline in overall machine performance.

[0005] Therefore, this invention is proposed. Summary of the Invention

[0006] To address the technical problems existing in the prior art, the present invention provides a double-sided symmetrical decoupling flexible device for piezoelectric stick-slip positioning that can achieve enhanced driving force, motion decoupling, uniform stress distribution, and easy independent assembly and disassembly.

[0007] To achieve the above objectives, the present invention adopts the following technical solution: A dual-sided dual-drive symmetrical decoupling flexible device for piezoelectric stick-slip positioning includes a frame base, a flexible mechanism fixing base, a mover, two sets of piezoelectric drive units, and a dual-sided symmetrical decoupling flexible mechanism. The frame base is mounted on a flexible mechanism fixed base; the mover is slidably disposed on the frame base; two sets of piezoelectric drive units are symmetrically disposed on both sides of the mover; The dual-sided symmetrical decoupling flexible mechanism includes a first flexible mechanism and a second flexible mechanism arranged symmetrically; the first flexible mechanism and the second flexible mechanism are respectively connected to the corresponding piezoelectric drive unit and the frame base, and transmit the driving force of the piezoelectric drive unit to the mover to drive the mover to reciprocate along a straight line; The two sets of piezoelectric drive units are configured to operate synchronously, and apply symmetrical driving force to the mover through the bilateral symmetrical decoupling flexible mechanism to counteract the lateral component force and torsional torque.

[0008] The bilaterally symmetrical decoupling flexible mechanism is an integrated closed-loop structure. Its outer ring is connected to the frame base, and its inner ring is connected to the mover. Flexible support arms are symmetrically arranged on the bilaterally symmetrical decoupling flexible mechanism along the movement direction of the mover.

[0009] The piezoelectric drive unit includes a piezoelectric ceramic and a friction head; one end of the piezoelectric ceramic is connected to the frame base, and the other end is connected to the friction head through the double-sided symmetrical decoupling flexible mechanism; the friction head forms a friction contact surface with the side wall of the mover to drive the mover through stick-slip motion.

[0010] One set of the piezoelectric drive units includes two piezoelectric ceramics arranged in parallel to increase the output thrust.

[0011] The moving part includes a platform and a driven shaft of a cross roller guide rail disposed on both sides of the platform; the frame base is provided with a fixed shaft of the cross roller guide rail that cooperates with the driven shaft of the cross roller guide rail.

[0012] The flexible mechanism fixing base is provided with a detachably connected flexible mechanism body, which integrates piezoelectric ceramics and a friction head for contacting the moving part; wherein, a quick-release structure is provided between the flexible mechanism body and the flexible mechanism fixing base.

[0013] The quick-release structure includes a guide assembly, a circumferential limiting assembly, and an independent quick-release locking assembly; The guiding component includes a guide groove disposed on the flexible mechanism fixing base and a guide boss disposed on the flexible mechanism body. The guiding component is configured to guide the flexible mechanism body to be inserted into or withdrawn from the flexible mechanism fixing base in a straight line. The circumferential limiting component includes a limiting slot disposed on the fixed base of the flexible mechanism and a limiting boss disposed on the body of the flexible mechanism; when the body of the flexible mechanism is installed in place, the limiting boss engages with the limiting slot to limit the circumferential position of the body of the flexible mechanism. The independent quick-release locking assembly includes several fixing holes, and the flexible mechanism body is locked to the flexible mechanism fixing base through the fixing holes.

[0014] A pre-tightening mechanism is provided between the flexible mechanism body and the flexible mechanism fixed base. The pre-tightening mechanism includes a fine-tuning screw or a wedge block assembly for adjusting the normal pre-tightening force of the friction head on the moving part.

[0015] The bilaterally symmetrical decoupled flexible mechanism includes a synchronization control module, which is electrically connected to the two sets of piezoelectric drive units and is used to output drive signals with the same phase and amplitude to the two sets of piezoelectric drive units.

[0016] The synchronization control module includes a host computer / main control terminal, a main controller, a digital-to-analog converter module, and a high-voltage power amplifier; The host computer / main control terminal is used for macro trajectory planning, parameter configuration and system status monitoring; The main controller is responsible for executing the underlying control algorithm, waveform generation, and real-time signal processing. The digital-to-analog converter module is used to convert the digital control signal output by the main controller into a continuous analog voltage signal; The high-voltage power amplifier is used to linearly amplify the low-voltage analog signal output by the DAC to the high-voltage drive signal required by the piezoelectric actuator and provide sufficient drive current.

[0017] The beneficial effects of this invention are as follows: (1) This application adopts a dual-sided symmetrical dual piezoelectric drive structure. The two sets of piezoelectric drive units operate synchronously and apply symmetrical driving force to the mover, which fundamentally cancels the lateral component force and torsional torque generated by the single-sided drive, effectively suppresses parasitic motion, ensures the pure linear motion of the mover, and significantly improves the positioning accuracy and running stability. (2) The driving forces of the dual-side drive units are synchronously superimposed, which can achieve a larger single step and output thrust under the same driving conditions, taking into account the positioning requirements of large stroke and high efficiency, and enhancing the system's adaptability to heavy loads; symmetrical force distribution makes the load evenly distributed on the entire flexible part and contact surface, which completely improves the problem of local stress concentration and contact surface wear on the single-side structure, extends the fatigue life of the mechanism under high frequency reciprocating working conditions, and ensures the consistency of performance throughout the entire life cycle. (3) This application designs the flexible mechanism as a modular structure that can be independently disassembled and assembled. Through the guide component, circumferential limit component and independent quick-release locking component, the flexible mechanism body can be quickly and accurately positioned and locked. When maintaining or replacing, there is no need to disassemble the core components of the motor, which greatly simplifies the disassembly and assembly process, improves the assembly and maintenance efficiency, and reduces the operation and maintenance cost and technical threshold. By setting a pre-tightening mechanism, the normal pre-tightening force of the friction head on the mover can be adjusted, ensuring the consistency of the contact state of the two-sided friction pair, and further improving the smoothness of the movement and the positioning accuracy. Attached Figure Description

[0018] Figure 1 This is a schematic diagram of the structure of a single-sided piezoelectric stick-slip drive motor in the prior art; Figure 2 This is a schematic diagram of the structure of a dual-sided, dual-drive, symmetrically decoupled flexible device for piezoelectric stick-slip positioning according to the present invention. Figure 1 ; Figure 3 This is a schematic diagram of the structure of a dual-sided, dual-drive, symmetrically decoupled flexible device for piezoelectric stick-slip positioning according to the present invention. Figure 2 ; Figure 4 This is a partial structural diagram of a dual-sided, dual-drive, symmetrically decoupled flexible device for piezoelectric stick-slip positioning according to the present invention. Figure 1 ; Figure 5 This is a partial structural diagram of a dual-sided, dual-drive, symmetrically decoupled flexible device for piezoelectric stick-slip positioning according to the present invention. Figure 2 ; Figure 6 This is a partial structural diagram of a dual-sided, dual-drive, symmetrically decoupled flexible device for piezoelectric stick-slip positioning according to the present invention. Figure 3 ; Figure 7 This is a partial structural diagram of a dual-sided, dual-drive, symmetrically decoupled flexible device for piezoelectric stick-slip positioning according to the present invention. Figure 4 ; Figure 8 This is a partial structural diagram of a dual-sided, dual-drive, symmetrically decoupled flexible device for piezoelectric stick-slip positioning according to the present invention. Figure 5 ; Figure 9 This is a partial structural diagram of a dual-sided, dual-drive, symmetrically decoupled flexible device for piezoelectric stick-slip positioning according to the present invention. Figure 6 ; Figure 10 This is a partial structural diagram of a dual-sided, dual-drive, symmetrically decoupled flexible device for piezoelectric stick-slip positioning according to the present invention. Figure 7 ; The components are labeled as follows: 1. Friction head; 2. Piezoelectric ceramic; 3. Pre-tightening mechanism; 4. Fixed hole; 5. Decoupling flexible mechanism; 6. Cross roller guide fixed shaft; 7. Cross roller guide driven shaft; 8. Flexible mechanism fixed base; 9. Stage; 10. Frame base. Detailed Implementation

[0019] The present invention will be further described below with reference to specific embodiments.

[0020] In the following description, all directional (or orientational) concepts involving up, down, left, right, front, and back refer to the position of the figure being described, and are intended to facilitate public understanding. Therefore, they should not be construed as a special limitation on the technical solution provided by this invention.

[0021] like Figures 2-10 As shown, a dual-sided dual-drive symmetrical decoupling flexible device for piezoelectric stick-slip positioning includes a frame base 10, a flexible mechanism fixing base 8, a mover, two sets of piezoelectric drive units, and a dual-sided symmetrical decoupling flexible assembly 5. The frame base 10 is mounted on the flexible mechanism fixing base 8. The mover is slidably disposed on the frame base 10. The two sets of piezoelectric drive units are symmetrically disposed on both sides of the mover. The dual-sided symmetrical decoupling flexible mechanism 5 includes a first flexible mechanism and a second flexible mechanism symmetrically disposed. The first flexible mechanism and the second flexible mechanism respectively connect the corresponding piezoelectric drive unit to the frame base 10 and transmit the driving force of the piezoelectric drive unit to the mover to drive the mover to reciprocate along a straight line. The two sets of piezoelectric drive units are configured to operate synchronously, applying symmetrical driving forces to the mover through the bilaterally symmetrical decoupling flexible mechanism 5 to counteract lateral forces and torsional torques. The bilaterally symmetrical decoupling flexible mechanism 5 is an integrated closed-loop structure, with its outer ring connected to the frame base 10 and its inner ring connected to the mover. Flexible support arms are symmetrically arranged on the bilaterally symmetrical decoupling flexible mechanism 5 along the movement direction of the mover.

[0022] The piezoelectric drive unit includes a piezoelectric ceramic 2 and a friction head 1. One end of the piezoelectric ceramic 2 is connected to the frame base 10, and the other end is connected to the friction head 1 through a double-sided symmetrical decoupling flexible mechanism 5. The friction head 1 forms a friction contact surface with the side wall of the mover to drive the mover through stick-slip motion. One set of piezoelectric drive units includes two piezoelectric ceramics 2 arranged in parallel to increase the output thrust. The mover includes a stage 9 and crossed roller guide driven shafts 7 arranged on both sides of the stage 9. The frame base 10 is provided with a crossed roller guide fixed shaft 6 that cooperates with the crossed roller guide driven shaft 7.

[0023] The flexible mechanism fixing base 8 is equipped with a detachably connected flexible mechanism body, which integrates a piezoelectric ceramic 2 and a friction head 1 for contacting the moving element. A quick-release structure is provided between the flexible mechanism body and the flexible mechanism fixing base 8. The quick-release structure includes a guide assembly, a circumferential limiting assembly, and an independent quick-release locking assembly. The guide assembly includes a guide groove on the flexible mechanism fixing base 8 and a guide boss on the flexible mechanism body. The guide assembly is configured to guide the flexible mechanism body to insert into or withdraw from the flexible mechanism fixing base 8 in a straight line. The circumferential limiting assembly includes a limiting slot on the flexible mechanism fixing base 8 and a limiting boss on the flexible mechanism body. When the flexible mechanism body is installed in place, the limiting boss engages with the limiting slot to limit the circumferential position of the flexible mechanism body. The independent quick-release locking assembly includes several fixing holes 4 through which the flexible mechanism body is locked to the flexible mechanism fixing base 8. A pre-tightening mechanism 3 is provided between the flexible mechanism body and the flexible mechanism fixed base 8. The pre-tightening mechanism 3 includes a fine-tuning screw or wedge block assembly, which is used to adjust the normal pre-tightening force of the friction head 1 on the moving part.

[0024] The dual-sided symmetrical decoupled flexible mechanism 5 includes a synchronization control module, which is electrically connected to two sets of piezoelectric drive units and is used to output drive signals with the same phase and amplitude to the two sets of piezoelectric drive units. The synchronization control module includes a host computer / main control terminal, a main controller, a digital-to-analog converter module, and a high-voltage power amplifier; the host computer / main control terminal is used for macroscopic trajectory planning, parameter configuration, and system status monitoring; the main controller is responsible for executing the underlying control algorithm, waveform generation, and real-time signal processing; the digital-to-analog converter module is used to convert the digital control signal output by the main controller into a continuous analog voltage signal; the high-voltage power amplifier is used to linearly amplify the low-voltage analog signal output by the DAC to the high-voltage drive signal required by the piezoelectric actuator and provide sufficient drive current.

[0025] Example 1: Overall Structure of a Bilaterally Symmetrical Decoupling Flexible Mechanism like Figure 2 and Figure 3 As shown in the figure, this embodiment describes in detail the overall structure of a double-sided symmetrical decoupling flexible mechanism for piezoelectric stick-slip positioning.

[0026] The mechanism adopts a fully closed-loop rigid fixed structure at the lower end, mainly including a fixed base, a piezoelectric drive module on the left, a piezoelectric drive module on the right, and a moving platform in the middle.

[0027] Fixed base: It is a closed-loop rigid frame with the lower end completely sealed. Its bottom is completely fixed and there is no slight slippage, providing a stable installation reference for the entire mechanism.

[0028] The left-side piezoelectric drive module comprises two piezoelectric ceramics 2 arranged in parallel to increase the output thrust. The rear end of the piezoelectric ceramics 2 is rigidly connected to the left side of the fixed base via a fixing hole 4. Its front end is connected to a decoupling flexible mechanism 5, and the output end of the decoupling flexible mechanism 5 is equipped with a friction head 1.

[0029] Right-side piezoelectric drive module: Completely mirror-symmetrical to the left side, containing two piezoelectric ceramics 2, mounted on the right side of the base via fixing holes 4. Its front end is connected to a decoupling flexible mechanism 5, and its output end is equipped with a friction head 1.

[0030] The combined driving force of the dual drive units significantly increases the single-step amount of the motor under the same electrical conditions, improving feed efficiency and simultaneously meeting the needs of micro-strokes (1mm-2mm) and nanometer-level positioning. The combination of symmetrical drive and symmetrical flexible structure effectively eliminates eccentric loads and parasitic motions, resulting in a smooth and shock-free stick-slip switching process and greatly improving the repeatability and stability of the motor. The uniform force design across the entire range avoids uneven wear on the contact surface and stress concentration in flexible parts, mitigating fatigue damage and extending the overall service life of the motor under high-frequency reciprocating conditions. The compact structure of the whole machine retains the advantages of piezoelectric motors, such as small size, no electromagnetic interference, and rapid response, and can be directly adapted to linear feed scenarios of various precision equipment, demonstrating strong versatility and industrialization capabilities.

[0031] The central moving platform includes a fixed cross roller guide shaft 6 and a driven cross roller guide shaft 7. The fixed shaft is connected to an external load or base, and the driven shaft acts as the moving part, with its left and right side surfaces forming large-area lateral surface contact with the friction head 1.

[0032] Working principle: The control system inputs perfectly synchronized asymmetric sawtooth wave voltage signals to the piezoelectric ceramics 2 on the left and right sides.

[0033] The viscous phase (slow push): The two piezoelectric ceramics 2 on both sides extend synchronously and slowly, causing the decoupled flexible mechanisms 5 on both sides to undergo elastic deformation and store potential energy, pushing the two friction heads 1 forward synchronously. At this time, the friction heads 1 on both sides and the driven shaft 7 of the crossed roller guide remain relatively stationary due to static friction, causing the driven shaft and the entire load to generate micro-displacements synchronously. Due to the symmetrical force exerted on both sides, the lateral component force and the torsional torque cancel each other out, and the driven shaft only produces pure linear translation, without parasitic movements such as pitch or yaw.

[0034] Sliding Phase (Rapid Return): The piezoelectric ceramic 2 rapidly retracts and resets, while the decoupled flexible mechanism 5 rapidly releases its potential energy. Due to the extremely high return acceleration, the generated inertial force overcomes the maximum static friction force on the contact surface, and the two friction heads 1 rapidly slide backward and reset on the driven shaft surface. At this time, the driven shaft remains stationary or experiences only a very slight retraction due to its own and the load's inertia.

[0035] The two stages described above are repeated in a cycle to achieve cumulative linear positioning with large step sizes at the nanometer level.

[0036] Example 2: Flexible mechanism module that can be quickly assembled and disassembled This embodiment, based on Embodiment 1, further describes in detail the flexible mechanism module that can be quickly assembled and disassembled.

[0037] This module designs the flexible mechanism as an independent assembly unit, including the flexible mechanism body and the flexible mechanism fixing base 8.

[0038] Flexible mechanism body: integrates piezoelectric ceramic 2 and friction head 1, serving as the core drive and transmission component. Flexible mechanism fixing base 8: fixedly installed on the frame base 10, serving as the mounting carrier for the flexible mechanism body.

[0039] The specific structure is as follows: To enable independent, rapid, and high-precision assembly and disassembly of the flexible mechanism body, a combination structure of "positioning slot + guide component + independent quick-release locking component" is adopted between the two.

[0040] Guiding component: A linear guide groove is provided on the mounting surface of the flexible mechanism fixing base 8, and a guide boss that slides in conjunction with the guide groove is provided on the corresponding outer side wall of the flexible mechanism body. This component defines the linear insertion and removal trajectory of the flexible mechanism body, ensuring that there is no lateral squeezing or bumping during the assembly and disassembly process.

[0041] Circumferential limiting structure: The flexible mechanism fixing base 8 is provided with a circumferential limiting slot, and the flexible mechanism body is provided with a matching circumferential limiting boss. When the flexible mechanism body is pushed into place, the boss and the slot are precisely engaged, limiting its final installation position and ensuring the consistency of position during multiple disassembly and assembly.

[0042] Independent quick-release locking assembly: A simple locking structure (such as a screw) passes through the fixing hole 4 and acts on the locking surface to achieve one-click or single-step locking / releasing, greatly simplifying the disassembly and assembly operation.

[0043] Assembly and disassembly process: Assembly: Push the flexible mechanism body straight into the flexible mechanism fixing base 8 along the guide groove until the circumferential limiting boss automatically slides into the limiting slot to achieve high-precision alignment. Finally, lock it through the fixing hole 4 (e.g.) Figure 5 ).

[0044] Disassembly: Simply loosen the quick-release locking components at the four fixing holes to release the locking force, then grasp the flexible mechanism body and pull it backward along the guide assembly. The entire process does not require disassembling core moving parts such as the central mover (e.g., Figure 4 ).

[0045] Example 3: Preload Adjustment and Symmetrical Layout on Both Sides This embodiment, based on embodiment 2, further demonstrates the details of the preload adjustment mechanism and the bilateral symmetrical layout.

[0046] Pre-tightening mechanism 3: A pre-tightening mechanism 3, such as a fine-tuning screw or wedge block assembly, is provided between the flexible mechanism body and the flexible mechanism fixed base 8. By adjusting the pre-tightening mechanism 3, the lateral position of the flexible mechanism body can be precisely changed, thereby adjusting the normal pre-tightening force of the friction head 1 on the moving part, ensuring that the contact state and friction force of the two-sided friction pair are consistent.

[0047] Symmetrical layout on both sides: This embodiment shows a complete piezoelectric stick-slip motor structure, including a frame base 10, a first drive assembly and a second drive assembly symmetrically installed on its left and right sides, and a platform 9 located between the two and supported by cross roller guides.

[0048] Left-side drive assembly: includes a decoupling flexible mechanism 5, a flexible mechanism fixing base 8, a friction head 1, and two piezoelectric ceramics 2.

[0049] The right-side drive assembly includes a decoupling flexible mechanism 5, a flexible mechanism fixing base 8, a friction head 1, and two piezoelectric ceramics 2.

[0050] Crossed roller guide: The left guide assembly includes a fixed cross roller guide shaft 6 and a driven cross roller guide shaft 7; the right guide assembly includes a fixed cross roller guide shaft 6 and a driven cross roller guide shaft 7. The stage 9 rolls on the fixed shaft via the driven shafts on both sides, achieving high-precision linear motion.

[0051] Working principle and decoupling process: The synchronous control module of the motor outputs asymmetric sawtooth wave drive signals with the same frequency, phase, and amplitude to the piezoelectric ceramics 2 on both sides. During the adhesion stage, the piezoelectric ceramics 2 on both sides extend synchronously and slowly, pushing the two friction heads 1 forward synchronously. Due to the symmetrical layout on both sides, the thrust generated on both sides is equal in magnitude, opposite in direction, and collinear, perfectly canceling out the lateral force and torsional torque, achieving mechanical decoupling, and the stage 9 is pushed smoothly. During the sliding stage, the piezoelectric ceramics 2 on both sides retract synchronously and quickly, and the friction heads 1 slide backward and reset quickly on the surface of the stage 9. The stage 9 maintains its position by inertia, completing a single linear step.

[0052] Example 4: Synchronization Control Module This embodiment describes the synchronization control module that drives the aforementioned mechanism. This module is electrically connected to two sets of piezoelectric drive units and is used to output drive signals with the same phase and amplitude. Its hardware architecture, from top to bottom, mainly includes: First, the host computer / main control terminal is used for macro trajectory planning, parameter configuration (such as target displacement and running speed), and system status monitoring, and to issue comprehensive control commands.

[0053] Next, the main controller, as the core computing unit of the system (such as FPGA / DSP / MCU), is responsible for executing low-level control algorithms, waveform generation, and real-time signal processing. Internally, it generates high-precision asymmetric sawtooth wave digital control signals with "slow rise and fast fall" characteristics, and employs a hardware-level clock synchronization mechanism to ensure strict consistency in amplitude, phase, and timing of the drive signals on both sides. It also introduces an envelope smoothing control strategy and a feedforward compensation algorithm to handle the smooth transition during start-up and shutdown phases and the low-voltage dead-zone nonlinearity of piezoelectric materials.

[0054] Subsequently, the digital-to-analog converter (DAC) module converts the digital control signal output by the main controller into a continuous low-voltage analog signal with high fidelity.

[0055] Then, the high-voltage power amplifier linearly amplifies the low-voltage analog signal (such as 0-5V) output by the DAC to the high-voltage drive signal (such as 0-150V or higher) required by the piezoelectric actuator, and provides sufficient drive current.

[0056] Ultimately, the piezoelectric actuators on the left and right sides alternately perform viscous and sliding motions under the strict synchronization of high-voltage signals. The symmetrical thrust generated by these actuators effectively counteracts the lateral force and torsional torque, enabling the central moving platform to achieve high-precision, high-stability nanometer-level large-step cumulative linear positioning.

[0057] Comparative Example: High-precision single-sided piezoelectric stick-slip drive unit module like Figure 1 The base is used as a rigid support foundation with mounting holes at the bottom. A drive source and pre-tightening system are used to place the piezoelectric ceramic 2 horizontally in the base groove. A fixing device at the rear end provides pre-tightening force to ensure zero transmission gap. A parallel flexible mechanism is used, namely a cross beam structure, connected to the front end of the piezoelectric ceramic 2. The flexible mechanism is fixed to the base by fixing screws, and the initial stiffness can be finely adjusted. The friction output end is located at the front end of the flexible mechanism and is in direct contact with the moving platform.

[0058] When a sawtooth wave voltage is applied, the single-sided structure pushes the friction head 1 to achieve stick-slip motion through a flexible mechanism. However, since the force is applied only on one side, the line of action of the driving force deviates from the center of mass of the load, which inevitably generates an eccentric torque, causing the friction head 1 to slip laterally and fluctuate in normal pressure at the contact surface.

[0059] In contrast, this application introduces a dual-sided symmetrical drive design, fundamentally overcoming the inherent defects of existing technologies such as uneven force distribution, susceptibility to parasitic motion, and limited load capacity. Specifically, in Practical Example 1, a self-balancing mechanical model is constructed by using the mirror-symmetrical arrangement of the piezoelectric ceramics 2 on both sides and the decoupled flexible mechanism 5. This allows the horizontal driving force vector to be superimposed while canceling out the lateral component force and torsional torque, completely eliminating parasitic motions such as pitch and yaw caused by off-center loading, ensuring pure linear motion components and nanometer-level positioning accuracy at the output end. At the same time, the dual-sided parallel drive not only doubles the theoretical output thrust, significantly enhancing the system's adaptability to heavy loads and dynamic response speed, but also improves the overall structural stiffness and anti-interference capability through a closed force flow loop. Furthermore, symmetrical force distribution ensures the uniform distribution of contact pressure between the friction head 1 and the crossed roller guide, effectively avoiding unilateral wear, extending the service life of core components, and ensuring performance consistency throughout the entire life cycle.

[0060] It should be noted that the device structure and accompanying drawings of this invention mainly describe the principle of this invention. In terms of the technical aspects of this design principle, the setting of the power mechanism, power supply system and control system of the device is not fully described. However, those skilled in the art can clearly understand the specifics of its power mechanism, power supply system and control system if they understand the principle of the invention. The control method in the application document is automatic control through a controller. The control circuit of the controller can be implemented by those skilled in the art through simple programming.

[0061] Although embodiments of the invention have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions, and variations can be made to these embodiments, or they can be used directly or indirectly, without departing from the principles and spirit of the invention. In other related technical fields, the scope of the invention is defined by the appended claims and their equivalents, and they are similarly included within the scope of patent protection of the invention.

Claims

1. A dual-sided, dual-drive, symmetrically decoupled flexible device for piezoelectric stick-slip positioning, characterized in that: It includes a frame base, a flexible mechanism fixed base, a mover, two sets of piezoelectric drive units, and a bilaterally symmetrical decoupled flexible mechanism; The flexible mechanism is fixed on the frame base; the mover is slidably disposed on the frame base; two sets of piezoelectric drive units are symmetrically disposed on both sides of the mover; The dual-sided symmetrical decoupling flexible mechanism includes a first flexible mechanism and a second flexible mechanism arranged symmetrically; the first flexible mechanism and the second flexible mechanism are respectively connected to the corresponding piezoelectric drive unit and the frame base, and transmit the driving force of the piezoelectric drive unit to the mover to drive the mover to reciprocate along a straight line; The two sets of piezoelectric drive units are configured to operate synchronously, and apply symmetrical driving force to the mover through the bilateral symmetrical decoupling flexible mechanism to counteract the lateral component force and torsional torque.

2. The dual-sided dual-drive symmetrical decoupling flexible device for piezoelectric stick-slip positioning as described in claim 1, characterized in that: The bilaterally symmetrical decoupling flexible mechanism is an integrated closed-loop structure. Its outer ring is connected to the frame base, and its inner ring is connected to the mover. Flexible support arms are symmetrically arranged on the bilaterally symmetrical decoupling flexible mechanism along the movement direction of the mover.

3. The double-sided, dual-drive, symmetrically decoupled flexible device for piezoelectric stick-slip positioning as described in claim 1, characterized in that: The piezoelectric drive unit includes a piezoelectric ceramic and a friction head; one end of the piezoelectric ceramic is connected to the frame base, and the other end is connected to the friction head through the double-sided symmetrical decoupling flexible mechanism; the friction head forms a friction contact surface with the side wall of the mover to drive the mover through stick-slip motion.

4. The dual-sided dual-drive symmetrical decoupling flexible device for piezoelectric stick-slip positioning as described in claim 3, characterized in that: One set of the piezoelectric drive units includes two piezoelectric ceramics arranged in parallel to increase the output thrust.

5. The bilaterally symmetrical decoupling flexible mechanism for piezoelectric stick-slip positioning as described in claim 1, characterized in that: The moving part includes a platform and a driven shaft of a cross roller guide rail disposed on both sides of the platform; the frame base is provided with a fixed shaft of the cross roller guide rail that cooperates with the driven shaft of the cross roller guide rail.

6. The double-sided, dual-drive, symmetrically decoupled flexible device for piezoelectric stick-slip positioning as described in claim 1, characterized in that: The flexible mechanism fixing base is provided with a detachably connected flexible mechanism body, which integrates piezoelectric ceramics and a friction head for contacting the moving part; wherein, a quick-release structure is provided between the flexible mechanism body and the flexible mechanism fixing base.

7. The dual-sided dual-drive symmetrical decoupling flexible device for piezoelectric stick-slip positioning as described in claim 6, characterized in that: The quick-release structure includes a guide assembly, a circumferential limiting assembly, and an independent quick-release locking assembly; The guiding component includes a guide groove disposed on the flexible mechanism fixing base and a guide boss disposed on the flexible mechanism body. The guiding component is configured to guide the flexible mechanism body to be inserted into or withdrawn from the flexible mechanism fixing base in a straight line. The circumferential limiting component includes a limiting slot disposed on the fixed base of the flexible mechanism and a limiting boss disposed on the body of the flexible mechanism; when the body of the flexible mechanism is installed in place, the limiting boss engages with the limiting slot to limit the circumferential position of the body of the flexible mechanism. The independent quick-release locking assembly includes several fixing holes, and the flexible mechanism body is locked to the flexible mechanism fixing base through the fixing holes.

8. A dual-sided, dual-drive, symmetrically decoupled flexible device for piezoelectric stick-slip positioning as described in claim 6 or 7, characterized in that: A pre-tightening mechanism is provided between the flexible mechanism body and the flexible mechanism fixed base. The pre-tightening mechanism includes a fine-tuning screw or a wedge block assembly for adjusting the normal pre-tightening force of the friction head on the moving part.

9. The double-sided, dual-drive, symmetrically decoupled flexible device for piezoelectric stick-slip positioning as described in claim 1, characterized in that: It includes a synchronization control module, which is electrically connected to the two sets of piezoelectric drive units and is used to output drive signals with the same phase and amplitude to the two sets of piezoelectric drive units.

10. The dual-sided dual-drive symmetrical decoupling flexible device for piezoelectric stick-slip positioning as described in claim 9, characterized in that: The synchronization control module includes a host computer / main control terminal, a main controller, a digital-to-analog converter module, and a high-voltage power amplifier; The host computer / main control terminal is used for macro trajectory planning, parameter configuration and system status monitoring; The main controller is responsible for executing the underlying control algorithm, waveform generation, and real-time signal processing. The digital-to-analog converter module is used to convert the digital control signal output by the main controller into a continuous analog voltage signal; The high-voltage power amplifier is used to linearly amplify the low-voltage analog signal output by the DAC to the high-voltage drive signal required by the piezoelectric actuator and provide sufficient drive current.

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