A precision probe manipulator with adjustable stiffness in motion direction

Abstract

The application discloses a precision probe operator with adjustable motion direction stiffness, comprising a variable motion direction stiffness flexible micro-motion platform, wherein a square hole table is arranged at the center position of the platform, a composite parallel guide flexible component is arranged at the first opposite side of the square hole table, the composite parallel guide flexible component is connected with the square hole table through a curved beam, and a guide beam flexible component is arranged at the second opposite side of the square hole table. The guide beam is connected with the square hole table through a square rod. The end of the square rod at one side of the second opposite side of the square hole table is provided with a bridge type amplification flexible component. A rhombic clamping stiffness adjusting mechanism is arranged at the center position of the platform, wherein a voice coil motor driver is arranged at the center position, a voice coil motor mounting plate is arranged at the first opposite side of the center position, a stator and a rotor of the voice coil motor are fixed on the voice coil motor mounting plate respectively, a mounting column is arranged at the second opposite side of the center position, and the voice coil motor mounting plate and the mounting column are connected through flexible plate springs with equal thickness.

Description

Technical Field

[0001] This invention relates to the field of precision probe manipulation technology, and in particular to a precision probe manipulator with adjustable motion direction stiffness. Background Technology

[0002] Probe manipulators are key actuators in the field of micro-nano manipulation, particularly valuable in semiconductor device fabrication, assembly, and testing; biological cell injection, separation, and extraction; and surface probing and inspection of small parts. Current technologies for precision probe manipulators often employ a combination of flexible mechanisms and piezoelectric ceramic actuators to achieve high-precision positioning and scanning motion. Furthermore, they typically rely on control algorithms to manage a single actuator for active stiffness adjustment. This leads to increasingly complex control algorithms, reduced stability, and a failure to separate displacement and stiffness driving, thus hindering the creation of simpler and faster force-displacement precision probe manipulation tasks. Additionally, the non-adjustable motion direction stiffness of traditional precision probe manipulators can result in probe scratches or damage to the manipulated object, further compromising the safety of the precision probe manipulator.

[0003] In the existing patent CN202211031341.6, a three-dimensional micro-positioning platform driven by piezoelectric ceramics is disclosed, but this patent cannot achieve real-time adjustment of stiffness in the direction of motion; in the existing patent CN202211310681.2, a single-degree-of-freedom composite-driven adjustable stiffness micro-motion platform is disclosed. The method of stiffness adjustment in this patent is to utilize the electromagnetic adjustable negative stiffness of Maxwell normal stress, but the electromagnetic adjustable negative stiffness introduced in this patent is prone to generating eddy current effects, which reduces the efficiency of the stiffness adjustment system.

[0004] Traditional variable stiffness actuators can adjust the stiffness in the direction of motion, but precision probe manipulators usually require very precise operations. Traditional variable stiffness actuators have assembly problems such as gaps and friction that seriously affect accuracy, which limits their application in precision probe operations. Summary of the Invention

[0005] In view of the shortcomings of the existing technology, the purpose of this invention is to provide a precision probe manipulator with adjustable motion direction stiffness. It can further adjust the stiffness of the probe motion direction in real time while ensuring the precision motion of the probe manipulator, thereby achieving accurate control of the probe operating force.

[0006] To achieve the above objectives, the present invention is implemented through the following technical solution:

[0007] The present invention proposes a precision probe manipulator with adjustable motion direction stiffness, comprising:

[0008] A variable motion direction stiffness flexible micro-motion platform includes a platform body. A square hole stage is provided at the center of the platform body. Composite parallel guide flexible components are symmetrically arranged on the first opposite sides of the square hole stage. Each composite parallel guide flexible component is connected to the square hole stage through a curved beam. Guide beam flexible components are symmetrically arranged on the second opposite sides of the square hole stage. One guide beam flexible component is connected to the square hole stage through a first square rod, and the other guide beam flexible component is connected to the square hole stage through a second square rod. The end of the first square rod is connected to the output end of a bridge amplification flexible component. A piezoelectric ceramic actuator is provided inside the bridge amplification flexible component. A force sensor is installed inside the square hole stage. One end of the force sensor is connected to one side of the square hole stage, and the other end is connected to the tail end of a probe. The probe extends through the second square rod to the outside of the platform body.

[0009] The diamond-shaped clamping and adjusting mechanism has a voice coil motor driver placed at its center. On the first opposite side of its center, there is a voice coil motor mounting plate, which fixes the stator and mover of the voice coil motor respectively. On the second opposite side of its center, there is a mounting post. The adjacent voice coil motor mounting plates and mounting posts are connected by flexible leaf springs of equal size and thickness, and the bottom of the mounting posts is connected to a composite parallel guide flexible component.

[0010] As a further technical solution, the probe passes through the square rod and the body, extending out of the body.

[0011] As a further technical solution, the composite parallel guide flexible component includes a first moving block, a second moving block, and a third moving block; the third moving block and the second moving block are disposed on both sides of the first moving block, and the third moving block and the first moving block are connected by two first leaf springs, and the second moving block and the first moving block are also connected by two other second leaf springs; the second moving block is connected to the lower base plate by two second leaf springs, and the third moving block is also connected to the lower base plate by two other second leaf springs.

[0012] As a further technical solution, the mounting post of the rhombic clamping stiffness adjustment mechanism is connected to the first moving block. The mounting post of the rhombic clamping stiffness adjustment mechanism is provided with a threaded hole aligned with the mounting hole of the composite parallel guide flexible component, so as to ensure that the rhombic clamping stiffness adjustment mechanism can be installed on the variable motion stiffness flexible micro-motion platform.

[0013] As a further technical solution, the first moving block is connected to the square hole platform via a curved beam.

[0014] As a further technical solution, the bridge-type amplification flexible component is provided with a piezoelectric ceramic actuator pre-tightening threaded hole for installing the piezoelectric ceramic actuator.

[0015] As a further technical solution, a first through hole is provided inside the second square rod, and a first rubber ring is provided inside the first through hole, with the probe supported by the first rubber ring.

[0016] As a further technical solution, a second through hole is provided on the main body, and a second rubber ring is provided inside the second through hole, through which the probe is supported.

[0017] As a further technical solution, an upper cover plate is also included, which is located on the top of the variable motion stiffness flexible micro-motion platform and has a slot at the position of the diamond clamping stiffness adjustment mechanism.

[0018] As a further technical solution, a motor cover plate is also included, which is connected to the upper cover plate and covers the slot in the upper cover plate.

[0019] As a further technical solution, a bottom plate is also included, which is located at the bottom of the variable motion stiffness flexible micro-motion platform. Its maximum width does not affect the flexible component function of the variable motion stiffness flexible micro-motion platform.

[0020] The beneficial effects of the present invention are as follows:

[0021] This invention amplifies the displacement of the piezoelectric ceramic actuator through a bridge-type amplification mechanism, while a guide beam provides displacement constraint in that direction, thereby achieving controllable micro-motion. Simultaneously, the invention uses a voice coil motor to drive a rhomboid clamping and stiffening mechanism to clamp the curved beam perpendicular to the direction of motion, achieving adjustable negative stiffness in that direction. A composite guiding mechanism guides the rhomboid clamping and stiffening mechanism perpendicular to the direction of motion. A force sensor at the probe tip enables real-time sensing of the force applied to the probe. Attached Figure Description

[0022] The accompanying drawings, which form part of this invention, are used to provide a further understanding of the invention. The illustrative embodiments of the invention and their descriptions are used to explain the invention and do not constitute an improper limitation of the invention.

[0023] Figure 1 This is a schematic diagram of a precision probe manipulator with adjustable motion direction stiffness in an embodiment of the present invention.

[0024] Figure 2 This is an exploded view of the structure of a precision probe manipulator with adjustable motion direction stiffness in an embodiment of the present invention.

[0025] Figure 3 This is a main structural diagram of the precision probe manipulator with adjustable motion direction stiffness in an embodiment of the present invention.

[0026] Figure 4 , Figure 5 This is a structural diagram of the variable motion direction stiffness flexible micro-motion platform in an embodiment of the present invention.

[0027] Figure 6 , Figure 7 This is a schematic diagram of probe installation in an embodiment of the present invention.

[0028] Figure 8 , Figure 9 This is a schematic diagram of the diamond-shaped clamping and stiffening mechanism in an embodiment of the present invention.

[0029] Figure 10 This is a schematic diagram of the lower base plate structure in an embodiment of the present invention.

[0030] Figure 11 This is a schematic diagram of the upper cover plate structure in an embodiment of the present invention.

[0031] Figure 12 This is a schematic diagram of the motor cover structure in an embodiment of the present invention.

[0032] The diagram exaggerates the spacing or dimensions between parts to show their positions; the diagram is for illustrative purposes only.

[0033] Among them: 1. Variable motion direction stiffness flexible micro-motion platform, 2. Rhomboid clamping stiffness adjustment mechanism, 3. Lower base plate, 4. Upper cover plate, 5. Motor cover plate, 6. Fixing screw, 7. Probe, 8. Piezoelectric ceramic actuator, 9. Force sensor, 11. Rubber ring;

[0034] 10. Voice coil motor driver; 101. Composite parallel guide flexible assembly; 1011. First moving block; 1012. First leaf spring; 1013. Second moving block; 1014. Third moving block; 1015. Second leaf spring;

[0035] 102. Curved beam; 103. Square hole platform; 104. Bridge-type enlarged flexible component; 105. Rubber ring mounting hole; 106. Mounting column mounting hole; 107. Flexible guide beam assembly; 108. Square rod.

[0036] 201. Mounting post, 202. Leaf spring, 203. Voice coil motor mounting plate. Detailed Implementation

[0037] It should be noted that the following detailed description is illustrative and intended to provide further explanation of the invention. Unless otherwise specified, all technical and scientific terms used in this invention have the same meaning as commonly understood by one of ordinary skill in the art to which this invention pertains.

[0038] As described in the background section, existing precision probe manipulators cannot simultaneously provide stiffness adjustment while meeting high-precision operation tasks, and cannot simultaneously achieve simpler and faster precision force and displacement operations. This invention proposes a precision probe manipulator with adjustable stiffness in the motion direction. When a piezoelectric ceramic actuator with infinite resolution is used in conjunction with a frictionless, gapless flexible component to achieve high-precision probe actuation, the stiffness of the precision probe manipulator in the motion direction is adjusted through a diamond-shaped clamping stiffness adjustment mechanism.

[0039] This embodiment discloses a precision probe manipulator with adjustable motion direction stiffness, such as... Figure 1 As shown, Figure 2 Exploded view of a portion of the structure of a precision probe manipulator with adjustable motion direction stiffness;

[0040] The precision probe manipulator with adjustable motion direction stiffness disclosed in this embodiment includes a flexible micro-motion platform with variable motion direction stiffness 1, a diamond clamping stiffness adjustment mechanism 2, a lower base plate 3, an upper cover plate 4, a motor cover plate 5, a fixing screw 6, a probe 7, a piezoelectric ceramic actuator 8, a force sensor 9, and a voice coil motor actuator 10. Figure 3 This is a main structural diagram of a precision probe manipulator with adjustable stiffness in the direction of motion. The invention is a one-dimensional precision probe manipulator, characterized by adjustable stiffness in the direction of motion. This invention features a unique diamond-shaped clamping stiffness adjustment mechanism, which compresses the curved beam by squeezing it from both sides towards the center, thereby obtaining adjustable negative stiffness in the direction of motion. This negative stiffness is achieved by connecting it in parallel with a bridge-type amplification mechanism, a guide beam, and other positive stiffness mechanisms in the direction of motion, thus realizing stiffness adjustment in the direction of motion.

[0041] A variable motion direction stiffness flexible micro-motion platform 1 includes a platform body. A square hole platform 103 is provided at the center of the platform body. Composite parallel guide flexible components 101 are symmetrically arranged on the first opposite sides of the square hole platform 103. Each composite parallel guide flexible component 101 is connected to the square hole platform 103 through a curved beam. Flexible guide beam components 107 are symmetrically arranged on the second opposite sides of the square hole platform 103. One flexible guide beam component 107 is connected to the square hole platform 103 through a first square rod 108. The other flexible guide beam component 107 is connected to the square hole platform 103 through a second square rod 108. A bridge-type amplification flexible component 104 is provided at the end of the first square rod 108. A first through hole is provided in the second square rod 108, and a first rubber ring 11 is provided in the first through hole. The probe is supported by the first rubber ring. A second through hole is provided on the platform body, and a second rubber ring 11 is provided in the second through hole. The probe is supported by the second rubber ring.

[0042] Furthermore, the diamond-shaped clamping and adjusting mechanism 2 has a voice coil motor driver placed at its center; a voice coil motor mounting plate is provided on the first opposite side of its center, i.e., there are two voice coil motor mounting plates, which respectively fix the stator and mover of the voice coil motor; a mounting post is provided on the second opposite side of its center, i.e., there are two mounting posts; adjacent voice coil motor mounting plates and mounting posts are connected by flexible leaf springs of equal size and thickness, i.e., the two voice coil motor mounting plates and the two mounting posts are connected by four flexible leaf springs, forming the mounting space for the voice coil motor driver.

[0043] Furthermore, Figure 4 This is a structural diagram of a variable motion direction stiffness flexible micro-motion platform 1. The variable motion direction stiffness flexible micro-motion platform 1 includes a main body, on which are mounted a composite parallel guide flexible component 101, a curved beam 102, a square hole platform 103, a bridge-type amplification flexible component 104, a rubber ring mounting hole 105, and a mounting column mounting hole 106. Figure 5 This is a schematic diagram of probe installation.

[0044] Furthermore, the composite parallel guide flexible components 101 are symmetrically distributed on both sides of the square hole platform 4; each composite parallel guide flexible component 101 includes a third moving block 1014, a first moving block 1011, a second moving block 1013, and a first leaf spring 1012. The third moving block 1014 and the second moving block 1013 are disposed on both sides of the first moving block 1011, and the third moving block 1014 and the first moving block 1011 are connected by two first leaf springs 1012 (middle side). The second moving block 1013 and the first moving block 1011 are also connected by two other first leaf springs 1012 (middle side). The second moving block 1013 is connected to the lower base plate 3 by two second leaf springs 1015 (two outer ones), and the third moving block 1014 is also connected to the lower base plate 3 by two other second leaf springs 1015 (two outer ones).

[0045] Furthermore, the first moving block 1011 is provided with a mounting post mounting hole 106, which is used to install the diamond clamping and adjusting mechanism 2 and provides a guide perpendicular to the direction of movement to ensure that the diamond clamping and adjusting mechanism 2 can compress the curved beam 102 simultaneously when driven by the voice coil motor.

[0046] Furthermore, the curved beam 102 can generate negative stiffness in the direction of motion by being compressed, and is connected in parallel with the positive stiffness mechanism of the composite parallel guide flexible component 101.

[0047] Furthermore, the bridge-type amplification flexible component 104 can be equipped with a piezoelectric ceramic actuator for amplifying the displacement of the piezoelectric ceramic actuator.

[0048] Furthermore, the rubber ring mounting hole 105 is used to install the rubber ring 11.

[0049] Furthermore, the mounting hole 106 is reserved for the assembly of the mounting hole 201 of the diamond clamping and stiffening mechanism 2; the mounting hole 106 is located in the middle of the composite parallel guide flexible component 101.

[0050] Furthermore, such as Figure 6 , Figure 7 As shown, the end of probe 7 is connected to force sensor 9 and passes through the inner hole of rubber ring 11; force sensor 9 is installed inside square hole platform 103, with one end of force sensor 9 fixed to the inner wall of square hole platform 103 and the other end connected to the tail end of probe 7; there are two rubber rings 11 in this embodiment, one of which is installed on the body of variable motion direction stiffness flexible micro-motion platform 1, and the other is installed in rubber ring mounting hole 105 inside square rod 108, as shown in the figure. Figure 5-Figure 2 As shown.

[0051] Figure 8 , Figure 9 This is a schematic diagram of the diamond-shaped clamping and adjusting mechanism 2. The voice coil motor driver 10 is mounted on the voice coil motor mounting plate 203, ensuring that the voice coil motor driver 10 is at the center position of the diamond-shaped clamping and adjusting mechanism 2. When the voice coil motor extends, it causes the mounting post 201 to move towards the center position simultaneously, achieving symmetrical compression of the curved beam 102.

[0052] Furthermore, the structure of the lower base plate 3 is as follows: Figure 10 As shown, the bottom plate has slots for wiring.

[0053] Furthermore, the structure of the upper cover plate 4 is as follows: Figure 11 As shown, the upper cover plate 4 has a slot at the corresponding position of the diamond-shaped clamping and adjusting mechanism 2 for easy maintenance. Threaded holes are present around the perimeter for mounting the motor cover plate 5.

[0054] Furthermore, the structure of the motor cover 5 is as follows: Figure 12 As shown, the motor cover 5 is used for dust and impact protection of the diamond clamping and adjusting mechanism 2, and is fabricated from sheet metal.

[0055] The working principle of the device proposed in this invention is as follows:

[0056] This invention amplifies the displacement of the piezoelectric ceramic actuator 8 through a bridge-type amplification flexible component 104, and achieves micro-motion in a single degree of freedom by pushing a square hole stage 103 through a square rod 108. A force sensor 9 is installed inside the square hole stage 103, and the force sensor 9 is connected to a probe 7. The probe 7 is constrained by a rubber ring 11, which is installed in a rubber ring mounting hole 105. The micro-motion of the square hole stage 103 in a single degree of freedom drives the movement of the probe 7. A flexible guide beam assembly 107 provides displacement constraint for the square hole stage 103 in the direction of motion. A curved beam 102 is provided in the direction of motion perpendicular to the square hole stage 103. A voice coil motor driver 10 drives a rhomboid clamping stiffness adjustment mechanism 2 to clamp the curved beam 102 perpendicular to the direction of motion, achieving adjustable negative stiffness in the direction of motion. A composite parallel guide flexible component 101 guides the rhomboid clamping stiffness adjustment mechanism 2 in the direction perpendicular to the direction of motion.

[0057] The piezoelectric ceramic actuator 8 amplifies the output displacement in the bridge-type amplification flexible component 104. The flexible guide beam assembly 107 provides constraint in the non-motion direction. A square rod 108 pushes a square hole stage 103, which in turn drives the probe assembly (including force sensor 9 and probe 7) to accurately reach the preset position and maintain contact between the probe 7 tip and the specimen. The voice coil motor actuator 10 drives the diamond-shaped clamping stiffness adjustment mechanism 2 to clamp the curved beam 102 in the perpendicular and motion directions, allowing adjustment of the negative stiffness of the curved beam 102 in the motion direction. After precise positioning provided by the piezoelectric ceramic actuator 8, the adjustable negative stiffness of the curved beam 102 results in adjustable overall stiffness of the mechanism in the motion direction. With the position unchanged, stiffness is proportional to the magnitude of the force. Adjusting the compression of the curved beam 102 by the voice coil motor actuator 10 allows adjustment of the probe contact force at a specified position.

[0058] It should be noted that the position sensor required for probe 7 positioning can be provided with position feedback by an external high-precision laser sensor, and this patent does not limit this sensing method.

[0059] The adjustable negative stiffness of this invention is achieved entirely by a flexible mechanism. The driving force of the voice coil motor is the Lorentz force, which only provides energy and does not directly provide stiffness adjustment. This invention achieves adjustable negative stiffness through a diamond-shaped clamping adjustment mechanism.

[0060] This invention employs a bridge-type amplification mechanism, a guide beam, and piezoelectric ceramics to achieve precision motion. The invention includes a force sensor and a probe assembly, enabling precise positioning via the piezoelectric ceramics, bridge-type amplification mechanism, and guide beam. Stiffness is adjusted via a diamond-shaped clamping and stiffness-adjusting mechanism, thereby regulating the force applied to the probe. Changes in force are directly collected by the force sensor.

[0061] Finally, it should be noted that relational terms such as first and second are used only to distinguish one entity or operation from another, and do not necessarily require or imply any such actual relationship or order between these entities or operations.

[0062] The above description is merely a preferred embodiment of the present invention and is not intended to limit the invention. Various modifications and variations can be made to the present invention by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the scope of protection of the present invention.

Claims

1. A precision probe manipulator with adjustable motion direction stiffness, characterized in that, include: A variable motion direction stiffness flexible micro-motion platform includes a platform body. A square hole stage is provided at the center of the platform body. Composite parallel guide flexible components are symmetrically arranged on the first opposite sides of the square hole stage. Each composite parallel guide flexible component is connected to the square hole stage through a curved beam. Guide beam flexible components are symmetrically arranged on the second opposite sides of the square hole stage. One guide beam flexible component is connected to the square hole stage through a first square rod, and the other guide beam flexible component is connected to the square hole stage through a second square rod. The end of the first square rod is connected to the output end of a bridge amplification flexible component. A piezoelectric ceramic actuator is provided inside the bridge amplification flexible component. A force sensor is installed inside the square hole stage. One end of the force sensor is connected to one side of the square hole stage, and the other end is connected to the tail end of a probe. The probe extends through the second square rod to the outside of the platform body. The diamond-shaped clamping and adjusting mechanism has a voice coil motor driver placed at its center. On the first opposite side of its center, there is a voice coil motor mounting plate, which fixes the stator and mover of the voice coil motor respectively. On the second opposite side of its center, there is a mounting post. The adjacent voice coil motor mounting plates and mounting posts are connected by flexible leaf springs of equal size and thickness, and the bottom of the mounting posts is connected to a composite parallel guide flexible component.

2. The precision probe manipulator with adjustable motion direction stiffness as described in claim 1, characterized in that, The composite parallel guide flexible component includes a first moving block, a second moving block, and a third moving block; the third moving block and the second moving block are disposed on both sides of the first moving block, and the third moving block and the first moving block are connected by two first leaf springs, and the second moving block and the first moving block are also connected by two other second leaf springs; the second moving block is connected to the lower base plate by two second leaf springs, and the third moving block is also connected to the lower base plate by two other second leaf springs.

3. A precision probe manipulator with adjustable motion direction stiffness as described in claim 2, characterized in that, The mounting column of the diamond-shaped clamping and adjusting mechanism is connected to the first moving block.

4. A precision probe manipulator with adjustable motion direction stiffness as described in claim 2, characterized in that, The first moving block is connected to the square hole platform via a curved beam.

5. A precision probe manipulator with adjustable motion direction stiffness as described in claim 1, characterized in that, The bridge-type amplification flexible component is provided with a piezoelectric ceramic actuator pre-tightening threaded hole for mounting the piezoelectric ceramic actuator.

6. A precision probe manipulator with adjustable motion direction stiffness as described in claim 1, characterized in that, The second square rod has a first through hole, and a first rubber ring is placed inside the first through hole. The probe is supported by the first rubber ring.

7. A precision probe manipulator with adjustable motion direction stiffness as described in claim 6, characterized in that, A second through hole is provided on the main body, and a second rubber ring is provided inside the second through hole. The probe is supported by the second rubber ring.

8. A precision probe manipulator with adjustable motion direction stiffness as described in claim 1, characterized in that, It also includes an upper cover plate, which is located on top of the variable motion stiffness flexible micro-motion platform and has a slot at the location of the diamond clamping stiffness adjustment mechanism.

9. A precision probe manipulator with adjustable motion direction stiffness as described in claim 8, characterized in that, It also includes a motor cover plate, which is connected to the upper cover plate and covers the slotted upper cover plate.

10. A precision probe manipulator with adjustable motion direction stiffness as described in claim 1, characterized in that, It also includes a bottom plate, which is located at the bottom of the variable motion stiffness flexible micro-motion platform. Its maximum width does not affect the flexible component function of the variable motion stiffness flexible micro-motion platform.

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