CN111384873B - Bionic inchworm type driving device and excitation method thereof - Google Patents

Abstract

The invention belongs to the field of precision driving, and specifically relates to a bionic inchworm driving device and an excitation method thereof. The invention solves the technical problems of complex structure and difficult control of the inchworm-type piezoelectric driving device. The device includes a drive unit, a clamp unit, a rotor, screws and a base; the drive unit and the clamp unit are installed on the base through screws; the device uses an excitation method controlled by voltage signal timing to enable the drive unit and the clamp unit to work together alternately , can achieve large-stroke and high-precision rotational motion, and can be used in precision and ultra-precision machining, micro-electromechanical systems, micro-operation robots, biotechnology, aerospace and other fields.

Description

A bionic inchworm driving device and its excitation method

Technical field

The invention relates to a micro-nano precision driving device, and in particular to a bionic inchworm driving device and an excitation method thereof.

Background technique

Precision drive technology with micro/nano-level positioning accuracy is a key technology in high-end scientific and technological fields such as ultra-precision processing and measurement, optical engineering, intelligent robots, modern medical care, and aerospace technology. In order to achieve micro/nano-level output accuracy, the application of modern precision drive technology places higher requirements on the accuracy of the drive device. The traditional drive device has low output precision and large overall size, and cannot meet the requirements of precision systems in modern advanced technology for micro/nano-level high precision and small drive device size. Piezoelectric drive devices have the advantages of small size, high displacement resolution, large output load, and high energy conversion rate. They can achieve micro/nano-level output accuracy and have been increasingly used in micro-positioning and precision ultra-precision machining. middle. The inchworm piezoelectric drive device can obtain a large output stroke while ensuring high output accuracy and load-bearing capacity, which has attracted widespread attention from researchers. Inchworm-type driving devices usually require two-way clamping units, one-way driving unit, and multi-channel control. They have problems of complex structure and difficult control, which are not conducive to the practical application of inchworm-type piezoelectric driving. Therefore, it is necessary to design an inchworm-type piezoelectric driving device that can simplify the structure and control.

Contents of the invention

The purpose of the present invention is to provide a bionic inchworm driving device and its excitation method to solve the above problems existing in the prior art. Through the timing control of voltage signals, the present invention uses a set of driving units and a set of clamping units to alternately work together to achieve large-stroke and high-precision rotational driving, while effectively simplifying the device structure and control.

The above objects of the present invention are achieved through the following technical solutions:

A bionic inchworm driving device includes a driving unit, a clamping unit, a rotor, screws and a base. The driving unit and the clamping unit are installed on the base through screws; the device controls the driving unit and the clamping unit by controlling the timing of voltage signals. The units work together alternately to drive the rotor to rotate.

The driving unit includes a piezoelectric stack, a flexible hinge mechanism, and a preloading wedge; the piezoelectric stack is placed obliquely in the flexible hinge mechanism and is preloaded by the preloading wedge; the flexible hinge mechanism includes four thin-walled flexible Hinge, the initial pre-tightening force between the flexible hinge mechanism and the rotor can be adjusted through screws. The arc-shaped protruding part is in contact with the rotor. The electrical extension of the piezoelectric stack can push the arc-shaped protruding part to tighten the rotor and drive the rotor to rotate.

The clamping unit includes a piezoelectric stack, a flexible hinge mechanism, and a preloading wedge; the piezoelectric stack is installed in the flexible hinge mechanism and is preloaded by the preloading wedge; the flexible hinge mechanism includes four thin-walled flexible Hinge, the initial pre-tightening force between the flexible hinge mechanism and the rotor can be adjusted through screws. The arc-shaped protruding part contacts the rotor, and the electrical extension of the piezoelectric stack can push the arc-shaped protruding part against the rotor to achieve clamping.

An excitation method for a bionic inchworm drive device includes the following steps:

Step 1, initial state: adjust the screw to control the initial pre-tightening force between the flexible hinge mechanism and the rotor; use two sets of voltage signals to control the drive unit and clamp unit respectively; the piezoelectric stacks of the drive unit and clamp unit are not charged;

Step 2: The drive unit drives the rotor to rotate;

Step ③: The clamping unit clamps the rotor;

Step ④, the drive unit returns to its initial state;

Step ⑤, the clamping unit returns to the initial state, and a movement cycle ends;

Step ⑥, repeat the above steps, the driving unit and the clamping unit work alternately. The driving device can realize large-stroke and high-precision rotation motion.

The main advantage of the present invention is that through the timing control of voltage signals, a set of driving units and a set of clamping units are used to alternately work together to achieve micro-nano-level large-stroke rotation, and at the same time, the device structure and control can be effectively simplified. The device can be used in important scientific and engineering fields such as precision ultra-precision machining, micro-operation robots, micro-electromechanical systems, large-scale integrated circuit manufacturing, and biotechnology.

Description of drawings

The description of the drawings here is used to provide a further understanding of the present invention and constitutes a part of the present application. The illustrative examples of the present invention and their descriptions are used to explain the present invention and do not constitute an improper limitation of the present invention.

Figure 1 is an isometric view of the present invention;

Figure 2 is a schematic diagram of the flexible hinge mechanism of the drive unit of the present invention;

Figure 3 is a schematic diagram of the flexible hinge mechanism of the clamping unit of the present invention;

Figure 4 is the voltage signal loaded on the piezoelectric stack of the driving unit and the piezoelectric stack of the clamping unit.

In the picture:

1. Drive unit; 2. Rotor; 3. Base;

4. Clamp unit; 5. Screw; 1-1. Piezoelectric stack I;

1-2. Preload wedge I; 1-3. Flexible hinge mechanism I; 4-1. Piezoelectric stack II;

4-2. Preload wedge II; 4-3. Flexible hinge mechanism II.

Detailed ways

The detailed content and specific implementation methods of the present invention will be further described below with reference to the accompanying drawings.

Referring to Figures 1 to 3, a bionic inchworm type driving device mainly includes a driving unit (1), a clamping unit (4), a rotor (2), a screw (5) and a base (3). The driving unit ( 1) and the clamping unit (4) are installed on the base (3) through screws (5); the device controls the voltage signal timing to make the driving unit (1) and the clamping unit (4) work together alternately to drive the rotor. (2) Make rotational movements.

The driving unit (1) includes a flexible hinge mechanism I (1-3), a preload wedge I (1-2), and a piezoelectric stack I (1-1); the piezoelectric stack I (1-1 ) is installed in the flexible hinge mechanism I (1-3) and is pre-tightened by the preload wedge I (1-2); the flexible hinge mechanism I (1-3) contains four thin-walled flexible hinges, which are pre-tensioned by the screws (5 ) The initial preload force between the flexible hinge mechanism I (1-3) and the rotor (2) can be adjusted. The arc-shaped protruding part contacts the rotor (2), and the piezoelectric stack I (1-1) is electrically stretched. The long one can push the arc-shaped protruding part to press against the rotor (2) and drive the rotor (2) to rotate.

The clamping unit (4) includes a piezoelectric stack II (4-1), a preload wedge II (4-2), and a flexible hinge mechanism II (4-3); the piezoelectric stack II (4- 1) Installed in the flexible hinge mechanism II (4-3), preloaded by the preload wedge II (4-2); the flexible hinge mechanism II (4-3) contains four thin-walled flexible hinges, which are preloaded by screws ( 5) The initial preload force between the flexible hinge mechanism II (4-3) and the rotor (2) can be adjusted. The arc-shaped protruding part contacts the rotor (2), and the piezoelectric stack II (4-1) is energized. Extending can push the arc-shaped convex part against the rotor (2) to achieve clamping.

An excitation method for a bionic inchworm drive device includes the following steps:

Step ①, initial state: adjust the screw (5) to control the initial pre-tightening force between the flexible hinge mechanism I (1-3), the flexible hinge mechanism II (4-3) and the rotor (2); use two sets of voltage signals Control the driving unit (1) and the clamping unit (4) respectively; the piezoelectric stacks of the driving unit (1) and the clamping unit (4) are not electrified;

Step ②, the drive unit (1) pushes the rotor (2) to rotate;

Step ③: The clamping unit (4) clamps the rotor (2);

Step ④, the drive unit (1) returns to the initial state;

Step ⑤, the clamping unit (4) returns to the initial state, and one movement cycle ends;

Step ⑥: Repeat the above steps, and the driving unit (1) and the clamping unit (4) work alternately. The driving device can realize large-stroke and high-precision rotation motion.

Referring to Figures 1 to 4, the specific working process of the present invention is as follows:

Step ①, initial state: adjust the screw (5) to control the initial pre-tightening force between the flexible hinge mechanism I (1-3), the flexible hinge mechanism II (4-3) and the rotor (2). Two sets of voltage signals U ₁ and U ₂ are used to control the piezoelectric stack I (1-1) in the driving unit (1) and the piezoelectric stack II (4-1) in the clamping unit (4) respectively. Neither the piezoelectric stack I(1-1) nor the piezoelectric stack II(4-1) is charged;

Step ②, U ₁ rises signal, the driving unit (1) acts: when the piezoelectric stack I (1-1) is energized, it stretches through the reverse piezoelectric effect, driving the flexible hinge mechanism I (1-3) to deform. As a result, the arc-shaped protrusion of the flexible hinge mechanism I (1-3) presses against the rotor (2), and at the same time drives the rotor (2) to rotate;

Step ③, U ₂ rising signal, clamping unit (4) action: before the piezoelectric stack I (1-1) loses power and retreats, the piezoelectric stack II (4-1) of the clamping unit (4) ) is energized and stretches through the inverse piezoelectric effect, pushing the arc-shaped protrusion of the flexible hinge mechanism II (4-3) against the rotor (2) for clamping;

Step ④, U ₁ drops the signal, and the drive unit (1) recovers: the piezoelectric stack I (1-1) loses power and returns to the initial state, the flexible hinge mechanism I (1-3) also returns to the initial state, and the rotor (2) Still maintaining the position after turning an angle;

Step ⑤, U ₂ decreases the signal and the clamping unit (4) recovers: the piezoelectric stack II (4-1) loses power and returns to the initial state, and the flexible hinge mechanism II (4-3) also returns to the initial state. The end of a movement cycle;

Repeating the above steps, the driving unit (1) and the clamping unit (4) work alternately, and the driving device can realize large-stroke and high-precision rotation motion.

The invention relates to a bionic inchworm driving device and an excitation method thereof. Through timing control of voltage signals, a group of driving units and a group of clamping units are used to alternately work together to achieve large-stroke precision rotational driving with low heat generation. , The driving characteristics are smooth, reliable and efficient.

Claims (2)

1. A bionic inchworm driving device, characterized in that: it includes a set of driving units, a set of clamping units, a rotor, screws and a base. The driving unit and the clamping unit are installed on the base through screws. The driving unit and The clamping units are relatively arranged on both sides of the rotor; the device adopts an excitation method controlled by voltage signal timing, so that the driving unit and the clamping unit alternately work together to achieve rotational motion; the driving unit includes a piezoelectric stack , flexible hinge mechanism, preloading wedge, the piezoelectric stack is placed obliquely in the flexible hinge mechanism, and is preloaded by the preloading wedge. The flexible hinge mechanism is square and contains four thin-walled flexible hinges, and the flexibility can be adjusted through screws The initial pre-tightening force between the hinge mechanism and the rotor, the arc-shaped protruding part contacts the rotor, and the piezoelectric stack is electrically extended to push the arc-shaped protruding part to tighten the rotor and drive the rotor to rotate; the clamping unit includes Piezoelectric stack, flexible hinge mechanism, and preloading wedge. The piezoelectric stack is installed in the flexible hinge mechanism and is preloaded by the preloading wedge. The flexible hinge mechanism is in a straight-shaped shape and contains four thin-walled flexible hinges. , the initial pre-tightening force between the flexible hinge mechanism and the rotor can be adjusted by screws, the arc-shaped protruding part contacts the rotor, and the electrical extension of the piezoelectric stack can push the arc-shaped protruding part against the rotor to achieve clamping. 2. An excitation method for the bionic inchworm drive device as claimed in claim 1, characterized in that it includes the following steps: Step 1, initial state: adjust the screw to control the initial pre-tightening force between the flexible hinge mechanism and the rotor; use two sets of voltage signals to control the drive unit and clamp unit respectively; the piezoelectric stacks of the drive unit and clamp unit are not charged; Step 2: The drive unit drives the rotor to rotate; Step ③: The clamping unit clamps the rotor; Step ④, the drive unit returns to its initial state; Step ⑤, the clamping unit returns to the initial state, and a movement cycle ends; Repeat the above steps, the driving unit and the clamping unit work alternately, and the driving device can realize rotational movement.