CN111384873A - A bionic inchworm drive device and excitation method thereof - Google Patents

Abstract

The invention belongs to the field of precision driving, and in particular relates to a bionic inchworm type 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 driving unit, a clamping unit, a rotor, a screw and a base; the driving unit and the clamping unit are installed on the base by screws; the device adopts the excitation method of voltage signal timing control, so that the driving unit and the clamping unit work alternately and cooperatively , can realize large-stroke high-precision rotary motion, and can be used in precision ultra-precision machining, micro-electromechanical systems, micro-manipulation robots, biotechnology, aerospace and other fields.

Description

A bionic inchworm drive device and excitation method thereof

technical field

The invention relates to a micro-nano precision driving device, in particular to a bionic inchworm type 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 machining and measurement, optical engineering, intelligent robots, modern medical care, and aerospace technology. In order to achieve micro/nano-level output precision, the application of modern precision drive technology puts forward higher requirements for the precision of the drive device. The traditional driving device has low output precision and large overall size, which cannot meet the requirements of micro/nano-level high precision and small size of the driving device in the precision system of modern advanced technology. Piezoelectric drives 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 ensure high output precision and bearing capacity while obtaining a large output stroke, which has attracted extensive attention of researchers. The inchworm type driving device usually needs to use two clamping units, one driving unit, and multi-channel control, which has the problems of complex structure and difficult control, which is not conducive to the practical application of the inchworm type piezoelectric drive. Therefore, it is necessary to design an inchworm piezoelectric driving device that can simplify the structure and control.

SUMMARY OF THE INVENTION

The purpose of the present invention is to provide a bionic inchworm type driving device and an excitation method thereof to solve the above problems existing in the prior art. Through the time sequence control of the voltage signal, the present invention uses a group of driving units and a group of clamping units to work alternately and cooperatively, so as to realize the large-stroke and high-precision rotary drive, and at the same time, the device structure and control can be effectively simplified.

The above-mentioned purpose of the present invention is achieved through the following technical solutions:

A bionic inchworm type driving device, comprising a driving unit, a clamping unit, a rotor, a screw and a base, the driving unit and the clamping unit are mounted on the base by screws; The units work together alternately to drive the rotor to rotate.

The drive unit includes a piezoelectric stack, a flexible hinge mechanism, and a pre-tightening wedge; the piezoelectric stack is obliquely placed in the flexible hinge mechanism, and pre-tightened by the pre-tightening wedge; the flexible hinge mechanism includes four thin-walled flexible For the hinge, the initial pre-tightening force between the flexible hinge mechanism and the rotor can be adjusted through the screw, the arc-shaped convex part is in contact with the rotor, and the electric extension of the piezoelectric stack can push the arc-shaped convex part to tighten the rotor and drive the rotor to rotate.

The clamping unit includes a piezoelectric stack, a flexible hinge mechanism, and a pre-tightening wedge; the piezoelectric stack is installed in the flexible hinge mechanism, and is pre-tightened by the pre-tightening wedge; the flexible hinge mechanism includes four thin-walled flexible For the hinge, the initial pre-tightening force between the flexible hinge mechanism and the rotor can be adjusted through the screw, the arc-shaped convex part is in contact with the rotor, and the electric extension of the piezoelectric stack can push the arc-shaped convex part against the rotor to achieve clamping.

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

Step ①, initial state: adjust the screw to control the initial preload between the flexible hinge mechanism and the rotor; use two sets of voltage signals to control the driving unit and the clamping unit respectively; the piezoelectric stacks of the driving unit and the clamping unit are not charged;

Step ②, the drive unit pushes the rotor to rotate;

Step ③, the clamping unit clamps the rotor;

The fourth step, the drive unit is restored to the initial state;

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

In step ⑥, the above steps are repeated, the driving unit and the clamping unit work alternately, and the driving device can realize large-stroke high-precision rotary motion.

The main advantage of the present invention is: through the time sequence control of the voltage signal, a group of driving units and a group of clamping units are used to work alternately and cooperatively, so that the micro-nano level large-stroke rotational motion can be realized, and the device structure and control can be effectively simplified. The device can be applied to important scientific and engineering fields such as precision ultra-precision machining, micro-manipulation robots, micro-electromechanical systems, large-scale integrated circuit manufacturing, and biotechnology.

Description of drawings

The accompanying drawings here are used to provide a further understanding of the present invention and constitute a part of the present application. The schematic 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.

1 is a schematic isometric view of the present invention;

Fig. 2 is the schematic diagram of the flexible hinge mechanism of the drive unit of the present invention;

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

FIG. 4 is a voltage signal applied to 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. Clamping 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 details of the present invention and the specific implementations thereof will be further described below with reference to the accompanying drawings.

Referring to Figures 1 to 3, a bionic inchworm driving device mainly includes a driving unit (1), a clamping unit (4), a rotor (2), a screw (5) and a base (3), and the driving unit ( 1) and the clamping unit (4) are mounted on the base (3) through screws (5); the device makes the driving unit (1) and the clamping unit (4) work alternately and cooperatively by controlling the voltage signal sequence to drive the rotor (2) Do a rotating motion.

The drive unit (1) includes a flexible hinge mechanism I(1-3), a preload wedge I(1-2), 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 pre-tightening wedge I (1-2); ) The initial preload force between the flexible hinge mechanism I (1-3) and the rotor (2) can be adjusted, the arc-shaped convex part is in contact with the rotor (2), and the piezoelectric stack I (1-1) is electrically stretched. The long can push the arc-shaped convex 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), a flexible hinge mechanism II (4-3); the piezoelectric stack II (4-2) 1) Installed in the flexible hinge mechanism II (4-3), and pre-tightened by the pre-tightening wedge II (4-2); the flexible hinge mechanism II (4-3) contains four thin-walled flexible hinges, which are 5) The initial preload force between the flexible hinge mechanism II (4-3) and the rotor (2) can be adjusted, the arc-shaped convex part is in contact with the rotor (2), and the piezoelectric stack II (4-1) is energized The elongation can push the arc-shaped convex part against the rotor (2) to realize clamping.

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

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

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

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

The fourth step, the drive unit (1) is restored to the initial state;

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

In step ⑥, the above steps are repeated, the driving unit (1) and the clamping unit (4) work alternately, and the driving device can realize large-stroke and high-precision rotary motion.

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 preload 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. Piezoelectric stack I (1-1) and piezoelectric stack II (4-1) are not charged;

The second step, U1 rises the signal, the driving unit ( ₁ ) acts: when the piezoelectric stack I (1-1) is energized, it stretches through the inverse piezoelectric effect to drive the flexible hinge mechanism I (1-3) to deform, Cause the arc-shaped protrusion of the flexible hinge mechanism I (1-3) to press against the rotor (2), and at the same time drive the rotor (2) to rotate;

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

Step 4, U1 drops the signal, 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, the rotor (2) remains in the position after turning an angle;

Step ⑤, U ₂ drops the signal, 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, A motion cycle ends;

By 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 rotational motion.

The invention relates to a bionic inchworm type driving device and an excitation method thereof. Through the time sequence control of the voltage signal, a group of driving units and a group of clamping units are used to alternately work together, which can realize large-stroke precision rotational driving, and has the advantages of low heat generation and low heat generation. , The drive is stable, reliable and efficient.

Claims (4)

1. a bionic inchworm type driving device is characterized in that: comprising a driving unit, a clamping unit, a rotor, a screw and a base, and the driving unit and the clamping unit are installed on the base by screws; The excitation method makes the driving unit and the clamping unit work alternately and cooperatively to realize the rotational movement. 2 . The bionic inchworm type driving device according to claim 1 , wherein the driving unit comprises a piezoelectric stack, a flexible hinge mechanism, and a pre-tightening wedge; the piezoelectric stack is placed obliquely in the flexible hinge mechanism. 3 . , pre-tightened by pre-tightening wedges; the flexible hinge mechanism includes 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 convex part is in contact with the rotor, and the piezoelectric stack The electric extension can push the arc-shaped convex part against the rotor and drive the rotor to rotate. 3 . The bionic inchworm drive device according to claim 1 , wherein the clamping unit comprises a piezoelectric stack, a flexible hinge mechanism, and a pre-tightening wedge; the piezoelectric stack is installed in the flexible hinge mechanism. 4 . , pre-tightened by pre-tightening wedges; the flexible hinge mechanism includes 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 convex part is in contact with the rotor, and the piezoelectric stack Electric extension can push the arc-shaped convex part against the rotor to achieve clamping. 4. a kind of excitation method of bionic inchworm type driving device as claimed in claim 1, is characterized in that: comprises the following steps: Step ①, initial state: adjust the screw to control the initial preload between the flexible hinge mechanism and the rotor; use two sets of voltage signals to control the driving unit and the clamping unit respectively; the piezoelectric stacks of the driving unit and the clamping unit are not charged; Step ②, the drive unit pushes the rotor to rotate; Step ③, the clamping unit clamps the rotor; The fourth step, the drive unit is restored to the initial state; Step ⑤, the clamping unit returns to the initial state, and one movement cycle ends; By repeating the above steps, the driving unit and the clamping unit work alternately, and the driving device can realize rotational motion.

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