CN109861580B

CN109861580B - Six-degree-of-freedom piezoelectric motion platform and excitation method thereof

Info

Publication number: CN109861580B
Application number: CN201910280548.9A
Authority: CN
Inventors: 刘英想; 于洪鹏; 陈维山; 苏琪
Original assignee: Harbin Institute of Technology
Current assignee: Harbin Haoxing Technology Co ltd
Priority date: 2019-04-09
Filing date: 2019-04-09
Publication date: 2020-01-07
Anticipated expiration: 2039-04-09
Also published as: CN109861580A

Abstract

The invention discloses an ultra-precise six-degree-of-freedom piezoelectric motion platform and an excitation method thereof, and belongs to the technical field of piezoelectric drive. The upper side drive foot, the crooked type piezoelectric actuator of the two-way range upon range of formula of upside, the insulating layer, range upon range of formula torsional mode piezoelectric actuator, the direction splint, range upon range of formula linear type piezoelectric actuator and middle drive foot connect gradually from top to bottom, drive foot in the middle of vertical support column's top support, vertical support column, support splint, the crooked type piezoelectric actuator of the two-way range upon range of formula of downside and downside drive foot connect gradually from top to bottom, the active cell compresses tightly on the top surface of upper side drive foot, the lower extreme of downside drive foot compresses tightly on the upper surface of base, support splint and longitudinal rail sliding connection, longitudinal rail and transverse rail sliding connection and cross arrangement, transverse rail and pedestal connection. The invention has simple structure and reliable excitation method, can obtain large-scale and high-precision multi-degree-of-freedom motion, has wide application prospect in the fields of cell operation, microsurgery, optical adjustment, ultra-precision machining and the like, and can also generate certain promotion effect on the development of the precision piezoelectric driving technology.

Description

Six-degree-of-freedom piezoelectric motion platform and excitation method thereof

Technical Field

The invention belongs to the technical field of piezoelectric drive, and particularly relates to an ultra-precise six-degree-of-freedom piezoelectric motion platform and an excitation method thereof.

Background

Under the stimulation of the rapid development and huge demand in the fields of micro-nano operation and detection, microscopic life science, ultra-precision machining and the like, ultra-precision instruments and equipment are paid more and more attention and researched increasingly, and as a core element of the ultra-precision instruments and equipment, an ultra-precision driver is undoubtedly the most important part for research. In the field of ultra-precise instruments and equipment, the traditional electromagnetic driving principle is not applicable any more due to the severe application requirements of ultra-high precision, large stroke, compact structure size and certain load capacity. In contrast, the piezoelectric driving technology newly developed in recent years has the main advantages of high resolution, high response speed, good electromagnetic compatibility and compact and flexible structural design, and the combination of large stroke and high precision can be realized by using the stepping driving principle through simple structural design, so that the piezoelectric driving technology becomes an important driving element in ultra-precise instruments. Generally, the piezoelectric driving principle is to convert input electrical energy into output mechanical energy by using the inverse piezoelectric effect of a piezoelectric material, and the output mechanical energy can be accurately adjusted by regulating the magnitude of the input electrical quantity, so that high positioning accuracy can be obtained. Based on the existing mature ultra-precise piezoelectric driver, a direct driving mode and a stepping driving mode are applied generally, the existing mature ultra-precise multi-degree-of-freedom piezoelectric motion platform mostly adopts the direct driving mode, the driving mode has a simple structure, high load capacity and high resolution, but the stroke of the driving mode is severely limited, and can only reach millimeter level to the maximum extent, so that the application range of the driving mode is greatly limited; the motion stroke of the stepping type driving mode is theoretically infinite, and the requirement of ultra-precise motion can be met as long as a small motion step distance can be realized, so that the stepping type driving mode is an important direction for developing large-stroke ultra-precise motion elements. However, because multiple actuators are often required to be connected in series for multi-degree-of-freedom stepping drive, the defects of complex structure and large size are brought, so that the ultraprecise multi-degree-of-freedom piezoelectric motion platform which is simple and compact in structure and reliable and easy to excite has very important practical significance.

Disclosure of Invention

The invention aims to solve the technical problems of serious insufficient stroke, complex structure and huge size of the existing ultra-precise multi-degree-of-freedom piezoelectric motion platform, and provides an ultra-precise six-degree-of-freedom piezoelectric motion platform and an excitation method thereof.

The purpose of the invention is realized by the following technical scheme: an ultra-precise six-degree-of-freedom piezoelectric motion platform comprises a rotor, a four-degree-of-freedom driving unit, a vertical supporting column, a vertical guide rail, a transverse guide rail, a longitudinal guide rail, a two-degree-of-freedom driving unit and a base; the four-degree-of-freedom driving unit comprises an upper side driving foot, an upper side bidirectional stacked bending piezoelectric driver, an insulating layer, a stacked torsion piezoelectric driver, a guide clamping plate, a stacked linear piezoelectric driver and a middle driving foot; the two-degree-of-freedom driving unit comprises a supporting clamping plate, a lower-side bidirectional stacked bending piezoelectric driver and a lower-side driving foot; the upper side driving foot, the upper side bidirectional stacked bending piezoelectric driver, the insulating layer, the stacked torsion type piezoelectric driver, the guide clamping plate, the stacked linear piezoelectric driver and the middle driving foot are sequentially connected from top to bottom, and the top end of the vertical supporting column supports the middle driving foot; the vertical supporting column, the supporting clamping plate, the lower-side bidirectional stacked bending piezoelectric driver and the lower-side driving foot are sequentially connected from top to bottom; the rotor is tightly pressed on the top surface of the upper side driving foot, the middle driving foot is tightly pressed on the side surface of the vertical supporting column, and the lower end of the lower side driving foot is tightly pressed on the upper surface of the base; the vertical guide rails are arranged along the vertical direction, and the transverse guide rails and the longitudinal guide rails are respectively arranged along the horizontal direction and the depth direction; the supporting clamp plate is fixedly connected with the vertical guide rail, the guide clamp plate is slidably connected with the vertical guide rail, the supporting clamp plate is slidably connected with the longitudinal guide rail, the longitudinal guide rail is slidably connected with the transverse guide rail and is arranged in a crossed manner, and the transverse guide rail is fixedly connected with the base; the base is fixed, and the rotor outputs spatial six-degree-of-freedom motion.

Furthermore, the four-degree-of-freedom driving unit and the two-degree-of-freedom driving unit are used as energy conversion elements to realize conversion from input electric energy to output mechanical energy.

Furthermore, the upper side driving foot is provided with a positioning hole, the positioning hole is matched with the rotor, and the rotor is tightly pressed on the top surface of the upper side driving foot through the positioning hole; the middle driving foot is provided with a fixing hole, the fixing hole is matched with the vertical supporting column, and the middle driving foot is tightly pressed on the side face of the vertical supporting column through the fixing hole.

Furthermore, the upper-side bidirectional stacked bending piezoelectric actuator and the lower-side bidirectional stacked bending piezoelectric actuator are respectively formed by fixedly connecting a plurality of piezoelectric ceramic plates along the axial direction of the four-degree-of-freedom driving unit and the two-degree-of-freedom driving unit, and each piezoelectric ceramic plate comprises four polarization subareas. One pair of the bending sections is a horizontal bending section, and the other pair of the bending sections is a depth bending section; the bending deformation of the upper bidirectional stacked bending piezoelectric actuator and the lower bidirectional stacked bending piezoelectric actuator under an excitation signal respectively drives the upper driving foot and the lower driving foot to do reciprocating swing motion along the horizontal direction and the depth direction.

Furthermore, the laminated linear piezoelectric actuator is formed by fixedly connecting a plurality of layers of piezoelectric ceramic plates along the axial direction of the four-degree-of-freedom driving unit, and each piezoelectric ceramic plate only has one polarization partition; the telescopic deformation of the laminated linear piezoelectric actuator under the excitation signal drives the middle driving foot to do reciprocating linear motion along the vertical direction.

Furthermore, the stacked torsional piezoelectric actuator is formed by fixedly connecting a plurality of piezoelectric ceramic plates around the axis direction of the four-degree-of-freedom driving unit, and each piezoelectric ceramic plate only has one polarization partition; torsional deformation of the laminated torsional piezoelectric driver under an excitation signal drives the upper side driving foot to do reciprocating rotary motion around the vertical direction.

Furthermore, the number of the two-degree-of-freedom driving units is one or more, and the multiplication of the load capacity can be realized by increasing the number of the two-degree-of-freedom driving units.

An excitation method of an ultra-precise six-degree-of-freedom piezoelectric motion platform is applied to the ultra-precise six-degree-of-freedom piezoelectric motion platform

The axis direction of the four-degree-of-freedom driving unit is a Z axis, and the clockwise direction of the Z axis is a positive direction;

the depth direction orthogonal to the axial direction of the four-degree-of-freedom driving unit is an X axis, and the clockwise direction of the X axis is a positive direction;

the horizontal direction orthogonal to the axial direction of the four-degree-of-freedom drive unit is a Y axis, the clockwise direction of the Y axis is a positive direction,

the method is characterized in that:

when the mover makes a straight line motion along the positive direction of the Y axis, the method comprises the following steps:

s100, pressing the rotor on the top surface of the upper side driving foot, adjusting the pre-pressure between the upper side driving foot and the upper side driving foot, pressing the middle side driving foot on the side surface of the vertical supporting column, adjusting the pre-pressure between the upper side driving foot and the lower side driving foot, pressing the lower side driving foot on the upper surface of the base, and adjusting the pre-pressure between the upper side driving foot and the lower side driving foot;

s110, applying an excitation voltage signal with a slowly rising amplitude to a Y-axis direction bending partition in the lower bidirectional stacked bending piezoelectric driver, wherein the lower bidirectional stacked bending piezoelectric driver is bent and deformed to drive the lower driving foot to slowly swing to a limit position along a Y-axis reverse direction, and under the action of static friction force between the lower driving foot and the base, the two-degree-of-freedom driving unit and the four-degree-of-freedom driving unit generate linear displacement along the Y-axis positive direction, so that the mover is driven to generate linear displacement output along the Y-axis positive direction;

s120, applying an excitation voltage signal with a rapidly reduced amplitude to a Y-axis direction bending partition in the lower bidirectional stacked bending piezoelectric driver, enabling the lower bidirectional stacked bending piezoelectric driver to bend and deform to drive the lower driving foot to rapidly swing to an initial position along the positive direction of a Y axis, and under the action of inertia of the two-degree-of-freedom driving unit and the four-degree-of-freedom driving unit, enabling the lower driving foot and the base to relatively slide and keep still, so that the rotor also keeps still;

s130, judging whether the mover moves by a specified displacement, if so, executing a step S140; otherwise, returning to step S110;

s140 stops moving the mover,

when the rotor linearly moves along the Y axis in the opposite direction, the method comprises the following steps:

s150, pressing the rotor on the top surface of the upper side driving foot, adjusting the pre-pressure between the upper side driving foot and the upper side driving foot, pressing the middle side driving foot on the side surface of the vertical supporting column, adjusting the pre-pressure between the upper side driving foot and the lower side driving foot, pressing the lower side driving foot on the upper surface of the base and adjusting the pre-pressure between the upper side driving foot and the lower side driving foot;

s160, applying an excitation voltage signal with a slowly-decreasing amplitude to a Y-axis direction bending partition in the lower bidirectional stacked bending piezoelectric driver, wherein the lower bidirectional stacked bending piezoelectric driver is bent and deformed to drive the lower driving foot to slowly swing to a limit position along the positive direction of the Y axis, and under the action of static friction force between the lower driving foot and the base, the two-degree-of-freedom driving unit and the four-degree-of-freedom driving unit generate linear displacement along the negative direction of the Y axis, so that the rotor is driven to generate linear displacement output along the negative direction of the Y axis;

s170, applying an excitation voltage signal with a rapidly rising amplitude to a Y-axis direction bending partition in the lower bidirectional stacked bending type piezoelectric driver, wherein the lower bidirectional stacked bending type piezoelectric driver is bent and deformed to drive the lower driving foot to rapidly swing to an initial position along the Y-axis direction, and under the action of inertia of the two-degree-of-freedom driving unit and the four-degree-of-freedom driving unit, the lower driving foot and the base slide relatively to keep still, so that the rotor also keeps still;

s180, judging whether the mover moves by a specified displacement, and if so, executing a step S190; otherwise, returning to step S160;

s190 stops moving the mover,

when the rotor does positive direction linear motion along the X axis, the method comprises the following steps:

s200, pressing the rotor above the upper driving foot, adjusting the pre-pressure between the upper driving foot and the upper driving foot, pressing the middle driving foot on the side surface of the vertical supporting column, adjusting the pre-pressure between the upper driving foot and the lower driving foot, pressing the lower driving foot above the base, and adjusting the pre-pressure between the upper driving foot and the lower driving foot;

s210, applying an excitation voltage signal with a slowly rising amplitude value to an X-axis direction bending partition in the lower bidirectional stacked bending piezoelectric driver, driving the lower driving foot to slowly swing to a limit position along an X-axis direction by bending deformation of the lower bidirectional stacked bending piezoelectric driver, and generating linear displacement along the X-axis positive direction by the two-degree-of-freedom driving unit and the four-degree-of-freedom driving unit under the action of static friction force between the lower driving foot and the base, so as to drive the rotor to generate linear displacement output along the X-axis positive direction;

s220, applying an excitation voltage signal with a rapidly reduced amplitude to an X-axis direction bending partition in the lower bidirectional stacked bending type piezoelectric driver, driving the lower driving foot to rapidly swing to an initial position along the positive direction of an X axis by bending deformation of the lower bidirectional stacked bending type piezoelectric driver, and keeping the lower driving foot and the base stationary due to relative sliding under the action of inertia of the two-degree-of-freedom driving unit and the four-degree-of-freedom driving unit, so that the rotor also keeps stationary;

s230, judging whether the mover moves by a specified displacement, if so, executing a step S240; otherwise, returning to step S210;

s240 stops moving the mover,

when the rotor linearly moves along the X axis in the opposite direction, the method comprises the following steps:

s250, the rotor is tightly pressed above the upper side driving foot, the pre-pressure between the upper side driving foot and the upper side driving foot is adjusted, the middle driving foot is tightly pressed on the side face of the vertical supporting column, the pre-pressure between the upper side driving foot and the lower side driving foot is adjusted, and the pre-pressure between the lower side driving foot and the lower side driving foot is tightly pressed above the base;

s260, applying an excitation voltage signal with a slowly-decreasing amplitude to an X-axis direction bending partition in the lower bidirectional stacked bending piezoelectric driver, driving the lower driving foot to slowly swing to a limit position along the positive direction of the X-axis by bending deformation of the lower bidirectional stacked bending piezoelectric driver, and generating linear displacement along the negative direction of the X-axis by the two-degree-of-freedom driving unit and the four-degree-of-freedom driving unit under the action of static friction force between the lower driving foot and the base, so as to drive the rotor to generate linear displacement output along the negative direction of the X-axis;

s270, applying an excitation voltage signal with a rapidly rising amplitude to an X-axis direction bending partition in the lower bidirectional stacked bending piezoelectric driver, enabling the lower bidirectional stacked bending piezoelectric driver to bend and deform to drive the lower driving foot to rapidly swing to an initial position along the X-axis direction, and enabling the lower driving foot and the base to relatively slide and keep still under the action of inertia of the two-degree-of-freedom driving unit and the four-degree-of-freedom driving unit, so that the rotor also keeps still;

s280, judging whether the mover moves by the specified displacement, if so, executing the step S290; otherwise, returning to step S260;

s290 stops moving the mover,

when the rotor does straight-line motion along the Z axis, the method comprises the following steps:

s300, pressing the rotor above the upper driving foot, adjusting the pre-pressure between the upper driving foot and the upper driving foot, pressing the middle driving foot on the side surface of the vertical supporting column, adjusting the pre-pressure between the upper driving foot and the lower driving foot, pressing the lower driving foot above the base, and adjusting the pre-pressure between the upper driving foot and the lower driving foot;

s310, applying an excitation voltage signal with a slowly rising amplitude to the stacked linear piezoelectric actuator, wherein the stacked linear piezoelectric actuator is deformed in a stretching way to drive the middle driving foot to slowly move to a limit position along the Z-axis reverse direction, and under the action of static friction between the middle driving foot and the vertical supporting column, the four-degree-of-freedom driving unit generates linear displacement along the Z-axis positive direction, so as to drive the rotor to generate linear displacement output along the Z-axis positive direction;

s320, applying an excitation voltage signal with a rapidly-reduced amplitude to the stacked linear piezoelectric actuator, wherein the stacked linear piezoelectric actuator is deformed in a stretching way to drive the middle driving foot to rapidly move to a limit position along the positive direction of the Z axis, and under the action of inertia of the four-degree-of-freedom driving unit, the middle driving foot and the vertical supporting column slide relatively to keep still, so that the rotor also keeps still;

s330, judging whether the mover moves by a specified displacement, if so, executing a step S340; otherwise, returning to step S310;

s340 stops moving the mover,

when the rotor linearly moves along the Z axis in the opposite direction, the method comprises the following steps:

s350, the rotor is tightly pressed above the upper side driving foot, the pre-pressure between the upper side driving foot and the upper side driving foot is adjusted, the middle driving foot is tightly pressed on the side face of the vertical supporting column, the pre-pressure between the upper side driving foot and the lower side driving foot is adjusted, and the pre-pressure between the lower side driving foot and the lower side driving foot is tightly pressed above the base;

s360, applying an excitation voltage signal with a slowly-reduced amplitude to the stacked linear piezoelectric actuator, wherein the stacked linear piezoelectric actuator is deformed in a stretching manner to drive the middle driving foot to slowly move to a limit position along the positive direction of the Z axis, and under the action of static friction between the middle driving foot and the vertical supporting column, the four-degree-of-freedom driving unit generates linear displacement along the negative direction of the Z axis, so that the rotor is driven to generate linear displacement output along the negative direction of the Z axis;

s370, applying an excitation voltage signal with a rapidly rising amplitude to the stacked linear piezoelectric actuator, wherein the stacked linear piezoelectric actuator is deformed in a stretching manner to drive the middle driving foot to rapidly move to an extreme position along the Z-axis in a reverse direction, and under the action of inertia of the four-degree-of-freedom driving unit, the middle driving foot and the vertical supporting column slide relatively to keep still, so that the rotor also keeps still;

s380, judging whether the mover moves by a specified displacement, if so, executing a step S390; otherwise, returning to step S360;

s390 stops moving the mover,

when the rotor rotates around the Y axis in the positive direction, the method comprises the following steps:

s400, pressing the rotor above the upper driving foot, adjusting the pre-pressure between the upper driving foot and the upper driving foot, pressing the middle driving foot on the side surface of the vertical supporting column, adjusting the pre-pressure between the upper driving foot and the lower driving foot, pressing the lower driving foot above the base, and adjusting the pre-pressure between the upper driving foot and the lower driving foot;

s410, applying slowly rising excitation voltage signals to X-axis direction bending partitions in the upper bidirectional stacked bending piezoelectric driver, driving the upper driving foot to slowly swing to a limit position along an X-axis direction by bending deformation of the upper bidirectional stacked bending piezoelectric driver, and generating rotary displacement output by the rotor around a Y-axis positive direction under the action of static friction force between the upper driving foot and the rotor;

s420, applying an excitation voltage signal with a rapidly reduced amplitude to an X-axis direction bending partition in the upper bidirectional stacked bending type piezoelectric driver, enabling the upper bidirectional stacked bending type piezoelectric driver to bend and deform to drive the upper driving foot to rapidly swing to an initial position along the positive direction of an X axis, and enabling the rotor and the upper driving foot to relatively slide and keep still under the action of inertia of the rotor;

s430, judging whether the rotor rotates by a specified displacement, if so, executing a step S440; otherwise, returning to step S410;

s440 stops rotating the mover,

when the rotor rotates around the Y axis in the opposite direction, the method comprises the following steps:

s450, the rotor is tightly pressed above the upper side driving foot, the pre-pressure between the upper side driving foot and the upper side driving foot is adjusted, the middle driving foot is tightly pressed on the side face of the vertical supporting column, the pre-pressure between the upper side driving foot and the lower side driving foot is adjusted, and the pre-pressure between the lower side driving foot and the lower side driving foot is tightly pressed above the base;

s460, applying an excitation voltage signal with a slowly decreasing amplitude to an X-axis direction bending partition in the upper bidirectional stacked bending type piezoelectric driver, driving the upper driving foot to slowly swing to a limit position along the positive direction of an X axis by bending deformation of the upper bidirectional stacked bending type piezoelectric driver, and generating rotary displacement output around the negative direction of a Y axis by the rotor under the action of static friction force between the upper driving foot and the rotor;

s470, applying an excitation voltage signal with a rapidly rising amplitude to an X-axis direction bending partition in the upper bidirectional stacked bending type piezoelectric driver, wherein the upper bidirectional stacked bending type piezoelectric driver is bent and deformed to drive the upper driving foot to rapidly swing to an initial position along an X-axis direction, and under the action of inertia of the mover, the mover and the upper driving foot slide relatively to each other and are kept still;

s480, judging whether the rotor rotates by a specified displacement, if so, executing a step S490; otherwise, returning to step S460;

s490 stops rotating the mover,

when the rotor rotates around the X axis in the positive direction, the method comprises the following steps:

s500, pressing the rotor above the upper driving foot, adjusting the pre-pressure between the upper driving foot and the upper driving foot, pressing the middle driving foot on the side surface of the vertical supporting column, adjusting the pre-pressure between the upper driving foot and the lower driving foot, pressing the lower driving foot above the base, and adjusting the pre-pressure between the upper driving foot and the lower driving foot;

s510, applying slowly rising excitation voltage signals to Y-axis direction bending partitions in the upper bidirectional stacked bending piezoelectric driver, driving the upper driving foot to slowly swing to a limit position along a Y-axis direction by bending deformation of the upper bidirectional stacked bending piezoelectric driver, and generating rotary displacement output by the rotor around an X-axis positive direction under the action of static friction force between the upper driving foot and the rotor;

s520, applying an excitation voltage signal with a rapidly reduced amplitude to a Y-axis direction bending partition in the upper bidirectional stacked bending type piezoelectric driver, driving the upper driving foot to rapidly swing to an initial position along the positive direction of the Y axis by bending deformation of the upper bidirectional stacked bending type piezoelectric driver, and keeping the mover and the upper driving foot stationary by relative sliding under the action of inertia of the mover;

s530, judging whether the rotor rotates by a specified displacement, if so, executing a step S540; otherwise, returning to step S510;

s540 stops rotating the mover,

when the rotor rotates around the X axis in the opposite direction, the method comprises the following steps:

s550, pressing the rotor above the upper driving foot, adjusting the pre-pressure between the upper driving foot and the upper driving foot, pressing the middle driving foot on the side surface of the vertical supporting column, adjusting the pre-pressure between the upper driving foot and the lower driving foot, pressing the lower driving foot above the base, and adjusting the pre-pressure between the upper driving foot and the lower driving foot;

s560 applying a slowly decreasing amplitude excitation voltage signal to the Y-axis bending section of the upper bi-directional stacked bending piezoelectric actuator, where the upper bi-directional stacked bending piezoelectric actuator bends and deforms to drive the upper driving foot to slowly swing to a limit position along the Y-axis positive direction, and the mover generates rotational displacement output around the X-axis in the opposite direction under the effect of the static friction force between the upper driving foot and the mover;

s570 applying an excitation voltage signal with a rapidly increasing amplitude to the Y-axis direction bending section in the upper bi-directional stacked bending piezoelectric actuator, where the upper bi-directional stacked bending piezoelectric actuator bends and deforms to drive the upper driving foot to rapidly swing to an initial position along the Y-axis direction, and under the action of inertia of the mover, the mover and the upper driving foot slide relative to each other and remain stationary;

s580, judging whether the rotor rotates by a specified displacement, if so, executing a step S590; otherwise, returning to step S560;

s590 stops rotating the mover,

when the rotor rotates around the Z axis in the positive direction, the method comprises the following steps:

s600, pressing the rotor above the upper driving foot, adjusting the pre-pressure between the upper driving foot and the upper driving foot, pressing the middle driving foot on the side surface of the vertical supporting column, adjusting the pre-pressure between the upper driving foot and the lower driving foot, pressing the lower driving foot above the base, and adjusting the pre-pressure between the upper driving foot and the lower driving foot;

s610, applying an excitation voltage signal with slowly rising amplitude to the stacked torsional piezoelectric driver, driving the upper driving foot to slowly swing to a limit position around the positive direction of a Z axis by torsional deformation of the stacked torsional piezoelectric driver, and generating rotary displacement output around the positive direction of the Z axis by the rotor under the action of static friction force between the upper driving foot and the rotor;

s620, applying an excitation voltage signal with a rapidly reduced amplitude to the stacked torsional piezoelectric driver, wherein torsional deformation of the stacked torsional piezoelectric driver drives the upper side driving foot to rapidly swing to an initial position around a Z axis in an opposite direction, and under the action of inertia of the rotor, the rotor and the upper side driving foot slide relatively to each other and are kept still;

s630, judging whether the rotor rotates by a specified displacement, if so, executing the step S640; otherwise, returning to step S610;

s640 stops rotating the mover,

when the rotor rotates around the Z axis in the opposite direction, the method comprises the following steps:

s650, pressing the rotor above the upper driving foot, adjusting the pre-pressure between the upper driving foot and the upper driving foot, pressing the middle driving foot on the side surface of the vertical supporting column, adjusting the pre-pressure between the upper driving foot and the lower driving foot, pressing the lower driving foot above the base, and adjusting the pre-pressure between the upper driving foot and the lower driving foot;

s660, applying an excitation voltage signal with a slowly-decreasing amplitude to the stacked torsional piezoelectric driver, wherein torsional deformation of the stacked torsional piezoelectric driver drives the upper driving foot to slowly swing to a limit position around the Z axis in the opposite direction, and the rotor generates rotary displacement output around the Z axis in the opposite direction under the action of static friction force between the upper driving foot and the rotor;

s670, applying an excitation voltage signal with a rapidly rising amplitude to the stacked torsional piezoelectric driver, wherein torsional deformation of the stacked torsional piezoelectric driver drives the upper side driving foot to positively and rapidly swing to an initial position around the Z-axis direction, and under the action of inertia of the rotor, the rotor and the upper side driving foot slide relatively to each other and keep still;

s680, judging whether the rotor rotates by a specified displacement, if so, executing a step S690; otherwise, returning to step S660;

s690 stops rotating the mover.

The invention has the beneficial effects that: the invention discloses an ultra-precise six-degree-of-freedom piezoelectric motion platform, which can realize the stepping motion of a rotor by utilizing an excitation method in the invention, and can realize the large-stroke and high-resolution six-degree-of-freedom ultra-precise motion of the rotor by adjusting the motion step pitch, thereby completing the functions of omnibearing six-degree-of-freedom positioning and posture adjustment in space. Compared with a multi-degree-of-freedom piezoelectric driver adopting a direct driving mode, the piezoelectric driving platform disclosed by the invention realizes a larger movement stroke by utilizing a stepping driving mode; compared with a multi-degree-of-freedom piezoelectric driver adopting a multi-stage series stepping driving mode, the piezoelectric motion platform disclosed by the invention has the advantages that the parallel and overlapped structure is utilized, the structure is greatly simplified, and the size is reduced; the stacked piezoelectric driver is used as a driving element, and the piezoelectric motion platform can realize larger load capacity; by utilizing the excitation method, the excitation signal is simple and easy to implement, the driving step pitch is convenient to adjust, and the driving effect is stable and reliable. Based on the reasons, the piezoelectric motion platform and the excitation method thereof can meet the application requirements in the technical fields of micro-nano operation, micro life science, ultra-precision machining and the like, improve the degree of freedom of the ultra-precision piezoelectric motion platform, enrich the configuration design of the ultra-precision multi-degree-of-freedom piezoelectric driver, widen the application range of the piezoelectric driver, have important practical significance on the development of the ultra-precision multi-degree-of-freedom piezoelectric driving technology and theory, have wide application prospects in the technical fields of ultra-precision instruments and equipment and the like, and have important practical significance and promotion effect on the development of the ultra-precision multi-degree-freedom piezoelectric driving technology and theory.

Drawings

FIG. 1 is a schematic three-dimensional structure diagram of an ultra-precise six-degree-of-freedom piezoelectric motion platform;

FIG. 2 is a schematic diagram of bending deformation of an upper-side bidirectional stacked bending piezoelectric actuator of a four-DOF driving unit in an ultra-precise six-DOF piezoelectric motion platform along the Y-axis direction;

FIG. 3 is a schematic diagram of bending deformation of an upper-side bidirectional stacked bending piezoelectric actuator of a four-DOF driving unit in an ultra-precise six-DOF piezoelectric motion platform along the X-axis direction;

fig. 4 is a schematic diagram of torsional deformation of a stacked torsional piezoelectric driver of a four-degree-of-freedom driving unit in an ultra-precise six-degree-of-freedom piezoelectric motion platform around the Z-axis direction;

FIG. 5 is a schematic diagram of the telescopic deformation of a stacked linear piezoelectric actuator of a four-DOF driving unit in an ultra-precise six-DOF piezoelectric motion platform along the Z-axis direction;

FIG. 6 is a schematic diagram of bending deformation of a two-way stacked bending piezoelectric actuator under a two-degree-of-freedom driving unit in an ultra-precise six-degree-of-freedom piezoelectric motion platform along the Y-axis direction;

FIG. 7 is a schematic diagram of bending deformation of a two-way stacked bending piezoelectric actuator under a two-degree-of-freedom driving unit in an ultra-precise six-degree-of-freedom piezoelectric motion platform along the X-axis direction;

fig. 8 is a schematic diagram of excitation voltage signals required to be applied to each stacked piezoelectric actuator when the ultra-precise six-degree-of-freedom piezoelectric motion platform realizes ultra-precise forward linear or rotational motion;

fig. 9 is a schematic diagram of excitation voltage signals required to be applied to each stacked piezoelectric actuator when the ultra-precise six-degree-of-freedom piezoelectric motion platform realizes ultra-precise reverse linear or rotational motion;

fig. 10 is a schematic diagram of a motion trajectory of a point at the end of each driving foot relative to a contact plane when the ultra-precise six-degree-of-freedom piezoelectric motion platform realizes ultra-precise forward and reverse linear or rotational motion.

The piezoelectric actuator comprises a rotor 1, a four-degree-of-freedom driving unit 2, an upper side driving foot 2-1, an upper side bidirectional stacked bending piezoelectric actuator 2-2, an insulating layer 2-3, a stacked torsion type piezoelectric actuator 2-4, a guide clamping plate 2-5, a stacked linear piezoelectric actuator 2-6, a middle driving foot 2-7, a vertical supporting column 3, a vertical guiding rail 4, a transverse guiding rail 5, a longitudinal guiding rail 6, a two-degree-of-freedom driving unit 7-1, a supporting clamping plate 7-2, a lower side bidirectional stacked bending type piezoelectric actuator 7-3, and a base 8.

Detailed Description

The technical solutions in the embodiments of the present invention will be described clearly and completely with reference to the accompanying drawings in the embodiments of the present invention, and it is obvious that the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.

Referring to the attached drawings 1-7, the invention provides an embodiment of an ultra-precise six-degree-of-freedom piezoelectric motion platform, which comprises a mover 1, a four-degree-of-freedom driving unit 2, a vertical supporting column 3, a vertical guide rail 4, a transverse guide rail 5, a longitudinal guide rail 6, a two-degree-of-freedom driving unit 7 and a base 8; the four-degree-of-freedom driving unit 2 comprises an upper side driving foot 2-1, an upper side bidirectional stacked bending piezoelectric driver 2-2, an insulating layer 2-3, a stacked torsion type piezoelectric driver 2-4, a guide splint 2-5, a stacked linear piezoelectric driver 2-6 and a middle driving foot 2-7; the two-degree-of-freedom driving unit 7 comprises a supporting splint 7-1, a lower side bidirectional stacked bending piezoelectric driver 7-2 and a lower side driving foot 7-3; the upper side driving foot 2-1, the upper side bidirectional stacked bending type piezoelectric driver 2-2, the insulating layer 2-3, the stacked torsion type piezoelectric driver 2-4, the guide clamping plate 2-5, the stacked linear type piezoelectric driver 2-6 and the middle driving foot 2-7 are sequentially connected from top to bottom, and the top end of the vertical supporting column 3 supports the middle driving foot 2-7; the vertical supporting column 3, the supporting splint 7-1, the lower-side bidirectional stacked bending piezoelectric driver 7-2 and the lower-side driving foot 7-3 are sequentially connected from top to bottom; the rotor 1 is tightly pressed on the top surface of the upper side driving foot 2-1, the middle driving foot 2-7 is tightly pressed on the side surface of the vertical supporting column 3, and the lower end of the lower side driving foot 7-3 is tightly pressed on the upper surface of the base 8; the vertical guide rail 4 is arranged along the vertical direction, and the transverse guide rail 5 and the longitudinal guide rail 6 are respectively arranged along the horizontal direction and the depth direction; the supporting clamp plate 7-1 is fixedly connected with the vertical guide rail 4, the guide clamp plates 2-5 are slidably connected with the vertical guide rail 4, the supporting clamp plate 7-1 is slidably connected with the longitudinal guide rail 6, the longitudinal guide rail 6 is slidably connected with the transverse guide rail 5 and is arranged in a crossed manner, and the transverse guide rail 5 is fixedly connected with the base 8; the base 8 is fixed, and the rotor 1 outputs spatial six-degree-of-freedom motion.

Specifically, the present embodiment is further described in detail with reference to fig. 1 to 7 of the specification. The vertical guide rails 4 are arranged along the Z-axis direction to ensure the linear motion of the guide clamping plates 2-5 along the direction, at least two vertical guide rails 4 are arranged and are respectively arranged on the diagonal side of the support clamping plate 7-1 to ensure that the four-degree-of-freedom driving unit 2 can stably move along the vertical guide rails 4, and the transverse guide rails 5 and the longitudinal guide rails 6 are respectively arranged along the Y-axis direction and the X-axis direction to ensure the linear motion of the support clamping plate 7-1 along the two directions; the rotor 1 is pressed above the upper driving foot 2-1 in a contact mode, the middle driving foot 2-7 is pressed on the side face of the vertical supporting column 3 in a contact mode, the lower driving foot 7-3 is pressed above the base 8 in a contact mode, and the rotor 1, the guide clamping plate 2-5 and the supporting clamping plate 7-1 are driven to move ultraprecisely by friction force among the upper driving foot, the middle driving foot and the lower driving foot respectively; the base 8 is kept fixed to support all other components, the supporting splint 7-1 generates linear motion along the Y-axis direction and the X-axis direction relative to the base 8 under the action of the support of the transverse guide rails 5 and the longitudinal guide rails 6 and the friction force between the lower side driving foot 7-3 and the base 8, the guiding splint 2-5 generates linear motion along the Z-axis direction relative to the supporting splint 7-1 under the action of the guide of the vertical guide rails 4 and the friction force between the middle driving foot 2-7 and the vertical supporting column 3, the mover 1 generates rotary motion around the Y-axis direction, the X-axis direction and the Z-axis direction relative to the upper side driving foot 2-1 under the action of the support of the upper side driving foot 2-1 and the friction force between the upper side driving foot 2-1 and the mover 1, the six-degree-of-freedom spatial motion of the mover 1 relative to the base 8 can be realized through the synthesis of the motions; the mover 1 is used for fixing a precision operation object or a tail end actuating mechanism and outputting ultra-precision six-degree-of-freedom motion relative to the base 8, and specifically comprises linear motion in three orthogonal directions of a Y-axis direction, an X-axis direction and a Z-axis direction in space and rotary motion in the three orthogonal directions of the Y-axis direction, the X-axis direction and the Z-axis direction bypassing the center of the mover 1, so that ultra-precision positioning and posture adjusting motion of the precision operation object or the tail end actuating mechanism is realized.

Referring to fig. 1-7, in this preferred embodiment, the upper driving foot 2-1 realizes automatic centering of the mover 1 by means of positioning holes, the mover 1 is pressed above the upper driving foot 2-1 under the action of its own gravity and load, and the mover 1 can not only make three-axis rotational motion around its own center but also make three-degree-of-freedom linear motion in space along with the upper driving foot 2-1 under the action of the upper driving foot 2-1; the insulating layer 2-3 is used for preventing the electrical connection between the upper-side bidirectional stacked bending piezoelectric driver 2-2 and the stacked torsion piezoelectric driver 2-4 so as to ensure the electrical safety of the two drivers; the vertical guide rail 4, the transverse guide rail 5 and the longitudinal guide rail 6 limit the motion forms of the four-degree-of-freedom driving unit 2 and the two-degree-of-freedom driving unit 7 under the matching action of the guide clamping plates 2-5 and the support clamping plates 7-1, and respectively press the middle driving feet 2-7 and the lower side driving feet 7-3 on the vertical support column 3 and the base 8; the middle driving feet 2-7 are tightly pressed on the side surfaces of the vertical supporting columns 3, and under the interaction between the middle driving feet and the vertical supporting columns, the guide clamping plates 2-5 can do linear motion along the Z-axis direction and can also do linear motion along the Y-axis direction and the X-axis direction along with the supporting clamping plates 7-1; the lower side driving foot 7-3 is tightly pressed above the base 8, and under the mutual action of the lower side driving foot and the base, the supporting splint 7-1 can do linear motion along the Y-axis direction and the X-axis direction in the motion plane.

Referring to fig. 1 to 7, in the present preferred embodiment, the four-degree-of-freedom driving unit 2 and the two-degree-of-freedom driving unit 7 are used as energy conversion elements to convert input electric energy into output mechanical energy.

Referring to fig. 1-7, in the present preferred embodiment, the upper driving foot 2-1 is provided with positioning holes, which are matched with the mover 1, and the mover 1 is pressed against the top surface of the upper driving foot 2-1 through the positioning holes; the bottom of the middle driving foot 2-7 is provided with a fixing hole for fixing the vertical supporting column 3, the fixing hole is matched with the vertical supporting column 3, and the middle driving foot 2-7 is tightly pressed on the side surface of the vertical supporting column 3 through the fixing hole.

Referring to fig. 1 to 7, in the preferred embodiment of this section, the upper bidirectional stacked bending piezoelectric actuator 2-2 and the lower bidirectional stacked bending piezoelectric actuator 7-2 are respectively formed by sequentially and fixedly connecting a plurality of piezoelectric ceramic plates along the axial direction of the four-degree-of-freedom driving unit 2 and the two-degree-of-freedom driving unit 7, and each piezoelectric ceramic plate includes four polarization sections. One pair of the bending subareas is an X-axis direction bending subarea, and the other pair of the bending subareas is a Y-axis direction bending subarea; the bending deformation of the upper bidirectional stacked bending piezoelectric driver 2-2 and the lower bidirectional stacked bending piezoelectric driver 7-2 under the excitation signal respectively drives the upper driving foot 2-1 and the lower driving foot 7-3 to do reciprocating swing motion along the Y-axis direction and the X-axis direction; the deformation diagrams of the upper-side bidirectional stacked bending type piezoelectric actuator 2-2 in bending along the Y-axis direction and in bending along the X-axis direction are shown in fig. 2 and 3, respectively, and the deformation diagrams of the lower-side bidirectional stacked bending type piezoelectric actuator 7-2 in bending along the Y-axis direction and in bending along the X-axis direction are shown in fig. 6 and 7, respectively.

Referring to fig. 1-7, in the preferred embodiment of this section, the stacked linear piezoelectric actuator 2-6 is formed by fixedly connecting multiple piezoelectric ceramic plates along the axial direction of the four-degree-of-freedom driving unit 2, and each piezoelectric ceramic plate has only one polarization partition; the telescopic deformation of the laminated linear piezoelectric actuator 2-6 under the excitation signal drives the middle driving foot 2-7 to do reciprocating linear motion along the Z-axis direction; the deformation diagram of the stacked linear piezoelectric actuators 2-6 extending and contracting in the Z-axis direction is shown in fig. 5.

Referring to fig. 1-7, in the preferred embodiment of this section, the stacked torsional piezoelectric actuator 2-4 is formed by fixedly connecting a plurality of piezoelectric ceramic plates around the axial direction of the four-degree-of-freedom driving unit 2, and each piezoelectric ceramic plate has only one partition; torsional deformation of the laminated torsional piezoelectric driver 2-4 under an excitation signal drives the upper side driving foot 2-1 to do reciprocating rotation motion around the Z-axis direction; fig. 4 shows a schematic diagram of the deformation of the laminated torsion type piezoelectric actuator 2-4 in torsion about the Z-axis direction.

Specifically, in this embodiment, in this preferred embodiment, the number of two-degree-of-freedom drive units 7 is one, but if the number of two-degree-of-freedom drive units 7 is increased, a similar excitation method is also applicable, and multiplication of the load capacity can be achieved.

An excitation method of an ultra-precise six-degree-of-freedom piezoelectric motion platform is applied to the ultra-precise six-degree-of-freedom piezoelectric motion platform in part of preferred embodiments and is provided with

The axis direction of the four-degree-of-freedom driving unit 2 is a Z axis, and the clockwise direction of the Z axis is a positive direction;

the depth direction orthogonal to the axial direction of the four-degree-of-freedom drive unit 2 is an X axis, and the clockwise direction of the X axis is a positive direction;

the horizontal direction orthogonal to the axial direction of the four-degree-of-freedom drive unit 2 is the Y axis, the clockwise direction of the Y axis is the positive direction,

when the mover 1 makes a straight-line motion in the positive direction along the Y axis, the method comprises the following steps:

s100, pressing the rotor 1 onto the top surface of the upper driving foot 2-1, adjusting the pre-pressure between the upper driving foot and the upper driving foot, pressing the middle driving foot 2-7 onto the side surface of the vertical supporting column 3, adjusting the pre-pressure between the upper driving foot and the lower driving foot, pressing the lower driving foot 7-3 onto the upper surface of the base 8, and adjusting the pre-pressure between the upper driving foot and the lower driving foot;

s110, applying an excitation voltage signal with slowly rising amplitude to a Y-axis direction bending partition in the lower-side bidirectional stacked bending type piezoelectric driver 7-2, driving the lower-side driving foot 7-3 to slowly swing to a limit position along a Y-axis direction by bending deformation of the lower-side bidirectional stacked bending type piezoelectric driver 7-2, and generating linear displacement along the Y-axis positive direction by the two-degree-of-freedom driving unit 7 and the four-degree-of-freedom driving unit 2 under the action of static friction force between the lower-side driving foot 7-3 and the base 8 so as to drive the rotor 1 to generate linear displacement output along the Y-axis positive direction;

s120, applying an excitation voltage signal with a rapidly reduced amplitude to a Y-axis direction bending partition in the lower bidirectional stacked bending type piezoelectric driver 7-2, enabling the lower bidirectional stacked bending type piezoelectric driver 7-2 to bend and deform to drive the lower driving foot 7-3 to rapidly swing to an initial position along the positive direction of the Y axis, and under the action of inertia of the two-degree-of-freedom driving unit 7 and the four-degree-of-freedom driving unit 2, enabling the lower driving foot 7-3 and the base 8 to slide relatively to keep still, so that the rotor 1 also keeps still;

s130, judging whether the mover 1 moves by a specified displacement, if so, executing the step S140; otherwise, returning to step S110;

s140 stops moving the mover 1,

by changing the amplitude and time of the excitation voltage signal applied to the Y-axis direction bending component in the lower-side bidirectional stacked bending type piezoelectric driver 7-2 as shown by U in fig. 8, ultra-precise motion in this direction can be realized.

When the mover 1 makes a reverse direction linear motion along the Y-axis, the method includes the following steps:

s150, pressing the rotor 1 onto the top surface of the upper driving foot 2-1, adjusting the pre-pressure between the upper driving foot and the upper driving foot, pressing the middle driving foot 2-7 onto the side surface of the vertical supporting column 3, adjusting the pre-pressure between the upper driving foot and the lower driving foot, pressing the lower driving foot 7-3 onto the upper surface of the base 8, and adjusting the pre-pressure between the upper driving foot and the lower driving foot;

s160, applying an excitation voltage signal with a slowly decreasing amplitude to a Y-axis direction bending partition in the lower-side bidirectional stacked bending type piezoelectric driver 7-2, enabling the lower-side bidirectional stacked bending type piezoelectric driver 7-2 to be bent and deformed to drive the lower-side driving foot 7-3 to slowly swing to a limit position along the positive direction of the Y axis, and enabling the two-degree-of-freedom driving unit 7 and the four-degree-of-freedom driving unit 2 to generate linear displacement along the negative direction of the Y axis under the action of static friction force between the lower-side driving foot 7-3 and the base 8, so as to drive the rotor 1 to generate linear displacement output along the negative direction of the Y axis;

s170, applying an excitation voltage signal with a rapidly rising amplitude to a Y-axis direction bending partition in the lower bidirectional stacked bending type piezoelectric driver 7-2, enabling the lower bidirectional stacked bending type piezoelectric driver 7-2 to bend and deform to drive the lower driving foot 7-3 to rapidly swing to an initial position along the Y-axis direction, and under the action of inertia of the two-degree-of-freedom driving unit 7 and the four-degree-of-freedom driving unit 2, enabling the lower driving foot 7-3 and the base 8 to slide relatively to keep still, so that the mover 1 also keeps still;

s180, judging whether the mover 1 moves by the specified displacement, if so, executing a step S190; otherwise, returning to step S160;

s190 stops moving the mover 1,

by changing the amplitude and time of the excitation voltage signal applied to the Y-axis direction bending component in the lower-side bidirectional stacked bending type piezoelectric driver 7-2 as shown by U in fig. 9, ultra-precise motion in this direction can be realized.

When the mover 1 makes a straight line motion in the positive direction along the X-axis, the method comprises the following steps:

s200, pressing the rotor 1 above the upper driving foot 2-1, adjusting the pre-pressure between the upper driving foot and the lower driving foot, pressing the middle driving foot 2-7 on the side surface of the vertical supporting column 3, adjusting the pre-pressure between the upper driving foot and the lower driving foot, pressing the lower driving foot 7-3 above the base 8, and adjusting the pre-pressure between the upper driving foot and the lower driving foot;

s210, applying an excitation voltage signal with a slowly rising amplitude to an X-axis direction bending partition in the lower-side bidirectional stacked bending type piezoelectric driver 7-2, driving the lower-side driving foot 7-3 to slowly swing to a limit position along an X-axis direction by bending deformation of the lower-side bidirectional stacked bending type piezoelectric driver 7-2, and generating linear displacement along the X-axis positive direction by the two-degree-of-freedom driving unit 7 and the four-degree-of-freedom driving unit 2 under the action of static friction force between the lower-side driving foot 7-3 and the base 8 so as to drive the rotor 1 to generate linear displacement output along the X-axis positive direction;

s220, applying an excitation voltage signal with a rapidly reduced amplitude to an X-axis direction bending partition in the lower bidirectional stacked bending type piezoelectric driver 7-2, enabling the lower bidirectional stacked bending type piezoelectric driver 7-2 to bend and deform to drive the lower driving foot 7-3 to rapidly swing to an initial position along the X-axis positive direction, and under the action of inertia of the two-degree-of-freedom driving unit 7 and the four-degree-of-freedom driving unit 2, enabling the lower driving foot 7-3 and the base 8 to slide relatively to keep still, so that the rotor 1 also keeps still;

s230, judging whether the mover 1 moves by a specified displacement, if so, executing the step S240; otherwise, returning to step S210;

s240 stops moving the mover 1,

by changing the amplitude and time of the excitation voltage signal applied to the X-axis direction bending component in the lower-side bidirectional stacked bending type piezoelectric driver 7-2 as shown by U in fig. 8, ultra-precise motion in this direction can be realized.

When the mover 1 makes a reverse linear motion along the X-axis, the method includes the following steps:

s250, pressing the rotor 1 above the upper driving foot 2-1, adjusting the pre-pressure between the upper driving foot and the lower driving foot, pressing the middle driving foot 2-7 on the side surface of the vertical supporting column 3, adjusting the pre-pressure between the upper driving foot and the lower driving foot, pressing the lower driving foot 7-3 above the base 8, and adjusting the pre-pressure between the upper driving foot and the lower driving foot;

s260, applying an excitation voltage signal with a slowly-decreasing amplitude to an X-axis bending partition in the lower bidirectional stacked bending piezoelectric driver 7-2, enabling the lower bidirectional stacked bending piezoelectric driver 7-2 to be bent and deformed to drive the lower driving foot 7-3 to slowly swing to a limit position along the positive direction of the X axis, and enabling the two-degree-of-freedom driving unit 7 and the four-degree-of-freedom driving unit 2 to generate linear displacement along the negative direction of the X axis under the action of static friction force between the lower driving foot 7-3 and the base 8, so as to drive the rotor 1 to generate linear displacement output along the negative direction of the X axis;

s270, applying an excitation voltage signal with a rapidly rising amplitude to an X-axis direction bending partition in the lower bidirectional stacked bending type piezoelectric driver 7-2, enabling the lower bidirectional stacked bending type piezoelectric driver 7-2 to bend and deform to drive the lower driving foot 7-3 to rapidly swing to an initial position along the X-axis direction, and under the action of inertia of the two-degree-of-freedom driving unit 7 and the four-degree-of-freedom driving unit 2, enabling the lower driving foot 7-3 and the base 8 to slide relatively to keep still, so that the rotor 1 also keeps still;

s280, judging whether the mover 1 moves by the specified displacement, if so, executing the step S290; otherwise, returning to step S260;

s290 stops moving the mover 1,

by changing the amplitude and time of the excitation voltage signal applied to the X-axis direction bending component in the lower-side bidirectional stacked bending type piezoelectric driver 7-2 as shown by U in fig. 9, ultra-precise motion in this direction can be realized.

When the mover 1 makes a straight-line motion in the positive direction along the Z axis, the method comprises the following steps:

s300, pressing the rotor 1 above the upper driving foot 2-1, adjusting the pre-pressure between the upper driving foot and the lower driving foot, pressing the middle driving foot 2-7 on the side surface of the vertical supporting column 3, adjusting the pre-pressure between the upper driving foot and the lower driving foot, pressing the lower driving foot 7-3 above the base 8, and adjusting the pre-pressure between the upper driving foot and the lower driving foot;

s310, applying an excitation voltage signal with a slowly rising amplitude to the stacked linear piezoelectric actuator 2-6, driving the middle driving foot 2-7 to slowly move to an extreme position along the Z-axis reverse direction through the telescopic deformation of the stacked linear piezoelectric actuator 2-6, and generating linear displacement along the Z-axis positive direction by the four-degree-of-freedom driving unit 2 under the action of static friction force between the middle driving foot 2-7 and the vertical supporting column 3 so as to drive the rotor 1 to generate linear displacement output along the Z-axis positive direction;

s320, applying an excitation voltage signal with a rapidly-reduced amplitude to the stacked linear piezoelectric actuator 2-6, driving the middle driving foot 2-7 to rapidly move to an extreme position along the positive direction of the Z axis by the telescopic deformation of the stacked linear piezoelectric actuator 2-6, and keeping the middle driving foot 2-7 and the vertical supporting column 3 stationary due to relative sliding under the action of inertia of the four-degree-of-freedom driving unit 2, so that the rotor 1 also keeps stationary;

s330, judging whether the mover 1 moves by the specified displacement, if so, executing the step S340; otherwise, returning to step S310;

s340 stops moving the mover 1,

by varying the amplitude and time of the excitation voltage signal, shown as U in fig. 8, applied to the stacked linear piezoelectric actuators 2-6, ultra-precise motion in this direction can be achieved.

When the mover 1 makes a reverse direction linear motion along the Z-axis, the method comprises the following steps:

s350, the rotor 1 is tightly pressed above the upper driving foot 2-1, the pre-pressure between the upper driving foot and the lower driving foot is adjusted, the middle driving foot 2-7 is tightly pressed on the side face of the vertical supporting column 3, the pre-pressure between the upper driving foot and the lower driving foot is adjusted, the lower driving foot 7-3 is tightly pressed above the base 8, and the pre-pressure between the upper driving foot and the lower driving foot is adjusted;

s360, applying an excitation voltage signal with a slowly-reduced amplitude to the stacked linear piezoelectric actuator 2-6, driving the middle driving foot 2-7 to slowly move to an extreme position along the positive direction of the Z axis by the telescopic deformation of the stacked linear piezoelectric actuator 2-6, and generating linear displacement along the negative direction of the Z axis by the four-degree-of-freedom driving unit 2 under the action of static friction force between the middle driving foot 2-7 and the vertical supporting column 3 so as to drive the rotor 1 to generate linear displacement output along the negative direction of the Z axis;

s370, applying an excitation voltage signal with a rapidly rising amplitude to the stacked linear piezoelectric actuator 2-6, enabling the stacked linear piezoelectric actuator 2-6 to stretch and deform to drive the middle driving foot 2-7 to rapidly move to an extreme position along the Z-axis direction, and under the action of inertia of the four-degree-of-freedom driving unit 2, enabling the middle driving foot 2-7 and the vertical supporting column 3 to slide relatively to keep still, and further enabling the rotor 1 to keep still;

s380, judging whether the mover 1 moves by a specified displacement, if so, executing the step S390; otherwise, returning to step S360;

s390 stops moving the mover 1,

by varying the amplitude and time of the excitation voltage signal, shown as U in fig. 9, applied to the stacked linear piezoelectric actuators 2-6, ultra-precise motion in this direction can be achieved.

When the mover 1 rotates around the Y axis in the positive direction, the method comprises the following steps:

s400, pressing the rotor 1 above the upper driving foot 2-1, adjusting the pre-pressure between the upper driving foot and the lower driving foot, pressing the middle driving foot 2-7 on the side surface of the vertical supporting column 3, adjusting the pre-pressure between the upper driving foot and the lower driving foot, pressing the lower driving foot 7-3 above the base 8, and adjusting the pre-pressure between the upper driving foot and the lower driving foot;

s410, applying slowly rising excitation voltage signals to X-axis direction bending partitions in the upper bidirectional stacked bending piezoelectric driver 2-2, driving the upper driving foot 2-1 to slowly swing to a limit position along the X-axis direction by bending deformation of the upper bidirectional stacked bending piezoelectric driver 2-2, and generating rotary displacement output by the rotor 1 around the Y-axis positive direction under the action of static friction force between the upper driving foot 2-1 and the rotor 1;

s420, applying an excitation voltage signal with a rapidly reduced amplitude to an X-axis direction bending partition in the upper bidirectional stacked bending type piezoelectric driver 2-2, enabling the upper bidirectional stacked bending type piezoelectric driver 2-2 to bend and deform to drive the upper driving foot 2-1 to rapidly swing to an initial position along the X-axis positive direction, and enabling the mover 1 and the upper driving foot 2-1 to relatively slide and keep static under the action of inertia of the mover 1;

s430, judging whether the mover 1 rotates by a specified displacement, if so, executing the step S440; otherwise, returning to step S410;

s440 stops rotating the mover 1,

by changing the amplitude and time of the excitation voltage signal applied to the X-axis direction bending component in the upper-side bidirectional stacked bending type piezoelectric driver 2-2 as shown by U in fig. 8, ultra-precise motion in this direction can be realized.

When the mover 1 performs reverse rotation motion around the Y axis, the method comprises the following steps:

s450, the rotor 1 is tightly pressed above the upper driving foot 2-1, the pre-pressure between the upper driving foot and the lower driving foot is adjusted, the middle driving foot 2-7 is tightly pressed on the side surface of the vertical supporting column 3, the pre-pressure between the upper driving foot and the lower driving foot is adjusted, the lower driving foot 7-3 is tightly pressed above the base 8, and the pre-pressure between the upper driving foot and the lower driving foot is adjusted;

s460, applying an excitation voltage signal with a slowly decreasing amplitude to an X-axis direction bending partition in the upper bidirectional stacked bending type piezoelectric driver 2-2, driving the upper driving foot 2-1 to slowly swing to a limit position along the X-axis positive direction through bending deformation of the upper bidirectional stacked bending type piezoelectric driver 2-2, and generating rotary displacement output by the rotor 1 around the Y-axis in the opposite direction under the action of static friction force between the upper driving foot 2-1 and the rotor 1;

s470, applying an excitation voltage signal with a rapidly rising amplitude to an X-axis direction bending partition in the upper bidirectional stacked bending type piezoelectric driver 2-2, enabling the upper bidirectional stacked bending type piezoelectric driver 2-2 to bend and deform to drive the upper driving foot 2-1 to rapidly swing to an initial position along the X-axis direction, and enabling the mover 1 and the upper driving foot 2-1 to relatively slide and keep static under the action of inertia of the mover 1;

s480, judging whether the rotor 1 rotates by the specified displacement, if so, executing a step S490; otherwise, returning to step S460;

s490 stops rotating the mover 1,

by changing the amplitude and time of the excitation voltage signal applied to the X-axis direction bending component in the upper-side bidirectional stacked bending type piezoelectric driver 2-2 as shown by U in fig. 9, ultra-precise motion in this direction can be realized.

When the mover 1 rotates around the X axis in the positive direction, the method comprises the following steps:

s500, pressing the rotor 1 above the upper driving foot 2-1, adjusting the pre-pressure between the upper driving foot and the lower driving foot, pressing the middle driving foot 2-7 on the side surface of the vertical supporting column 3, adjusting the pre-pressure between the upper driving foot and the lower driving foot, pressing the lower driving foot 7-3 above the base 8, and adjusting the pre-pressure between the upper driving foot and the lower driving foot;

s510, applying slowly rising excitation voltage signals to Y-axis direction bending subareas in the upper bidirectional stacked bending piezoelectric actuator 2-2, enabling the upper bidirectional stacked bending piezoelectric actuator 2-2 to be bent and deformed to drive the upper driving foot 2-1 to slowly swing to a limit position along the Y-axis direction, and enabling the rotor 1 to generate rotary displacement output around the X-axis direction under the action of static friction force between the upper driving foot 2-1 and the rotor 1;

s520, applying an excitation voltage signal with a rapidly reduced amplitude to a Y-axis direction bending partition in the upper bidirectional stacked bending type piezoelectric driver 2-2, enabling the upper bidirectional stacked bending type piezoelectric driver 2-2 to bend and deform to drive the upper driving foot 2-1 to rapidly swing to an initial position along the positive direction of the Y axis, and enabling the mover 1 and the upper driving foot 2-1 to relatively slide and keep static under the action of inertia of the mover 1;

s530, judging whether the rotor 1 rotates by a specified displacement, if so, executing a step S540; otherwise, returning to step S510;

s540 stops rotating the mover 1,

by changing the amplitude and time of the excitation voltage signal applied to the Y-axis direction bending component in the upper-side bidirectional stacked bending type piezoelectric driver 2-2 as shown by U in fig. 8, ultra-precise motion in this direction can be realized.

When the rotor 1 rotates around the X axis in the opposite direction, the method comprises the following steps:

s550, pressing the rotor 1 above the upper driving foot 2-1, adjusting the pre-pressure between the upper driving foot and the lower driving foot, pressing the middle driving foot 2-7 on the side surface of the vertical supporting column 3, adjusting the pre-pressure between the upper driving foot and the lower driving foot, pressing the lower driving foot 7-3 above the base 8, and adjusting the pre-pressure between the upper driving foot and the lower driving foot;

s560, applying an excitation voltage signal with a slowly decreasing amplitude to a Y-axis direction bending partition in the upper bidirectional stacked bending piezoelectric driver 2-2, driving the upper driving foot 2-1 to slowly swing to a limit position along the Y-axis positive direction by bending deformation of the upper bidirectional stacked bending piezoelectric driver 2-2, and generating rotary displacement output by the rotor 1 around the X-axis in the opposite direction under the action of static friction force between the upper driving foot 2-1 and the rotor 1;

s570, applying an excitation voltage signal with a rapidly rising amplitude to a Y-axis direction bending partition in the upper bidirectional stacked bending type piezoelectric driver 2-2, enabling the upper bidirectional stacked bending type piezoelectric driver 2-2 to bend and deform to drive the upper driving foot 2-1 to rapidly swing to an initial position along the Y-axis direction, and enabling the mover 1 and the upper driving foot 2-1 to relatively slide and keep static under the action of inertia of the mover 1;

s580 determines whether the mover 1 has rotated by a specified displacement, and if so, executes step S590; otherwise, returning to step S560;

s590 stops rotating the mover 1,

by changing the amplitude and time of the excitation voltage signal applied to the Y-axis direction bending component in the upper-side bidirectional stacked bending type piezoelectric driver 2-2 as shown by U in fig. 9, ultra-precise motion in this direction can be realized.

When the rotor 1 rotates around the Z axis in the positive direction, the method comprises the following steps:

s600, pressing the rotor 1 above the upper driving foot 2-1, adjusting the pre-pressure between the upper driving foot and the lower driving foot, pressing the middle driving foot 2-7 on the side surface of the vertical supporting column 3, adjusting the pre-pressure between the upper driving foot and the lower driving foot, pressing the lower driving foot 7-3 above the base 8, and adjusting the pre-pressure between the upper driving foot and the lower driving foot;

s610, applying an excitation voltage signal with slowly rising amplitude to the laminated torsional type piezoelectric driver 2-4, driving the upper side driving foot 2-1 to slowly swing to a limit position around the positive direction of the Z axis by torsional deformation of the excitation voltage signal, and generating rotary displacement output by the rotor 1 around the positive direction of the Z axis under the action of static friction force between the upper side driving foot 2-1 and the rotor 1;

s620, applying an excitation voltage signal with a rapidly reduced amplitude to the stacked torsional piezoelectric driver 2-4, driving the upper side driving foot 2-1 to rapidly swing to an initial position around a Z axis in an opposite direction by torsional deformation of the stacked torsional piezoelectric driver 2-4, and keeping the rotor 1 and the upper side driving foot 2-1 static by relative sliding under the action of inertia of the rotor 1;

s630, judging whether the mover 1 rotates by a specified displacement, if so, executing the step S640; otherwise, returning to step S610;

s640 stops rotating the mover 1,

by changing the amplitude and time of the excitation voltage signal, which is applied to the laminated torsion type piezoelectric drivers 2-4 as indicated by U in fig. 8, ultra-precise motion in this direction can be achieved.

When the rotor 1 rotates around the Z axis in the opposite direction, the method comprises the following steps:

s650, pressing the rotor 1 above the upper driving foot 2-1, adjusting the pre-pressure between the upper driving foot and the lower driving foot, pressing the middle driving foot 2-7 on the side surface of the vertical supporting column 3, adjusting the pre-pressure between the upper driving foot and the lower driving foot, pressing the lower driving foot 7-3 above the base 8, and adjusting the pre-pressure between the upper driving foot and the lower driving foot;

s660, applying an excitation voltage signal with a slowly-reduced amplitude to the stacked torsional piezoelectric driver 2-4, driving the upper side driving foot 2-1 to slowly swing to a limit position around the Z axis in the opposite direction through torsional deformation of the stacked torsional piezoelectric driver 2-4, and generating rotary displacement output around the Z axis in the opposite direction by the rotor 1 under the action of static friction force between the upper side driving foot 2-1 and the rotor 1;

s670, applying an excitation voltage signal with a rapidly rising amplitude to the stacked torsional piezoelectric driver 2-4, driving the upper side driving foot 2-1 to rapidly swing to an initial position around the positive direction of the Z axis by torsional deformation of the stacked torsional piezoelectric driver 2-4, and keeping the rotor 1 and the upper side driving foot 2-1 stationary due to relative sliding under the action of inertia of the rotor 1;

s680, judging whether the rotor 1 rotates by a specified displacement, if so, executing a step S690; otherwise, returning to step S660;

s690 stops rotating the mover 1,

by changing the amplitude and time of the excitation voltage signal, which is applied to the laminated torsion type piezoelectric drivers 2-4 as indicated by U in fig. 9, ultra-precise motion in this direction can be achieved.

Specifically, in the present embodiment, when the motion platform realizes ultra-precise motion, the motion trajectories of the end mass point of the upper driving foot 2-1 with respect to the development plane of the mover 1, the development plane of the end mass point of the middle driving foot 2-7 with respect to the vertical support column 3, and the end mass point of the lower driving foot 7-3 with respect to the plane of the base 8 are as shown in fig. 10, and the ultra-precise six-degree-of-freedom forward and reverse motion of the mover 1 is realized by using the difference between two directional velocities.

The invention can realize all-around positioning and posture adjusting movement in space. By utilizing the stepping driving principle, a larger motion stroke and ultrahigh resolution can be realized simultaneously; the driving units with a plurality of degrees of freedom are connected in parallel and are arranged in the same way along the axial direction of the motion platform, so that the overall radial size of the motion platform is greatly reduced, the structure is simplified, and the compactness of the device is improved; by using the laminated piezoelectric driver as a driving element, larger load capacity can be realized, and meanwhile, the standardization and mechanization of processing and production are easy to realize, so that the laminated piezoelectric driver is suitable for large-scale production and manufacturing; by using the excitation method, the stable driving effect can be realized only by using a simpler excitation signal, and the ultra-precise motion can be realized by conveniently adjusting the motion step pitch by adjusting the amplitude and the application time of the excitation signal. According to the advantages, the multi-degree-of-freedom piezoelectric motion platform disclosed by the invention improves the degree of freedom of ultra-precise piezoelectric drive, enriches the configuration design of the ultra-precise multi-degree-of-freedom piezoelectric driver, widens the application range of the piezoelectric driver, has important practical significance for the development of ultra-precise multi-degree-of-freedom piezoelectric drive technology and theory, and has wide application prospects in the technical fields of ultra-precise instruments and equipment and the like.

Claims

1. A six-degree-of-freedom piezoelectric motion platform is characterized in that the motion platform comprises a rotor (1), a four-degree-of-freedom driving unit (2), a vertical supporting column (3), a vertical guide rail (4), a transverse guide rail (5), a longitudinal guide rail (6), a two-degree-of-freedom driving unit (7) and a base (8);

the four-degree-of-freedom driving unit (2) comprises an upper side driving foot (2-1), an upper side bidirectional laminated bending type piezoelectric driver (2-2), an insulating layer (2-3), a laminated torsion type piezoelectric driver (2-4), a guide clamping plate (2-5), a laminated linear type piezoelectric driver (2-6) and a middle driving foot (2-7); the two-degree-of-freedom driving unit (7) comprises a supporting splint (7-1), a lower side bidirectional stacked bending piezoelectric driver (7-2) and a lower side driving foot (7-3);

the upper side driving foot (2-1), the upper side bidirectional stacked bending type piezoelectric driver (2-2), the insulating layer (2-3), the stacked torsion type piezoelectric driver (2-4), the guide clamping plate (2-5), the stacked linear type piezoelectric driver (2-6) and the middle driving foot (2-7) are sequentially connected from top to bottom, and the top end of the vertical supporting column (3) supports the middle driving foot (2-7); the vertical supporting column (3), the supporting clamping plate (7-1), the lower side bidirectional stacked bending piezoelectric driver (7-2) and the lower side driving foot (7-3) are sequentially connected from top to bottom; the rotor (1) is tightly pressed on the top surface of the upper side driving foot (2-1), the middle driving foot (2-7) is tightly pressed on the side surface of the vertical supporting column (3), and the lower end of the lower side driving foot (7-3) is tightly pressed on the upper surface of the base (8); the vertical guide rail (4) is arranged along the vertical direction, and the transverse guide rail (5) and the longitudinal guide rail (6) are respectively arranged along the horizontal direction and the depth direction; the supporting clamping plates (7-1) are fixedly connected with the vertical guide rail (4), the guiding clamping plates (2-5) are slidably connected with the vertical guide rail (4), the supporting clamping plates (7-1) are slidably connected with the longitudinal guide rail (6), the longitudinal guide rail (6) is slidably connected with the transverse guide rail (5) and is arranged in a crossed manner, and the transverse guide rail (5) is fixedly connected with the base (8); the base (8) is kept fixed, and the rotor (1) outputs spatial six-degree-of-freedom motion.

2. The six-degree-of-freedom piezoelectric motion platform according to claim 1, wherein the upper driving foot (2-1) is provided with a positioning hole, the positioning hole is matched with the rotor (1), and the rotor (1) is pressed on the top surface of the upper driving foot (2-1) through the positioning hole;

the middle driving feet (2-7) are provided with fixing holes, the fixing holes are matched with the vertical supporting columns (3), and the middle driving feet (2-7) are tightly pressed on the side faces of the vertical supporting columns (3) through the fixing holes.

3. The six-degree-of-freedom piezoelectric motion platform according to claim 1, wherein the upper-side bidirectional stacked bending piezoelectric actuator (2-2) and the lower-side bidirectional stacked bending piezoelectric actuator (7-2) are respectively composed of a plurality of piezoelectric ceramic plates fixedly connected along the axial direction of the four-degree-of-freedom drive unit (2) and the two-degree-of-freedom drive unit (7), each piezoelectric ceramic plate comprises four polarization sections, one of the four polarization sections is a horizontal bending section, and the other one is a depth bending section; the bending deformation of the upper-side bidirectional stacked bending piezoelectric actuator (2-2) and the lower-side bidirectional stacked bending piezoelectric actuator (7-2) under an excitation signal respectively drives the upper-side driving foot (2-1) and the lower-side driving foot (7-3) to do reciprocating swing motion along the horizontal direction and the depth direction.

4. The six-degree-of-freedom piezoelectric motion platform according to claim 1, wherein the stacked linear piezoelectric actuator (2-6) is formed by fixedly connecting a plurality of piezoelectric ceramic plates along the axial direction of the four-degree-of-freedom driving unit (2), and each piezoelectric ceramic plate has only one polarization partition; the telescopic deformation of the laminated linear piezoelectric actuator (2-6) under the excitation signal drives the middle driving foot (2-7) to do reciprocating linear motion along the vertical direction.

5. The six-degree-of-freedom piezoelectric motion platform according to claim 1, wherein the stacked torsional piezoelectric actuator (2-4) is formed by fixedly connecting a plurality of piezoelectric ceramic plates around the axis direction of the four-degree-of-freedom drive unit (2), and each piezoelectric ceramic plate has only one polarization partition; torsional deformation of the laminated torsional piezoelectric driver (2-4) under an excitation signal drives the upper side driving foot (2-1) to do reciprocating rotation motion around the vertical direction.

6. An excitation method of a six-degree-of-freedom piezoelectric motion platform, which is applied to the six-degree-of-freedom piezoelectric motion platform as claimed in any one of claims 1 to 5

The axis direction of the four-degree-of-freedom driving unit (2) is a Z axis, and the clockwise direction of the Z axis is a positive direction;

the depth direction orthogonal to the axial direction of the four-degree-of-freedom driving unit (2) is an X axis, and the clockwise direction of the X axis is a positive direction;

the horizontal direction orthogonal to the axial direction of the four-degree-of-freedom drive unit (2) is a Y axis, the clockwise direction of the Y axis is a positive direction,

the method is characterized in that:

when the mover (1) makes positive direction linear motion along the Y axis, the method comprises the following steps:

s100, pressing the rotor (1) on the top surface of the upper side driving foot (2-1), adjusting the pre-pressure between the upper side driving foot and the upper side driving foot, pressing the middle driving foot (2-7) on the side surface of the vertical supporting column (3), adjusting the pre-pressure between the upper side driving foot and the lower side driving foot, pressing the lower side driving foot (7-3) on the upper surface of the base (8), and adjusting the pre-pressure between the upper side driving foot and the lower side driving foot;

s110, applying an excitation voltage signal with a slowly rising amplitude to a Y-axis direction bending partition in the lower-side bidirectional stacked bending type piezoelectric driver (7-2), driving the lower-side driving foot (7-3) to slowly swing to a limit position along a Y-axis reverse direction through bending deformation of the lower-side bidirectional stacked bending type piezoelectric driver (7-2), and generating linear displacement along a Y-axis positive direction by the two-degree-of-freedom driving unit (7) and the four-degree-of-freedom driving unit (2) under the action of static friction force between the lower-side driving foot (7-3) and the base (8) so as to drive the rotor (1) to generate linear displacement output along the Y-axis positive direction;

s120, applying an excitation voltage signal with a rapidly reduced amplitude to a Y-axis direction bending partition in the lower-side bidirectional stacked bending type piezoelectric driver (7-2), driving the lower-side driving foot (7-3) to rapidly swing to an initial position along the positive direction of a Y axis by bending deformation of the lower-side bidirectional stacked bending type piezoelectric driver (7-2), and keeping the lower-side driving foot (7-3) and the base (8) stationary due to relative sliding under the action of inertia of the two-degree-of-freedom driving unit (7) and the four-degree-of-freedom driving unit (2), so that the mover (1) also keeps stationary;

s130, judging whether the mover (1) moves by a specified displacement, and if so, executing a step S140; otherwise, returning to step S110;

s140, stopping moving the mover (1),

when the mover (1) does reverse linear motion along the Y axis, the method comprises the following steps:

s150, pressing the rotor (1) on the top surface of the upper side driving foot (2-1), adjusting the pre-pressure between the upper side driving foot and the upper side driving foot, pressing the middle driving foot (2-7) on the side surface of the vertical supporting column (3), adjusting the pre-pressure between the upper side driving foot and the lower side driving foot, pressing the lower side driving foot (7-3) on the upper surface of the base (8), and adjusting the pre-pressure between the upper side driving foot and the lower side driving foot;

s160, applying an excitation voltage signal with a slowly-decreasing amplitude to a Y-axis direction bending partition in the lower-side bidirectional stacked bending type piezoelectric driver (7-2), driving the lower-side driving foot (7-3) to slowly swing to a limit position along the Y-axis positive direction through bending deformation of the lower-side bidirectional stacked bending type piezoelectric driver (7-2), and generating linear displacement along the Y-axis reverse direction by the two-degree-of-freedom driving unit (7) and the four-degree-of-freedom driving unit (2) under the action of static friction force between the lower-side driving foot (7-3) and the base (8) so as to drive the rotor (1) to generate linear displacement output along the Y-axis reverse direction;

s170, applying an excitation voltage signal with a rapidly rising amplitude to a Y-axis direction bending partition in the lower bidirectional stacked bending type piezoelectric driver (7-2), driving the lower driving foot (7-3) to rapidly swing to an initial position along a Y-axis direction by bending deformation of the lower bidirectional stacked bending type piezoelectric driver (7-2), and keeping the lower driving foot (7-3) and the base (8) stationary due to relative sliding under the action of inertia of the two-degree-of-freedom driving unit (7) and the four-degree-of-freedom driving unit (2), so that the mover (1) also keeps stationary;

s180, judging whether the mover (1) moves by a specified displacement, and if so, executing a step S190; otherwise, returning to step S160;

s190, stopping moving the mover (1),

when the mover (1) makes positive direction linear motion along the X axis, the method comprises the following steps:

s200, pressing the rotor (1) above the upper side driving foot (2-1), adjusting the pre-pressure between the upper side driving foot and the upper side driving foot, pressing the middle driving foot (2-7) on the side surface of the vertical supporting column (3), adjusting the pre-pressure between the upper side driving foot and the lower side driving foot, pressing the lower side driving foot (7-3) above the base (8), and adjusting the pre-pressure between the upper side driving foot and the lower side driving foot;

s210, applying an excitation voltage signal with a slowly rising amplitude to an X-axis direction bending partition in the lower-side bidirectional stacked bending type piezoelectric driver (7-2), driving the lower-side driving foot (7-3) to slowly swing to a limit position along an X-axis reverse direction through bending deformation of the lower-side bidirectional stacked bending type piezoelectric driver (7-2), and generating linear displacement along the X-axis positive direction by the two-degree-of-freedom driving unit (7) and the four-degree-of-freedom driving unit (2) under the action of static friction force between the lower-side driving foot (7-3) and the base (8) so as to drive the rotor (1) to generate linear displacement output along the X-axis positive direction;

s220, applying an excitation voltage signal with a rapidly reduced amplitude to an X-axis direction bending partition in the lower-side bidirectional stacked bending type piezoelectric driver (7-2), driving the lower-side driving foot (7-3) to rapidly swing to an initial position along the positive direction of an X axis by bending deformation of the lower-side bidirectional stacked bending type piezoelectric driver (7-2), and keeping the lower-side driving foot (7-3) and the base (8) stationary due to relative sliding under the action of inertia of the two-degree-of-freedom driving unit (7) and the four-degree-of-freedom driving unit (2), so that the mover (1) also keeps stationary;

s230, judging whether the mover (1) moves by a specified displacement, and if so, executing the step S240; otherwise, returning to step S210;

s240, stopping moving the mover (1),

when the rotor (1) does reverse linear motion along the X axis, the method comprises the following steps:

s250, pressing the rotor (1) above the upper side driving foot (2-1), adjusting the pre-pressure between the upper side driving foot and the upper side driving foot, pressing the middle driving foot (2-7) on the side surface of the vertical supporting column (3), adjusting the pre-pressure between the upper side driving foot and the lower side driving foot, pressing the lower side driving foot (7-3) above the base (8), and adjusting the pre-pressure between the upper side driving foot and the lower side driving foot;

s260, applying an excitation voltage signal with a slowly-decreasing amplitude to an X-axis direction bending partition in the lower-side bidirectional stacked bending type piezoelectric driver (7-2), driving the lower-side driving foot (7-3) to slowly swing to a limit position along the X-axis positive direction through bending deformation of the lower-side bidirectional stacked bending type piezoelectric driver (7-2), and generating linear displacement along the X-axis reverse direction by the two-degree-of-freedom driving unit (7) and the four-degree-of-freedom driving unit (2) under the action of static friction force between the lower-side driving foot (7-3) and the base (8) so as to drive the rotor (1) to generate linear displacement output along the X-axis reverse direction;

s270, applying an excitation voltage signal with a rapidly rising amplitude to an X-axis direction bending partition in the lower-side bidirectional stacked bending type piezoelectric driver (7-2), driving the lower-side driving foot (7-3) to rapidly swing to an initial position along an X-axis direction by bending deformation of the lower-side bidirectional stacked bending type piezoelectric driver (7-2), and keeping the lower-side driving foot (7-3) and the base (8) stationary due to relative sliding under the action of inertia of the two-degree-of-freedom driving unit (7) and the four-degree-of-freedom driving unit (2), so that the mover (1) also keeps stationary;

s280, judging whether the mover (1) moves by a specified displacement, and if so, executing a step S290; otherwise, returning to step S260;

s290, stopping moving the mover (1),

when the mover (1) makes positive direction linear motion along the Z axis, the method comprises the following steps:

s300, pressing the rotor (1) above the upper side driving foot (2-1), adjusting the pre-pressure between the upper side driving foot and the upper side driving foot, pressing the middle driving foot (2-7) on the side surface of the vertical supporting column (3), adjusting the pre-pressure between the upper side driving foot and the lower side driving foot, pressing the lower side driving foot (7-3) above the base (8), and adjusting the pre-pressure between the upper side driving foot and the lower side driving foot;

s310, applying an excitation voltage signal with a slowly rising amplitude to the stacked linear piezoelectric actuator (2-6), wherein the stacked linear piezoelectric actuator (2-6) is deformed in a stretching manner to drive the middle driving foot (2-7) to slowly move to a limit position along the Z-axis reverse direction, and under the action of static friction force between the middle driving foot (2-7) and the vertical supporting column (3), the four-degree-of-freedom driving unit (2) generates linear displacement along the Z-axis positive direction, so that the rotor (1) is driven to generate linear displacement output along the Z-axis positive direction;

s320, applying an excitation voltage signal with a rapidly-reduced amplitude to the stacked linear piezoelectric actuator (2-6), driving the middle driving foot (2-7) to rapidly move to a limit position along the positive direction of the Z axis by the telescopic deformation of the stacked linear piezoelectric actuator (2-6), and keeping the middle driving foot (2-7) and the vertical supporting column (3) stationary due to relative sliding under the action of inertia of the four-degree-of-freedom driving unit (2), so that the rotor (1) also keeps stationary;

s330, judging whether the mover (1) moves by a specified displacement, and if so, executing a step S340; otherwise, returning to step S310;

s340, stopping moving the mover (1),

when the rotor (1) does reverse direction linear motion along the Z axis, the method comprises the following steps:

s350, pressing the rotor (1) above the upper side driving foot (2-1), adjusting the pre-pressure between the upper side driving foot and the upper side driving foot, pressing the middle driving foot (2-7) on the side face of the vertical supporting column (3), adjusting the pre-pressure between the upper side driving foot and the lower side driving foot, pressing the lower side driving foot (7-3) above the base (8), and adjusting the pre-pressure between the upper side driving foot and the lower side driving foot;

s360, applying an excitation voltage signal with a slowly-decreasing amplitude to the stacked linear piezoelectric actuator (2-6), wherein the stacked linear piezoelectric actuator (2-6) is telescopically deformed to drive the middle driving foot (2-7) to slowly move to an extreme position along the positive direction of the Z axis, and under the action of static friction force between the middle driving foot (2-7) and the vertical supporting column (3), the four-degree-of-freedom driving unit (2) generates linear displacement along the negative direction of the Z axis, so that the rotor (1) is driven to generate linear displacement output along the negative direction of the Z axis;

s370, applying an excitation voltage signal with a rapidly rising amplitude to the stacked linear piezoelectric actuator (2-6), wherein the stacked linear piezoelectric actuator (2-6) is subjected to telescopic deformation to drive the middle driving foot (2-7) to rapidly move to an extreme position along the Z-axis direction, and under the action of inertia of the four-degree-of-freedom driving unit (2), the middle driving foot (2-7) and the vertical supporting column (3) slide relatively to keep still, so that the rotor (1) also keeps still;

s380, judging whether the mover (1) moves by a specified displacement, and if so, executing a step S390; otherwise, returning to step S360;

s390, stopping moving the mover (1),

when the rotor (1) rotates around the Y axis in the positive direction, the method comprises the following steps:

s400, pressing the rotor (1) above the upper side driving foot (2-1), adjusting the pre-pressure between the upper side driving foot and the upper side driving foot, pressing the middle driving foot (2-7) on the side surface of the vertical supporting column (3), adjusting the pre-pressure between the upper side driving foot and the lower side driving foot, pressing the lower side driving foot (7-3) above the base (8), and adjusting the pre-pressure between the upper side driving foot and the lower side driving foot;

s410, applying an excitation voltage signal with a slowly rising amplitude to an X-axis direction bending partition in the upper-side bidirectional stacked bending type piezoelectric driver (2-2), driving the upper-side driving foot (2-1) to slowly swing to a limit position along an X-axis direction by bending deformation of the upper-side bidirectional stacked bending type piezoelectric driver (2-2), and generating rotary displacement output by the rotor (1) around a Y-axis direction under the action of static friction force between the upper-side driving foot (2-1) and the rotor (1);

s420, applying an excitation voltage signal with a rapidly reduced amplitude to an X-axis direction bending partition in the upper-side bidirectional stacked bending type piezoelectric driver (2-2), driving the upper-side driving foot (2-1) to rapidly swing to an initial position along the positive direction of an X axis by bending deformation of the upper-side bidirectional stacked bending type piezoelectric driver (2-2), and enabling the rotor (1) and the upper-side driving foot (2-1) to relatively slide and keep static under the action of inertia of the rotor (1);

s430, judging whether the mover (1) rotates by a specified displacement, and if so, executing a step S440; otherwise, returning to step S410;

s440, stopping rotating the rotor (1),

when the rotor (1) rotates around the Y axis in the opposite direction, the method comprises the following steps:

s450, pressing the rotor (1) above the upper side driving foot (2-1), adjusting the pre-pressure between the upper side driving foot and the upper side driving foot, pressing the middle driving foot (2-7) on the side surface of the vertical supporting column (3), adjusting the pre-pressure between the upper side driving foot and the lower side driving foot, pressing the lower side driving foot (7-3) above the base (8), and adjusting the pre-pressure between the upper side driving foot and the lower side driving foot;

s460, applying an excitation voltage signal with a slowly decreasing amplitude to an X-axis direction bending partition in the upper-side bidirectional stacked bending type piezoelectric driver (2-2), driving the upper-side driving foot (2-1) to slowly swing to a limit position along the positive direction of an X axis by bending deformation of the upper-side bidirectional stacked bending type piezoelectric driver (2-2), and generating rotary displacement output in the opposite direction of the rotor (1) around a Y axis under the action of static friction force between the upper-side driving foot (2-1) and the rotor (1);

s470, applying an excitation voltage signal with a rapidly rising amplitude to an X-axis direction bending partition in the upper-side bidirectional stacked bending type piezoelectric driver (2-2), driving the upper-side driving foot (2-1) to rapidly swing to an initial position along an X-axis direction by bending deformation of the upper-side bidirectional stacked bending type piezoelectric driver (2-2), and enabling the rotor (1) and the upper-side driving foot (2-1) to relatively slide and keep static under the action of inertia of the rotor (1);

s480, judging whether the rotor (1) rotates by appointed displacement, and if so, executing a step S490; otherwise, returning to step S460;

s490, stopping rotating the rotor (1),

when the rotor (1) rotates around the X axis in the positive direction, the method comprises the following steps:

s500, pressing the rotor (1) above the upper side driving foot (2-1), adjusting the pre-pressure between the upper side driving foot and the upper side driving foot, pressing the middle driving foot (2-7) on the side surface of the vertical supporting column (3), adjusting the pre-pressure between the upper side driving foot and the lower side driving foot, pressing the lower side driving foot (7-3) above the base (8), and adjusting the pre-pressure between the upper side driving foot and the lower side driving foot;

s510, applying an excitation voltage signal with a slowly rising amplitude to a Y-axis direction bending partition in the upper bidirectional stacked bending type piezoelectric driver (2-2), driving the upper driving foot (2-1) to slowly swing to a limit position along a Y-axis direction along the bending deformation of the upper bidirectional stacked bending type piezoelectric driver (2-2), and generating rotary displacement output by the rotor (1) around an X-axis positive direction under the action of static friction force between the upper driving foot (2-1) and the rotor (1);

s520, applying an excitation voltage signal with a rapidly reduced amplitude to a Y-axis direction bending partition in the upper-side bidirectional stacked bending type piezoelectric driver (2-2), driving the upper-side driving foot (2-1) to rapidly swing to an initial position along the positive direction of the Y axis by bending deformation of the upper-side bidirectional stacked bending type piezoelectric driver (2-2), and enabling the mover (1) and the upper-side driving foot (2-1) to relatively slide and keep static under the action of inertia of the mover (1);

s530, judging whether the rotor (1) rotates by a specified displacement, and if so, executing a step S540; otherwise, returning to step S510;

s540, stopping rotating the rotor (1),

when the rotor (1) rotates around the X axis in the opposite direction, the method comprises the following steps:

s550, pressing the rotor (1) above the upper side driving foot (2-1), adjusting the pre-pressure between the upper side driving foot and the upper side driving foot, pressing the middle driving foot (2-7) on the side surface of the vertical supporting column (3), adjusting the pre-pressure between the upper side driving foot and the lower side driving foot, pressing the lower side driving foot (7-3) above the base (8), and adjusting the pre-pressure between the upper side driving foot and the lower side driving foot;

s560, applying an excitation voltage signal with a slowly decreasing amplitude to a Y-axis direction bending partition in the upper bidirectional stacked bending type piezoelectric driver (2-2), driving the upper driving foot (2-1) to slowly swing to a limit position along the positive direction of the Y axis by bending deformation of the upper bidirectional stacked bending type piezoelectric driver (2-2), and generating rotary displacement output around the X axis by the rotor (1) in the opposite direction under the action of static friction force between the upper driving foot (2-1) and the rotor (1);

s570, applying an excitation voltage signal with a rapidly rising amplitude to a Y-axis direction bending partition in the upper-side bidirectional stacked bending type piezoelectric driver (2-2), driving the upper-side driving foot (2-1) to rapidly swing to an initial position along the Y-axis direction by bending deformation of the upper-side bidirectional stacked bending type piezoelectric driver (2-2), and enabling the mover (1) and the upper-side driving foot (2-1) to relatively slide and keep static under the action of inertia of the mover (1);

s580, judging whether the mover (1) rotates by a specified displacement, and if so, executing a step S590; otherwise, returning to step S560;

s590, stopping rotating the rotor (1),

when the rotor (1) rotates around the Z axis in the positive direction, the method comprises the following steps:

s600, pressing the rotor (1) above the upper side driving foot (2-1), adjusting the pre-pressure between the upper side driving foot and the upper side driving foot, pressing the middle driving foot (2-7) on the side surface of the vertical supporting column (3), adjusting the pre-pressure between the upper side driving foot and the lower side driving foot, pressing the lower side driving foot (7-3) above the base (8), and adjusting the pre-pressure between the upper side driving foot and the lower side driving foot;

s610, applying an excitation voltage signal with a slowly rising amplitude to the stacked torsional piezoelectric driver (2-4), driving the upper driving foot (2-1) to slowly swing to a limit position around the positive direction of a Z axis by torsional deformation of the excitation voltage signal, and generating rotary displacement output around the positive direction of the Z axis by the rotor (1) under the action of static friction force between the upper driving foot (2-1) and the rotor (1);

s620, applying an excitation voltage signal with a rapidly reduced amplitude to the stacked torsional piezoelectric driver (2-4), wherein the stacked torsional piezoelectric driver (2-4) is torsionally deformed to drive the upper side driving foot (2-1) to rapidly swing to an initial position around a Z axis in an opposite direction, and under the action of inertia of the rotor (1), the rotor (1) and the upper side driving foot (2-1) slide relatively to each other and keep still;

s630, judging whether the mover (1) rotates by a specified displacement, and if so, executing a step S640; otherwise, returning to step S610;

s640, stopping rotating the rotor (1),

when the rotor (1) rotates around the Z axis in the opposite direction, the method comprises the following steps:

s650, pressing the rotor (1) above the upper side driving foot (2-1), adjusting the pre-pressure between the upper side driving foot and the upper side driving foot, pressing the middle driving foot (2-7) on the side surface of the vertical supporting column (3), adjusting the pre-pressure between the upper side driving foot and the lower side driving foot, pressing the lower side driving foot (7-3) above the base (8), and adjusting the pre-pressure between the upper side driving foot and the lower side driving foot;

s660, applying an excitation voltage signal with a slowly-reduced amplitude to the stacked torsional piezoelectric driver (2-4), wherein the stacked torsional piezoelectric driver (2-4) is subjected to torsional deformation to drive the upper driving foot (2-1) to slowly swing to a limit position around the Z axis in the opposite direction, and under the action of static friction force between the upper driving foot (2-1) and the rotor (1), the rotor (1) generates rotary displacement output around the Z axis in the opposite direction;

s670, applying an excitation voltage signal with a rapidly rising amplitude to the stacked torsional piezoelectric driver (2-4), wherein the stacked torsional piezoelectric driver (2-4) is torsionally deformed to drive the upper side driving foot (2-1) to positively and rapidly swing to an initial position around the Z-axis direction, and under the action of inertia of the rotor (1), the rotor (1) and the upper side driving foot (2-1) slide relatively to each other and keep still;

s680, judging whether the rotor (1) rotates by a specified displacement, and if so, executing a step S690; otherwise, returning to step S660;

and S690, stopping rotating the mover (1).