WO2016197553A1

WO2016197553A1 - Micro-motion platform with adjustable dynamic properties

Info

Publication number: WO2016197553A1
Application number: PCT/CN2015/095409
Authority: WO
Inventors: 陈新; 杨志军; 白有盾; 陈新度; 高健; 贺云波; 陈云; 李成祥
Original assignee: 广东工业大学
Priority date: 2015-06-08
Filing date: 2015-11-24
Publication date: 2016-12-15
Also published as: CN104889950A

Abstract

Disclosed is a micro-motion platform with adjustable dynamic properties, comprising a base (1), elastic sheet groups (201), a micro-motion sub-platform (202), an outer frame (203), a driver, a micro-motion work bench (4), a tension force adjustment mechanism (7), a displacement sensor (6), and a variable damper (8). The elastic sheet groups are provided on two sides of the micro-motion sub-platform, and the lengthwise direction of the elastic sheets is perpendicular to the moving direction of the micro-motion sub-platform. The displacement sensor is provided on an end of the micro-motion sub-platform in a feeding direction. The variable damper is provided inside the placement sensor. The tension force is adjusted to change the rigidity and inherent frequency of a mechanism, and an optimal damping is set at any frequency point by means of the variable damper to satisfy the requirement of a consistent displacement output at any frequency.

Description

Dynamically adjustable micro motion platform

Technical field

The invention relates to a precision motion platform, which can be used for precision operation and macro-micro composite high-speed precision compensation. The invention relates to a dynamic characteristic adjustable micro motion platform.

Background technique

In order to achieve one-dimensional precision movement, accurate and stable feeding mechanism is particularly important because it is closely related to the quality of the product. In addition, due to the small size and high precision of complex optical free-form surfaces, strict requirements are imposed on the micro-feed mechanism. The micro feed system is the basis for processing such products, and is widely used in fast knife servo feed systems, micro motion tables and macro micro composite platforms. Conventional micro-feed devices usually adopt fixed frequency design, which imposes extremely high requirements on material properties and manufacturing errors. Especially when processing different products, the driving frequency usually changes, so that the displacement amplification factor of the fixed-frequency motion platform is inconsistent. Thereby the displacement is amplified and distorted.

Prior Art 1: A fast-tuning fast-blade servo (Invention Patent Application No. 201210055119.X) invented a fast-torque fast-serving servo mechanism that uses a symmetrically arranged flexible hinge to eliminate vertical associated motion . The stiffness adjustment is achieved by the compression spring mounted on the front, which can only be changed by replacing the spring and cannot be continuously adjusted.

Prior Art 2: A frequency-tunable fast-blade servo feed device based on a flexible hinge amplifying mechanism (Invention Application No. 201210250524.7) invents a fast-knife servo mechanism based on a flexible hinge shrapnel, the frequency adjustment principle is through the tension of the elastic piece, Continuous adjustment of frequency and stiffness can be achieved. However, the mechanism uses a displacement amplification method to have a flexible hinge with stress concentration, which affects the service life of the mechanism.

Prior Art 3: A stiffness-frequency adjustable one-dimensional micro-motion platform based on the principle of stress stiffening (Invention Application No.: 201410214605.0) invents a pre-stressed film based on frequency adjustable, which can be used according to different working conditions and driving frequencies. The natural frequency of the micro-motion platform can be adjusted before or during work, and the flexible hinge can be eliminated. The chain amplifying mechanism uses a voice coil motor instead of the piezoelectric ceramic. The non-contact driving and displacement measurement can determine the load condition in real time, and dynamically adjust the frequency of the driving mechanism according to the change of the load condition, so that the dynamic characteristic can be realized. match. Although the above two problems are solved, the mechanism will have a resonance point during the working motion, so that the micro-motion platform can not work at any frequency point, and it is necessary to adjust the avoidance resonance point to define the working frequency range. The invention adds an anti-resonance damping structure, so that the micro-motion platform can work at any frequency point without generating infinite amplitude, and can operate in any frequency band without avoiding the resonance point.

Summary of the invention

The object of the present invention is to provide a dynamically adjustable micro-motion platform that can work at any frequency point, by adjusting the tension and changing the stiffness and natural frequency of the mechanism, and setting the maximum frequency point by the variable damper. Excellent damping to achieve consistent displacement output requirements at any frequency.

To this end, the present invention employs the following technical solutions:

Dynamically adjustable micro-motion platform, including base, shrapnel set, micro-motion sub-platform, outer frame, drive, micro-motion table, tension adjustment mechanism, displacement sensor and variable damper;

Two sides of the micro-motion sub-platform are connected to the inner wall of the outer frame by the elastic piece group, the elastic pieces in the elastic piece group are arranged in parallel, and the longitudinal direction of the elastic piece is perpendicular to the movement of the micro-motion sub-platform direction;

The outer frame is rigidly fixed to the base, and the micro-motion table is rigidly fixed to the micro-motion sub-platform;

The driver includes a stator and a mover, the stator is fixed to the base or the outer frame, and the mover is fixed on the micro-motion sub-platform;

The displacement sensor is disposed at an end of the micro motion sub-platform in a feeding direction;

a groove is formed at a joint between the outer frame and the elastic piece group, so that a thinner inner side of the outer frame is formed. a deformed elastic member, the outer frame being provided with the tension adjusting mechanism for adjusting the degree of deformation of the elastic member;

The variable damper is disposed within the displacement sensor.

Preferably, the variable damper is an extrusion damper or a magnetorheological damper.

Preferably, the variable damper is a shear damper.

Preferably, the displacement sensor is a capacitive sensor or an inductive sensor.

Preferably, the shrapnel group, the micro motion sub-platform and the outer frame are a unitary structure.

Preferably, the tension adjusting mechanism is a bolt passing through the slot, and two ends thereof are respectively connected to both sides of the slot.

Preferably, the tension adjusting mechanism is a piezoelectric ceramic driver passing through the slot, and two ends thereof are respectively connected to both sides of the slot.

The technical principle of the frequency adjustment of the micro-motion platform proposed by the invention is that the natural frequency of the compliant mechanism formed by the pre-stressed film is related to the tension of the pre-stressed film, and the natural frequency of the mechanism is adjusted by adjusting the tension in the pre-stressed film. To meet the requirements of different working conditions, and by providing a variable damper on the displacement sensor, the micro-motion platform can work at any frequency point without adjusting the resonance point; changing the tension of the mechanism by adjusting the tension And the natural frequency, and the optimal damping of any frequency point is set by the variable damper to achieve the consistent displacement output requirement at any frequency.

DRAWINGS

Figure 1 is a front elevational view of an example of the present invention;

Figure 2 is a front elevational view of another example of the present invention;

3 is a schematic view showing the integrated structure of the shrapnel group, the micro motion sub-platform and the outer frame of the one-dimensional micro-motion platform of the present invention.

Wherein, the base 1, the slot 2, the elastic group 201, the micro motion sub-platform 202, the outer frame 203, the stator 301, The mover 302, the jog table 4, the elastic member 5, the displacement sensor 6, the tension adjusting mechanism 7, the variable damper 8, the piezoelectric ceramic piece 701, and the outer frame 203.

detailed description

The technical solution of the present invention will be further described below with reference to the accompanying drawings and specific embodiments.

The dynamic characteristic adjustable micro motion platform comprises a base 1, a spring group 201, a micro motion sub-platform 202, an outer frame 203, a driver, a micro-motion table 4, a tension adjusting mechanism 7, a displacement sensor 6, and a variable damper 8;

The two sides of the micro-motion sub-platform 202 are connected to the inner wall of the outer frame 203 through the elastic group 201. The elastic pieces in the elastic group 201 are arranged in parallel, and the longitudinal direction of the elastic piece is perpendicular to the micro motion. The direction of motion of the sub-platform 202;

The outer frame 203 is rigidly fixed to the base 1, the micro-motion table 4 is rigidly fixed to the micro-motion sub-platform 202;

The driver includes a stator 301 and a mover 302, the stator 301 is fixed to the base 1 or the outer frame 203, and the mover 302 is fixed on the micro-motion sub-platform 202;

The displacement sensor 6 is disposed at an end of the micro motion sub-platform 202 in a feeding direction;

A groove 2 is formed at the joint of the outer frame 203 and the elastic piece group 201, so that a thin deformable elastic member 5 is formed inside the outer frame 203, and the outer frame 203 is provided to adjust the deformation of the elastic member 5. Degree of the tension adjustment mechanism 7;

The variable damper 8 is disposed within the displacement sensor 6.

As shown in FIG. 1 or FIG. 2, the driver drives the micro motion sub-platform 202 and the micro-motion table 4 connected thereto to generate one-dimensional micro-displacement feed. In the production of the shrapnel group 201, the movement of the moving portion in the non-feeding direction is suppressed, and the micro-motion table 4 is mounted with a functional component such as a cutter, and generates a one-dimensional operation under the driving action of the driver. Displacement, complete the corresponding process action, and pass The tension adjusting mechanism 7 changes the degree of tightness of the elastic group 201 to change the natural frequency of the mechanism in the above micro motion, thereby changing the motion characteristics of the fine motion table 4. A displacement sensor 6 is used to detect the one-dimensional micro-displacement of the micro-motion table 4.

A displacement damper 8 is disposed in the displacement sensor 6 for connecting the outer frame 203 and the micro-motion table 4, and the variable damper 8 functions to avoid the infinite frequency when the resonance occurs, so that the micro-motion platform works. In any frequency range, there is no need to adjust to avoid the resonance point, which improves the operating frequency range. The variable damper 8 uses the displacement sensor 6 as a carrier to reduce the independent connection structure of the entire dynamic characteristic adjustable micro-motion platform, and reduces the influence of the micro-motion frequency range due to the increase of the connection structure, thereby ensuring the maximum operating frequency range.

Preferably, the variable damper 8 is an extruded damper or a magnetorheological damper. Extrusion type damping is large, it can be fixed in package, no leakage, and easy to implement.

Preferably, the variable damper 8 is a shear damper. The shear damper has good linearity and is easy to control.

Preferably, the displacement sensor 6 is a capacitive sensor or an inductive sensor. Preferably, the elastic group 201, the micro motion sub-platform 202 and the outer frame 203 are of a unitary structure. As shown in Fig. 3, the whole piece of material is obtained by milling, EDM, etc., which avoids the assembly error of the parts and can improve the movement precision of the platform.

Preferably, the tension adjusting mechanism 7 is a bolt passing through the slot 2, and two ends thereof are respectively connected to both sides of the slot 2. As shown in FIG. 1 , the bolt can manually adjust the displacement in the longitudinal direction, change the deformation degree of the elastic member 5, and then change the elastic tension of the elastic assembly 201 to realize dynamic adjustment of the natural frequency of the structure of the platform.

Preferably, the tension adjusting mechanism 7 is a piezoelectric ceramic driver passing through the slot 2, and two ends thereof are respectively connected to both sides of the slot 2. As shown in FIG. 2, the tension adjusting mechanism 7 includes a bolt And a piezoelectric ceramic sheet 701. The piezoelectric ceramic piece 701 can be displaced in the longitudinal direction of the bolt under the applied voltage, and the deformation degree of the elastic member 5 is changed, thereby changing the tension of the elastic piece of the elastic piece group 201, thereby realizing the inherent structure of the platform. Dynamic adjustment of frequency.

The technical principles of the present invention have been described above in connection with specific embodiments. The descriptions are merely illustrative of the principles of the invention and are not to be construed as limiting the scope of the invention. Based on the explanation herein, those skilled in the art can devise various other embodiments of the present invention without departing from the scope of the invention.

Claims

A dynamic characteristic adjustable micro motion platform, comprising: a base, a shrapnel group, a micro motion sub-platform, an outer frame, a driver, a micro-motion table, a tension adjusting mechanism, a displacement sensor and a variable damper;

Two sides of the micro-motion sub-platform are connected to the inner wall of the outer frame by the elastic piece group, the elastic pieces in the elastic piece group are arranged in parallel, and the longitudinal direction of the elastic piece is perpendicular to the movement of the micro-motion sub-platform direction;

The outer frame is rigidly fixed to the base, and the micro-motion table is rigidly fixed to the micro-motion sub-platform;

The driver includes a stator and a mover, the stator is fixed to the base or the outer frame, and the mover is fixed on the micro-motion sub-platform;

The displacement sensor is disposed at an end of the micro motion sub-platform in a feeding direction;

a groove is formed at a joint between the outer frame and the elastic piece group, so that a thin deformable elastic member is formed inside the outer frame, and the outer frame is provided with the tensioning force for adjusting the deformation degree of the elastic member. Adjustment mechanism

The variable damper is disposed within the displacement sensor.
The dynamic characteristic adjustable micro motion platform according to claim 1, wherein the variable damper is an extruded damper or a magnetorheological damper.
The dynamic characteristic adjustable micro motion platform according to claim 1, wherein the variable damper is an electrorheological or magnetorheological damper.
The dynamic characteristic adjustable micro motion platform according to claim 1, wherein the displacement sensor is a non-contact sensor such as a capacitive sensor, an inductive sensor or a grating scale.
The dynamic characteristic adjustable micro motion platform according to claim 1, wherein the elastic piece group, the micro motion sub-platform and the outer frame are a unitary structure.
The dynamic characteristic adjustable micro motion platform according to claim 1, wherein the tension adjusting mechanism is a bolt passing through the slot, and two ends thereof are respectively connected to two sides of the slot.
The dynamic characteristic adjustable micro motion platform according to claim 1, wherein the tension adjusting mechanism is a piezoelectric ceramic driver passing through the slot, and two ends thereof are respectively connected to both sides of the slot .