3-PRR micro-displacement platform based on symmetrical variable cross-section compliant mechanism

Abstract

The invention discloses a 3-PRR micro-displacement platform based on a symmetrical variable cross-section compliant mechanism, wherein three micro-displacement driving devices are all mounted on a fixed platform; three branch chains connecting a movable platform with the fixed platform are arranged evenly; and in each branch chain, a lever amplification mechanism is connected with the fixed platform through a flexible hinge and a symmetrical trapezoidal compliant mechanism is connected with the lever amplification mechanism through the flexible hinge. One end of the symmetrical folding leaf spring type compliant mechanism is connected with the lever amplification mechanism through the flexible hinge, while the other of the symmetrical folding leaf spring type compliant mechanism is connected with a rigid connecting rod through the flexible hinge; the rigid connecting rod is connected with the movable platform through the flexible hinge; and the movable platform is capable of realizing planar three-freedom degree micro-motion. The symmetrical trapezoidal compliant mechanism of the 3-PRR micro-displacement platform is capable of avoiding incomplete contact of the driving devices when the elastic resistance is as low as possible; as a result, the motion accuracy is improved; and due to the amplification function of the lever amplification mechanism of the 3-PRR micro-displacement platform and the low resistance feature of the symmetrical folding leaf spring type compliant mechanism, large stroke output of the micro-displacement platform can be realized.

Description

technical field [0001] The invention belongs to the technical field of micro-operation in advanced manufacturing. In particular, it relates to a 3-PRR micro-motion platform based on a symmetrical variable-section compliant mechanism. Background technique [0002] With the development of science and technology, micro-positioning technology is urgently needed in the fields of aerospace technology, optics and optoelectronic engineering, biomedical engineering, nanoscience and technology. At present, a combination of piezoelectric elements as the drive and flexible hinges as the transmission is often used. Based on this, various precision micro-motion mechanisms have been developed to achieve sub-micron or even nano-level plane positioning. For example, the Chinese patent literature discloses a two-dimensional micro-motion platform (201010175965.6), a flat three-degree-of-freedom compliant precision positioning platform (201010175965.6), and a two-degree-of-freedom micro-motion...

AI Technical Summary

Problems solved by technology

For example, the Chinese patent literature discloses a two-dimensional micro-motion platform (201010175965.6), a flat three-degree-of-freedom compliant precision positioning platform (201010175965.6), and a two-degree-of-freedom micro-motion platform that can realize micro-motion in the X and Y directions in the plane. But the rotation in the plane cannot be realized, which brings inconvenience to some micro-operations

The existing planar three-degree-of-freedom micro-motion platform is at the motion input end, and the micro-displacement drive device is directly connected to the rigid lever mechanism through a flexible hinge. Since the micro-displacement drive device produces linear motion, it exhibits P-characteristics, which is different from the R-characteristics of flexible hinges. do not match, so the piezoelectric element will have incomplete contact due to the rotation of the lever amplification mechanism, which will inevitably produce a large input coupling error and affect the transmission accuracy; on the other hand, the existing flexible moving pair input and output , the energy is stored too much, which introduces a large elastic resistance and reduces the movement stroke

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