Three-DOF (degrees of freedom) precision micro-shift probe based on electrohydraulic amplification and three-DOF precision micro-shift measuring method based on electrohydraulic amplification

Abstract

The invention discloses a three-DOF (degrees of freedom) precision micro-shift probe based on electrohydraulic amplification, comprising a base, a probe tip and three measuring arms. Each measuring arm includes an electrohydraulic amplifier and a connection rod, a cavity is arranged in the electrohydraulic amplifier and includes a small diameter segment, a variable diameter segment and a large diameter segment arranged in sequence, the small diameter segment is arranged on the electrohydraulic amplifier and fixedly connected to one end of the base, the small diameter segment is provided with piezoelectric ceramic, the cross section of the variable diameter segment decreases gradually from bottom to top, a piston moves axially along the large diameter segment, the cavity is filled with a liquid between the piston and the piezoelectric ceramic, and two ends of the connection rod are provided with flexible spherical hinges respectively in order to connect the piston of the corresponding electrohydraulic amplifier and the probe tip. A measuring method comprises allowing a rigid probe tip to act on the surface of a test object through the three-DOF structure, converting spatial shift ofthe test object into three groups of voltage signals through three groups of connection rods and electrohydraulic amplifiers, decoupling the three groups of voltage signals, and analyzing and calculating actual shift of the test object.

Description

technical field [0001] The invention belongs to the field of precision measurement, in particular to a three-degree-of-freedom precision micro-displacement probe based on electro-hydraulic amplification and a measurement method thereof. Background technique [0002] With the development of modern industrial technology and the continuous advancement of science and technology, mechanical equipment is developing in the direction of large-scale, high-speed, and precise, and the demand for small displacement detection in the operation of mechanical equipment is also increasing. However, methods such as inertial sensing units, pull wire sensors, and magnetostrictive displacement sensors are generally used in displacement detection for displacement detection. However, due to the limitations of the size of the sensor itself and the installation method, it is quite difficult to detect the displacement of small objects; The needle type can realize displacement detection of a feature p...

AI Technical Summary

Problems solved by technology

However, methods such as inertial sensing units, pull wire sensors, and magnetostrictive displacement sensors are generally used in displacement detection for displacement detection. However, due to the limitations of the size of the sensor itself and the installation method, it is quite difficult to detect the displacement of small objects; The needle type can realize displacement detection of a feature point. In order to realize multi-directional displacement detection, multiple articulated arms need to be connected in series. After adopting the series structure, the system rigidity is relatively poor, and the overall performance is that the system accuracy is difficult to control. Inhomogeneity in accuracy exhibited in space

Parallel mechanism has unique advantages such as good rigidity, light moment of inertia, and natural error averaging effect. It has been very maturely applied in parallel robots, parallel machine tools and MEMS actuators, but in the field of displacement measurement, parallel mechanism is not very good. good application

At the same time, in the micro-displacement amplification structure, flexible rod groups are usually used in series for displacement amplification, but due to the complexity of the flexible rod group series amplification structure, and due to the flexible properties of the flexible member itself, the accumulation makes its rigidity poor and insensitive to small displacements. Difficult to capture precisely

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