Random attitude measurement method for kinematic calibration of five-shaft hybrid machine tool

Abstract

The invention relates to a random attitude measurement method for kinematic calibration of a five-shaft hybrid machine tool. The five-shaft hybrid machine tool includes a machine tool work bench and a parallel main shaft head. The parallel main shaft head has two rotation freedom degrees and a translation freedom degree; and relative motion with two translation freedom degrees can be formed by the parallel main shaft and the machine tool work bench. The measurement method is characterized in that a dial indicator is fixed on a moving platform of the parallel main shaft head of the hybrid machine tool along a normal direction; gauge blocks are fixed on the machine tool work bench. The dial indicator extends a delta 1 range by controlling motion of the five-shaft hybrid machine tool, wherein the corresponding displacement of the dial indicator at directions of the three machine tool translation shafts including an X shaft, a Y shaft, and a Z shaft are delta x, delta y, and delta z; inverse cosine functions of ratios of the delta x, delta y, and delta z to a delta 1 are equal to included angles alpha, beta, and gamma between the normal direction of the moving platform and the X shaft, the Y shaft, and the Z shaft respectively, thereby obtaining a moving platform attitude. According to the measurement method, only the dial indicator and the gauge blocks are needed; and the method has characteristics of simple operation, and high economy and practicability. And a random attitude measurement value with high precision can be obtained.

Description

technical field [0001] The invention relates to a measuring method based on a contact measuring instrument, more precisely, relates to an arbitrary attitude measuring method used for kinematic calibration of a five-axis hybrid machine tool, and belongs to the technical field of space angle measurement. Background technique [0002] Five-axis hybrid machine tool is an important equipment for processing large aerospace thin-walled parts. Among them, the five-axis hybrid machine tool composed of two-degree-of-freedom serial mechanism and three-degree-of-freedom parallel mechanism has unique advantages and has attracted more and more attention. The five-axis hybrid machine tool is a CNC machine tool that combines the characteristics of large working space of the series mechanism and large acceleration and high rigidity of the parallel mechanism, aiming at high-speed and high-precision machining. The Ecospeed hybrid machine tool developed by German DST company and the Space-5H hy...

AI Technical Summary

Problems solved by technology

[0005] However, in the current kinematics calibration of five-axis hybrid machine tools, position measurement is relatively easy to implement, while attitude measurement is more difficult. The reasons are: 1. Use special instruments such as inclinometers, laser trackers, ballbars, and CCDs to measure Although the attitude of the five-axis hybrid machine tool can measure any attitude, its cost is high, and the general measurement accuracy cannot reach the measurement accuracy required for kinematic calibration; Often the measurement steps are cumbersome and the measurement attitude is limited

At present, attitude measurement mainly faces three major problems: first, the cost of measurement is high; second, the measured attitude is limited by the measurement method, that is, the attitude of the entire workspace cannot be effectively measured; third, attitude measurement is cumbersome and time-consuming

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