Research On Two Dimensional Motion Precision Measurement System For Ultra-precision Machine Tools

With the rapid development of national defense,aerospace,space telemetry,inertial confinement nuclear fusion and other important fields,higher requirements are put forward for the machining accuracy of ultra-precision machine tools.The machining trajectory of the ultra-precision machine tool is formed by the X-Z axis linkage,which is an important basis for the formation of its machining accuracy.Therefore,the measurement of the twodimensional motion accuracy of the X-Z axis of the ultra-precision machine tool is of great significance for the accuracy performance evaluation and optimization design of the machine tool.In this paper,a measuring technology and system of two-dimensional motion precision for ultra-precision machine tools are studied,which solves the problem that the current measuring instrument is difficult to measure the ultra precision machine tool X-Z axis motion precision synchronously.The main research work of this paper includes:1.A two-dimensional motion precision measurement scheme based on synchronous laser interferometry is proposed.Michelson laser interferometry principle is used to construct the laser interferometry synchronous measurement of two-dimensional motion,which realizes the measurement and analysis of the two-dimensional linkage motion and the precision of planar positioning.2.The overall design and system design of the measurement system are completed.The system architecture and the structure and parameters of the key modules are given,including the polarization interference module,the standard module and the adjustment module.Based on the system precision analysis,the selection of the key components of the system and the overall precision design of the system are completed.3.In view of the influence of the nonlinear error of the photoelectric signal on the measurement accuracy,the quantitative analysis of the DC drift,unequal amplitude and nonorthogonal problems of the signal is completed.On this basis,a real-time compensation method for the nonlinear error of the signal is proposed,and the feasibility and accuracy of the method are verified.4.The test equipment of the measuring system is established,and the performance test experiment is completed,the accuracy and stability of the measuring system are verified.