Precision Positioning System Based On Aerostatic Linear Guide Drived By Ultrasonic Motor

With the development of the modern science and technology, the research of photoelectron, micro-electro-mechanical, bioengineering and nano materials in the field of micro is more and more deep, the demands of precision positioning is now into the micro and nano era. Precision positioning technology is widely used in precision instruments, machinery and machine tools, IC manufacturing technology, computer peripheral equipment, etc.Its characteristics are high accuracy and resolution, the size varies from tiny to large, it has a great variety, mostly need to integrate with many high-performance and high-quality mechanical parts, also with high resolution detection components, it has automation requirement, so it is difficult to generate and needs big investment. The research of precision positioning system based on aerostatic linear guide drived by ultrasonic motor will promote the further development of multi-discipline, it is of great scientific significance and extensive practical value.This paper, combined with the National High Technology Research and Development Program( "863" Program) of China " high-resolution tomography and detection system on fine structure of cross-scale ", studies precision positioning system based on aerostatic linear guide drived by ultrasonic motor. The positioning scheme and overall structure is designed according to the characteristics and requirements of precision positioning system.In order to realize precision positioning in a with wide-range, aprecision positioning system with good repeatability is developed combining ultrasonic motor, aerostatic guideway with pipeline channeling off used air, double grating device and servo control system. The system can realize the function of high precision positioning, and can display the position of the linear guideway in real time. This system uses ultrasonic motor as the drive device, it has no electromagnetic interference, which can drive the linear guideway without travel restrictions, it has the characteristics of high frequency, and dosen’t have low speed crawl, so the ultrasonic motor can improve the stability of the movement of aerostatic linear guide, as to improve the precision of the positioning system. Using aerostatic guideway with pipeline channeling off used air overcome the residual air influence on the precision positioning system. The system uses the double grating device as the position feedback device, the lower precision grating ruler works as position feedback for motion control, the higher precision grating ruler can be used to measure, so that not only the speed of motion control is improved, but also the accuracy of the measurement is higer, the requirements of the system can be better meeted. PID control technology is applied in the process of positioning, the system has fast and smooth response characteristics by adjusting PID parameters of the servo controller. At the same time, the control software, based on VC++6.0, is designed to realize precision positioning.