A Study On The Tool Presetting And Gauging Based On Computer Vision

The tool presetting and measuring system using EO targeting is based on computer vision measurement. It is an instrument inspecting the geometry parameters of tools that integrates applied optics, electronic technology, computer technology and precision measurement technology. It can change these geometry parameters into coordinates in the NCM (Numerical Control Machine) and processing center system. The data base of the tools are formed automatically, and be applied to the high precision tool presetting in the numerical processing.Due to the rapid development of the mechanic processing, the NCM and processing center have been widely used in the full foreign-owned enterprises, the joint venture enterprises and the township enterprises. As an essential part, tool presetting and measuring system is important. Our country's tool presetting and measuring instruments still use optical projection aiming and the measurement is carried our by human sight, which brings much subjective error; at the same time, the measuring is time consuming. Current system can't cater to the high precision, high efficiency mechanic procession. However, the tool presetting and measuring instruments based on computer vision in foreign country have achieved high precision and automation.This subject is developed by Tianjin Machine Optical Instrument Plant and College of Precision Instrument Tianjin University. This paper studies the tool presetting and measuring system based on computer vision and the main contain includes:1.The tool presetting and measuring system using EO targeting based on computer vision is designed, and system construction and performance under lab environment are completed. The work mainly lies in the vision system added to the original system. The vision system includes optical design and mechanical design.2.The camera calibration of the vision system is studied. A new calibration method is proposed based on the calibration theory of measurement and the characteristic of the instrument. The research is focused on the extracting characteristic points with high precision and the primary calibrating experiments are carried out.3.The image processing algorithms needed in the system are studied, including image pre-processing and characteristic parameter extraction.4. The focusing condition evaluation technique using image processing technique is studied, and an evaluation method catering to this system is proposed. 5.The system software is composed and compiled. The primary experiments of the system are performed using the EO targeting system and the grating measuring system.6. The error sources of the tool presetting and measuring system are analyzed.