The Specialized Calibration Technology Research Of Coaxiality Measurement Device About Big Distance Of Porous Parts

Nowadays,the measurement of long aixs and plug gauge was adopted to detect the coaxiality for long and porous parts,and the measurement results was hard to guarantee the percent of parts pass.However,the problems of coaxiality and diameter for long and porous parts were solved by the long and porous parts coaiality detecting device,overcoming the low efficiency、low precison and low reliability of long axis and plug gauge and realizing the automation of geometric quantity detection process for porous parts.Considering the wide engineering application prospects of long and porous parts coaxility detecting device,the corresponding calibration device was necessary to guarantee the precison of measurement value.Aiming at the precision calibration problems of coaxiality measurement device about big distance of porous parts,the coaxiality error sources, measurement methods for porous parts,error calculation models were researched,the principle and constitution of calibration system were summarized,the calibration system structure and control model had been established.A special coaxiality method was proposed to provide a group of standard porous parts simulator whose coaxiality is known.The actual value acquired by the coaxiality measurement device was compared with the standard value to get the measurement error. This calibration system consisted of three-dimensional precision motion platform and ring gauge,the grating ruler was selected to measure the displacement,and TMS320F2812 was selected as the system control chip,the minimal region algorithm based on the least square principle was proposed to calculate the coaxiality of standard porous parts.The results indicate that this system resolution can reach 1um and the uncertainty can reach 5.8um,and it can effectively calibrate the precision error of coaxiality measurement device.