A Study of On-Machine Measurement with the Compensation of Probe Sensitivity in a Machine Tool
Yoshio Mizugaki, Teruyuki Asao, Masafumi Sakamoto,
Production Engineering Lab., Department of Mechanical Engineering, Kyushu Institute of Technology, Japan, 1-1, Sensui-cho, Tobata-ku, Kita Kyushu, Fukuoka, 804 Japan
This paper presents a new method of the compensation of sensitivity of a touch probe in a machine tool. In this study the sensitivity is defined as measurement error in each probing direction. In the detection of measurement errors, a reference ball used in Coordinate Measuring Machines is adopted as the pseudo-datum. After measuring it in various probing directions, each measurement error of lobbing is modelled by means of a spline interpolation. Thus, the sensitivity model is represented in form of Coons patch whose parameters at the angles of probing direction. The effect of probing approach speed on measurement error has also been examined. The finishing process after the on-machine in-process measurement is conducted in order to evaluate the utility of the sensitivity model. Through the measurement of finished surfaces, the utility of finishing process and the validity of the sensitivity model are confirmed.