Abstract
Coordinate measuring machines (CMMs) have been widely used in various fields of science and engineering. Although CMMs are precise instruments, they have a lot of inherent geometrical errors and probing errors. Due to this reason estimation of measurement uncertainty is extremely difficult for CMM measurements. Virtual coordinate measuring machine (VCMM) which has been developed by Physikalisch-Thchinische Bundesanstalt (German national physical institute) is one of the methods of estimating the uncertainty of measurements using CMMs. The geometrical errors are required as an input to the VCMM software, and usually measured using a ball-plate. The measurement of the geometrical errors is a complicate task and carried out less than once a year. In this paper, we propose a new CMM calibration scheme using the Internet, which we call e-trace. National metrology institutes or calibration service providers remote-control users' CMMs and measure the geometrical errors through the Internet. The users, therefore, do not have to have ball-plates or to learn the method of the measurement of geometrical errors. The concept of e-trace and some fundamental experiments will be described.
