The friction and vibration coupling effect of disc brake was investigated using order analysis and wavelet transformation of brake torque variation and brake pressure variation,which were measured from 9 kinds of disc brakes with various disc thickness variation(DTV) and surface runout(SRO) combination under four brake pressure levels on a brake dynamometer test rig.

A mathematical model characterized by disc side face run-out which is as effective as disk thickness variation is established and the physical simulation model is also built on the basis of multi-body system dynamics software ADAMS.

This paper reports a new technology of check and measure, which first use furier transform to acquire information of accurate workpiece surface switch, then transfer the information into electric and input a computer, as a result, we can measure and sort workpieces automativly and quickly.