Measurement, Fitting and Evaluation of Profile Curve of Cams with CMM

It is difficult to establish the work piece coordinate system precisely in measuring cam with CMM. A method is described with which the operator can start to test a cam at any position. The cam profile is scanned only once and all sampling data is used to determine the work piece coordinate system, which make the error objective function minimum. A method to revise the radius of switch probes is also put forward.