Error compensation of touch trigger probes

This paper discusses a practical approach to the error compensation of touch trigger probes used on coordinate measuring machines (CMMs). A generalised probe error model, an implementation procedure and a case study are presented. The error compensation has been successfully performed with an artificial neural network probe error model, giving a typical error reduction of a factor of 3. The results have shown that the residual probe errors after error correction were approaching the minimum, i.e. limited only by the repeatability of the CMM and probe. The proposed method is fast because most steps in the compensation procedure may be automated. Furthermore, it does not require any expensive equipment. The error correction may be carried out off-line or on-line, which is valuable in both probe error mapping and error simulation (virtual probe).