Testing the diagonal measuring technique

This paper describes the results of a set of linear displacement accuracy measurements performed on two vertical CNC machining centers. The main scope of the work is to verify or disprove some of the recently claimed limitations of the conventional diagonal measurement method and of the “laser vector” or “sequential diagonal” method. Basically, we tested the effect of a large linear error deliberately introduced into one of the machine tool's axes. It is concluded that the laser vector method has not correctly identified this error and distributed the error into the remaining axes of the machine tool.