Some researches have been done on the main aspects of error compensation which include error analysis of MBS, the modeling of geometric error of CNC gear measure machine, the measurements of gear geometric error, radius offset of instrument head and error compensation by soft-ware in this paper and the works have also been verified through a series of simulation tests.

A Method of 3-Dimensional Probe-radius Compensation in Freeform Surface CMM Measurement;

At the same time,a hemispheric probe of unique structure is proposed for measurement and radius compensation,which is crucial to VCCM and simplifies greatly the measurement and data processing.

Based on analyses the existing methods of the probe radius compensation,a new algorithm named "4-point build a sphere" is proposed.

The research actuality of key technologies relevant to the complex surface measurements such as data acquiring, curved surface reconstruction, probe radius compensation and deviation assessment is summarized.

Measuring technologies with 3D-coordinates measuring machines (CMM) for reverse engineering were investigated to implement the distribution of sampling points of curves and surfaces, probe parameters setting and probe radius compensation, to plan reasonable measuring paths.