In addition to the four geometric errors of positioning error, straightness error, angular motion error, and perpendicularity error, the CMM​ also has four geometric errors due to force deformation, thermal deformation, measurement system, probe system, control system, data recording and processing.

The CMM is guided by air bearings, so that there is no friction and wear between the guide rails, and long-term performance uniformity can be maintained. The high-pressure gas enters between the working surface and the guide surface through the small air holes in the air bearing, forming a uniform air gap. The normal working air gap of the air bearing is between 3 and 10 μm.