Ultra-light and ultra-accurate portable coordinate measurement machine with enhanced precision joints

摘要

A portable coordinate measurement machine (CMM) includes an articulated arm including rotary joints. At least one of the rotary joints includes bearings; a shaft that engages an inner diameter of the bearings, the shaft configured to rotate about an axis of rotation of the bearings; a housing having at least one port that engages an outer diameter of at least one of the bearings; and at least one transducer configured to output an angle signal corresponding to an angle of rotation of the shaft relative to the housing about the axis of rotation. The shaft has two ends, the two ends may be concentric to within one tenth of thousands of an inch (0.0001″), or the at least one port of the housing may have no portion whose diameter is narrower than the outer diameter of the first bearing or the second bearing.