Abstract: Error compensation is an important technology to improve the precision of measuring machines. It includes the establishment of error model, error detection and error compensation. According to measuring machines with a sort of special structure, a method of geometric error detection based on laser interferometer is proposed. Mathematical model including 13 original geometric errors is established for error compensation. Each single geometric error including position error, linear motion error, angular motion error and perpendicularity error is detected respectively. Error detection module using this method can also be embedded in measuring software to achieve rapid and repeatable error detections. Results of experiment show that the measurement error of single axis can be reduced from 0.139 9 mm to 0.001 7 mm within the measuring range of 176 mm after error compensation. It is proved that the novel method is an effective way to improve precision of measuring machines.

Key words: Coordinate measuring machines, Error detection, Laser interferometry