Objective:In order to realize automatic and high- efficient measurement for parts

Laser Guiding Measurement Robot (LGMR) system is established and the robot is made. Eccentricity error of rotating axis for optical trakcer and angle error of the joint line are investigated. Method:First

LGMR tehcnology and its working princile based on the measurement method “laser beam moving

SMR (Spherical Mounted Retroreflector) tracking” are presented . The experimental robot is made according to the technology and the ideal geometry relationship of LGMR is provided. Then the mathematical models of main geometric errors are firstly presented

including eccentricity error of rotating axis for optical tracker and angle error between nominal line to practical line from the middle of two wheels to SMR. Result: an experiment is carried out to both to prove the correctness of the method and to find out the angle error between nominal line to practical line from the middle of two wheels to SMR be 0.13 mm on the x-axis direction

which uses CMM and laser guiding measurement robot system. Conclusion:The results show that two errors have a greater effect on the measurement accuracy

and can be reduced or eliminated by improving machining accuracy of main parts and error compensation. The paper plays an important role in designing and completing motion feedback control system of laser guiding measurement robot.