Laser tracker system (LTS) is one of the latest portable three dimensional large size coordinate measuring machines (CMMs). It measures 3D coordinates with laser beam by following a spherical mounted retro-reflector (SMR) with the advantages of broad range

high speed and high accuracy. However

the current inspecting task of LTS is performed manually to move SMR along the different position on the surface of a given part and measured with complex course

low efficiency and the trial-and-error approach

which cause the deformation of measured part and seriously affect the measurement accuracy. In order to perform LTS more efficiently and automatically

a new laser tracking measurement theory of “laser beam moving and SMR tracking” is proposed. The laser guided measurement robot (LGMR) technology is studied and a miniature wheel-armed LGMR system is developed based on this theory which can move on the horizontal and vertical surface of measured part. The LGMR system combines the merits of wheeled mechanism

armed mechanism and vacuum-sorbs mechanism

and possesses many advantages

such as less weight

small volume

simplicity structure and quickly response. LGMR can changes the measuring modes according different characteristics of parts

it moves on the horizontal surface with high speed and remote distance using wheeled system

and climbs flexibly on the smooth inclined surfaces using crawling armed system. The moving characters of LGMR are analyzed in detail. The Faro SI laser tracker and Hexagon Globle9128 coordinate measuring machine (CMM) are used to test the performance of LGMR

the experimental results show that the LGMR can track laser beam automatically and effectively measure on the surfaces of given part.