Three-dimensional metrology frame for precision applications

A three-dimensional, non-contacting metrology frame providing position and orientation information for an object in space is presented. The metrology system uses information from three position sensors and three laser beams t o produce a six degree-of-freedom spatial representation of the object bein g measured. The metrology system shows potential for decreasing the cost an d complexity of small motion, three-dimensional measuring devices while inc reasing range of motion. Potential applications include the metrology of sc anning probe microscopy stages, optical fabrication devices, and magnetic r ead/write head research platforms. Several significant points are presented in this article. In order of importance, they are 1) description of the ne w system; 2) derivation of the forward and inverse kinematics of the new me trology frame; and 3) development of a methodology for determining the erro r budget of the system (standard approaches are not possible for this confi guration). The feasibility of the approach is shown with the development of an example error budget for a fully general configuration. (C) 1999 Elsevi er Science Inc. All rights reserved.