Optimization for Calibration Model of Workspace Measurement Positioning System (wMPS) Based on Distance Constraint
A workspace measurement positioning system (wMPS), with its application range gradually expanded, is a three-dimensional (3-D) space real-time dynamic parallel measurement system based on optoelectronic scanning. To realize its application in the engineering measurement field, problems of conversion between the system and existing measurement datum and external parameter calibration of the system should be solved. Existing control points used and by introducing coordinate constraint and rigid constraint with space angular measurement model combined, the method of fourpoint centring rod receiving device with circular levelling bubbles was proposed in this paper to complete external parameter calibration of the system, and then optimal equation of penalty function L-M algorithm with distance constraint was given to realize application of local positioning system in engineering measurement field. Experiment indicated that after dualstation system completed through this method was calibrated with existing control pointed, its precision met engineering measurement requirements, so it could be applied to engineering measurement field.
Keywords: Laser, workspace measurement positioning system (wMPS), coordinate constraint, control points; L-M algorithm