Laser Tracker Position Optimization

Abstract

This article presents a laser tracker position optimization code based on the tracker uncertainty model developed by the National Physical Laboratory (NPL). The code is able to find the optimal tracker positions for generic measurements involving one or a network of many trackers, and an arbitrary set of targets. The optimization is performed using pattern search or optionally, genetic algorithm (GA) or particle swarm optimization (PSO). Different objective function weightings for the uncertainties of individual points, distance uncertainties between point pairs, and the angular uncertainties between three points can be defined. Constraints for tracker position limits and minimum measurement distances have also been implemented. Furthermore, position optimization taking into account of lines-of-sight (LOS) within complex CAD geometry have also been demonstrated. The code is simple to use and can be a valuable measurement planning tool. uncertainties of tracker networks. These models allow post-measurement bundle adjustment and assessment of uncertainties. They also allow the simulation and planning of measurement tasks, in the case of SpatialAnalyzer within a 3D CAD environment. The ability to plan laser tracker measurements has the benefit of reducing measurement uncertainties and time, and leads to an obvious question: What is the optimal measurement plan for a particular task? In this article we attempt to start answering this question by introducing a code that minimizes m