Configuration Optimization of Laser Tracker Stations for Large-scale Components in Non-uniform Temperature Field Using Monte-carlo Method☆

Abstract The laser trackers play an important role in fabrication and assembly of aircraft, spacecraft and other large-scale products, and optimization of laser tracker configuration station is one of the core issues. When laser trackers are used on the shop floor, environment factors, especially non-uniform temperature can induce considerable measurement uncertainty. Aiming to reduce measurement uncertainty of laser tracker, optimization of laser tracker configuration station for large-scale components in non-uniform temperature field using the Monte-Carlo method is proposed. Firstly, an improved mathematical model for measurement uncertainty of laser tracker is established. This mathematical model is more applicable to measurement uncertainty evaluation of laser tracker because it takes main measurement uncertainty sources (mechanism system and non-uniform temperature) into account. Secondly, the Monte-Carlo method is used to evaluate measurement uncertainties of laser tracker in different configuration stations. Based on the measurement mathematical model, a serial of simulation data can be generated to evaluate the uncertainty of measurement task. Through iterations, the optimal configuration station of laser tracker, in which measurement uncertainty is minimal, can be obtained. Finally, an example of measurement scenario about measuring the inspection jig of an aircraft door demonstrates that the proposed method is feasible and effective. The proposed approach to identify the optimal position of laser tracker is intuitionistic and efficient.