Research On The Key Technologies Of WMPS Dynamic Position And Pose Measurement

The rapid development of high-end equipment manufacturing industry such as aerospace has urgent demands for large scale precision measurement technology.Traditional static measurement methods fail to meet the requirements of highly automatic and intelligent production mode.It is a crucial problem to develop high-precision,real-time and robust dynamic six-degree-of-freedom synchronization measurement methods.Workspace Measuring and Positioning System(wMPS)has distributed network structure and is capable of measuring the coordinates basing on the principle of photoelectric scanning and multi-angle intersection.It has the advantages of high precision,parallel measurements for multi-target and good network scalability.However,limited to the principle of multi-angle intersection,the relative movement between receivers and transmitters will lead to asynchronous angle measurements and intersection error,which has negative effects on dynamic measurement accuracy.In this paper we analyzed the conflicts between the technical state of wMPS dynamic measurement and common application requirements,and systematically focused our research on four aspects of wMPS dynamic position and pose measurement:the position and pose measurement model,the generation mechanism of dynamic position and pose error,dynamic position and pose error modeling and analysis,and dynamic accuracy control.The research content includes:1.Aiming at the limits for spatial intersection from the traditional method based on coordinate transformation,we proposed a position and pose measurement model based on front-back angle intersection and showed its advantages in accuracy and applicability.Then we explained the dynamic error generation mechanism in the view of scanning angle measurement,constructed the kinematic scanning angle error model,and analyzed the propagation characteristics of receiver movement,scanning angle error and dynamic position and pose error.2.We proposed the error reduction methods on the software and hardware level based on transmitter rotation performance optimization,measuring filed layout optimization,and position and pose calculation process optimization.We also proposed dynamic error compensation methods based on aided movement information.Thus we detailedly analyzed the accuracy control strategies both in the perspectives of sigle system and aided exterior system.3.We presented the inertial-information-aided method for wMPS dynamic position and pose measurement.We developed solutions for spatial coordinate system integerated calibration and time synchronization,analyzed the time-domain modeling method for wMPS dynamic error and constructed the decision-level data fusion model for IMU and wMPS,which benefited to improve both the dynamic measurement accuracy and frequency.4.We proposed the data-level fusion model based on raw scanning angle measurement of wMPS.To deal with the nonlinear measurement model of wMPS,an iterative filter method and fusion algorithm optimization method were introduced to improve the model stability and instantaneity.Thus,we further enhanced the dynamic measurement performance and applicability in complex environment.Our system was applied in the infield experiments of space probes and helped to solve the problem of dynamic and accurate measurements of position and pose in large space.