Laser Tracker Based Measurement Of Aircraft’s Position And Attitude

In this paper, research on the measurement method of aircraft’s position and attitude is conducted at the background of aircraft assembly. The measurement systems are compared, and the measurement scheme is proposed according to the characteristics of the measuring system selected. The method to solve the position and attitude of the aircraft is raised and its error is analyzed. The error source of the aircraft’s position and attitude is analyzed and the error model of the aircraft’s position and attitude is put forward. Finally, the measurement method of the aircraft’s position and attitude is tested and verified.Firstly, position and attitude of aircraft is defined according to the conversion between the coordinate systems, and the measurement principle of aircraft’s position and attitude is studied. Several digital measurement systems for large space are compared and the laser tracker measurement system is selected. The measurement scheme of aircraft’s position and attitude measurement based on laser tracker program is proposed.Then, the solving methods of aircraft’s position and attitude is studied. The calculation model of the initial value for aircraft’s position and attitude is derived with the least square method. A solving method of aircraft’s position and attitude based on the conjugate gradient method is proposed and its error is analyzed.Thereafter, this paper carries out the research of the error of aircraft’s position and attitude. The error source is analyzed based on the calculation model. The error propagation formula is derived with the help of the Taylor expansions of the equation between the aircraft coordinate system and the global coordinate system. The error model of the aircraft’s position and attitude is established.Finally, the measurement method of the aircraft’s position and attitude based on the laser tracker is verified. The experiment shows that the measurement error of the turntable’s attitude angle is less than 0.01 degree, and the matching error of coordinate at the turntable coordinate system and the global coordinate system is less than 0.5mm which satisfies the desired accuracy. The error analysis shows that the measurement error of the turntable’s attitude angle mainly comes from the manufacturing error.