Optimization of assembly accuracy control in aircraft manufacturing and accuracy improvement strategies by finite element analysis methods

Abstract

The parallel mechanism has the advantages of good posturing performance, fast response, high precision and strong load carrying capacity, and its application in flexible positioning of machine assembly has shown significant technical advantages in recent years. This paper proposes a 3-UPS parallel configuration based on the aircraft assembly posturing and positioning mechanism, which can realize the 6-degree-of-freedom posturing and positioning of the aircraft component assembly. At the same time, in order to improve the precision of vehicle assembly, the influence of the error gap between the hinges of each motion vice on the attitude of the vehicle assembly attitude adjustment and positioning mechanism is analyzed, and the effective rod length model of the 3-UPS parallel connection mechanism is established accordingly. Further, based on the assembly level, order and constraint information, the assembly deviation transfer model of the 3-UPS attitude positioning mechanism was obtained. Finally, the optimization effect of calibration and compensation of geometric error is analyzed by finite element. The results show that the maximum position error of the vehicle assembly is reduced from 0.371mm to 0.037mm after optimization and compensation, and the motion accuracy of the mechanism is improved by one order of magnitude compared with that before compensation. The maximum attitude error is reduced from the original rad to . It is verified that the method of this paper is effective for reducing the positional error of the moving platform of the parallel mechanism and improving the assembly accuracy of the vehicle assembly.