Modeling and simulation of the assembly accuracy of aero-engine rotors in the docking processes using a specially designed novel multi-DOF NC motion platform

Abstract

The assembly accuracy of aero-engine rotor parts is strictly required in the docking processes. The application of a multi-degrees-of-freedom (multi-DOF) numerical control (NC) motion platform could potentially replace traditional manual docking operations for its better performance. A key issue is ensuring the assembly accuracy qualified by using the new mechanism. In this paper, a systematic study is carried out on modeling and simulation of the docking assembly accuracy of aero-engine rotors using a specially designed novel multi-DOF NC motion platform. A simulation algorithm based on the Monte Carlo method is proposed, to simulate large quantities of rotor assemblies under different docking conditions. To construct the algorithm, new general models are proposed to indicate the geometric errors and assembly accuracy in typical rotor parts. A motion error model of a novel multi-DOF NC motion platform is established using the differential transformation method. Then, simulation results are analyzed to guide the precision design of the six driving systems in the motion platform, and verified by experiments. The results show that the optimized precision setting of the motion platform achieves the qualified rates of assembly accuracy exceeding 92.0% under most docking conditions. For the six items representing assembly accuracy, the deviation rates between the simulation and experimental results are less than 23.0%. The modeling and simulation study has referential significance for both theory and practice.