考虑多环节间隙非线性的电动舵机多学科耦合动力学建模

Due to uncertainties in the design and assembly process, nonlinear factors such as clearances often exist in multiple sectors of the aerospace electro-mechanical actuator transmission system, significantly affecting the working quality of the electro-mechanical actuator. Therefore, it is essential to accurately establish a nonlinear dynamic model for the electro-mechanical actuator accurately. Moreover, electro-mechanical actuators involve multiple disciplines such as servo control, motor transmission, reduction mechanism, structural elasticity, etc., making the modeling process highly challenging. The research object in this paper is a standard ball screw-type electromechanical actuator. Considering the elastic stiffness of actuator transmission components and the nonlinearity of clearances at gear pairs, supporting bearings, and fork pairs, the motor dynamics and servo controllers are finely modeled. The electro-mechanical actuator system is represented by a high-fidelity multidisciplinary dynamic model that can account for nonlinearities in different sector clearances. Furthermore, simulation analysis of the electromechanical actuator system performance is conducted. The simulation results are compared with ground vibration test results of the actuator-rudder system. The results indicate that the multidisciplinary coupled dynamic model of the electro-mechanical actuator established in this paper can reflect the influence and degree of influence of the clearances in different parts of the mechanism. The simulation and experimental results are in good agreement, with a maximum error of less than 10%. This research lays the foundation for the digital twin study of complex aerospace electric servo systems.