Modeling and Experimental Study on the Dynamic Stiffness of an Electromechanical Actuator

Abstract

An increasing number of applications of the electromechanical actuator in the control actuation system of flight vehicles have recently required an accurate electromechanical actuator model. In this study, the modeling method of the dynamic stiffness of the electromechanical actuator, including nonlinear parameter estimation, is presented. The validation of a dynamic stiffness model is executed through comparison of experimental and simulation results, indicating good consistency of experimental data with the simulation results. Additionally, in order to analyze the effects of nonlinear parameters of the electromechanical actuator on the dynamic stiffness, pragmatic experimental approaches are explained and performed using the electromechanical actuator hardware and a hydraulic excitation system that is used for inputting an aerodynamic load into the electromechanical actuator. Experimental and simulation results showed that the dynamic stiffness changed, depending on the magnitude of the external load and the preload. The dynamic stiffness of the electromechanical actuator also increased under conditions of small free play and large static stiffness values of the electromechanical actuator components