Accurate Transfer Function Identification Based on a Dynamic Mathematical Model of Digital Steering System

During the launch process of an electromagnetic shell, all parts of the steering system need to bear the impact of the high-intensity instantaneous acceleration and real-time change of the system operation parameters. These problems affect the dynamic characteristics of an actuator system against overload and accurate position tracking. In this study, the dynamic mathematical model of a digital steering gear servo control system is established. A segmented error PID control method is proposed to analyze the dynamic characteristics of the actuator. The results help verify the accuracy of segmented error PID control method for analyzing the dynamic characteristics of the system. Subsequently, an electric actuator test system is designed and the step response and frequency characteristics of the actuator system are tested. Based on the experiment/least square method, the transfer function of the servo system is identified and compared with that of the simulation model; further, the accuracy of the identified transfer function is verified. This paper presents a novel method for accurately predicting the transfer function of the actuator system.