Analysis of First-Order and Second-Order Modeling of the FESTO EMMT-AS-80-S-LS-RM DC Servo Motor Using MATLAB/Simulink

Abstract

This study focuses on the mathematical modeling and simulation of the FESTO DC servo motor, type EMMT-AS-80-S-LS-RM, using both first-order and second-order approaches. The main objective is to evaluate the accuracy and effectiveness of each model in representing the motor’s dynamics, both in open-loop and closed-loop systems. The modeling process is based on the motor’s technical parameters obtained from its datasheet, utilizing linear differential equations that are simplified into transfer functions. The first-order model is represented as a linear system without considering full inertia, while the second-order model incorporates the complete electromechanical dynamics of the system. Simulations were implemented in the MATLAB/Simulink environment, with a 24 V step input signal. The simulation results indicate that both the first-order and second-order models yield a steady-state angular velocity of 6.957 rad/s. However, theoretical calculations show a value of 314.16 rad/s, resulting in a deviation or error of 44.15%. This discrepancy suggests a unit mismatch and highlights the need for parameter validation and model calibration. Despite this, the second-order model demonstrates more realistic dynamic characteristics compared to the first-order model, especially in transient response. Therefore, the second-order model is recommended for precision control applications, while the first-order model is more suitable for initial design stages and educational purposes. This study also confirms that MATLAB/Simulink is an effective tool for the analysis and development of model-based control systems.