Title: Positioning Control of Two-Phase Hybrid Stepping Motor-Based Antenna Using Adaptive Controller
Authors: Ekene Samuel Echefu, Knnedy Ihemba, C. A. Nwabueze
Volume: 9
Issue: 8
Pages: 8-15
Publication Date: 2025/08/28
Abstract:
Antennas are critical components of satellite communication systems. Considerable research attention regarding automatic positioning of antenna dish for efficient satellite communication using a closed loop control technique to achieve minimum deviation. However, there is still a control problem regarding such as positioning. This work presents positioning control of two-phase hybrid stepping motor (TPHSM) based antenna using adaptive controller. The mathematical model of TPHSM based antenna was established as a transfer function to describe the dynamic behaviour of the system. A Model Reference Adaptive Control (MRAC) system was designed using the modified Massachusetts Institute of Technology (MIT) rule to determine the adaptive gain of the controller. Simulation analysis was conducted for uncompensated TPHSM based antenna positioning control system. The performance of the system was not satisfactory as the resulting actual position was very much larger than the desired position, which resulted in deviation error of 40.4 even though the rise time, settling time, and overshoot were promising with values 0.79 s, 43 s, and 0 respectively. With the introduction of the proposed MRAC, the performance of the system was largely improved using the different adaptive gains (AGs) of values 1, 5, and 10. The adaptive controller in terms for AG = 1, AG = 5 and AG = 10 gave different rise time of 0.46 s, 0.45 s and 0.46 s; settling time of 0.94 s, 0.88 s, and 0.87 s; overshoot of 0, 2.66e-04%, and 0.01%. Simulation conducted assuming step in put disturbance after 5 s revealed that system position was deviated but this was quickly corrected immediately after 0.75 s for each gain of the adaptive controller. Simulations conducted in terms optimal performance indices such as ISE, IAE and ITAE to determine the value of the AG at which the MRAC offers the finest performance showed revealed 5 as the most appropriate. Performance comparison with previous control systems based on PID controller and full state feedback controller (FSFBC) further indicated that the proposed outperformed both by providing the most improved stability and tracking efficiency measured in terms of overshoot and steady state error (SSE). Generally, the proposed MRAC will provide the best point accuracy and stability for the antenna compared to PID and FSFBC techniques.