Enhanced attitude control structure for small satellites with reaction wheels

Abstract

Purpose

This paper aims to describe a design enhancement for the satellite attitude control system using reaction wheels, and the wheel momentum unloading using magnetorquers.

Design/methodology/approach

The proportional – integral–derivative-controller and active force control (AFC) schemes are developed together with their governing equations for closed loop system of attitude control. Four numerical simulations were carried out using the Matlab – Simulink™ software and results were compared.

Findings

From the results, it is evident that the attitude accuracies for roll–pitch–yaw axes have improved significantly through the proportional – derivative (PD) – AFC controller for the attitude control and the wheel momentum can be well maintained during the momentum unloading scheme. The results show that the AFC has a high potential to be implemented in the satellite attitude control system.

Practical implications

Using AFC, the actual disturbance torque is considered totally rejected by the system without having to have any direct prior knowledge on the actual disturbance itself.

Originality/value

The results demonstrate the satellite attitude control using reaction wheel is enhanced by PD–AFC attitude controller.

Citation

Ismail, Z., Varatharajoo, R., Ajir, R. and Mohd Rafie, A.S. (2015), "Enhanced attitude control structure for small satellites with reaction wheels", Aircraft Engineering and Aerospace Technology, Vol. 87 No. 6, pp. 546-550. https://doi.org/10.1108/AEAT-06-2014-0085