Review A study of reaction wheel configurations for a 3-axis satellite attitude control Zuliana Ismail * , Renuganth Varatharajoo Department of Aerospace Engineering, Faculty of Engineering, University Putra Malaysia, 43400 Selangor, Malaysia Received 16 September 2008; received in revised form 27 October 2009; accepted 10 November 2009 Abstract The satellite reaction wheel’s configuration plays also an important role in providing the attitude control torques. Several configura- tions based on three or four reaction wheels are investigated in order to identify the most suitable orientation that consumes a minimum power. Such information in a coherent form is not summarized in any publication; and therefore, an extensive literature search is required to obtain these results. In addition, most of the available results are from different test conditions; hence, making them difficult for comparison purposes. In this work, the standard reaction wheel control and angular momentum unloading schemes are adopted for all the reaction wheel configurations. The schemes will be presented together with their governing equations, making them fully amenable to numerical treatments. Numerical simulations are then performed for all the possible reaction wheel configurations with respect to an identical reference mission. All the configurations are analyzed in terms of their torques, momentums and attitude control performances. Based on the simulations, the reaction wheel configuration that has a minimum total control torque level is identified, which also cor- responds to the configuration with minimum power consumption. Ó 2009 COSPAR. Published by Elsevier Ltd. All rights reserved. Keywords: Reaction wheel; Satellite attitude control; Momentum management Contents 1. Introduction ............................................................................... 751 2. Reaction wheel control structure ................................................................. 751 2.1. Attitude dynamics and kinematics .......................................................... 751 2.2. Reaction wheel momentum unloading ........................................................ 753 2.3. Reaction wheel control strategy ............................................................ 755 3. Attitude control performances .................................................................. 758 4. Summarization ............................................................................. 758 5. Wheel angular momentum control performance ...................................................... 759 6. Conclusion ................................................................................ 759 References ................................................................................ 759 0273-1177/$36.00 Ó 2009 COSPAR. Published by Elsevier Ltd. All rights reserved. doi:10.1016/j.asr.2009.11.004 * Corresponding author. Tel.: +60 38 9466406; fax: +60 38 6567125. E-mail addresses: zuliana.ismail@gmail.com (Z. Ismail), renu99@gmx.de (R. Varatharajoo). www.elsevier.com/locate/asr Available online at www.sciencedirect.com Advances in Space Research 45 (2010) 750–759