2014 Volume 62 Issue 3 Pages 85-92
The principal function of a control system for a small vehicle is to generate or counteract its angular momentum. A straightforward approach to exerting control torque is to use three separate flywheels with motors in a mutually orthogonal arrangement. This paper describes the development of a three-dimensional reaction wheel using a spherical rotor that can reduce the number of flywheels from three to one. Therefore, the proposed system can be applied to a small satellite with space and weight limitations. The system consists of the spherical rotor, three piezoelectric actuators as the stator, and optical sensors. The spherical rotor can rotate around arbitrary axes without a very complex mechanism using gears, links, and special mechanism. A feedback control system is designed to control the angular velocity vector of the spherical rotor. The performance of the proposed system is verified through preliminary experiments.
