A review of technology developments in flywheel attitude control and energy transmission systems

In the past decade there has been an upswing in the interest of flywheel energy storage systems for space applications. This interest has been driven by limitations of chemical batteries for Air Force mission concepts, advances in microprocessors and composite materials, and the promise of using flywheel systems for energy storage and as attitude control actuators. The primary issues are power efficiency, mass and size, and long-term stability. Flywheels as one-to-one replacements for spacecraft batteries are competitive for only a few special missions. When flywheels replace components in two major bus subsystems, the potential weight and volume benefits are attractive. The objective of this paper is to describe the progression of flywheel technology state-of-the-art for integrated power and attitude control (IPAC) systems in space applications, and describe current AFRL efforts. The main technology areas that are addressed in this paper are flywheel designs, bearings containment and safety, and combined power distribution and attitude control.