Ground Testing of Magnetically Suspended Reaction Wheel

The objective of the Phase I effort is to develop a design configuration of a magnetically suspended reaction wheel for a small satellite. This configuration will be developed in close collaboration with well-known commercial suppliers of reaction wheels. It will use novel magnetic bearings that are radially passive and made of permanent magnets with high energy density. These bearing are robust, thus facilitating high speed operation. These use only one actively-controlled axis, thus saving the power that otherwise would have been consumed by the complex control electronics. These novel magnetic bearings support the reaction wheel without contact, thus ensuring long life. In Phase I, we will develop the design configuration of the reaction wheel for a typical small spacecraft. This will be accomplished by conducting a complex trade analysis between the low-power, light weight and high torque requirements of the reaction wheel and the speed, stiffness and damping capabilities of magnetic bearings. The analytical configuration development effort will be enforced by an experiment task to test critical bearing elements for their high speed operational capability. An optimally designed magnetically suspended reaction wheel design configuration is the end result of this effort. Benefits: Successful development of these reaction wheels will be useful in a growing number of commercial satellites such as IRIDIUM and TELEDESIC. These reaction wheels will also enhance commercial applications of space such as cellular phones, remote sensing and surveillance. The passive magnetic bearings developed herein can also be used in several energy storage devices such as electric vehicles, utility power storage, etc. They also find applications in many markets such as refrigerators, auxiliary power units, air cycle machines and machine tool spindles.|