Editing Reaction wheel (section)

== Similar devices ==

A [[control moment gyroscope]] (CMG) is a related but different type of attitude actuator, generally consisting of a momentum wheel mounted in a one-axis or two-axis [[gimbal]].<ref name=smad/>{{rp|362}} When mounted to a rigid spacecraft, applying a constant torque to the wheel using one of the gimbal motors causes the spacecraft to develop a constant angular velocity about a perpendicular axis, thus allowing control of the spacecraft's pointing direction. CMGs are generally able to produce larger sustained torques than RWs with less motor heating, and are preferentially used in larger or more-agile (or both) spacecraft, including [[Skylab]], [[Mir]], and the [[International Space Station]].