Abstract: Methods are provided for calibrating a tachometer or generator device to reduce residual errors associated with the tachometer-generator device. A shim structure is positioned within the air gap of the tachometer-generator device. A physical characteristic or location of placement of the shim structure is selected to reduce variation in an output voltage of the tachometer-generator device.

Abstract: A system and method are provided for operating a control moment gyro (CMG) in a spacecraft. The CMG includes a spin motor, and a CMG rotor that is coupled to the spin motor and is configured to rotate about a spin axis. Electrical power from a power source is supplied to the spin motor to rotate the CMG rotor about the spin axis. A determination is made as to whether the power source can supply sufficient electrical power to the spin motor. If the power source cannot supply sufficient electrical power to the spin motor, the spin motor is rotated by the CMG rotor to generate and supply electrical power to the power source.

Abstract: Methods and apparatus are provided for active motion damping of a spacecraft whose attitude control system (SACS) has experienced a partial failure. In a preferred embodiment, the apparatus comprises, an attitude control processor (ACP), a motion damping controller (MDC) coupled to the ACP, a control moment gyro (CMG) comprising a gimbal loop controller (GLC) coupled to the MDC and a gimbal motor with input coupled to the GLC and gyroscopic torque output coupled to the satellite. Normally, a gimbal rate command (GRC) from the ACP passes to the GLC for execution to rotate the CMG gimbal and the coupled satellite. If the ACP output becomes invalid, the MDC assumes control and can modify CMG operation in several ways to safely decelerate a moving satellite without hazardous mechanical stress. Following such active motion damping, the CMG remains quiescent until a RESET is received whereby further valid GRCs are then executable.

Abstract: Methods are provided for calibrating a tachometer or generator device to reduce residual errors associated with the tachometer-generator device. A shim structure is positioned within the air gap of the tachometer-generator device. A physical characteristic or location of placement of the shim structure is selected to reduce variation in an output voltage of the tachometer-generator device.

Abstract: A system and method are provided for operating a control moment gyro (CMG) in a spacecraft. The CMG includes a spin motor, and a CMG rotor that is coupled to the spin motor and is configured to rotate about a spin axis. Electrical power from a power source is supplied to the spin motor to rotate the CMG rotor about the spin axis. A determination is made as to whether the power source can supply sufficient electrical power to the spin motor. If the power source cannot supply sufficient electrical power to the spin motor, the spin motor is rotated by the CMG rotor to generate and supply electrical power to the power source.

Abstract: A tool structure to effect a twisting alignment of carpentry studs for use is arranged to include cooperative first and second legs, with the first leg pivotally mounting a third leg that in turn is secured to the second leg, with a fourth leg secured to the third leg. A fifth leg pivotally mounted above the third leg is arranged for abutment with the fourth leg to effect projection of the second leg relative to the first leg. In this manner, securement of the associated carpentry stud is permitted accommodating its subsequent twisting for alignment and use.