Abstract: Momentum wheel speed correction in an orbital space vehicle that corrects for the oscillation resulting from spurious variations in the angular velocity of the momentum wheel. The momentum wheel's angular velocity is subject to random fluctuations due to Coulomb forces. These fluctuations are coupled into the vehicle's spin rate causing errors in the yaw rate and yaw. By adding corrective values to the determined yaw rate and yaw by selectively filtering the momentum wheel tachometer signals, pointing errors are substantially reduced or even eliminated.

Abstract: Apparatus and method for performing error checking and syndrome generation on multibit characters of blocks of messages. The characters are processed ad seriatim and the symbols or syndromes are accumulated until all characters of a block have been processed. The check symbols are concatenated with the associated message block while the check symbols are accumulated for the next block. If there is a nonzero syndrome, the accumulated syndromes can be extracted while the syndromes for a next block are being generated.

Abstract: A novel method and apparatus for dynamically monitoring the friction associated with an electromechanical system including a motor. The apparatus includes a closed loop servo with a unique filtering means in the feed forward loop for controlling the phase and magnitude of a "digital" ramp function used to drive the electromechanical system. The value of the filtered error signal outputted from the filtering means correlates with the friction in said electromechanical system.