Use of control moment gyros for the stabilization of a spinning satellite
Control moment gyros for spinning satellite stabilization and attitude control
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Control moment gyros for spinning satellite stabilization and attitude control
Control moment gyro /CMG/ for spacecraft attitude control, determining optimal gimbal angle rate for desired torque
Grease lubricated spiral groove bearings suitable for spin axis of gyros in automatic pilots
Control moment gyro fine attitude control system for spacecraft
Stabilizing gyro utilizing re-circulated liquid hydrostatic gimbal bearing
Design and testing of prototype hydrostatic liquid bearing gyro assemblies
Surface evaluation of stainless steel gyro bearings manufactured by various hardening techniques
Gyro dynamic errors in strapdown inertial guidance system due to body rate
Unwanted gimbal rotation friction torques in gyro wheel bearings due to lubrication viscous friction, ball wedging and contamination
High accuracy angular precession measurements with autometric gyro for satellite relativity tests, using optical system with reticle coordinates
Control moment gyro for attitude pointing control system of Skylab space station
Artificial gravity Skylab wobble damping, using ATM control moment gyros
Circuit which integrates spacecraft gyro output voltages to provide analog position signals has been developed. Accurate integration is provided by all solid state system which uses no choppers and takes advantage of commercially available flight qualified components.
Technique is described to reduce extraneous gyro output signals by using relatively inexpensive shrouds which do not increase power comsumption. Shrouds reduce noise by minimizing mass of gas spinning with rotor, reducing Reynolds number near rotor, and inducing laminar flow.
A study was made, leading to development and analysis of a technique allowing the control moment gyro (CMG) momentum vectors to avoid adverse orientations and thus to provide optimal control for the Apollo Telescope Mount. The technique was formulated in terms of a feedback scheme using a check factor, K, formed as the product of the dot products of the three CMG momentum unit vectors. The parameter K approaches unity for all adverse orientations and was used to initiate a single correction maneuver to rotate the CMG momenta away from a pending adverse orientation and to reduce K to an acceptable value. A digital computer program for ATM simulations was modified to incorporate this correction maneuver and performance was evaluated in simulated cases. Antiparallelism was used as the primary example for the evaluation of the feedback optimization technique.
In the field of momentum exchange attitude control systems, single gimbal control moment gyros (SGCMG) are of increasing interest. A gimbal angle approach and a gimbal rate approach are presented for the SGCMG control law including the singularity avoidance. Both approaches are compared and some illustrative examples are given.
The procedure for aligning the inertial reference unit of the space shuttle by celestial references is discussed. The gyro torquing angles required to go from the present stable member to the desired stable member are determined. The inputs are the transformation matrix from the reference to the desired stable member coordinates and the unit vectors to the two target stars in both the reference and present stable member coordinates. The equations involved in establishing the reference are developed.
The design, operation, performance and test of the gyro module and its circuit components are described for the Strapdown Inertial Reverence Unit system.