3-AXIS NEAR-MINIMUM-TIME MANEUVERS OF RESHAPE - NUMERICAL AND EXPERIMENTAL RESULTS

Numerical and experimental results of the minimum-time and near-minimu m-time maneuvers of a rigid structure are presented. A numerical algor ithm based on the quasilinearization method with time shortening strat egy and a shooting method has been developed to obtain the open-loop s olution of the time-optimal control problem. The experiment is perform ed on the Naval Research Laboratory's Reconfigurable Spacecraft Host f or Attitude and Pointing Experiments (RESHAPE) three-axis maneuver fac ility. In the experiment, this open-loop control solution provides the ''feedforward'' control command and state trajectories which the syst em is required to follow. A second loop, a state-error feedback contro l loop, is then designed to add guaranteed stability to the system, so that small disturbances during the maneuver and post-maneuver-error c an be damped out. Numerical and experimental results are presented to illustrate the success of this method.