control
Sayyed Mohammad Mousavi; Sayyed Majid Esmailifar; Mohammad Chiniforoushan
Abstract
This paper studies the time-optimal 6 degrees of freedom (6DOF) orbital rendezvous maneuver problem for an inertially asymmetric rigid spacecraft with independent attitude and position control actuators. It is assumed that the spacecraft equipped with the thruster actuators and the control forces and ...
Read More
This paper studies the time-optimal 6 degrees of freedom (6DOF) orbital rendezvous maneuver problem for an inertially asymmetric rigid spacecraft with independent attitude and position control actuators. It is assumed that the spacecraft equipped with the thruster actuators and the control forces and torques are generated along the three principal axes of the spacecraft. In order to obtain the time-optimal 6DOF maneuver state and control trajectories, at first, the relative translational and rotational dynamics of the spacecraft are described. Then, the Gauss pseudospectral method is used to solve the time-optimal control problem in the presence of constraints on control forces and torques. Also, the costates are estimated to first-order optimality proof of the obtained solutions. Numerical simulation results show that for the assumed time-optimal 6DOF maneuver problem, the control structure for all of the control forces and torques is ‘bang-bang’. Eventually, the optimality of the obtained solutions is verified by checking the fulfillment of Pontrygain’s minimum principle.
