Fixed Thrust Optimal-Fuzzy Combined Control for Spacecraft Formation Flying
The fixed thrust optimal-fuzzy combined formation control method is mainly studied for spacecraft formation flying in circular orbits based on two-body relative dynamics. The linear Hill's equation is used in relative dynamics, and the circular formation in three dimensions is designed. In fuzzy control, relative position, velocity and acceleration errors are selected as fuzzy variables and the multiplication and weighted average principle are introduced into fuzzy inference so as to maximize the reduction of the coupling effect. And since J2 perturbation is known, it will be taken into account effectively in fuzzy control method. In time-fuel optimal control, the simplified relative error model is used and an optimal controller is provided through the minimum principle. Thus, this paper combines both controls above to form the optimal-fuzzy formation control. Optimal control is adopted when relative position errors reach a certain threshold, while fuzzy control works for the small errors lower than that threshold. Finally, to take circular formation as an example, the simulation results demonstrate that not only does the optimal-fuzzy combined control system have a good response performance, but also excels in fuel consumption.
- Transactions of the Japan Society for Aeronautical and Space Sciences
Transactions of the Japan Society for Aeronautical and Space Sciences 47(155), 9-16, 2004-05-04
THE JAPAN SOCIETY FOR AERONAUTICAL AND SPACE SCIENCES