Fuel/time optimal control of flexible space structures

This paper considers the design of open loop Fuel/ Time optimal controllers for flexible space structures using a frequency domain approach. The control system consists of a time delay filter whose output signal is the optimal control profile when it is subject to a step input. A constrained parameter optimization problem is formulated to minimize a weighted combination of fuel consumed and total maneuver time for a rest-to-rest maneuver. The parameters to be optimized for are the delays of a time-delay filter. The number of switches of the fuelltime optimal control profile is shown to be a function not only of number of flexible modes but also of the weighting parameter, which is illustrated via numerical examples.