Dynamic modelling and control of a flexible spacecraft with fuel slosh

Modern spacecraft often contain large quantities of liquid fuel to execute station keeping and attitude maneuvers for space missions. In recent works a hybrid control method based on input shaping technique and feedback linearization for liquid-filled spacecraft maneuvers has been proposed to guarantee that the attitude maneuver does not excite the liquid-fuel slosh. In general the combined liquidstructure system is very difficult to model, and the analyses are based on some assumed simplification. A realistic representation of the liquid dynamics inside closed containers can be approximated by an equivalent mechanical system. The technique of equivalent mechanical models can be considered a very useful mathematical tool for solving the complete dynamics problem of a system containing liquid Thus they are particularly useful when designing a control system or to study the stability margins of the coupled dynamics The commonly used equivalent mechanical models are the mass–spring models and the pendulum models.