Deployment/retrieval control of a tethered subsatellite under effect of tether elasticity

This paper studies the deployment/retrieval control of a tethered subsatellite connected through an elastic tether to a main body. The dynamical model of the tether is a continuum and the effect of tether elasticity is taken into account. The equations of motion are obtained as nonlinear, partial differential, and time varying equations, and treated directly without using any approximation of the modal analysis. The Mission-Function control algorithm is applied to the deployment/retrieval control of the subsatellite connected through the elastic tether. Results of numerical simulation show that the present control law works well for the present control problem. The elastic vibrations of the tether are suppressed satisfactorily, and their effects on the control performance are shown not to be crucial.