On the dynamics of spinning tethered space vehicles (Q2781020)

The concept of tethered satellite systems, that is, two or more satellites connected by thin and long cables in orbit -- a length of 100~km is not unusual -- has been developed in the last decades of the 20th century resulting in several space flights. There exists a broad spectrum of practically important applications ranging from energy production, making use of the magnetic field of the Earth, to orbit raising or deorbiting of satellites by cutting the tether in the stable radial relative equilibrium position on a circular orbit. So far in several space missions flown by NASA the use has been made of the above-mentioned relative equilibrium. NEWLINENEWLINENEWLINEIn the paper under review the authors extend current studies by modelling Canadian Oedipus-C mission which is characterized by the spin of the end bodies along with the tether in order to stabilize the payload. The authors point out that for spinning tethers it is crucial that in modelling the system the bending stiffness is taken into account. For a massive cable model and rigid end bodies, the equations of motion are derived and then are discretized by Galerkin approach resulting in a set of nonlinear ordinary differential equations. Due to their accurate modelling, the authors are able to explain deviations in attitude experienced in Oedipus-A mission flown 1989, and consequently these deviations could be avoided in Oedipus-C mission flown six years later. NEWLINENEWLINENEWLINEThis is an important paper which gives a good survey of recent developments in this new and very promising technology of space exploration.