Numerical Analyses of an Energy Loaded Joint for a Deployable Satellite Structure

Abstract

Reflectors which are an integral part of space vehicles must be collapsed into the body of the vehicle for transportation to space. It is not efficient to store solid reflectors with a diameter greater than about 2.5 m in the launch vehicle and consequently deployable reflectors are used. This paper discusses the use of a flexible joint mechanism to enable a large reflector to be folded to a compact size and then deployed at geosynchronous orbit. The joint would be incorporated into the members of a skeletal truss structure and their effect on the dynamic behaviour of a single structural member and a large truss framework has been studied. It has been shown that the resonant behaviour of a structural member was significantly altered by introducing a joint into the system, but that of large trusses was not as seriously affected and resembled the equivalent of a non-jointed structure. The resonant frequencies of the jointed structure are shown to be similar to those of the non-jointed one but the amplitudes of vibration are significantly lower.