Development of a Large Deployable Space Reflector Structure

Abstract

This paper describes the selection, configuration, design and development of the 5 m diameter deployable reflector structure currently being undertaken jointly by British Aerospace Space Systems Limited and the University of Surrey. Large reflectors represent the most likely, near-term application of a large deployable space structure and offer the most promising opportunity for the development and qualification of the hardware required. Such a large, deployable reflector has to compete against other reflector designs which are not suitable for development into larger space structures but are optimized solely as reflector backing structures. These competitors provide a useful measurement of performance against which the development reflector may be compared in terms of mass, stiffness, cost and reliability. The proposed reflector comprises a radio frequency reflective surface of gold-plated molybdenum knitted wire mesh supported from the nodes of a tetrahedral truss. The development 5 m diameter reflector is made from six deployable tetrahedrons configured symmetrically around a central node. Larger reflectors are possible using the same concept with longer struts or by using an extension of this concept with extra rings of tetrahedrons. The solution is dependent upon the required reflector size and stowage volume restrictions. This design has brought together two critical items of hardware for a large deployable space structure: a simple, light, reliable self-latching hinge (developed by the Ministry of Defence and the University of Surrey) and a long, light, stiff, inexpensive carbon fibre tube (manufactured by the pultrusion technique).