DESIGN AND ANALYSIS OF INFLATION SYSTEM FOR GOSSAMER SPACE STRUCTURE

Abstract

Inflatable space structures, also called as ‘space inflatables’ have shown immense promise for a very wide and diverse applications in the space sector. Their most significant characteristics are that they require less volume for storage, are less complex and can be deployed easily from their stowed state to the final deployed state, thereby forming lightweight and varied size space structures. The basic building-block structural elements for most space inflatable structures are long beams and struts and are called inflatable booms. The booms act as the structural members for trusses, supporting member for the reflector of an inflatable antenna or support structures of solar arrays, solar sails and other applications. When they are stowed in their compact state, they are very flexible folded or coiled up for achieving high packaging efficiency or a high deployment ratio. After they are launched in space, the compactly stored booms are inflated for achieving their structural properties. The booms will be stabilized by an internal pressure and do not require rigidisation for small space missions lasting for only a few days. However, rigidisation becomes necessary for missions of long lives. They may be rigidized using many rigization methods available for these inflatable space structures for survival and functional performance for long-term space missions. Also, a very critical aspect of designing booms for space applications is the packing method for deploying reliably. The choice of packaging method significantly affects the inflation process and the deployment dynamics. In this work, an inflation method called the residual air inflation method or self-inflation method is presented for such cylindrical booms of different lengths using the classic bellow fold pattern and the Yoshimura fold patten. The Z-fold was not found suitable for the use of this inflation method. The pressures required for full inflation of different lengths of booms are compared and the inflation simulations are observed in Abaqus/CAE.