Development of a self deployable structural element for space truss applications

This research work presents the results of an on-going development program on an advanced composite Self Deployable Structural Element (SDSE). Deployable space structures can either be fabricated and assembled on earth and subsequently deployed in space or assembled in orbit with raw materials transported to the site by a launch vehicle. It is beneficial to pack and stow a collapsed structure in a minimum volume configuration. Ideally, this structure will deploy at the site without human intervention. Such a structure is flexible in its unheated state, allowing it to be folded and compactly stowed in the space vehicle. It is formed of a core of thermally activated expanding foam or pressurizing agent, an internal bladder, a load carrying member of braided advanced composite material, and an outer retaining jacket. The core material, upon heating with a resistance wire, internally pressurizes the structural element which leads to deployment. The same heat source also cures the advanced composite material.