Abstract
Space launch vehicles provide a very limited and expensive allowance for new satellites to be put into orbit, so that spacecraft manufacturers are subjected to stringent constraints in terms of volume. Moreover, the mass budget and the overall complexity of subsystems play a signifi- cant role, especially in the design of small platforms. Deployable structures address such issues as they require smaller volumes and allow for less complicated and lighter weight mechanisms. Extendable appendages such as composite STEM booms have thermal-mechanical behaviour that could be detrimental for in-orbit operations, as they can undergo deflection accompanied by possibly unstable thermal vibrations. For high accuracy applications, a prediction of the structural performance under space environment conditions is crucial. In this paper the interaction between composite slit tubes and Solar heat flux is studied through an analytical model and finite element simulations. The main motivation is to examine the feasibility of a support structure for a telescope secondary mirror featuring coilable booms. The possibility of scaling the subsystem from nanosatellites to bigger platforms could be appealing in the Earth Observation market. The effects of changing geometrical and material parameters will be explored, especially the impact of the number of plies, stacking sequence and the uncertainties related to the thermal properties of composites. Finally, a finite element model of the telescope assembly under Solar heat flux will be analysed.