Design and characterization of a small-scale solar sail deployed by NiTi Shape Memory actuators

Solar sails exploit the radiation pressure as propulsion system for the exploration of the solar system. Sunlight is used to propel space vehicles by reflecting solar photons from a large and light-weight material, so that no propellant is required for primary propulsion. Kapton seems to be the most suitable material for the sail production and in the space missions till now activated booms as deployment systems have always been used. In this work a self deploying system based on NiTi Shape Memory wires has been designed and manufactured in a small-scale prototype. As kapton has always been employed with a thin Al coating on one or both surfaces of the sail, for the first experiments commercial pure Al thin sheets have been used in order to simulate the sail. In the small-scale prototype manufactured, three different configurations have been studied for bending the sail while two different Nitinol wires have been used as active materials for the self-deployment of the sail. Infrared lamps have been employed in order to warm the solar sail and obtain the activation of the shape memory active elements.