Solar Cube 2U: A Heliogyro Propulsion System for CubeSats

The Solar Cube heliogyro is a CubeSat propulsion system that utilizes reflected solar pressure as its only means of propulsion and attitude control. It has the appearance of a Dutch windmill and employs sail control akin to a helicopter. Four solar reflecting blades made of ultrathin polyimide attach to a central bus. During operation, centripetal tension and chord-wise battens provide stiffness. The system uses collective and cyclic pitch of the blades to control attitude and thrust. For stowage, each blade is rolled onto a spool adjacent to its pitch actuator. For deployment, the spacecraft spins and the blades unroll in a controlled manner. The proposed Phase I effort will focus on fabrication and feasibility testing of a blade assembly, to prove that a sail blade of sufficient area can stow in the proposed volume and can deploy and pitch reliably. Phase II will mature the hardware design and develop the necessary GNC software. Eventually, Solar Cube will help CubeSats become capable of interplanetary operation, and extend their reach to places that are currently unattainable.