Design,modeling and experimental investigation of a novel solar sail with high area-to-mass ratios for efficient solar sailing

Solar sailing is a promising propellant-free approach to propelling spacecraft in space.However,the propelling efficiency of conventional solar sail spacecraft is limited by their areato-mass ratios.This paper proposes a novel design of micro solar sails with area-to-mass ratios above 100 m2/kg for next-generation chip-scale spacecraft.Bilayer thin films developed by Microelectromechanical Systems(MEMS)technologies were patterned into grid microstructures,and theoretical analysis of a sail prototype was conducted.The electro-thermal and thermo-mechanical models of the solar sail in geospace were established by taking effects of Joule heating,solar radiation,and thermal re-emission into consideration,enabling rapid prediction of its threedimensional(3-D)reconfiguration from the as-released two-dimensional(2-D)microstructure.Adjustment of the ChipSail’s acceleration arising from the sail’s morphing was also analytically modeled.Fabrication and characterization of the sail prototype made of multiple Al/Ni50Ti50 bilayer beams were accomplished.In-situ SEM imaging of the sail prototype in vacuum chamber witnessed an active and continuous 3-D reconfiguration under Joule heating,and over 90deformation was detected by applying a DC voltage of 0.078 V.Theoretical and experimental work on the solar sail with at least 10 times higher area-to-mass ratios than conventional ones will lay a solid foundation for efficient solar sailing.