Structural Dynamic Response of a Square Solar Sail under Solar Pressure and Thermal Loading

The solar sail is one of the NASA's high priority advanced space transportation systems. Solar sailing provides a practical way for space exploration missions. Solar sails do not need to carry an active main propulsion system. Through the continuously low thrust propulsion from the solar radiation pressure, the interplanetary transportation for space exploration missions in solar system would be realized. In this paper, dynamic behavior of a square sail under direct solar radiation pressure is investigated. A finite element model of a square sail consisting of four triangular shaped membranes and four pre-stressed tubular booms is developed. Results are presented for different loading cases in order to study effects of straight edge cords and uniform thermal distribution across the sail. It is seen that structural response of the membrane is relatively small in comparison with the sail dimension. Results showed that straight edge cord does not have much effect on the sail structural performance. However, a uniform temperature change across the structure in the structure increases significantly the lateral deformation of the membrane due to the considerable difference between membrane and booms.