Optimization of Solar Sail Logarithmic Spiral Transfers by Computing and Comparing Energy and Time Requirements with Different Orbital Inclinations and Yaw Angles

Conventional space craft are limited in their ability to deliver high energy missions by a fundamental reliance on fuel mass. However, this constraint can in principle be dealt with class of propellantless propulsion system which extract momentum from the flux of photons that are continually emitted from the Sun - like a solar sail. Solar sails are able to provide a large amount of ∆V for long duration and high energy missions, also providing continuous acceleration. Modern solar sails are also equipped with Thrust Vector Controlling (TVC) mechanism. Even with an edge over conventional spacecraft, there is one difficulty that arises with the use of solar sails - a problem termed ”The Orientation Problem”. ”The Orientation Problem” addresses the idea of how changing the yaw angle of a sail to achieve a high impulse, changes the eccentricity and inclination of an orbit by providing ∆V to the radial and normal vectors. This problem, if encountered, can lead to vast changes in orbital characteristics (inclination, eccentricity) which hinders the transfer trajectory and increases the intercept time and ∆V requirement. In this paper we will compute and analyze a number of different transfers for a solar sail at different orbital inclinations and yaw angle (angle between the normal and sail-sun line) for which we completely mitigate(in some cases) or account for(in majority cases) for the ”Orientation Problem” to find the most optimum orbital inclination and a particular yaw angle at the point of the burn for the specific inclination which gives the best combination of mission duration and energy requirement for a transfer from Earth to Venus using a sail.