Solar sail elastic displacement effects on interplanetary trajectories

Space agencies are paying greater attention to solar sail technologies and missions. Actually, one of the most demanding issues when considering solar sailing is to assess the sail deformation as well as the following trajectory modifications. The main purpose of this paper is to show the order of accuracy that can be reached when coupling structural and dynamical behavior of a solar sail. Based on the application of the Finite Element Method, the deformations affecting the large structure of the sail, up to the second order of accuracy, are estimated, together with the real-time updated thrust vector according to such deformations. The new thrust vector, evaluated for an Earth-Venus mission, allows one to find a more realistic sailcraft trajectory. The results obtained show a change in the thrust's magnitude with a not negligible variation of the sailcraft trajectory with respect to the undeformed case. Another issue deserving particular attention concerns solar sail deployment. Both structural and dynamical behavior affecting a solar sail's performance will be analyzed even in the event of partial deployment. The results obtained show the importance of the right sizing of the attitude control, which may not be able to compensate such a failure and what strategies could be used to save the mission including the need for a new mission analysis. (c) 2012 Elsevier Ltd. All rights reserved.