• The optimization of an interstellar probe trajectory using a relatively mid performance solar sail is investigated for a single solar photonic assistance. With an approach to a minimum solar distance away from the Sun, solar sails can enable the sailcraft to gain high energy to escape the solar system with a cruise speed of greater than 10 AU/year. Based on a reasonable assumption of a jettison point at 5 AU, a new objective function with a variable scale parameter is adopted to solve the time optimal control problem using an indirect method. In this paper the problem is addressed for an ideal flat sail in the two-body problem. A technique of scaling of the adjoint variables is presented to make the optimization much easier than before. A comparison between the current results and previous studies has been conducted to show the advantages of the new objective function. In terms of the mission time, the influence of the departure point of the sailcraft from the Earth orbit is discussed without consideration of the Geo-centric escape phase, which can be completed by various means. Another interesting discovery is that the angular momentum reversal trajectory is also achieved as a localoptimal solution in a demonstration mission of 250AU. Under the same initial condition, the difference between the two types of solar escape trajectories is discussed in detail through numerical simulations along with the advantages.

author list (cited authors)

  • Zeng, X., Alfriend, K. T., Li, J., & Vadali, S. R.

publication date

  • December 2012