Non-ideal solar sailcraft time-optimal rendezvous mission

The time-optimal rendezvous mission with a non-ideal solar sail spacecraft is studied with the three-dimensional dynamics equations constructed using the optical sail force model. Only the solar gravitational force and solar radiation pressure force are considered in the model. The time-optimal control model is derived using an indirect method with consideration of the launch window. An optimal control law for optical sails is presented. The non-ideal sail coefficients of the National Aeronautics and Space Administration (NASA) are used in simulations of the Venus rendezvous mission with lightness number of 0.05 to 0.1 for comparison with the ideal sail. The simulations show that the influence of the non-ideal sail should be considered in the orbit design due to the longer flight time and different attitude control profile compared to the ideal model.