Abstract Due to its propellantless nature, a solar sail can provide the primary propulsion system for a high energy mission, such as that of a multiple asteroid rendezvous. Upon arrival at an asteroid, it is often desirable to interact with the surface of the body, such as for sample extraction. The deployment of a lander from a solar sail carries the difficulty of an instantaneous, and sometimes considerable, change to the system dynamics at the point of separation. This paper investigates the effects of changing sail performance during the release of multiple “ChipSat” probes as well as a large MASCOT-type lander and the control of the sail into a positional hold at an equilibrium point or periodic orbit. In one scenario, 20 ChipSat probes are released, with one-hour spacing between each release. The sail is then controlled to maintain the sailcraft close to the initial deployment point. The performance of a Linear Quadratic Regulator (LQR) is compared with maintaining a fixed sail attitude after deployment. In a second scenario, at the point of separation of the larger MASCOT-type lander, there will be a considerable instantaneous change in the sail characteristic acceleration, as opposed to the gradual small change for the staggered deployment of the small ChipSat probes. It is shown that the Time-Delayed Feedback Control (TDFC) method is effective in controlling the orbit of the sail after this deployment. The sail converges to an orbit in the same region of phase space when deployment is made from both a lower and higher inclination orbit.

Highlights • Control of the sail at the point of, and subsequent to, the lander/probe deployment • Comparison of fixed-attitude and LQR control for ChipSat deployment • Time-Delay Feedback Control applied after MASCOT-type lander deployment