Analytical and Experimental Investigation of Stabilizing Rotating Uncooperative Target
by Tethered Space Tug
Junjie Kang, Zheng H. Zhu, Lucas F. Santaguida
Abstract: Attitude stabilization of a massive rotating uncooperative target by a tethered space tug is studied for orbit maneuvering in the postcapture operation analytically and experimentally. The perturbed orbital propagation of the tethered space system is described with nonsingular orbital elements and the relative equations of motion of the tethered space system, including the tether libration and attitudes of target and tug, are established in the orbital frame. The tether tension control, the tug's attitude control, and the combination control of them are designed to suppress the attitude and libration motions of the target/tug and the tethered space system with bounded stability. The control law's effectiveness is demonstrated by simulation and then validated experimentally by a microgravity testbed with two tethered free-floating air-bearing satellite simulators.