Propellant-Free Control of Spinning Tethered Formation Flight, Part 1: Linear Control and Experimentation
Chung S, et al. (2008). "Propellant-Free Control of Spinning Tethered Formation Flight, Part 1: Linear Control and Experimentation." Journal of Guidance, Control and Dynamics 31 3: 571-584
We introduce a decentralized attitude control strategy that can dramatically reduce the usage of propellant, by taking full advantage of the physical coupling of the tether. Motivated by a controllability analysis, indicating that both array resizing and spin-up are fully controllable by the reaction wheels and the tether motor, we report the first propellant-free underactuated control results for tethered formation flying spacecraft. This paper also describes the hardware development and experimental validation of the proposed method using the Synchronized Position Hold, Engage, and Reorient Experimental Satellites test bed. In particular, a new relative sensing mechanism that uses six-degree-of-freedom force-torque sensors and rate gyroscopes is introduced and validated in the closed-loop control experiments.