Distributed Control of Spacecraft Formations via Cyclic Pursuit: Theory and Experiments

In this paper, distributed control policies for spacecraft formations that draw inspiration from the simple idea of cyclic pursuit are studied. First studied are cyclic-pursuit control laws for both singleand double-integrator models in three dimensions. In particular, control laws are developed that only require relative measurements of position and velocity with respect to the two leading neighbors in the ring topology of cyclic pursuit and that allow convergence to a variety of symmetric formations, including evenly spaced circular and elliptic formations and evenly spaced Archimedes spirals. Second, potential applications are discussed, including spacecraft formation for interferometric imaging. Finally, experimental results obtained by implementing the aforementioned control laws on the Synchronized Position Hold Engage Reorient Experimental Satellite testbed onboard the International Space Station are presented and discussed.