Time and covariance threshold triggered optimal uncooperative rendezvous using angles only navigation

Abstract

In Micro/Nano-satellite based active debris removal (ADR), the most promoted relative navigation method is angles-only navigation (AON), the relative state estimations are computed from a low-volume/mass, power saving, and low-cost optical/infrared camera's observations, but the uncooperative rendezvous faces drawback of range-observability problem. Based on the drawbacks of the extended Kalman filter (EKF), a more accurate on-board square root unscented Kalman filter (SRUKF) AON scheme is developed, along with a closed-loop linear covariance analysis model. By balancing fuel consumption, control accuracy, and trajectory robustness, we developed a smarter time and covariance threshold triggered optimal maneuver planning method and showed how these results correlate to past methods and missions, and how they could potentially influence future ones. Numerical simulation proved that it is feasible to control the two-line element (TLE) level of an uncertain initial relative state to a 100-m v-bar relative station keeping point, under a 30% data gap per orbital period on account of the eclipse.