Saturated Adaptive Relative Motion Coordination of Docking Ports in Space Close-Range Rendezvous

Abstract

An adaptive relative pose controller for docking ports of two uncertain spacecraft in autonomous rendezvous and docking is developed. A novel relative translational and rotational model represented in the chaser body-fixed frame is derived firstly based on the classical Newton-Euler equations. Based on the proposed model, a six-degrees-of-freedom adaptive control law is presented based on norm-wise estimations for the unknown parameters of two spacecraft to decrease the online computational burden. Meanwhile, an adaptive robust control input is designed by introducing an exponential function of states to improve the response performance with respect to the traditional adaptive robust control. Moreover, a linear anti-windup compensator is employed to ensure the bounded performance of the control inputs. The explicit tuning rules for designing parameters are derived based on the stability analysis of the closed-loop system. It is proved in Lyapunov framework that all closed-loop signals are always bounded and the pose tracking error ultimately converges to a small neighborhood of zero. Simulation results validate the performance of the proposed robust adaptive control strategy. Index Terms-Space rendezvous and docking, docking ports, motion coordination, adaptive control, saturated control, model uncertainty. I. INTRODUCTION M ANY important space missions, such as establishment of the space station, on-orbit servicing, space debris removing, and satellite networking [1] require spacecraft rendezvous and docking technique. In the process of the in-orbit rendezvous and docking, two spacecraft, named the active chaser and the passive target, are involved in the scenario. The chaser should conduct large-angle attitude maneuvers and complicated orbital maneuvers approaching to the passive target. Specifically, the close-range rendezvous and docking operations between two spacecraft require highly accurate translational and rotational controllers, since the chaser should fly around the target to track its docking port precisely [2]. In the last few decades, many problems in rendezvous and docking missions have been considered in the control

Full‐state prescribed performance pose tracking of space proximity operations with input saturation

“…The pose kinematics and dynamics of the chaser in frame $$$ {\mathcal{F}}_c $$$ and the tumbling target in frame $$$ {\mathcal{F}}_t $$$ are, respectively, modeled as [43] $$$$ \left\{\begin{array}{l}\dot{\boldsymbol{p}}=\mathcal{A}\boldsymbol{p}+\mathcal{B}\boldsymbol{q}\\ {}\mathcal{M}\dot{\boldsymbol{q}}+\mathcal{C}\boldsymbol{q}=\boldsymbol{u}+\boldsymbol{d}\end{array}\right.\kern0.5em $$$$ and $$$$ \left\{\begin{array}{l}{\dot{\boldsymbol{p}}}_t={\mathcal{A}}_t{\boldsymbol{p}}_t+{\mathcal{B}}_t{\boldsymbol{q}}_t\\ {}{\mathcal{M}}_t{\dot{\boldsymbol{q}}}_t+{\mathcal{C}}_t{\boldsymbol{q}}_t={\boldsymbol{d}}_t\end{array}\right.\kern0.5em $$$$ where $$$ \boldsymbol{p}={\left[{\boldsymbol{r}}^T,{\boldsymbol{\sigma}}^T\right]}^T $$$; …”

Guaranteed Safe Spacecraft Docking with Control Barrier Functions

“…In practice, u in (15) satisfies condition (4) with equality at all points except where (4) allows H 1 to increase at a rate that is unachievable within the input constraints. Since H 1 is constructed with Φ satisfying condition (6), the first constraint on the maximization in (15) will never require H 1 to decrease at a rate that is unachievable within the input constraints. Thus, the maximization in ( 15) is always feasible.…”

“…Autonomous spacecraft rendezvous and docking has been extensively studied, and addressed using several methods, including artificial potential fields (APFs) [7]- [10], path planning [11], model predictive control [12], sliding mode control [13], reinforcement learning [14], and linear control [15], among others. While the fundamental problem almost always centers on the Hill-Clohessy-Wiltshire (HCW) dynamics, different authors have considered various constraints.…”

“…The work in [9], [13] specifically considers APFs for coupled rotation and translation, while [10], [11] consider fuel efficiency as well. The work in [15] considers adaptation to uncertain model parameters, and [11] considers a tumbling target. However, most of the aforementioned works attempt to accomplish docking exactly, or simply report the achieved tolerances when disturbances are added, rather than provably guaranteeing satisfaction of docking tolerances.…”

Learning‐based super‐twisting sliding‐mode control for space circumnavigation mission with suboptimal reaching under input constraints

“…Based on the backstepping technique, Sun et al discussed the 6-DOF control of rendezvous and docking mission under input saturation constraints, and achieved good control response. 2,3 However, different from the classical proximity operations, such as the rendezvous and docking mission, 4 the desired attitude and orbital position of the active satellite in the SCN mission are determined by the relative position between the active satellite and its observation target, which aggravates couplings between the attitude control system and the orbit one. 5 Zhang et al first proposed an algorithm for solving the active spacecraft's desired attitude in the SCN mission.…”