Dynamics and Control of Unmanned Spacecraft Rendezvous and Docking

Abstract: This paper presents a study on spacecraftRendezvous and Docking (RvD) through a comprehensiveliterature review, in addition to investigate the main phases andpossible control methods during the space rendezvous and docking.It presents a study of different energy efficient far rangerendezvous (e.g. Hoffman, bi-elliptic, phasing maneuver etc.). Aset of formation flying models (i.e. relative navigation) for twospacecraft operating in close proximity are examined. Oneapproach to depict the relative orbit’s dynamics model for closeproximity operations is to mathematically express it by thenonlinear equations of relative motion (NERM), that present thehighest accuracy and are valid for all types of orbit eccentricitiesand separations. Another approach is the Hill-Clohessy-Wiltshire(HCW). This method is only valid for two conditions, when thetarget satellite orbit is near circular and the distance between thechaser and target is small. The dynamics models in this paperdescribe the spacecraft formation flying in both unperturbed andperturbed environment, where only the Earth oblatenessperturbations are being treated.Furthermore, this paper presents a design of a control, guidance,and navigation (GNC) based on the aforementioned dynamicmodel. This will enable the chaser satellite to autonomouslyapproach towards the target satellite during the close proximitynavigation using some control techniques such Linear QuadraticRegulation (LQR) and Linear Quadratic Gaussian (LQG). Thesecontrol techniques aim to reduce both the duration and the ΔVcost of the entire mission.