%0 Journal Article
%T Guidance Navigation and Control for Autonomous Multiple Spacecraft Assembly: Analysis and Experimentation
%A Riccardo Bevilacqua
%A Marcello Romano
%A Fabio Curti
%A Andrew P. Caprari
%A Veronica Pellegrini
%J International Journal of Aerospace Engineering
%D 2011
%I Hindawi Publishing Corporation
%R 10.1155/2011/308245
%X This work introduces theoretical developments and experimental verification for Guidance, Navigation, and Control of autonomous multiple spacecraft assembly. We here address the in-plane orbital assembly case, where two translational and one rotational degrees of freedom are considered. Each spacecraft involved in the assembly is both chaser and target at the same time. The guidance and control strategies are LQR-based, designed to take into account the evolving shape and mass properties of the assembling spacecraft. Each spacecraft runs symmetric algorithms. The relative navigation is based on augmenting the target's state vector by introducing, as extra state components, the target's control inputs. By using the proposed navigation method, a chaser spacecraft can estimate the relative position, the attitude and the control inputs of a target spacecraft, flying in its proximity. The proposed approaches are successfully validated via hardware-in-the-loop experimentation, using four autonomous three-degree-of-freedom robotic spacecraft simulators, floating on a flat floor. 1. Introduction The technical difficulties presented by the autonomous multiple spacecraft assembly problem relate to the development of robust and reliable guidance, navigation, and control techniques for on-orbit evolving systems. The main open challenges are: (1) propellant-efficient control of an assembling (also known as evolving system), the evolution occurring both in its mass and inertia properties, as well as in its sensors and actuators configuration and (2) accurate relative navigation among the spacecraft, especially in the event of low frequency measurements update and interruptions of measurements due, for example, to relative sensors¡¯ view¡¯s obstruction by other spacecraft. The works of [1¨C4] address specifically the problem of a system¡¯s evolution and its control. In [5], more emphasis is given to a potential solution for the wireless connectivity of different parts intended for the assembly of a bigger spacecraft, where a Wi-Fi bridge acts as the only real ¡°assembly.¡± Furthermore, wireless capability is becoming a more relevant option for exchanging data amongst close proximity spacecraft which eventually dock to each other (see [6]). Also, the high-risk situation of an assembly maneuver in space does not leave room for computationally intensive logics, such as optimal controllers (see [7]). Onboard CPUs must allocate most of their performance capabilities to platform safety issues. The use of Commercial Off-The-Shelve (COTS) relative sensors, such as low-cost cameras,
%U http://www.hindawi.com/journals/ijae/2011/308245/