While past flight projects involved a single spacecraft in isolation, over forty proposed future missions involve multiple coordinated spacecraft. This paper presents characteristics of such missions in terms ofproperties of the phenomena being measured as well as the rationale for using multiple spacecraft. We describe the coordination problems associated with operating these missions and iden...

This work presents a distributed estimation and control architecture for formation flying spacecraft. We show how spacecraft can individually create a local estimate of the formation and create their own control action using that estimate. Proofs are provided to show that such a scheme is asymptotically stable and spacecraft will reach consensus on the formation states.

Efficient algorithms for collision-free energy sub-optimal path planning for formations of spacecraft flying in deep space are presented. The idea is to introduce a set of way-points through which the spacecraft are required to pass, combined with parameterizations of the trajectories which are energy-optimal for each spacecraft. The resulting constrained optimization problem is formulated as a...

GPS is increasingly being used for a wide range of applications. Its use for spacecraft navigation has been already demonstrated for absolute real-time positioning and precise orbit determination. Now, in preparation for the proximity navigation of the ESA Automated Transfer Vehicle (ATV) around the International Space Station, spacecraft relative navigation using GPS has to be demonstrated. Fo...

Operating robotic scientific spacecraft is a complex process. To reduce operating costs and risks, there has been much discussion of the requirements for automating spacecraft operations as well as automating the spacecraft themselves. It is not always easy to determine which features to automate in space, which ones to automate on the ground, and which functions would best remain in human hand...

This paper presents general stability conditions for a spinning spacecraft with partially liquid-filled tanks by using Rumyanstev and Mclntyre methods. These methods are compared for accuracy and limitation by applying them to a specific case of a spinning spacecraft with two partially liquid-filled tanks. The stability conditions require that, for a stable motion, the spin to transverse moment...

Spacecraft software automatic testing plays an essential role in spacecraft testing field for a decade. However, less attention has been paid on it based on workflow methodology. In this paper we introduce workflow technology into testing for improving the automation of spacecraft software testing. Firstly we present a spacecraft testing process definition language STPDL. Then workflow patterns...

This paper considers the problem of reorienting a constellation of spacecraft such that the fuel distributed across the constellation is both conserved and expended uniformly. The spacecraft constellation is controlled to reorient while maintaining the relative positions of the spacecraft such that the constellation is held in formation throughout the maneuver. The basic idea is to pick a point...

This paper addresses the distributed attitude synchronization problem of multiple spacecraft with unknown inertia matrices. Two distributed adaptive controllers are proposed for the cases with and without a virtual leader to which a time-varying reference attitude is assigned. The first controller achieves attitude synchronization for a group of spacecraft with a leaderless communication topolo...

We propose the use of a model helicopter to emulate the landing dynamics of a spacecraft. Our controller accepts thruster inputs (like those on a spacecraft) and converts them into appropriate helicopter stick controls such that the resulting trajectory of the helicopter is close to the trajectory that would have been achieved by simply providing the same thruster inputs to a spacecraft. The ap...