Optimal control of cluster satellites for improved remote sensing

The concept of flying spacecraft in formation is revolutionising our way of performing space-based operations, and this new paradigm brings out several advantages in space mission accomplishment and extends the possible application area for such systems. Spacecraft formation flying is a technology that includes two or more spacecraft in a tightly controlled spatial configuration, whose operations are closely synchronised, and Earth and deep space surveillance are areas where spacecraft formations can be u seful. These applications often involve data collection and processing over an aperture where the resolution of the observation is inversely proportional to the baseline lengths. Hence, several distributed observations can increase the resolution and allo w for computation of physical quantitites which cannot be derived from one single measurement. Further exploration of neighbouring galaxies in space can only be achieved by indirect observation of astronomical objects, and space based interferometers with baselines of up to ten kilometres have been proposed. However, to successfully utilise spacecraft formations for this purpose, accurate synchronisation of both position and attitude of the cooperating spacecraft is vital, depending on accurate dynamical system models of the formation. Furthermore, the satellite cluster must be operated in a way which is optimal as seen from the end user of the data collected by the cluster. The main object of this project is to establish a connection between the goals of the end user of the observations, and the control of the satellites, such that the observations can be collected in a way which is optimal to end user. On the way towards this goal, there are several challenges connected to the derivation of accurate dyn amical models for the cluster of satellites