Abstract
The nonlinear satellite dynamics, including gravitational perturbations of zonal harmonics up to is utilised to search for the optimal fuel cost for maintaining a formation is investigated. The system dynamics were developed in an Earth-centred inertial coordinate frame using the methods of Hamiltonian dynamics. Continuous dynamic optimisation theory was used to minimise fuel requirements, resulting in a continuous thrust. The uncontrolled reference trajectory of the formation was restricted to a circular inclined orbit. Additionally, further fuel savings are discussed with possible modifications to orbit altitude, formation radius, and variations in the defined performance index.