Abstract This project aimed to first develop a basic model that described the coplanar circular orbit of a satellite using equations of motion derived from the 2-body problem. Then Thrust with throttling and directional control was added to this basic model. This allowed the simulation of a continuous thrust coplanar orbit transfer maneuver to be modelled. Next this transfer trajectory was optimised using the Matlab function fmincon. All these models were simulated using Matlab. The investigation also seeks to determine the validity and range of accuracy of the developed models. The original final objective was to use these models as the basis for a simulation of the dispersal of a constellation of Cube Satellites, but this aim was not met. This investigation suceeded in developing the desired basic ciruclar model and then went on to successfully implement thrust, throttling and directional controls. The optimisation process was then successfully conducted to find the optimum set of controls that minised the mass used in a transfer trajectory for orbit changes in the range of 0 – 15000km. Some analysis is also presented on the best way to frame the optimisation problem to get the best results.