Recently, the use of microsatellites, e.g. CubeSat, has increased due to technology miniaturisation. The combination of several microsatellites allows to design large spacecrafts considering a modular approach and reducing costs. Moreover, in case of a component failure, the modularity makes it possible to replace a single spacecraft instead of repairing a larger one. The most critical phase in this concept is the contact among the microsatellites, which is required to be accurate and at low speed, in order to prevent any potential damage. Magnets may reduce design complexity and docking phase during the final approach manoeuvre. The objective of this thesis is the design of a simulator for small satellites docking considering magnets application.