In the latest years, small satellites are becoming more and more utilised by space agencies, thanks to their reduced costs. The technological improvement and the large choice of Components of the Shelf, allowed the space industry to develop smaller and cheaper satellites, able to operate in different missions and scenarios. Due to their limited mass and volume, they can be launched simultaneously with only one launcher, cutting enormously the launch costs. They can be disposed as a constellation and provide services for communications, Earth observation, science experiments or debris removal. All these aspects allowed the non-governmental companies and universities to have access to the space, improving the research of reliable and increasingly smaller satellites, like CubeSats.