Abstract - Spacecraft formation flying technology is opening new scenarios for future space missions. It is a relatively young technology and it is a field of ongoing research. This document describes the design features, and the design choices, of a testbed that allows to carry on experimental research on spacecraft formation flying in an earthbound laboratory. The work is part of the spacecraft formation flying related activities conducted at the University of Padova. The facility developed is composed by two spacecraft, each representing a spacecraft of a simple formation, and it will allow to study the three dimensions attitude dynamics.