Development of a thrust balance for microspacecraft electric propulsion units

The development of satellite propulsion systems naturally requires the accurate measurement of the thrust level. Whereas such a task is relatively easy for chemical thrusters where forces in the order of kN are produced, complexity raises with electrical thrusters that show very low thrust-to-mass ratios. Currently the thrust of electric devices is in the µN to hundreds mN range, which makes measurements difficult and complicated. Moreover, thrust measurements must be carried out inside a vacuum chamber in order to comply with the effective environment in which satellites, then thrusters, operate. This Master thesis presents the development of a pendulum-type Thrust Balance able to measure the low thrust produced by miniature electric thrusters. The work covers architecture selection, mechanical simulation, CAD, balance building, control unit and DAQ design, testing and preliminary measurements with a low-power Hall thruster. The project was performed during a six-month internship held at the CNRS-ICARE laboratory in Orléans within the Electric Propulsion (EP) team, a group of researchers studying and designing low-power electric propulsion systems.