Design and Test of a 100 μN-class Thrust Stand for a Miniature Water Ion Thruster with CubeSat

The electric propulsion system for CubeSat is required to achieve various missions. A miniature water ion thruster for CubeSats has been proposed and tested. To investigate the effect of the dissociation of water on its performance, a direct thrust measurement is required. In this study, a 100 μN-class thrust stand for 10 kg units was designed and integrated. It was calibrated using weights whose mass was measured in advance and achieved the measurement of the thrust of the miniature ion thruster using water. The range of measured thrust was 60–140 μN, and the average of its uncertainty was ±7.6 %. The thrust coefficients were around 0.9, similar to or slightly less than that of xenon. This shows that the dissociation of water has little effect on the thrust.