Figure 3
From: Force probes for development and testing of different electric propulsion systems
(a) View into the HEMP thruster test chamber. The swivel arm with force probe, Faraday cup, and retarding potential analyzer can be seen on the right side. On the left side one sees the thruster together with a dummy of the same mass mounted on the thrust balance. The dummy that is required for this kind of thrust balance hides the thruster behind it. (b) Detected sudden change of the two equilibrium positions (solid and dashed horizontal lines) for the firing (\(t < 17.2~\text{s}\)) and the switched off (\(t > 17.2~\text{s}\)) thruster, respectively