Design and Testing of a Double-Sided Ion Thruster for Ion-Beam Shepherd

Abstract

The ion-beam shepherd (IBS) space debris removal method requires two thrusters: one for impulse transfer (IT) and one for impulse compensation (IC). This paper proposes a novel thruster concept for the IBS-type missions where a single double-sided thruster (DST) simultaneously producing ion beams for the IT and IC purposes is used. The advantage of the DST design is that it requires approximately half the radio-frequency power compared with two single-ended thrusters, and it has a much simpler subsystem architecture, lower cost, and lower total mass. Such a DST thruster was designed, built, and tested. During the experimental campaign, a successful extraction of two ion beams from a single discharge chamber was achieved. The paper shows that it is possible to control the thrust magnitudes from the IT and IC thruster sides by altering screen/accel grid voltages, radio-frequency generator power, and mass flow rate. This is achieved by designing the IT and IC ion optics geometries to be different. It is demonstrated that the IC side can produce 30% more thrust compared with the IT side, proving that the DST concept is a viable alternative for the IBS-type space debris removal missions.