A thrust balance for low power hollow cathode thrusters

Hollow Cathode and Low-Thrust Extraction Grid Analysis for a Miniature Ion Thruster

Miniature ion thrusters are well suited for future space missions that require high efficiency, precision thrust, and low contamination in the mN to sub-mN range. JPL’s miniature xenon Ion (MiXI) thruster has demonstrated an efficient discharge and ion extraction grid assembly using filament cathodes and the internal conduction (IC) cathode. JPL is currently preparing to incorporate a miniature...

An Inverted-Pendulum Thrust Stand for High-Power Electric Thrusters∗

The inverted-pendulum method of thrust measurement for high-power electric thrusters is described analytically and experimentally. Two sources of uncertainty in the thrust measurements are investigated: those due to changes in the sensitivity of the inverted pendulum and those due to tare forces resulting from thermal stresses and electromagnetic forces acting on the flexural elements. An ideal...

Low-Current Hollow Cathode Evaluation

An experimental investigation of the operating characteristics of 3.2 mm diameter orificed hollow cathodes was conducted to examine low-current and low flow rate operation. Cathode power was minimized with low orifice aspect ratio and the use of an enclosed keeper. Cathode flow rate requirements were proportional to orifice diameter and the inverse of the orifice length. Cathode temperature pro...

Transition characteristics of low-pressure discharges in a hollow cathode

An Evaluation of Hollow Cathode Scaling to Very Low Power and Flow Rate

As Hall and ion thrusters are scaled to power levels below 300 W to operate on smalland micro-satellites, hollow cathodes must be designed to accommodate the new operating regimes with efficient use of power and propellant. The conclusions of previous cathode scaling efforts by other authors are reviewed, and the importance of heat transfer and orifice processes are emphasized. Performance data...