Calibration methods for the simultaneous measurement of the impulse, mass loss, and average thrust of a pulsed plasma thruster.

This paper presents calibration devices and methods for the measurement of electric thruster performance parameters using a seesaw-type thrust stand to measure the mass loss of solid propellant in a vacuum. In previous studies, impact hammers and electrostatic combs have been manufactured for the calibration of the thrust and impulse using seesaw-type thrust stands. However, these conventional devices rely on self-calibration, which means that the input delivered by the device in unknown, and must undergo a calibration process themselves. In this paper, the manufactured calibration devices successfully reproduced known impulses, thrusts, and mass losses in a vacuum. By reproducing known inputs based on known masses, the proposed calibration devices can omit the conventionally required self-calibration process. The calibration results showed linear relations between outputs and known inputs and agreed with the theoretical values to within an error of 10%. Additionally, the uncertainties of all known inputs were less than 1.5%. On the basis of these results, the average thrust, impulse, and mass loss were measured using a calibrated thrust stand for the first time. The cumulative impulses obtained from the measured impulse and average thrust agreed with each other to within an error of 5%. The error of the measured mass loss per 1000 shots with respect to the actual mass loss measured using an electronic balance ranged from 1% to 17%.