At the University of Alabama in Huritsville's Propulsion Research Center a new magnetically levitating low-friction test stand was designed and built for the purpose of ground testing micro-propulsion devices. The overall objective was measure the performance characteristics of micro-thrusters, such as impulse-bit and specific impulse, through a series of individual firings. The test stand utilized a magnetic levitation controller to suspend a payload containing the necessary firing and data collection electronics. This concept was based on the basic fundamentals published in the literature for the torsional thrust balance micro-thruster test stand configuration. Upon firing, the levitating payload rotated and the lateral acceleration and angular velocity data were collected using accelerometers and a gyroscope. Sensor calibration experiments, performed with a high speed camera, verified proper function of the gyroscopic sensor. The test stand was able to capture impulse-bit with milli-Newton-second resolution. Uncertainty for impulse-bit measurements generally ranged from 6.8% - 8.1% and specific impulse uncertainty ranged from 10% - 23%.
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