Direct measurement of 1-mN-class thrust and 100-s-class specific impulse for a CubeSat propulsion system

Area of Science:

• Aerospace Engineering
• Space Propulsion Systems
• Miniaturized Satellite Technology

Background:

• Accurate performance characterization of CubeSat propulsion is critical for mission success.
• Existing methods may lack the precision required for micro-propulsion systems.
• Development of specialized test equipment is needed for small satellite propulsion.

Purpose of the Study:

• To develop and validate a novel thrust stand for direct measurement of thrust and specific impulse in CubeSat propulsion systems.
• To achieve high-resolution measurements of thrust and mass loss during propulsion system operation.
• To characterize the performance of a water micro-resistojet using the developed thrust stand.

Main Methods:

• Design and implementation of an inverted pendulum thrust stand with an integrated mass balance.
• Development of a calibration procedure accounting for zero-drift due to propellant consumption.
• In situ measurement of thrust, specific impulse, and mass consumption during water micro-resistojet firing tests.

Main Results:

• Achieved a thrust resolution of 80 μN and mass loss resolution of 0.01 g.
• Successfully characterized a water micro-resistojet propulsion system.
• Measured thrust ranging from 1 mN to 10 mN and specific impulse from 45 s to 100 s.
• Determined maximum measurement uncertainty of ±15.3% for the tested conditions.

Conclusions:

• The developed thrust stand enables precise, direct performance characterization of CubeSat propulsion systems.
• The system provides continuous thrust, specific impulse, and mass consumption data in a single test.
• This technology is crucial for the advancement and validation of micro-propulsion for small satellites.