A design study of a microthrust balance for space applications

Spacecraft drift from their desired orbit as a result of being subjected to external forces, such as gravity, atmospheric drag or solar pressure. In situ propulsion systems are employed to maintain a spacecraft in a specific orbit. Field emission electric propulsion (FEEP) has been proposed as a technique for maintaining orbits to very high precision for applications such as the measurement of the effects of gravitational waves. The specification of the FEEP thrusters is very demanding and they require calibration over a range of 1- to an accuracy of in the frequency range of 0.1 to 10 Hz. A design study has been completed of two balances, one with a real pivot and the other with a virtual pivot, for calibrating FEEP thrusters.