Determining liquid fill fraction on a spacecraft

摘要

A method and apparatus of determining the fill fraction of a liquid in a spacecraft in weightless space is disclosed. A small motion is introduced about the center of mass of the spacecraft undergoing steady spin and/or thrust, and resulting spacecraft oscillations are sensed. The measured frequency, amplitude and phase of the spacecraft oscillations are compared with counterpart values predicted for possible liquid quantities by a nonempirically computed model of spacecraft dynamics.