PRECISE DETERMINATION OF ACCELEROMETER PROOF MASS

摘要

The accelerometer is of high potential to be widely used in aerospace exploitation, especially the planet gravity field modeling. It can measure very accurately all non-gravitational accelerations, and also the acceleration due to the gravity gradient and the angular motion related acceleration if the proof mass of the accelerometer is not positioned at the center of mass of the spacecraft. In most application cases, the later part of acceleration is intended to be kept as small as possible. In fact, it can be removed if the proof mass can be determined, and furthermore it may be eliminated by mass balancing. By superimposing torque with short period upon the spacecraft, the accelerometer observation could fall into two parts, one can be easily fitted by linear terms, and the other will have same period as the torque. From the later part, the proof mass position can be determined by the algorithms presented in this paper. System requirements to determine the proof mass is investigated. A complete simulation is shown that the accuracy of proof mass could be determined better than 0.1 mm along each axis.