Recent Review Paper from Advances in Mechanics——Relative measurement for the proof mass flying along a purely gravitational orbit

Journal Tittle: Advances in Mechanics

Tittle: Relative measurement for the proof mass flying along a purely gravitational orbit

Author: Zhendong HOU1, Zhaokui WANG2, Yulin ZHANG1,2

Affiliation: 

1 Research Center of Satellite Technology, Harbin Institute of Technology, Harbin 150080, China;
2 School of Aerospace, Tsinghua University, Beijing 100084, China

Abstract:

Purely gravitational orbits are the trajectories of objects in space with grav-itational force only. Once constructed, they allow us to detect spaceborne gravity with extremely high precision, and provide highly stable spacecraft platforms for scientific ex-periments. As the core of purely gravitational orbit construction, the relative measurement for the proof mass is used for scientific data acquisition, and spacecraft tracking control input. In this paper, we first present the concept of purely gravitational orbits, and sum-marize the applications on satellite gravity measurement and gravitational wave detection. Then we survey the relative measurement requirements for various missions, and give the principles, pros and cons for three major measurement methods, namely, capacitive sensing, magnetic sensing and optical sensing. According to the attitude motion of the proof mass, the relative state resolving for its mass center can be classified into three categories. We investigate the typical resolving models based on attitude dynamics and surface modeling of the proof mass, and the velocity estimation methods for mass center. Finally we discuss the-oretical computations, on-ground validations and on-orbit validations for non-gravitational disturbances.

Keywords:  spaceborne gravity detection; purely gravitational orbit; relative measurement; relative state resolving; non-gravitational disturbance