AOCS for future multi-satellite geodesy missions

Abstract

Missions like GRACE and GRACE-FO have successfully established a continuous time series of data for Earth gravity field estimation. The continuous observation of Earths gravitational field is essential for the understanding of Earths mass transportation and climate change. Since GRACE-FO is already in service and the demand of more accurate data series arises, new Mission concepts need to be investigated to guarantee the continuation of the data time series and to increase the accuracy of Earths gravity field estimation. The German Aerospace Center (DLR) Institute for Satellite Geodesy and Inertial Sensing and the ZARM, University of Bremen are developing a Multi-Purpose Space Mission Simulator in the scope of the DFG Collaborative Research Center 1464 TerraQ. The simulation platform is capable of modelling for the atmospheric, magnetic, radiative, and gravitational environment in orbit and their coupling into system and sensor-specific effects. This work focuses on extending the simulation environment with an attitude control system to investigate next-generation gravimetry mission (NGGM) concepts with multiple satellites. The attitude control system should be modeled in three parts: Sensors, State Estimator and Controller, and Actuators. The aim is to model a realistic attitude control system. Thus, the performance of different satellite constellation approaches, such as pendulum orbits, bender orbits, and swarm constellations can be examined with the help of the simulator. Requirements for the AOCS subsystem will be derived to evaluate the feasibility of such mission concepts and sensors. This paper presents the current status of the research.