Tightly coupled navigation system of a differential magnetometer system and a MEMS-IMU for Enceladus

Abstract

Targeting different sources of water hidden under thick ice shields holds the challenge to navigate towards them. In a place where most optical and radio frequency based systems are not available, alternative techniques nor navigation aiding have to be developed. One considered destination for getting samples of probably life containing water is Saturn's moon Enceladus, where some of life constitution conditions are met. In the Enceladus-Explorer (EnEx) project an automatic probe was developed, which is refined in different follow-up projects, one of them called EnEx — Magnetometer Improvement and Evaluation (EnEx-MIE). This project's main goal is to enhance the magnetometer-based navigation update algorithm developed in the former EnEx-project and to search for algorithms identifying obstacles or magnetic disturbers. This is done by investigating differential magnetic measurements. In addition to the revised magnetic part, a MEMS-Inertial Measurement Unit is used now for navigation to minimize space and power consumption of the probe, which leads to several adaptions in attitude determination algorithms. This paper focuses on the development and test of the advanced magnetic-aided navigation, magnetic calibration and reconnaissance systems inside the IceMole navigation system, which enables precise probe navigation in the ice. Furthermore it is look into the adapting of the developed algorithms to the Enceladus environment.