On-going European developments in Micro Electro Mechanical Systems (MEMS) sensors sponsored significantly by the European Space Agency (ESA) offer a suitable level of performance for spacecrafts. Solid-state technology offers mechanical robustness, with low power consumption, mass and size, which are major advantages to spacecraft system design and accommodation. Those sensors are of particular interest in robotic planetary exploration as well, where traditionally large, complex and expensive sensors are difficult to accommodate having big impact to other subsystems. Miniaturized sensors though currently provide lower level of performance compared to the traditional ones. Answer the question of reliability and performance of these new sensors for space robotics applications is aiming in the context of this work.
This talk addresses the analysis and modelling of MEMS inertial sensors for rover attitude estimation in an exploration rover scenario. Characterization and modeling of inertial sensor errors using the Allan variance technique will be introduced as well as tests procedure and results. Afterwards, sensor fusion and the performance of MEMS inertial sensor in rover navigation and localization will be discussed. Attitude and Heading Reference Subsystem (AHRS) make part of a complete Inertial Navigation System; this subsystem incorporates the sensor error model and has been developed based on Unscented Kalman Filter, algebra of quaternion and Rodrigues parameters.
Experimental results of this work has been carried out on two rovers platforms for space missions using the prototype of a particular Inertial Measurement Unit based on MEMS. The ExoMars Demonstration Rover (ExoMaDeR), a half-size prototype of the coming ExoMars rover and the Lunar Rover Module (LRM), a real size flight model for lunar exploration concept, have been used in the Planetary Utilization Testbed (PUTB) of the Automation and Robotics Laboratory located in the European Space Research and Technology Centre, the largest site of the European Space Agency.