Planetary rover mobility simulation on soft and uneven terrain

Abstract

Rovers on Mars or the Moon for planetary exploration are obtaining increased importance within the spaceflight nations. To achieve full mission success, drivability and mobility in all kinds of complex motion scenarios have to be guaranteed. Here, proper modelling and understanding of the complex wheel–soil interaction, i.e. the terramechanics for flexible and rigid wheels interacting with hard, soft and loose soil, are a major driver for supporting reliable rover design and assisting in testing of the flight model. This paper deals with the terramechanical characteristics for wheel–soil contact dynamics modelling and simulation and its experimental validation on the basis of the future European Mars rover mission ExoMars. The physical contact models are integrated by a multi-body system approach and the performance of the rover mobility will be shown for various driving scenarios on hard and soft soil.

Keywords:

• multi-body dynamics
• terramechanics
• planetary rover
• polygon contact model
• soft soil contact model
• validation

Acknowledgements

Part of the work presented here has been performed for the ESA ExoMars chassis and locomotion subsystem development under ESA's Aurora program. The authors are most grateful to the support of the experimental testing engineers from ETH Zurich, Oerlikon Space and DLR's Institute of Space Systems without whose help the success of the verification and validation part would not be possible to the extent described herein.