Applied Sciences 10 17 (6044) Open Access 9/2020.
A planetary exploration rover’s ability to detect the type of supporting surface is
critical to the successful accomplishment of the planned task, especially for long-range and
long-duration missions. This paper presents a general approach to endow a robot with the ability
to sense the terrain being traversed. It relies on the estimation of motion states and physical
variables pertaining to the interaction of the vehicle with the environment. First, a comprehensive
proprioceptive feature set is investigated to evaluate the informative content and the ability to gather
terrain properties. Then, a terrain classifier is developed grounded on Support Vector Machine
(SVM) and that uses an optimal proprioceptive feature set. Following this rationale, episodes of high
slippage can be also treated as a particular terrain type and detected via a dedicated classifier. The
proposed approach is tested and demonstrated in the field using SherpaTT rover, property of DFKI
(German Research Center for Artificial Intelligence), that uses an active suspension system to adapt
to terrain unevenness.