AbstractThis paper introduces novel methods for terrain classification and characterization with a mobile robot. In the context of this paper,terrain classificationaims at associating terrains with one of a few predefined, commonly known categories, such as gravel, sand, or asphalt.Terrain characterization, on the other hand, aims at determining key parameters of the terrain that affect its ability to support vehicular traffic. Such properties are collectively called “trafficability.” The proposed terrain classification and characterization system comprises a skid‐steer mobile robot, as well as some common and some uncommon but optional onboard sensors. Using these components, our system can characterize and classify terrain in real time and during the robot's actual mission. The paper presents experimental results for both the terrain classification and characterization methods. The methods proposed in this paper can likely also be implemented on tracked robots, although we did not test this option in our work.