During a volcanic activity, it is very dangerous to approach a restricted area. For this reason, robotic remote observation system would be quite useful, and it is particularly urgent for a country with a high degree of volcanic activity, such as Japan. In response to this need, our research group developed a novel multi-D.O.F. tracked vehicle, called ELF, which can conduct observation in a restricted volcanic area. The robot essentially consists of six tracks, and it has eleven actuators that change its configuration. These actuators enable the robot to assume various configurations, which increase its ability to traverse weak and rough terrains in the area around a volcano. In this research, we propose one configuration of the robot, in which the surface of the contact plane at the bottom of the track is horizontal, which is advantageous for traversing a weak slope. The feasibility of this design was verified in a field experiment on Mt. Kushigata, on the island of Izu-Oshima, and in a simulated volcanic field that was filled with pumice stones.