Development of a rough terrain mobile robot with multistage tracks

A tracked vehicle with sub-tracks has high mobility on rough terrain. In this study, the authors have developed a tracked mobile robot which consists of two main-tracks and six and more sub-tracks in order to increase mobility. The robot has four sub-tracks at each end of main-tracks and additional multistage sub-tracks which have a unit structure at the end of the sub-tracks. The unit mechanism enables to extend to the structure of multistage tracks easily. Since the end sub-tracks can be folded, the robot is able to switch its running mode such as six-tracks mode, eight-tracks mode and so on according to the shape. This paper describes the mechanism of the robot with the unit of sub-tracks. We have developed prototypes of the robot which have eight tracks and ten tracks. Simulation and experimental results showed the step-climbing ability of this type of robot.