Wheeled, Kinematically Redundant Locomotion System for Mobility-Oriented Research and Experimentation

Mobile robots for inspection and surveillance of hard-to-reach and hazardous areas e.g. resulting from a building collapse in the course of a natural or man-made catastrophe have to possess enhanced rough terrain mobility capabilities. First, they must be able to navigate through a given environment and to avoid insurmountable obstacles. Second, they must have the ability to traverse different forms of ground without getting immobilized by a loss of traction. Third, they must be able to negotiate a wide spectrum of obstacles including e.g. wide gaps and high steps. These abilities can be described as a mobile robots performance indices “maneuverability”, “trafficability” and “terrainability”. As a consequence, mobile robot concepts for disaster control and search-and-rescue tasks always have to be developed and evaluated with regard to these performance indices. In principle, considerable potentials with regard to mobility in unstructured and rough environments offer kinematically redundant locomotion systems equipped with powered wheels or tracks which are inspired by their biological archetype snake. These potentials are based on the systems’ snake-like; modular design as well as their given kinematic redundancy. Due to their slender, modular and flexible design the systems are basically able to travel and maneuver through noticeable narrow passes and tunnels. Further on, their kinematic redundancy can be used for a purposeful posture and terrain adaptation to safeguard traction and the system’s trafficability, respectively. Finally, the systems’ modular and articulated design, both, can be used to achieve an outstanding terrainability and to be able to negotiate remarkable obstacles. The described and expected potentials of kinematically redundant locomotion systems have to be investigated in detail as well as evaluated in practice. To be able to do so, a demonstrator has been developed and implemented for intense mobility-oriented research and experimentation. The mobile robot and first experimental results are described in the paper at hand. The system stands out especially due to an innovative sensory for slip and contact force detection.