Controlled balance losing in random step environment for path planning of a teleoperated crawler-type vehicle

Rescue robotics is the application of robotics to the search and rescue domaaimed at extending the capabilities and increasing the safety of the rescuers. Deployed on a site during a rescue mission, a mobile robot is teleoperated by a human operator from a safe place. To suggest to the operator a good direction to traverse the three-dimensional (3D) debris environment, we develop a pilot system, which requires a special path search algorithm on debris and a proper definition of a search tree. Although the main goal of the algorithm is to keep the robot maximally stable at every step of its path, in some cases we need the robot to change a 3D orientation discontinuously through losing its balance. Losing balance on purpose is an essential feature for safe climbing up and going down debris, and it is the central issue of this paper. Exhaustive simulations were used to structure and analyze data. Experiments with a real robot verified our approach to removing unsuitable search directions from the search tree and gave important feedback to the algorithm.