Fire brigades and other specialized agencies are often required to undertake extremely dangerous search and rescue operations in which it is important first to verify the safety of the environment and then to obtain clear remote images of the inside of buildings and underground areas. Several studies have addressed the possibility of using robotic tools to make such operations safer for operators and more efficient in time and resource allocations. This paper describes the development of the HELIOS team, consisting of five tracked urban search and rescue robots. Two of these have arms and grippers for specialized tasks, such as handling objects and opening doors. The other three use cameras and laser range finders to construct virtual 3D maps of environment explored, moving autonomously while collecting data using a Cooperative Positioning System (CPS). After introducing robot team specifications, we detail mechanical robot design and control systems. We then present test results for the CPS and HELIOS IX vehicle together with typical mission experiments.
