Minimum-resource distributed navigation and mapping

This paper proposes a conceptual design for a distributed system of very simple robots capable of performing a useful realworld mission such as mapping the interior of a building overnight with a swarm of possibly hundreds of cockroach-sized robots. Presentation of this system concept follows an initial discussion of strategies for developing distributed robotic systems. Success is dependent on making good decisions in selecting appropriate applications, in system design, and in executing the system development process. Each robot includes basic mobility, crude odometry, contact or near-contact object/obstacle detection sensors, an omnidirectional beacon (probably IR), and a beacon detection sensor that can simultaneously detect multiple beacons on other robots and measure the bearing of each to less than one degree. Beacon triangulation (combined with knowledge of some baseline distance) allows the determination of the position of any robot (and any object next to it) relative to the others. Occlusion of a robot's beacon indicates the presence of an intervening object, while lack of occlusion identifies a “ray” of free space. Clever deployment of large numbers of robots will permit mapping of walls and objects, and can also support the detection and localization of intruders moving within the space. The object sensor can be very short range and, therefore, hopefully very simple and cheap, perhaps implemented as an array of whiskers. The beacon sensor is more complex, but it can be completely tuned to the detection of the cooperating beacon. Thus, the robots need tackle no perception tasks whatsoever. The system development begins with the implementation of an initial baseline system, in which each robot is controlled by a central coordinating element via a high bandwidth communications link. This initial effort will develop and validate behaviors and algorithms, assess sensitivity to sensor error, determine communications and processing requirements, and generally expedite the system’s evolution into a fully distributed system.