Heat trails as short-lived navigational markers for mobile robots

Robots for nonindustrial tasks must function in less organised and predictable environments than industrial ones. This paper describes a technique for assisting mobile robots to navigate in the home and outlines progress towards a practical system. The technique involves laying and detecting trails on the ground. Of particular interest are trails which disperse after use and therefore do not require removal and do not interfere with trails laid later. These techniques are termed short-lived navigational markers (SLNM). Trails of heat are considered. Proposed applications include marking of areas already painted, searched etc., retracing a path to the starting point, and following another robot (making a train). A simple mobile robot has been designed as a test bed for heat trail laying and detection experiments. It is small and inexpensive and therefore suited to experiments involving a number of interacting robots. Heat sensors and applicators are described, together with results