Accounting for limited sensing in real-time obstacle avoidance for mobile robots

Obstacle detection is a critical task in mobile robot navigation. To allow for rapid reactions to changes in the environment, it is required to complete its operation in short time intervals. That can be difficult if computing and/or sensing robot resources are limited. Therefore, it is important to design precisely what sensorial information will be needed to guarantee detection, and how it will be gathered to guarantee throughput. In this paper we present analysis and experiments related to the design of an obstacle detection system for a mobile robot with limited sensing capabilities. Objectives are to preserve safety while maintaining good motion performance. The design is made in two steps. Firstly, to find what is the minimum information needed to assure safety as a function of the sensors at hand, the robot capabilities and the intended motion control policy. Second, to manage the available sensors in order to provide the required information when needed. For the example studied, a justified solution has been defined which guarantees detection, robot safety, and good motion performance in real time. The solution has been tested with experiments that illustrate the effectivity achieved.