A Fuzzy Obstacle Avoidance Controller Using a Lookup-Table Sharing Method and Its Applications for Mobile Robots

A Lookup‐Table (LUT) based design enhances the processing speed of a fuzzy obstacle avoidance controller by reducing the operation time. Also, a LUT sharing method provides efficient ways of reducing the LUT memory size. In order to share the LUT which is used for a fuzzy obstacle avoidance controller, an idea of using a basis function is developed. As applications of the shared LUT‐based fuzzy controller, a laser‐sensor‐based fuzzy controller and an ultrasonic‐sensor‐based fuzzy controller are introduced in this paper. This paper suggests a LUT sharing method that reduces the LUT buffer size without a significant degradation of the performance. The LUT sharing method makes the buffer size independent of the fuzzy system’s complexity. A simulation using MSRDS (Microsoft Robotics Developer Studio) is used to evaluate the proposed method. To investigate the performance of the controller, experiments are carried out using a Pioneer P3‐DX with LabVIEW as an integration tool. Although the simulation and experiments show little difference between the fully valued LUT‐based method and the LUT sharing method in terms of the operation time, the LUT sharing method reduces almost 95% of the full‐valued LUT‐based buffer size.