Controlling of Autonomous Robot Systems with Fuzzy Techniques

Abstract

This paper presents an hierarchical fuzzy control strategy of an autonomous mobile robot in unknown environments. Controlling a mobile robot in an unknown environment requires different types of reactive behaviour which can be implemented and coordinated by fuzzy rules and fuzzy sets. To combine the main tasks of mobile robot control, target steering and collision avoidance, a new hierarchical fuzzy control strategy was developed. The idea was to divide the whole control tasks in two fuzzy systems, a superior one for obstacle avoidance and a subordinated fuzzy system for target steering. This method simplifies the design of the fuzzy rules and results in a good robot behaviour in unknown environments. To locate the robot position without external sensors a mathematical model was designed, which calculates the robot path at every sample step.