Interval Type-2 Fuzzy and PID Dual-Mode Controller for an Autonomous Mobile Robot#

The basic feature of mobile robots is to possess obstacle avoidance and autonomous navigation capability, which are inherently two of the most difficult tasks in path planning. In this paper, an interval type-2 fuzzy logic controller (IT2FLC) is used for autonomous navigation in the presence of environmental uncertainties or internal noises. A PID controller is also integrated with the IT2FLC to increase the robustness of the controller for eliminating the control error for tracking paths with small curvatures. The dual-mode design can significantly promote the real-time performance of the autonomous navigation system and effectively eliminate system errors to reach equilibrium points faster. In our experiments, we implemented the proposed fuzzy controller for both the right and left wall following and obstacle avoidance on the P3-DX mobile robot which has eight sonar sensors. The fuzzy controller helps the mobile robot to decide which side or wall would be followed by detecting the nearest wall on each side. Experimental results are illustrated to show that the effectiveness of the proposed controller is better other controllers in avoiding obstacles and wall following.