Control of a Four-Wheeled Mobile Robot Using Fuzzy Logic Controller

This paper introduces a fuzzy controller designed for goal-directed navigation of a differentially driven four—wheeled mobile robot in indoor environments. The controller calculates motor voltages from two key inputs—turning angle and distance to the target—allowing the robot to optimize motor performance, accelerating for efficiency when distant and decelerating for precision as it approaches the target. A critical challenge in this design is the accurate definition of fuzzy rules and voltage ranges for smooth and controlled turning, ensuring maximum stability and precision in movement. This design approach, focused on voltage control instead of direct speed and torque input, makes it highly relevant for real-world applications, including aiding in the development of autonomous vehicle systems. Compared to a conventional Proportional Integral Derivative (PID) controller and a simple fuzzy controller, the fuzzy controller demonstrates superior trajectory tracking and reduced tracking errors, with only a marginal increase in runtime. This adaptive method effectively handles nonlinearities, significantly enhancing the robot's robustness and accuracy in complex, uncertain situations.