Design and implementation of a PID control system for a coaxial two-wheeled mobile robot

This paper presents the design of a control system for a coaxial two-wheeled inverted pendulum robot. The control strategy implemented was developed based on a dynamic model of the robot that takes into consideration its three degrees of freedom, and consists of two decoupled PID controllers, tuned by Ziegler-Nichols technique. Such strategy is responsible for controlling the robot´s pitch motion and linear positioning regardless of its yaw motion, ensuring system stability, proper set-points tracking and disturbances rejection.