A PID backstepping controller for two-wheeled self-balancing robot

This paper presents a method to design and control a two-wheeled self-balancing robot and it focus on hardware description, signal processing, discrete Kalman filter algorithm, system modelling and PID backstepping controller design. In the system, signals from angle sensors are filtered by a discrete Kalman filter before being fed to the PID backstepping controller. The objectives of the proposed controller are to stabilize the robot while try to keep the motion of robot to track a reference signal. The proposed PID backstepping controller has three control loops, in which the first loop uses a backstepping controller to maintain the robot at equilibrium, the second loop uses a PD controller to control the position of robot and the last uses a PI controller to control the motion direction. Simulations and experimental results show that the proposed control system has good performances in terms of quick response, good balance, stability .