Design and implementation of a low-complexity flight controller for a quadrotor UAV

Quadrotors are widely used in various missions, and designing a flight controller is one of the challenges in the research field. In order to solve this problem, this paper presents an implementation of a low-complexity flight controller for quadrotors. It is performed by implementing a light controller on the Arduino Due board. The main novelty of this practical implementation is designing a cascade proportional-integral-derivative (PID) control strategy that deals with external disturbances effectively. In addition, the quadrotor's altitude is regulated using a single-stack PID controller. The paper also describes the controllers' tuning process. Precise orientation feedback is provided by employing an attitude measure system based on the extended Kalman filter (EKF). The lack of direct vertical velocity measurement is addressed using a steady-state Kalman filter (KF). Sensor calibration is performed to obtain more accurate measurements. A low-pass and a moving average filter (MAF) are also used to reduce the vibration effects caused by high-rotating rotors on the accelerometer. The flight controller framework is successfully implemented on a quadrotor prototype, and the performance of control and estimation strategies is validated using simulations and experimental flight tests. The results show that the overall system stability and performance are desirable.