Automatic PID tuning via differential evolution for quadrotor UAVs trajectory tracking

In this paper, a two-stage automatic proportional-integral-derivative (PID) tuning scheme based on the differential evolution (DE) algorithm is developed for the trajectory tracking control of quadrotor unmanned aerial vehicles (UAVs). Nonlinear dynamics model of the quadrotor is established, based on which the tuning scheme is conducted. In the first stage, the inner loop attitude PD controllers are tuned separately with respect to the roll, pitch and yaw channel to achieve a fast transient response. In the second stage, the outer loop position PID controllers are tuned upon the optimal attitude controllers to achieve a smooth and precise trajectory tracking performance. In order to deal with coupled dynamics between the x/y channel and the altitude channel, time domain performance indexes of x/y and altitude channels are both incorporated in the cost function to be minimized. An adaptive mutation operator is utilized in the DE algorithm to maintain the population diversity in the early phase of the algorithm and accelerate convergence in the later phase. Several maneuverings including take-off, smooth translation, circular and spiral climb motions are carried out to evaluate the effectiveness of the proposed scheme.