Nonlinear PID controllers improved based on the quad rotor aircraft

Although linear controllers designed for the quad rotor aircraft have the obvious advantage of design information and availability of tools for control design relating to robot applications. However, due to trend of escalating performance, increasing maneuverability, unpredictable changes in environment, stronger dynamic coupling and nonlinearities necessitate more sophisticated control systems. The nonlinear controllers are designed for tracking and stabilization of the quad rotor aircraft. Design geometric nonlinear control methods, integral backstepping control, and affine nonlinear controllers based on PID controllers for the quad rotor aircraft. The improved algorithm for quad rotor aircraft has been optimized in terms of overshoot and adjustment time. The overshoot has been reduced by an average of about 15 %, and the adjustment time is also relatively short. The pitch, roll, and yaw angles tend to stabilize around 2 seconds with minimal fluctuations.