Simple controller for trajectory tracking control of quadrotor unmanned aerial vehicle

Abstract

In this paper, a simple trajectory tracking controller for the quadcopter is considered. A quadcopter has a good maneuverability, so it can be easily controlled by the wireless controller as far as it stays within the field of vision. If we need to control the quadcopter in wide range, like a trajectory tracking control, some controller that guarantees the stability of the closed loop should be designed and implemented. The quadcopter is a nonlinear system, so, it is not necessarily simple to design such a controller. In general, PID controller is very simple and it works well, but, the stability analysis is not enough. In this paper, a controller based on a linear approximate model around a desired trajectory is considered. Such an approximate model is usually a linear time varying system, and, in general, some time varying controller is needed. Here, by limiting the desired trajectory to the simple and practical class, a linear time invariant approximate model can be obtained. Using this model, linear time invariant fixed controller that stabilizes the approximate model is obtained for all desired trajectory in such a limited class. This is a simple and fixed trajectory tracking controller for quadcopters so that the closed loop system is stable around some desired trajectory class. Some simulation results are also shown.