Quadrotors trajectory tracking using a differential flatness-quaternion based approach

A quadrotors is a type of Unmanned Aerial Vehicles (UAV) systems that attract the researchers in the control field since it's a highly nonlinear, underactuated system. In this paper, a non-linear dynamic model based on quaternions is developed. Differential flatness is an approach that enables the optimization to occur within the output space and therefore simplifies the problem of the trajectory tracking. This work aim to combine both methods in order to create a differential flatness-quaternion based approach that enables the quadrotors to follow a desired optimal path and avoid any singularities that can occur. The trajectory tracking is assured by a double loop control structure based on the LQR controller.