Three Dimensional Trajectory Generation for an Autonomous Plane

A 3D optimal trim trajectories planner algorithm for an autonomous plane is presented in this paper. This planner can generate a sequence of 3D elementary trajectories for a set of predefined waypoints in space. The proposed algorithm uses a sequence of five elementary trim trajectories to generate a three dimensional global trajectory in space.  The trim property reduces significantly the complexity of the dynamical model and thus the resolution of the trajectory planning and tracking problems. This approach is based on the Bang-Zero-Bang strategy, taking into account the state and inputs constraints due to the vehicle dynamics, flight envelope and the actuators limitations. In this study, we demonstrate that this strategy satisfies the necessary optimality condition of Pontryaguin.