Optimization of air race trajectories

A novel approach for the optimization of air race trajectories that takes into account the highly non-linear nature of the dynamics of the participating aircraft is presented. For the optimization an enhanced, scalable multifidelity simulation model is utilized which is a sequential model extending the translation and position dynamics by different representations for the attitude and the rotational dynamics in the inner loop of the flight system. The scalable inner loop can either contain linear transfer functions for the load factors and the roll rate, linear state-space models for the longitudinal and the lateral motion of the aircraft or the fully non-linear rotational and attitude dynamics. With the sequential structure of the model, the complexity level of the inner loop and thus the optimization time and quality can easily be adapted to the required level. Furthermore, inversion controllers for the different loops are incorporated in the simulation model that enable the development of a procedure for the generation of robust and suitable initial guesses for the optimization with full non-linear 6-Degree-of-Freedom simulation models. The novel approach allows for the solution of highly complex trajectory optimization problems where classical methods failed mainly due to stiffness problems. The full dynamic order of the flight system considered is taken into account such that the resulting optimal race trajectory is truly achievable.