This paper aims to present a concept of an automatic directional control system of remotely piloted aerial system (RPAS) during the taxiing phase. In particular, it shows the initial stages of the control laws synthesis – mathematical model and simulation of taxiing aircraft. Several reasons have emerged in recent years that make the automation of taxiing an important design challenge including decreased safety, performance and pilot workload.
The adapted methodology follows the model-based design approach in which the control system and the aircraft are mathematically modelled to allow control laws synthesis. The computer simulations are carried out to analyse the model behaviour.
Chosen methodology and modelling technique, especially tire-ground contact model, resulted in a taxing aircraft model that can be used for directional control law synthesis. Aerodynamic forces and moments were identified in the wind tunnel tests for the full range of the slip angle. Simulations allowed to compute the critical speeds for different taxiway conditions in a 90° turn.
The results can be used for the taxi directional control law synthesis and simulation of the control system. The computed critical speeds can be treated as safety limits.
The taxi directional control system has not been introduced to the RPAS yet. Therefore, the model of taxiing aircraft including aerodynamic characteristics for the full range of the slip angle has a big value in the process of design and implementation of the future auto taxi systems. Moreover, computed speed safety limits can be used by designers and standard creators.
