Applicability of Tricycle Modelling in the Simulation of Aircraft Steering System

摘要

Aircraft nose wheel steering system is simulated on MATLAB-Simulink platform to understand the influence of tyre-ground interaction and aircraft ground dynamics on the steering behaviour of the aircraft. The aircraft steering system model generally includes the Nose Landing gear model, Aircraft Dynamics model and Tyre model. In most of the literature, bicycle modelling method is adapted with two main gears lumped together and a nose landing gear, whereas tricycle modelling method with all the three gears is more appropriate and accurate way of predicting the aircraft steering response. In the present work, the mathematical formulation for the tricycle model is developed and it is observed that the resultant equations are nonlinear and coupled, whereas the bicycle model is represented with linear and coupled equations. For the same inputs parameters, both tricycle and bicycle models are simulated. Results obtained from both the models are within 5% difference with the introduction of additional non-linearity in the tricycle modelling. Hence for aircraft with nose wheel steering, bicycle method is sufficient for predicting steering response but for the all-wheel steering system (steering on both nose and main landing gear), it is more appropriate to use the tricycle modelling method to predict the accurate steering response.