| Popis: |
Taking shipborne aircraft traction system as the research object, a controller based on active four wheel steering method is proposed to improve the handling stability of the system. A time-varying nonlinear dynamic model of the tractor-aircraft system on deck is established. In this model, coupling relationship between the swaying ship and the system is investigated. Extending the backstepping variable structure control theory, an active rear-wheel steering and compensative front-wheel steering control strategy is presented for the tractor. With the consideration of aircraft parameters diversity, marine environment uncertainty and the characteristics of steering subsystem, effects of the uncertainties on tractor-aircraft system stability is studied. Simulation results demonstrate that the variable structure controller can not only control the relative yaw rate between tractor and aircraft efficiently, but also enhance the navigability of traction system so that it performs well in tracking the ideal model. The ability to decrease the effects of parameter perturbation and uncertain external disturbance on system stability is improved. |
