The shimmy vibration is among the causes of reduction of the nose landing gear (NLG) fatigue life. Usually, the shimmy vibration problem is mitigated by installing passive dampers on the NLG, however, both semi-active and active shimmy suppression systems are currently investigated looking for better damping performance. The present work presents the design and numerical investigation of an active shimmy suppression system based on the simple adaptive control technique. Despite of the good results obtained during the design of the controller, it is to be taken into account that the controller designed for the nominal system may not be optimal for the actual working condition. For instance, environmental conditions influence the tire-road interaction while systems failures or wear can reduce the NLG stiffness and damping properties, moreover the taxiing speed and the system weight are varying parameters as well. The ultimate goal of the present work is the performance robustness analysis of the proposed simple adaptive shimmy suppression system under parameters uncertainties by means of Stochastic Robustness Analysis.
A STOCHASTIC ROBUSTNESS VERIFICATION OF NLG SIMPLE ADAPTIVE SHIMMY SUPPRESSION SYSTEM
Alaimo A.;Orlando C.
2021-01-01
Abstract
The shimmy vibration is among the causes of reduction of the nose landing gear (NLG) fatigue life. Usually, the shimmy vibration problem is mitigated by installing passive dampers on the NLG, however, both semi-active and active shimmy suppression systems are currently investigated looking for better damping performance. The present work presents the design and numerical investigation of an active shimmy suppression system based on the simple adaptive control technique. Despite of the good results obtained during the design of the controller, it is to be taken into account that the controller designed for the nominal system may not be optimal for the actual working condition. For instance, environmental conditions influence the tire-road interaction while systems failures or wear can reduce the NLG stiffness and damping properties, moreover the taxiing speed and the system weight are varying parameters as well. The ultimate goal of the present work is the performance robustness analysis of the proposed simple adaptive shimmy suppression system under parameters uncertainties by means of Stochastic Robustness Analysis.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
