水陆两栖飞机高支柱起落架的刹车振动行为

The heading vibration of a certain type of high strut landing gear of amphibious aircraft is studied during the aircraft braking and sliding. A multi-body dynamics model of gear vibration is first established. The results of the modal test, drop test and static test are used to fully verify the modal, cushioning performance and stiffness performance of the landing gear, which show good agreement with the simulation results, thus obtaining the rigid-flexible coupling accurate model for gear heading vibration analysis. The model of the brake control system is then introduced to study the whole process of the landing gear vibration response from landing to braking and then to grounding. The braking efficiency and gear vibration characteristics of the constant braking torque, the speed difference PBM brake control system and the slip rate PID brake control system are compared. The results show that the wheel will lock when the braking torque amplitude exceeds 23. 4 kN · m. Compared with the pressure-bias-modulated brake control system, the braking distance and braking time of the PID brake control system are reduced by 19.17% and 25.45%, respectively. However, the initial vibration of the wheel axle is relatively large under the action of the PID brake control system. Adjusting the slope of the initial slip rate to the optimum slip rate reduces the maximum amplitude of the wheel axle longitudinal displacement by 31.24% . Finally, to study the stability of the two kinds of brake systems, we add abrupt signal variation to the wheel speed sensor module. The results reveal that the PBM brake control system causes brake failure, while the PID brake control system can quickly recover, showing strong anti-disturbance ability.