直升机脚蹬异常低频振动分析

Analysis of Abnormal Low-Frequency Vibration of a Helicopter Pedal

针对一次直升机空中脚蹬异常低频振动故障,利用频率分析、滤波分析等方法对飞行振动数据进行分析;基于飞行振动实测数据和尾操纵拉杆固有频率测试数据建立了集中质量模型,计算分析了尾操纵杆系的动力学特性以及对于不同频率振动的传递特性;确定了该起脚蹬异常低频振动的原因,揭示了脚蹬振动的来源;得到了尾操纵杆系对于不同频率振动的传递特性;依据计算分析结果提出了相应的解决方案。试飞验证表明改进措施有效,为后续类似问题提供了解决思路。

In order to analyze and solve the problem of abnormal low-frequency pedal vibration of the helicopter in flight,in this paper an analysis of this vibration was conducted.Flight vibration date analysis methods such as FFT and digital signal filtering were used to reveal the features of abnormal low-frequency pedal vibration.Then,based on the flight vibration measured data and the natural frequency test data of tail control rods,a lumped mass model was established to calculate and analyze dynamic characteristics and different frequencies vibration transmission characteristics of the tail control rod system,determined the causes of abnormal low-frequency pedal vibration,revealed the source of pedal vibration,obtained the transmission characteristics of tail control rod system for different frequencies vibration.Based on the analysis results,solution methods were putted forward.Through flight test,it showed that that the solution methods were effective and provides solutions for similar problems in the future.