橇式起落架动刚度及阻尼特性试验研究

Experimental Investigation on Dynamic Stiffness and Damping Characteristics of Skid Landing Gear

起落架动刚度及阻尼特性是研究直升机“地面共振”问题两个重要参数。刚进入国产化阶段的模式起落架迄今尚无可靠的理论计算方法来确定这两个参数．本试验研究利用某型直升机真实的模式起落架为试件，采用机械阻抗测量法来研究该起落架的动刚度及阻尼特性。试验使用电液伺服激振设备，对模式起落架进行不同频率的激振，实时测量相应的载荷及位移响应，从而得出了模式起落架的动刚度及阻尼。试验模拟了直升机完全停机及半升力卸载情况，在机场及冰面降落情况，以及３个不同方向的受载情况。试验结果已直接用于某型直升机的“地面共振”分析。

Dynamic stiffness and damping characteristics of landing gears are important parameters to be used to investigate the 'ground resonance' of helicopters. There is no reliable.computational method to determine these two parameters for the skid landing gear in the stage of national production.In this experimental investigation,the dynamic stiffness and damping characteristics of an actual skid landing gear on a helicopter are obtained by exciting the skid landing gear at different frequencies and measuring the responses of load and displacement in real time. The experiment simulated some cases of helicopter stop,half-lift unload and landing at airfield and icefield. The experimental results have been used directly to analyze the 'ground resonance' of a helicopter.