Uncertain Modal Analysis of Unmanned Aircraft Composite Landing Gear

无人机复合材料起落架不确定性模态分析

Through taking uncertain mechanical parameters of composites into consideration,this paper carries out uncertain modal analysis for an unmanned aircraft landing gear.By describing correlated multi-dimensional mechanical parameters as a convex polyhedral model,the modal analysis problem of a composite landing gear is transferred into a linear fractional programming(LFR)eigenvalue solution problem.As a consequent,the extreme-point algorithm is proposed to estimate lower and upper bounds of eigenvalues,namely the exact results of eigenvalues can be easily obtained at the extreme-point locations of the convex polyhedral model.The simulation results show that the proposed model and algorithm can play an important role in the eigenvalue solution problem and possess valuable engineering significance.It will be a powerful and effective tool for further vibration analysis for the landing gear.

考虑复合材料力学参数的不确定性,对某无人机起落架进行模态分析研究。通过将相关多维力学参数描述为一个凸多面体模型,复合材料起落架的模态分析问题可转化为一个线性分式规划特征值求解问题,进而提出了特征值上下界的极点求解算法,即可在凸多面体的极点求得特征值的精确解。仿真结果表明,提出的模型和算法在工程结构特征值问题中具有真实的工程意义,在进一步起落架振动分析研究中可成为一种重要的强有力的计算工具。