基于累积线性法某全复材结构无人机减重设计的实现

Realization for Weight Reduction Design of an All Composite Structure UAV Based on Accumulated Linearity Method

为了研究几何大变形悬臂结构响应问题,首先,本文从理论上提出累积线性法来对这类问题进行结构建模与求解策略的探讨。理论推导与数值计算过程表明:累积线性法既合理又可行,而一次线性法的结果存在不可信等问题;从方法流程上显示,本方法在常规有限元软件平台上十分容易实现,并具有6个明显优点,这便于开展对复杂的柔性结构进行分析,使得运用累积线性法研究柔性机翼的结构响应成为可能。其次,通过比较一次总加载线性模型和不同累积次数的累积线性模型的结果,再次得出一次线性法的误差不可接受,针对此类问题,还提供了累积次数与精度的关系,即累积4次以上,便可达到工程精度要求。由此得出,累积线性法分析柔性机翼结构不仅可行,而且有效。最后,开展了某超轻型无人机全复材结构减重设计,取得了良好的效果。

In order to study the problem of cantilever structural response with geometric large de- formation, the accumulated linearity method （ALM） was proposed to deal with the structural model- ing and the solution about the preceding issue. Theoretical derivation and numerical computation indi- cated that the ALM was both reasonable and feasible, but the results by one time linearity （OTL） were incredible. The above approach and flowchart displayed that it was easy to realize on the con- ventional FEM software and owned six obvious advantages. The characteristics of this method were convenient for complex structure analysis and this made it possible to study a flexible wing structure design. Comparing the results by OTL and ALM with different times,it was indicated again that the error by OTL was unacceptable. For such a problem, the relation between accumulated times and ac- curacy was provided, which meant four-time of accumulation could satisfy the engineering require-ment. Therefore it was shown that the ALM analysis of a flexible wing structure were feasible and ef- fective. Finally, an all composite structural weight reduction design for a light-weight UAV was de- veloped successfully.