Structural Optimization of the Landing Gear of a Mini-UAV

Abstract

The main purpose of this study is to determine the opti mum geometry and material for the main landing gear of a mini -UAV. The optimization is achieved by using numerical methods and the results are experimentally validated. Numerical studies are based on the finite element analysis of the landing gear. Landing gears of UAV’s may be subjected to both static and dynamic loads. Therefore, all load cases should be taken into account during the design. However, because the most critical load case is the impact during the landing, the impact load is also considered i n this study. The impact of landing gear on ground during landing is modeled using ANSYS finite element software. The landing gear is discretized using the layered shell elements. Numerical solutions are obtained for several types of laminate configuration s, materials and geometries. An optimum shape, material and laminate configuration are determined as a result of the finite element analyses results. Experimental studies followed the numerical studies. A landing gear, which is chosen from feasible designs obtained by using the finite element analyses results, is manufactured using composite materials, then, it is tested under a static load . The numerical and experimental results are compared and the best design is selected. Nomenclature E = Young’s modulus G = shear modulus � = Poisson’s ratio �* = tensile strength �* = fracture strain �A = stress at region A �B = stress at region B �A = strain at region A �B = strain at region B U = displacement Pcr = critical buckling load F = applied load µS = microstrai n t = thickness of the laminate