REPUBLIC OF SERBIA

MINISTRY OF DEFENCE

www.mod.gov.rs

MINISTRY OF DEFENCE

Material Resources Sector

Defensive Technologies Department

Military Technical Institute

www.vti.mod.gov.rs

STRENGTH ANALYSIS OF MAIN LANDING GEAR TYPE LAYERED COMPOSITE LEAF SPRING FOR UNMANNED AERIAL VEHICLE

IVANA ILIĆ

Military Technical Institute, Belgrade

SRĐA PERKOVIĆ

Military Technical Institute, Belgrade

DRAGAN ILIĆ

Military Technical Institute, Belgrade

MARKO BOJANIC

Military Technical Institute, Belgrade

Abstract: : This paper considers some aspects of design of composite leaf spring made of composite materials (combining glass fiber reinforced polymer and CFC layered parts). A special attention in this investigation is focused on strength and stiffnes analysis of unmanned aerial vechicle (UAV). Finite Element Analysis (FEA) predictions of load-deflection curves under static loading are presented, together with test results. Main consideration was given to the optimisation of the leaf spring geometry. The objective was to obtain a leaf spring with minimum weight that is capable of carrying given static external forces by constraining limiting stresses and displacements. The finite element results using MSC/NASTRAN software code showing stresses and displacement were verified with experimental results. For such purpose layered shell finite elements are used. Good compatibility of numerical data to  experimental results is obtained.

Keywords: unmanned aerial vechicle, composite leaf spring, finite element analysis, displacements.