Experimental Characterization of Materials for Structural Airframe Elements of a Multirotor UAV  

Petar Piljek, Denis Kotarski, Zdenka Keran and Matija Krznar

DOI: https://doi.org/10.64486/m.65.2.7
Online publication date: November 29, 2025

Abstract: This work presents a cost-efficient experimental framework for characterizing structural materials used in rotor arms of multirotor UAVs. A set of specimens, including FDM-printed PLA and PETG with varying wall thicknesses and infill percentages, and CFF-printed Onyx reinforced with fiberglass, was evaluated against a commercially established reference (S500). Static deflection tests revealed that increasing the wall number and infill in PETG specimens reduces deflection at the expense of mass, with the selected PETG design achieving ~30 % lower de-flection and ~20 % lower mass than the commercial airframe. CFF specimens showed superior stiffness but were considerably more expensive and required significantly longer production times. The study demonstrates that low cost experimental testing provides useful mechanical data, supporting the design of lighter, structurally efficient rotor arms.

Keywords: multirotor UAV; rotor arm; additive manufacturing, experimental characterization

This article is published online first and will appear in Metalurgija, Vol. 65, Issue 2 (2026).