Aero-structural evaluation of kraft paper-reinforced composites for the manufacturing of UAV fuselages and wings using a numerical approach

Abstract

Contemporary unmanned aerial vehicle (UAV) manufacturing methods are based on the use of composite materials for the fuselage, wings, and other structural components. Most of these methods rely on the use of carbon fiber in the form of foam or honeycomb core composites, or carbon fiber reinforced polymers. However, the high cost and limited accessibility of carbon fiber in certain regions hinder the advancement of aerospace research, development, and marketability in said localities, which could greatly benefit from the use of UAVs in different key areas such as precision agriculture, wildlife monitoring, and disaster management. This work evaluates a low cost, easily accessible, eco-friendly material that could serve as an alternative to carbon fiber as a reinforcement material in the outer panel composites used for UAV manufacturing. The composite material, which consists of Kraft paper laminates embedded in an epoxy resin matrix, was evaluated following standard test methods for tensile and flexural strength determination. The mechanical properties obtained from these tests were used to perform numerical analyses using a fluid–structure interaction framework simulating different operational conditions of a UAV wing. Through numerical simulation, the material was tested for different structural systems (foam core and semi-monocoque) to assess its performance as a construction material. The results show that, despite having a considerable difference in strength-to-weight ratios when compared to carbon fiber composites, Kraft-paper reinforced composites are able to perform well in missions of moderate structural demand.