Design and Comparative Finite Element Analysis of Aluminium and Carbon Fibre Drone Chassis

Abstract

Stiffness, strength, and vibration properties are the result of the design of multirotor UAVs’ structures and thus of their flight efficiency. This is of particular importance for precision agriculture applications, where it is desirable to have very lightweight airframes that are also sufficiently stiff and damage-tolerant to counteract thrust loads and operational noise. In this work, we design and analyse a modular four-arm quadcopter frame using finite elements. A 3D frame model is developed and statically analysed in ANSYS 2025 R/2 for two different materials, namely the aluminum alloy and the carbon-fibre-reinforced polymer (CFRP). A typical hover load case (12.5 N per arm thrust, including the effect of self-weight) is also addressed under the same geometry and boundary conditions. The maximum stress concentration for both configurations is observed at the central hub. The deformation of the aluminum frame reaches a maximal value of 1.28 mm and the maximum von Mises stress is over 55 MPa, leading to a safety factor higher than four. In comparison, the CFRP frame exhibits a pair of much smaller deformations of 0.32 mm, which is around 75% improvement in stiffness with a similar stress value (∼54.6 MPa). These results validate the excellent stiffness-to-mass performance of CFRP, while aluminium should still be considered as a competitive and cheaper alternative for soft manufacturing conditions.