Static and Modal Performances of Kenaf Fiber-reinforced Epoxy Composites for FPV Drone Structures

Abstract

Static and modal performances of kenaf fiber reinforced epoxy composites and their hybrid laminates were numerically evaluated for first-person view (FPV) drones. Seven laminate configurations were investigated, including full kenaf, carbon, and glass fiber composites, as well as kenaf–carbon and kenaf–glass hybrid systems with varying ply placements. Each ply contained a fiber weight fraction of ~30 wt.%. Finite element-based static structural and modal analyses were performed. Static analysis under realistic hover-loading conditions showed that the fully kenaf/epoxy frame exhibited a maximum von Mises stress of 1.20 MPa and a maximum displacement of 0.00352 mm, remaining well within safe structural limits while achieving the lowest mass (570 g). The carbon-skinned kenaf hybrid (C/K/K/C) reduced maximum stress and displacement by approximately 63% and 81%, respectively, compared to the full kenaf laminate, while maintaining a ~5% lower mass than the full carbon frame. Modal analysis revealed that the fundamental natural frequency increased from 11.9 Hz for the kenaf laminate to 13.6 Hz for the carbon–kenaf hybrid, approaching the carbon/epoxy frame value of 15.2 Hz. All kenaf-based and hybrid configurations exhibited natural frequencies well above dominant motor excitation ranges, indicating low resonance risk during FPV operation.