Development of light weight multi-rotor UAV structures through synergistic application of design analysis and fused deposition modelling

Additive manufacturing (AM) technologies are gaining acceptance for fabricating end-use parts in several sectors and this study focuses on developing AM-based approach for gainful development of unmanned aerial vehicles (UAVs). Design-freedom and time-compression are synonymous with AM technologies and to realise the same in the development of UAVs, redesigning of the components is imperative. This paper presents a protocol that synergistically combines design iterations and fused deposition modelling (FDM) for developing light-weight structures for multi-rotor UAVs. Rather than employing expensive industry-grade FDM systems, the present study illustrates a fabrication protocol based on desktop 3D printers and affordable FDM filament material of polyactic acid (PLA). Multiple design configurations are analysed and prototyped leading to considerable weight reduction. The resultant operational benefits that are related to lesser part count, lower assembly effort and higher flight duration as compared to the conventional designs are demonstrated through experimental efforts. A customised process for electrochemical deposition of copper-nickel layers over the PLA parts is developed for enhancement in tensile, flexural and impact performance. Findings from this study lead to new vistas for rapid design iterations through an AM centric fabrication process with consequential impact on ever burgeoning UAV domain.