Fabrication of Flapping Wing Mechanism Using Various Polymer Based 3D Printing Techniques and Aerodynamic Performance Evaluation

The design of flapping wing micro aerial vehicle (FWMAV) imposes several challenges with reference to dimensional stability for micro mechanism assembly and ability to withstand cyclic loading conditions. Earlier manufacturing methods such as injection moulding and wire cut electrical discharge (EDM) machining necessitate more human efforts, time-consuming and increase cost of preparation of mould. The 3D printing (3DP) process seems to be well suited to manufacture small and intricate parts with good accuracy and reduces the labour cost. In this article, three 3DP technologies with various polymer materials such as Polyjet (Polymethyl methacrylate), Multijet (Polypropylene–light) and Stereolithography (Polypropylene Fumarate) are exploited to fabricate micromechanical linkages of FWMAV mechanism. The structural characteristics of these 3DP materials are evaluated using Finite Element Analysis. The aerodynamic performance of 3D printed mechanism assemblies is evaluated for various angle of attack at diverse wind speed conditions using the developed test rig. Wind tunnel experimental results revealed that low elastic modulus materials produced more amount of lift and high elastic modulus materials experienced less drag. These experimental results suggested that 3DP can be utilized to manufacture small batch of micro mechanism components as an alternative to injection moulding and wire cut EDM.