Micro air vehicle (MAV) is highly focused by many researchers because the MAV can investigate the condition of disaster site and accident site that is difficult to investigate for human being. Usually, design of the aircraft wing is inspired by birds and flying insects. Resently, dragonfly is a good research target because the dragonfly has high flight performances and high robustness. In order to develop the MAV that is inspired by the dragonfly, it is important to investigate the aerodynamic characteristics of micro structures on the dragonfly’s wing. The cross section of the dragonfly’s wing is corrugated. The effect of the corrugated shape is already investigated and applied to windmills for weak wind. On the other hand, the effect of micro spikes on the dragonfly’s wing is not investigated in spite that the number of the spikes are more than three thusands. So, we focus on the micro spikes on the wing vein of dragonfly. Firstly, we prepared the handmade artificial wings with micro spikes. The fabricated artificial wing had 150 micro spikes whose length wass 600~700 μm. We investigated the aerodynamic characteristics of the micro spikes on these artificial wings. Some merits of micro spikes were observed in spite that the length and the number of spikes were different from those of the natural wing. So, we challenged to fabricate highly realistic artificial wing and investigate the aerodynamic characteristics of the wing. A metal mold with micro holes was fabricated by the electrical discharge machining (EDM) process. Melted chitosan was applied on the mold and spread into the hole of the mold. After the solidification of chitosan, artificial wing with 400 micro spikes was fabricated. These wings had 400 micro spikes whose height is 100 μm.
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