Dynamic Behaviors of Butterfly Wing and Their Application to Micro Flight Robot

Micro-Air-Vehicle (MAV) and micro-flight robot using insect and bird flight mechanisms has been attracting significant attention in recent years since the micro-electromechanical systems (MEMS) have been developed actively. Many researchers have attempted to develop MAV and micro-flight robot with various actuators and devices so far however their studies have not led to practical applications yet. One of the reasons is that flying mechanism of birds and insects has not been clarified sufficiently. In this study, we evaluate dynamic behaviors of a wing observed from the butterfly’s viewpoint in its flight. The authors conduct a flight observation experiment of Cynthia cardui performing a free flight and fixed flight and an image analysis and calculate flapping angles, lead-lag angle and feathering angles of the butterfly performing flapping flight to clarify the relation between them. Furthermore, we aim at developing the micro flight robot like the butterfly using these results. The butterfly realizes its flapping motions by changing not only flapping angles but also lead-lag angles in free and fixed flights. In a free flight, a butterfly performs flapping by greatly changing feathering angles in the wing span direction. The micro flapping robot has two wings and does not have the tail plane. The micro flapping robot flied stably for 12 minutes, which was the battery’s duration. The elastic deformations of a wing are one of the important parameters to realize stable flight performance.