Development of a Small Jumping Mechanism Inspired by the Hip Joint Structure of Issus coleoptratus nymphs

Abstract

We develop a small jumping mechanism that mimics the unique joint of Issus coleoptratus and Alpheus brevicristatus.Issus coleoptratus nymphs have a gear-like mechanism on the hip joint of the hind legs, which enables them to synchronize the leg motion of a jump to maintain the posture. Alpheus brevicristatus has a cocking-slip joint on its claw, which enables to close the claw instantaneously in water. Mimicking and integrating these unique joints, we design a simple jumping mechanism. The experimental results show that the designed mechanism jumps up to 140 cm with maintaining the posture, which is a good and unique performance compared with conventional jump robots. Also, while the leg synchronization is slightly inferior, the takeoff speed is calculated as 5.2 m/s, which is on par with the best record of Issus coleoptratus nymphs.