Pop! Observing and Modeling the Legless Self-righting Jumping Mechanism of Click Beetles

Click beetles (Coleoptera: Elateridae) have evolved a jumping mechanism to right themselves when on their dorsal side, without using their legs or any other appendages. This paper describes and analyzes the stages of the click beetle jump using high-speed video recordings and scanning electron micrographs of four beetle species, namely Alaus oculatus, Ampedus nigricollis, Ampedus linteus and Melanotus spp. The body of the click beetle is considered as two masses linked by a hinge. Dynamic and kinematic models of the jump stages are developed. The models were used to calculate the hinge stiffness and the elastic energy stored in the body during the jump. The modeling results show agreement with the experimental values. The derived models provide a framework that will be used for the design of a click beetle inspired self-righting robot.