A Snap Mechanism Imitating the Thoracic Joint of a Click Beetle

In this study, we focused on the thoracic joint of a click beetle and proposed a two-link type snap mechanism. This mechanism mimics the click beetle's principle for storing and releasing elastic energy, and is composed of links, springs, motors, viscoelastic peg, etc. This mechanism normally functions as a general active joint, and can generate snap rotational motion at any time. The developed snap mechanism was likened to a click beetle and the relationships between the mechanism's parameter and jumping characteristics were validated. As a result, we confirmed that the size of the mechanism, weight distribution, and hardness of the ground affect the jumping performance.