Passive brachiation. Towards motion in trees with robotic snakes

Euler-Lagrange dynamic behavior of a passive underactuated brachiation motion of a 6DOF coplanar Modular Snake Robot was analyzed using simulation. The experiments were executed with a robot featuring a catenary curve hanging by two horizontally separated support points. The initial conditions of the simulations were set by varying the separation of the support points before motion occurred. After releasing one robot end, we recorded the resulting evolution of joint positions, velocities and accelerations, as well as the center of mass position. The resulting performance related to distance reached, height achieved and the equalized conversion of energy was analyzed to identify the ranges for the initial conditions that make this motion feasible within a real robot.