Stable Rotation of a Parametrically Excited Double Pendulum

Abstract

Abstract: The rotation of a double pendulum with a dc motor installed between the �rst and second pendulums was investigated using both experiments and numerical computations. The first pendulum can rotate freely around one end, while the second pendulum is attached to the other end of the first pendulum � the dc motor attached to the first pendulum causes the second pendulum to rotate with respect to the first pendulum. We clarify that there is a range of rotation speed in which the first pendulum rotates at the same, one-half, or one-third of the rotation speed of the second pendulum, and the stable rotation of the double pendulum is realized without torque control of the dc motor and report the characteristics of the stable rotation of the double pendulum