Dynamic modeling and mode analysis of flexible-link, flexible-joint robots

This paper presents a systematic approach to dynamic modeling and mode analysis of a single-link flexible robot, which has a flexible joint and a hub at the base end and a payload at the free end. Accurate modes of the system are obtained analytically. The following important conclusions are drawn: (1) even a small joint flexibility can significantly affect the system frequencies; (2) the fundamental frequency is insensitive to the hub inertia or payload inertia; (3) for a given flexible system, the fundamental frequency is mainly affected by the payload mass, while the second frequency is mainly affected by the payload inertia.