Analysis of Free Giant Swing Motions of a 2-DOF Link Mechanism

摘要

This paper investigates the structure of three types of free giant swing motions for a 2-dof link mechanism that were derived by both an optimum trajectory planning method and a forwrard dynamics analysis. Based on the modal analysis to the linearized dynamic equation of motion, we showed that three giant swing motions under zero gravity force are the rigid mode rotation, positive and negative superposition of the vibration mode on it. Since the frequency of the vibration mode decreases with increase in the amplitude of the vibration mode, free giant swing motions are realized at the amplitude at which two modes synchronize. There can exist odd number of periodic motions more than three depending on link parameters. The motion shapes are deformed by gravitational force, and two types of giant swing motions collapse as the motion period increases.