On the Edge of Chaos of Closed Chain Underactuated Mechanism and Its Complexity

摘要

The edge of chaos is the transitory region between deterministic and chaotic motion, which might be used to control chaos. In this paper, experiment and simulation are carried out to find the edge of chaos for a planar closed chain five-bar underactuated mechanism. The complexity of chaos is revealed. Approximate entropy is employed to describe the random distribution of input angular velocities corresponding to the periodic motion and chaotic motion in the edge of chaos. The difference between the passive joints in a closed chain and in an open chain underactuated mechanism is analyzed. Also the effects of inertia forces and moments on the motion state of nuderactuated mechanism are analyzed based on the results of experiment and simulation.