Vibration Control of Autoparametric System Using MR Dampers in the Pendula Joints

In this paper a three-degree of freedom autoparametric system with a double pendulum including the magnetorheological (MR) dampers in the pendula joints is investigated numerically. The system consists of the two coupled pendula hangs down from the oscillator. Near the resonance regions except multiperiodic and quasiperiodic vibration, also chaotic motion may appear. For characterising a chaotic response the bifurcation diagrams, Poincaré maps and maximal exponent of Lyapunov for different magnetorheological damping parameters are constructed. The influence of damping moment in the pendula joins (described by Bingham’s model) on the phenomenon of energy transfer can be modified by magnetic field. Results show that MR dampers can be used to change the dynamic behavior of the autoparametric system giving semiactive control possibilities.