H₂ Optimization of Damped-Vibration Absorbers for Suppressing Vibrations in Beams With Constrained Minimization

Vibration absorbers are efficient and robust tools for reducing vibration and noise. Researchers use various alternative approaches and validate their methods with examples consisting of mass-spring-damper systems. Focusing on the minimization of the vibration amplitudes via passive absorber approach, a new and efficient method for calculating the optimum parameters of N absorbers attached to a uniform beam with M mode shapes (where N and M are any positive integers) has been developed. First, for the most general case, dissipation due to damping, kinetic, and potential energy and the effects of external forces are analyzed. The Lagrange's equation is used to provide the state space representation of the system. State space representation of a system with N absorbers and M mode shapes is composed. On the basis of the state space representation and the Lyapunov function, the H₂ norm of the transfer function of the system is utilized in the newly developed optimization package. The system output is minimized by the optimization algorithm and displayed with a comparison between cases without an absorber and with randomly selected absorber parameters. As a conclusion, with the help of this method for calculation of optimal absorber parameters, one can easily design a mechanical system according to design criteria.