On the concept of a transmission absorber to suppress internal resonance

Internal resonances within vibration isolators have been shown to increase force transmission and consequently radiated noise from supporting structures. Previous research has successfully used dynamic vibration absorbers to attenuate internal resonances. This paper introduces the term transmission absorber to describe a system that exerts both restoring and inertial forces proportional to relative motion. A novel uni-axial vibration isolator concept incorporating transmission absorbers to suppress internal resonance is proposed and theoretically compared with an isolator including dynamic vibration absorbers. The designs are optimised by using a combination of particle swarm and gradient-based optimisation algorithms. It is shown that the proposed isolator concept, incorporating transmission absorbers, has the potential to outperform previous designs, demonstrating force transmissibility levels approaching those of an ideal isolator.