One of the important methods by which vibrations of a body are reduced is by the use of vibration absorbers or tuned absorbers. This technique involves attaching a spring mass system, called absorber system, to the vibrating body (also called primary body).
This paper is a case study dealing with a primary system, here a driver seat, to attenuate its response to disturbance. It has high damped natural frequency compared to the base excitation frequency, which was collected from test data. The paper discusses the variations in absorber and primary system damping ratio, mass ratio variation and usage of variable stiffness. Detailed analysis showed instability in the tuned system due to the large gap between the primary body's damped natural frequency, and the target base excitation frequency.
In order to address varying target excitation frequency, an adaptive tuned absorber is suggested. It consists of air column responsible for the variable absorber system stiffness that accommodates the variation in the primary system and change in base excitation frequency.