  This study examines the concept of axisymmetric actuator based on the
magnetorheological membrane, electromagnet and permanent magnet. The
construction of the actuator enables its application in wide range of practical
devices like pumping, loudspeaker or varying-stiffness button. This work will
highlight its working principle especially the influence of permanent magnet.
Furthermore, the model of devices will be defined relaying on the Hammerstein
model. To show the properties of the actuator and to perform the model
identification, the set of experiments was run taking into account static and
dynamic working conditions.
