second pole face of the first electromagnet a second mounting plate is coupled to the second face of the second layer of soft matrix magnetorheological material the second mounting plate adapted to be coupled to a load mass application_number US 87309910 A description persons of ordinary skill in the art will realize that the following description of the present invention is illustrative only and not in any way limiting other embodiments of the invention will readily suggest themselves to such skilled persons any of the controllable smmr material shock and vibration isolation devices disclosed herein can be rigidly connected between a frame chassis and a vibrating mass where the frame chassis is subjected to a vibration input the device is also connected to a power supply which is connected to a control system the device needs to be equipped with vibration sensors that feedback the sensor signals of the frame chassis and vibrating mass respectively to the control system based on the sensor signals the power supply provides electric current to the smmr device upon application of the electric current a magnetic field is generated across the smmr device to control the stiffness of the smmr device referring first to fig1 one embodiment of an smmr device 10 is composed of a lower mounting plate 12 an upper mounting plate 14 multiple controllable smmr 16 at least one electromagnet core 18 around which electromagnet coils 20 are wound the embodiment of fig1 is shown including two electromagnet assemblies the electromagnet coil 20 of the leftmost one of which is shown cut away to show the core 18 around which electromagnet coil 20 is wound.