LOW-COST MR FLUID SPONGE DEVICES

A variety of robust, high-strength, MR fluids and devices that enable the benefits of controllable fluid technology are now commercially available. Commercial, mass-produced devices include rotary brakes for use in exercise equipment, real-time controllable vibration dampers for truck seats and adjustable linear shock absorbers for racing cars. Recently, a new way of using MR fluids in which the fluid is contained in an absorbent matrix has been developed. Such MR fluid sponge devices enable the benefits of controllable MR fluids to be realized in cost sensitive applications. Most of the high-cost components normally associated with a fluid filled device can be eliminated with this approach. Low-cost, controllable MR fluid sponge dampers are particularly appropriate for moderate-force vibration control problems where a high degree of control authority is desired such as a new generation of high-performance, home washing machines now being developed.