A ferrofluidic actuator for an implantable artificial heart

The feasibility of using a ferrofluidic actuator for an artificial heart was studied. A ferrofluidic actuator directly drives magnetic fluids simply by applying a magnetic field to the ferrofluids and does not require a bearing. Magnetic fluid in a U-shaped glass cylinder was placed in an air gap of a solenoid. When a magnetic flux of 0.32 T was applied to the interface of the ferrofluid and air, the ferrofluid was displaced and a pressure of 7.58 kPa (57 mm Hg) was obtained. An array of three poles of solenoids was mounted near the U-shaped glass cylinder. The solenoids were sequentially activated and deactivated. A pressure of 9.98 kPa (75 mm Hg)/-1.33 kPa (-10 mm Hg) was obtained. Calculations indicate that a magnetic flux of 0.49 T is enough to obtain a pressure of 13.3 kPa (100 mm Hg). A ferrofluidic actuator is promising for use with an implantable artificial heart.