Penn State has, for over 25 years, been a world leader in development of artificial hearts and ventricular assist devices. I have been involved in this effort for over 20 years. My principal work has been in development of control systems that permit these devices to vary their output according to the body's needs. Presently, we are completing the development of a total artificial heart and ventricular assist device that require no interruption of the patient's skin to operate. Projects aimed at development of new devices include studies of scaling of blood pumps to smaller sizes, and development of a next-generation ventricular assist device. These programs are funded by the National Institutes of Health.

We are also investigating the use of electroactive polymers - flexible materials that change shape or elastic properties in the presence of an electric field - for use in medical devices. In "conventionally engineered" blood pump systems, a passive pump is actuated by a separate electric motor drive. In the natural heart, the blood container and the active elements are intertwined. Electroactive polymers may permit tighter integration of the pump and actuator in blood pumps and may find additional applications in both prosthetics and interventional devices.

Another line of research involves development of advanced surgical tools, particularly for minimally invasive surgery. Presently, surgeons performing minimally invasive procedures have limited dexterity and a highly compromised sense of touch. In microsurgery, operations on structures a few millimeters or less in scale, surgeons work at the limits of human movement ability and have limited feel due to the mismatch between human-scale forces and the forces involved in the manipulation of tiny structures. Along with faculty in the department of Mechanical Engineering, I am working to develop advanced end-effectors that would provide improved dexterity and useful force feedback. These programs are presently funded internally and through gift funds.

Other research interests include applications of nanotechnology, targeted therapies and diagnostics, and new approaches to tissue engineering.