A major cause of illness and disability in diabetic patients is complications affecting the lower limbs, particularly the feet where loss of feeling may result in ulcerations, and ultimately to partial or total amputation. Traditional remedies for this problem still remains in measuring the foot pressures and then designing a passive shoe insert that absorbs the high pressures. This process may then be repeated multiple times during the lifetime of the patient. This paper describes the conceptual design of an automatic system that monitors and controls the pressure levels in diabetic patients’ feet in real time. The scheme is based on the constant measurement of pressure levels and then actively changing the shape of the shoe insert so as to decrease the high pressure levels. The sensing and the actuation is done by the use of smart materials powered by a battery pack in the insert. The sensing is done by using piezoceramic patches while the actuation is done by use of electroactive polymer (EAP) actuators. All the circuitry is envisioned to be on a single VLSI chip embedded in the shoe insert, hence making the shoe insert completely autonomous. The greatest strength of the system is that it is an active real time system that will adapt to changes in the locations of high stress points, and, hence, is far superior to currently used passive shoe inserts and other forms of diabetic foot care.
Proceedings of the Society of Experimental Mechanics
Hahn, Carrie; Mahajan, Ajay; and Schoen, Marco P., "Diabetic Patients Foot Care Using Smart Materials to Prevent Ulcerations/Amputations" (2002). Mechanical Engineering Faculty Research. 515.