Carbon nanotube composite for application in gait analysis

Ulceration as a complication of diabetes mellitus is caused by high recurrent pressures at the foot, which may even lead to amputation. Risk factors of diabetic foot ulcers are diabetes, polyneuropathy and obesity. A gait analysis study including healthy, obese and diabetic persons was accomplished to determine characteristic plantar pressure distribution patterns between these groups. By analyzing the resulting roll-over-patterns, it should be possible to derive better sensor design criteria for new pressure sensing systems tailored on the specific disease pattern. The current available instruments for measurement of plantar pressure distribution are prone to mechanical overload and too expensive for everyday treatment of patients with diabetic foot syndrome. Thus a new low-cost, flexible pressure sensor system is in development. Therefore a pressure sensitive carbon nanotube-polymer composite was prepared and stencil printed on polymer foil. The printing process enables also the economical production of a flexible, piezoresistive film. The resistance change under applied load on the nanotube-polymer film was investigated using compression tests.