Diabetic Mellitus is a disease caused either due to insufficient insulin produced by the pancreas or the body cells are unable to use the existing insulin. One of the main complications associated with diabetics is neuropathy, which is caused due to complete or partial loss of sensation in the feet and legs that lead to problems like inadequate delivery of nutrients and oxygen to the foot, which will cause healing impairment. In diabetic neuropathic subject, the hardness of foot sole soft tissue gives rise to plantar ulcer development. In this work, a biomechanical model is used to study the plantar distribution of forces in the foot. The dynamic foot pressure distribution during walking is used to carry out a stress analysis. This includes the motion of heel strike, mid-stance, and push off section of the feet during walking. A control strategy is proposed to mitigate the high stress concentration occurring during the walking phase. The control strategy includes a synergy of an adaptive neuro-fuzzy inference controller and for comparison an optimal controller. The actuation is simulated through an external shoe insert. The three-dimensional multi-segment biomechanical model is used in conjunction with experimental data gathered from various literatures for simulation purposes of the proposed control strategy. The proposed intelligent controller focuses on stresses generated by the foot pressure distribution during walking and compares these with stress levels of healthy subjects. The insert changes its shape accordingly to redistribute the pressure levels at various regions so to achieve a pressure distribution equivalent to a healthy subject. It is assumed that the insert can actuate and measure the pressure distribution simultaneously. This could be achieved using smart materials for the shoe insert. The simulation results show the effectiveness of the proposed algorithms and approach.

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