MIE.18 – Orthotic Intelligent Insole for Diabetic Patients

• Vijdan Hanafi
• Tejas James
• Luis Treto
• Abdulkabir Yahya

Due to the continued affliction of diabetes within the country, the team undertook a project to lessen the outcomes of the adverse effects. In this project, the team managed the task of reducing the likelihood of foot ulcers in a person with diabetes. Approximately 18% to 34% of individuals with diabetes will develop a Diabetic Foot Ulcer (DFU). DFUs are the wearing of skin and tissue in the underside of the foot due to repeated pressure experienced by the foot. Lower limb amputations are a severe side effect of DFUs alongside a declining life expectancy. To reduce the pressure, the team researched rheological fluids to reduce the pressure experienced by the foot during gait. When encountering an external stimulus, these rheological fluids can change physical properties, precisely viscosity. After testing two fluids, electrorheological fluid (ERF) and magnetorheological fluid (MRF), ERF affected by electric fields and MRF affected by magnetic fields, a decision was made to move forward with the magnetorheological fluid (MRF). The team measured pressure at regions of the foot that experience the highest stress concentration and placed Low-Density Polyethylene (LDPE) bladders filled with the MR fluid contained within an insole within these regions. The insole also has electromagnets connected to a microcontroller placed under the bladders to alter the MRF’s viscous state. Through the use of MRF, which changes viscosity in the presence of a magnetic field, the bladders would experience a high magnetic field and, in turn, cause a change in the viscosity of the fluid. Upon changing the viscosity of the bladder to a more viscous state, one observed pressure decreases in the higher stress concentration areas. The current medical devices used to heal DFUs are typically more substantial in size and impact upon the function of lower extremities rather than preventing DFUs. These medical devices cannot correctly offload pressure, heightening the risk of future DFUs if not adequately healed. The insole, however, will offload the pressure using MRF by varying the offload based on the individual’s movements, creating a more personalized treatment, thus healing the DFU and reducing the risk of future DFUs.