Application of Fuzzy Logic Controller for Intensive Insulin Therapy in Type 1 Diabetic Mellitus Patients by Subcutaneous Route

The work we describe here is aimed at assisting out-patients affected by insulin dependent diabetes mellitus with an advisory/control algorithm. This advisory/control algorithm incorporates expert knowledge about the treatment of this disease by using Mamdani type fuzzy logic controllers to regulate the blood glucose level (BGL) when the diabetic patient is subjected to a glucose meal disturbance or fluctuations in the measured glucose level due to error in the measuring instrument. We proposed two-level architecture for control system. The goal of the Low Level Module is to suggest the next insulin dosage of both short and intermediate acting insulin (Regular and NPH) formulation that are programmed in a three-shot daily basis before meals, depending on the blood glucose measurement. The combined preparation is then injected by the patient through a subcutaneous route. The High Level Module adjusts the maximum amounts of insulin provided to the patient in a time-scale of days. This module aims to work as a supervisor of the low level module. Simulations are illustrated, using a flow-limited model for diabetes mellitus based on the work of Puckett. Key-Words: Diabetes mellitus, Fuzzy logic controller, Intensive insulin therapy