Active insulin infusion control of the blood glucose derivative

Abstract

Close control of blood glucose levels significantly reduces vascular complications in Type I diabetes. A control method focusing on the rate of change of blood glucose level is developed to utilize emerging technologies in blood glucose biosensors. The controller developed provides tighter, more optimal control of blood glucose levels, while robustly handling variation in patient response and sampling rate. Particular emphasis is placed on the controller simplicity and robustness necessary for medical devices and implants. A PD controller with a heavily weighted derivative term is found to outperform the more proportional-weighted controllers in oral glucose tolerance testing. Simulation results show reductions of over 50% in the magnitude and duration of blood glucose excursions from basal levels that are slightly better than normal non-diabetic response as modelled. Comparison with normal response indicates that the physiological control system has some measure of both proportional and derivative control as the basis of glucose regulation.