A switching control strategy for the attenuation of blood glucose disturbances

Abstract

In this computational study we consider a generalized minimal model structure for the intravenously infused insulin-blood glucose dynamics, which can represent a wide variety of diabetic patients, and augment this model structure with a glucose rate disturbance signal that captures the aggregate effects of various internal and external factors on blood glucose. Then we develop a model-based, switching controller, which attempts to balance between optimal performance, reduced computational complexity and avoidance of dangerous hypoglycaemic events. We evaluate the proposed algorithm relative to the widely studied proportional-derivative controller for the regulation of blood glucose with continuous insulin infusions. The results show that the proposed switching control strategy can regulate blood glucose much better than the proportional-derivative controller for all the different types of diabetic patients examined. This new algorithm is also shown to be remarkably robust in the event of concurrent, unknown variations in critical parameters of the adopted model. © 2009 John Wiley & Sons, Ltd.