Observer-based linear state-dependent control for blood glucose regulation in type 1 diabetic patients with unknown delays

Abstract

This paper presents a control strategy for blood glucose regulation in the presence of a time-varying delayed input, where the delay is unknown. The proposed control scheme is based on an observer-based linear state-dependent (LSD) (a subclass of the general linear parameter varying (LPV) framework) control with $H_{\infty }$ criterion. This proposed control regulates glucose levels in response to meal intake. A novel LSD system representation is used to relax the inherent conservativeness of the nonlinear system. First, the observer achieves an estimate of the current state vector despite the delayed input, where the time-varying unknown delay can be relatively long. Thus, the control law will perform well in the presence of a long unknown delay. The observer-based control scheme is validated by considering different meal disturbances and unknown delay scenarios.