High-order sliding-mode control for blood glucose: Practical relative degree approach

High order sliding mode controller (HOSMC) is proposed for blood glucose regulation. With this aim a novel concept of Practical Relative Degree (PRD) and a method of its identification are suggested. First, for PRD identification method is applied for the most simple (Bergman Minimal Model) and the most complicated (Sorensen Model) models concluding that the common PRD for both models is three. Then, a third order quasi-continuous control law was designed. The proposed control law has been tested on simulations for a third model (Hovorka Model), and both above mentioned models. Finally, the experiments are performed with rats just to show that control design based on PRD three is efficient.