Improvising tuning techniques of digital PID controller for blood glucose level of diabetic patient

Abstract

In this paper the digital PID (Proportional-integral derivative) controller is designed based on controlling the blood glucose level of diabetic patient. The main objective is to design a digital PID controller for blood glucose level of diabetic patient which can inject external insulin to the patient in a accurate controlled way. The blood sugar level of the patient is considered as input variable & injected insulin level is considered as output variable which is to be manipulated. A dynamic model is constructed & transfer function is defined for this system. Using various tuning rules like Cohen-Coon method, Astrom-Hagglund or AMIGO method and Chien-Hrones-Reswick (CHR) method the Proportional, Integral & Derivative coefficient. The tuning responses are studied & parameters are compared. Best response given by the PID is converted into Digital PID. In this paper we also studied different transformation method to convert the conventional PID into the digital PID controller.