Robust multi-objective blood glucose control in Type-1 diabetic patient

Area of Science:

• Biomedical Engineering
• Control Systems Engineering
• Endocrinology

Background:

• Type-1 Diabetes Mellitus (T1DM) requires continuous blood glucose (BG) monitoring and management.
• Existing BG control systems face challenges with unannounced disturbances and optimal insulin delivery.

Purpose of the Study:

• To develop an automatic, robust, multi-objective controller for subcutaneous BG regulation in T1DM patients.
• To minimize insulin infusion rates while maintaining BG control amidst meal disturbances and external noise.

Main Methods:

• A multi-objective output-feedback controller incorporating H∞, H2, and pole-placement constraints was designed.
• Linear Matrix Inequality (LMI) techniques were employed for controller design.
• The controller was validated using the UVa/Padova T1DM metabolic simulator on adult and adolescent subjects.

Main Results:

• The closed-loop system demonstrated excellent tracking of reference BG levels.
• No hypoglycaemia effects were observed, even during prolonged fasting periods.
• In the presence of a 50gm meal disturbance, adults maintained normoglycaemia for 92% of the simulation time with 0% hypoglycaemia.
• The controller exhibited robust performance against irregular meals, insulin pump noise, and errors.

Conclusions:

• The proposed controller effectively regulates BG in T1DM patients, offering robust performance.
• It achieves normoglycaemia with a reduced insulin infusion rate compared to previously reported controllers.
• The system shows potential for safe and efficient T1DM management in diverse real-world conditions.