Engineering the artificial pancreas

The development of control systems for medical applications poses particular challenges, distinct from the applications in electrical engineering, mechanical engineering, and chemical engineering. Physiological systems involve a myriad of networked subsystems, with multiple feedforward and feedback loops, and interactions at many levels. There is both interpatient dynamic variability as well as intrapatient variability. Real-time measurement of key physiological variables is often not possible. Quantifying clinical objectives is another challenge, as medical metrics do not easily translate into the mathematical performance measures common in control systems theory. In this talk, I will focus on the challenges of biomedical control for Type 1 Diabetes Mellitus (T1DM), a chronic autoimmune disease affecting approximately 35 million individuals world-wide, with associated annual healthcare costs in the US estimated to be approximately $15 billion. Current treatment requires either multiple daily insulin injections or continuous subcutaneous (SC) insulin infusion (CSII) delivered via an insulin infusion pump. Both treatment modes necessitate frequent blood glucose measurements to determine the daily insulin requirements for maintaining near-normal blood glucose levels.