title: Reducing Glucose Variability Due to Meals and Postprandial Exercise in T1DM Using Switched LPV Control: In Silico Studies.
abstract: Time-varying dynamics is one of the main issues for achieving safe blood glucose control in type 1 diabetes mellitus (T1DM) patients. In addition, the typical disturbances considered for controller design are meals, which increase the glucose level, and physical activity (PA), which increases the subject's sensitivity to insulin. In previous works the authors have applied a linear parameter-varying (LPV) control technique to manage unannounced meals.
  
  
  
  A switched LPV controller that switches between 3 LPV controllers, each with a different level of aggressiveness, is designed to further cope with both unannounced meals and postprandial PA. Thus, the proposed control strategy has a "standard" mode, an "aggressive" mode, and a "conservative" mode. The "standard" mode is designed to be applied most of the time, while the "aggressive" mode is designed to deal only with hyperglycemia situations. On the other hand, the "conservative" mode is focused on postprandial PA control.
  
  
  
  An ad hoc simulator has been developed to test the proposed controller. This simulator is based on the distribution version of the UVA/Padova model and includes the effect of PA based on Schiavon.(1) The test results obtained when using this simulator indicate that the proposed control law substantially reduces the risk of hypoglycemia with the conservative strategy, while the risk of hyperglycemia is scarcely affected.
  
  
  
  It is demonstrated that the announcement, or anticipation, of exercise is indispensable for letting a mono-hormonal artificial pancreas deal with the consequences of postprandial PA. In view of this the proposed controller allows switching into a conservative mode when notified of PA by the user.
authors.affiliation: National Scientific and Technical Research Council, Buenos Aires, Argentina Departamento de Ciencia y Tecnología, Universidad Nacional de Quilmes, Buenos Aires, Argentina patricio.colmegna@unq.edu.ar.
authors.forename: Patricio H
authors.initials: PH
authors.lastname: Colmegna
authors.affiliation: National Scientific and Technical Research Council, Buenos Aires, Argentina Centro de Sistemas y Control, Instituto Tecnológico de Buenos Aires, Buenos Aires, Argentina.
authors.forename: Ricardo S
authors.initials: RS
authors.lastname: Sánchez-Peña
authors.affiliation: Department of Chemical Engineering, University of California, Santa Barbara, Santa Barbara, CA, USA.
authors.forename: Ravi
authors.initials: R
authors.lastname: Gondhalekar
authors.affiliation: John A. Paulson School of Engineering & Applied Sciences, Harvard University, Cambridge, MA, USA.
authors.forename: Eyal
authors.initials: E
authors.lastname: Dassau
authors.affiliation: John A. Paulson School of Engineering & Applied Sciences, Harvard University, Cambridge, MA, USA.
authors.forename: Francis J
authors.initials: FJ
authors.lastname: Doyle
mesh_terms: D001786:Blood Glucose / Q000032:analysis; D003198:Computer Simulation; D003922:Diabetes Mellitus, Type 1 / Q000097:blood*; D015444:Exercise / Q000502:physiology*; D006801:Humans; D007003:Hypoglycemia / Q000097:blood / Q000517:prevention & control*; D008962:Models, Theoretical; D019397:Pancreas, Artificial
chemical_list: D001786:Blood Glucose
keywords: linear parameter-varying control; postprandial physical activity; switched systems; type 1 diabetes mellitus