A novel insulin delivery algorithm in rats with type 1 diabetes: the fading memory proportional-derivative method

Artif Organs. 2005 Aug;29(8):599-607. doi: 10.1111/j.1525-1594.2005.29096.x.


An algorithm designed to automatically control insulin delivery was tested in rats with Type 1 diabetes. This nonlinear algorithm included a fading memory component of proportional and derivative errors in order to simulate normal insulin secretion. Error-weighting functions for the proportional and derivative terms were used with a performance index designed for error adaptation. In the first version of the algorithm, the proportional gain was adaptively varied. In the second version, a low rate of basal insulin delivery was adaptively varied. Six 6-h studies with each version were conducted using frequent blood sampling and intravenous insulin delivery. In Version 2 studies, blood glucose levels during the last two hours were well-controlled and significantly lower than in Version 1 (118 +/- 2.0 vs. 130 +/- 2.9 mg/dL). Neither version produced hypoglycemia. Future research using this algorithm needs to focus on automated glucose sensing in combination with insulin delivery.

Publication types

  • Research Support, N.I.H., Extramural
  • Research Support, Non-U.S. Gov't
  • Research Support, U.S. Gov't, P.H.S.

MeSH terms

  • Algorithms*
  • Animals
  • Blood Glucose / analysis
  • Diabetes Mellitus, Experimental
  • Diabetes Mellitus, Type 1 / drug therapy*
  • Infusion Pumps, Implantable
  • Insulin Infusion Systems*
  • Models, Biological
  • Rats


  • Blood Glucose