The control algorithm is derived from physiological experiments carried out by other groups which have demonstrated how the beta cells in the pancreas produce insulin in people without diabetes. Utilising the data from these experiments it has been possible to implement the behaviour of the beta cell in software and we have used a simulator with 200 virtual patients to demonstrate the safety and efficacy of the software. The data from the simulator is attached to this application as an appendix. The simulator was developed from human data and takes into account sensor errors, sensor placement, route of insulin administration and meal-time glucose absorption. It has been approved by the FDA in the United States as a step in the pathway of developing an artificial pancreas and has been validated against human data. In the clinical validation device the control algorithm is implemented on a printed circuit board using a programmable micro-controller.