Quantized sampled-data static output feedback control of the glucose-insulin system

In this paper, the plasma glucose regulation problem for type 2 diabetic patients is studied. A nonlinear time-delay model of the glucose-insulin regulatory system is exploited to design a quantized sampled-data static output feedback control, using only glucose measurements. It is shown that the proposed control law achieves semiglobal practical stability of the related quantized sampled-data closed-loop glucose-insulin system with arbitrary small steady-state tracking error. The controller involves past values of the glucose, which may not be available in the buffer, for instance because of non-uniform sampling. Such a drawback is overcome by means of spline interpolation. Furthermore, quantization in both input and output channels are taken into account. A pre-clinical validation, concerning the performances of the proposed glucose regulator, is carried out by means of a well-known simulator of diabetic patients, broadly accepted for testing insulin infusion therapies. The simulation results pave the way for further clinical evaluation.