Design of software controlled insulin infusion by continuous glucose analisis using embeded systems

Automated technique for insulin infusion is reported. The highlighted area of the paper is the design of an insulin infusion pump where the rate of insulin infusion depends on the amount of glucose in the blood. Glucose levels are monitored and calculated quantitatively by introducing amperometric enzyme electrode (glucose sensor) in blood. The amount of glucose is estimated and output of this sensor is electrical signal (mV). Analog signal obtained is converted into digital signal using ADC ICs. The basic principle of this technique is that amount of voltage obtained for normal glucose level is obtained and this voltage is taken as the cutoff frequency for a high pass filter. A stepper motor is connected to infusion pump. The rate and amount of insulin infusing into the blood depends on the speed of the stepper motor. A microcontroller is programmed in such a way that the motor starts working when there is a signal for the filter and the speed of the motor can be varied according to input. Whole setup works on batteries. Level converter is used to match all frequencies and voltages of the components used.