Engineering Control Assignment -

Course work : Closed loop control in the treatment of Type 1 Diabetes

Assignment:

a) What is the transfer function of the human body (process) with insulin input I(s) and actual blood sugar level Y(s) as the output.

b) Without the feedback loop, controller and the pump, the human body is in open loop configuration. Calculate the open loop poles and zeros. Is the human body stable in open loop?

c) Using the control system block diagram in figure 3 and using the transfer functions of each component, show that the closed loop transfer function of the system is given as:

Y(s)/R(s) = K/(s²+s+K)

d) Calculate the suitable value of K for the controller, so that the percentage overshoot due to the drug (insulin) injection is approximately 5%.

Hint: ζ = -ln(%0S/100)/(√(π²+ln²(%0S/100))

e) Using the K value calculated in d), substitute in c) to calculate the closed loop poles and zeros and sketch them on the Pole-zero map. Is the closed loop system stable and what type of response is expected?

f) Calculate the time, when we expect the maximum output actual blood sugar level to occur?

g) How long does it take the body to reach 98% of the desired blood sugar level?

h) Using the notes from Simulink lab, create and simulate the control system as shown in figure 3. Use a unit step input, with the K value calculated in part d), pump transfer function and human body transfer function derived in a). (See help notes on next page for creating the Simulink model).

i) Once you have simulated the step response compare your results with theoretical values calculated in d, f & g?

Attachment:- Assignment File.rar