I don't know how to introduce the block (s+6) in simulink

I have the following block diagram I want to enter into Simulink, but I am having trouble as I do not know a way to enter the (s+6) block. I do not seem to find a way to do it with a transfer function as it is required that the numerator and denominator have the same degree.

Answer 1

[Paul]

Hi Carlos,

One option would be to use block diagram manipulation. For example (there is at least one other approach):

a) change the s+6 in the feedback path to 1

b) change 1/(s^2+9) to (s+6)/(s^2+9)

c) change 12 to 12/(s+6)

d) add 1/(s+6) on the line for Y(s) to right of the node that branches off for the feedback signal; Y(s) is now the output of this added transfer function

That should give you the same closed-loop transfer function Y(s)/R(s). Are there other transfer functions of interest?

[Carlos Puente]

Hi Paul! Thanks for your help! That is the only transfer function of interest in this particular problem.