# Natural frequency second order transfer function

#### Ande

Joined Feb 3, 2017
44
I have been attempting to solve the problem attached (question 1). I am however stuck on getting an expression for the natural frequency. Please help in this regard. My attempt is also attached.

#### Attachments

• 37.1 KB Views: 6
• 66.7 KB Views: 6

#### drc_567

Joined Dec 29, 2008
1,107
... something is not quite right with your fractional multiplication. Try multiplying numerator and denominator by the s(s+1) factor.
... You are given the percent overshoot. You can find a formula for $$\zeta$$, given PO ... ought to be in the text.

#### MrAl

Joined Jun 17, 2014
8,234
I have been attempting to solve the problem attached (question 1). I am however stuck on getting an expression for the natural frequency. Please help in this regard. My attempt is also attached.
Hello,

I agree with the previous post in that your math is not correct when calculating Gs/(1+Gs*Hs).
Try that again and if successful you will see the right constant in the denominator which represents w^2.

Also, the diagram was extremely hard to read. Here is a better diagram.

#### Attachments

• 71.1 KB Views: 4