Laplace and differential equation problem.HELP

AI Thread Summary
The discussion revolves around finding the differential equation that relates the input and output of a parallel system after determining its transfer function. The transfer function is given as H(s) = (s + 1) / (s(s + 1) + 1). The user seeks guidance on how to derive the differential equation from the transfer function and is advised to multiply the output by the denominator and the input by the numerator. After following the advice, the user successfully derives a differential equation but is uncertain of its correctness until graded by their teacher. The conversation highlights the process of transitioning from a transfer function to a differential equation in control systems.
rforrevenge
Messages
10
Reaction score
0

Homework Statement



I have this parallel system and i have found its transfer function.Now i have to find what is the differential equation that links the input and the output

Homework Equations



u(t)=input, w(t)=output H(s)=w(s)/u(s)=s+1/s(s+1)+1 -->transfer function

The Attempt at a Solution



I think i have to go backwards starting from H(s) but i don't know how to do it

Any help?
 
Physics news on Phys.org
Multiply w by the denominator and u by the numerator of the TF.
Remember that the inverse transform of sF(s) is \frac{df}{dt} - f(0^-) and that of s^2F(s) is \frac{d^2f}{dt^2} - \frac{df}{dt}(0^-) - f(0^-).
 
Thank you.I did it and i found a DE. Don't know yet if it is correct,though.I will tell you as soon as my teacher grades my paper.Thank for the help,though. I really appreciate it.
 
Back
Top