- #1
dominicfhk
- 11
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Homework Statement
Hi, guys. I am watching this guy on youtube explaining block diagram of close and open loop system. While I understand how a close-loop transfer function is equals to C(s)/R(s) = G(s)/{1+G(s)H(s)}, I don't quite understand how the transfer function of an open-loop system equals B(s)/E(s) = G(s)H(s).
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Shot at 2012-07-23
Homework Equations
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The Attempt at a Solution
I thought a transfer function is defined as the laplace transformation of a system output over the laplace transformation of a system input, which is C(s)/R(s). So why not the open loop transfer function equals C(s)/R(s) = G(s)? The feedback loop is disconnected, why we still need to take that into account? Or is he redefining the feedback as the output of the system, instead of C(s)? It so, it is a standard practice even outside his class? Thank you so much!
Edit:
Link to the video: http://www.youtube.com/watch?v=X4hPVxZlrPU&feature=bf_next&list=PL5105727DD6E8DE98
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