ME 176Control Systems Engineering
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Mechanical Engineering
Reduction of Multiple Subsystems
Signal Flow Graphs: Elements:
Branches = SystemsNodes = SignalsArrow = Direction of signal flow
Transfer function written adjacent to line.
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Branches
Nodes
Signal Flow Graphs: Each signal is sum of signals
flowing into that node.
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Signal Flow Graphs: Cascade Form Represent Singals as Nodes Interconnect the nodes with system branches
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Signal Flow Graphs: Parallel Form
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Signal Flow Graphs: Feeddback Form
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Signal Flow Graphs:
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Signal Flow Graphs:
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Signal Flow Graphs:
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Mason's Rule: Definition
Loop Gain:
The product of branch gains found bytraversing a path that starts at a node andends at the same node, following the directionof the signal flow, without passing through thenode more than once.
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Mason's Rule: Definition
Forward Path Gain:
The product of gains found by traversinga path from the input node to the outputnode of the signal-flow graph in thedirection of signal flow..
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Mason's Rule: Definition
Nontouching Loops:
Loops that do not have any nodes in common
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Mason's Rule: Definition
Nontouching-loop Gain:
The product of loop gains from nontouchingloops taken two, three, four, or more at atime.
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Mason's Rule:
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Mason's Rule: Example Step 1 : Identify the forwardpath gains:
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Mason's Rule: Example Step 2 : Identify the loop gains:
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Mason's Rule: Example Step 3 : Identify the loop gains (2 @ a time):
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Mason's Rule: Example Step 4 : Identify the loop gains (3 @ a time):
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Mason's Rule: Example Step 5 : Using Mason's rule - evaluate for :
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Mason's Rule: Example Step 5 : Using Mason's rule - evaluate for :
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Mason's Rule: Example Step 5 : Using Mason's rule - evaluate for :
Department of
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Laboratory : Material for the laboratory sessions that come after this lecture can be viewed from the class site at: http://sites.google.com/a/vinta.com/me-176/
Please make sure to read the directions at the bottom of the page for instructions on how to submit the laboratory working sessions.
Department of
Mechanical Engineering
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