Lecture 10 ME 176 Reduction Of Multiple Su

22
ME 176 Control Systems Engineering Department of Mechanical Engineering Reduction of Multiple Subsystems

Transcript of Lecture 10 ME 176 Reduction Of Multiple Su

Page 1: Lecture 10 ME 176 Reduction Of Multiple Su

ME 176Control Systems Engineering

Department of

Mechanical Engineering

Reduction of Multiple Subsystems

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Signal Flow Graphs: Elements:

Branches = SystemsNodes = SignalsArrow = Direction of signal flow

Transfer function written adjacent to line.

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Branches

Nodes

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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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Page 10: Lecture 10 ME 176 Reduction Of Multiple Su

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 :

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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.

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