User`s guide

The Root Locus Design GUI
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The Root Locus Design GUI
You ca n also design a compensator using the Root Locus Design Graphical
User Interface (GUI). See Chapter 8 , “The Root Locus Design GUI” for more
information. The Root Locus Design GUI is an interactive graphical user
interface that assists you in designing a compensator by prov iding the
following features:
• Tuning the value of the feedback or compensator gain
• Adding/removing compensator poles and zeros directly on the root locus plot
• Dragging compensator poles and zeros around in the root locus plane
• Examining changesinthe closed-loopresponsewheneverthe compensatoris
changed
• Drawing boundaries on the roo t locus plane for parameters such as
minimum damping ratio, etc.
• Zooming in to regions of the root locus
To initialize the Root Locus Design GUI, simply type
rltool
rltool
can also be called with additional input arguments that allow you to
initialize the plant and compensator used in the Root Locus Design GUI. For
example,
rltool(sys)
initializes a Root Locus Design GUI with the linear time invariant (LTI) object
sys as the plant. Adding a second input argument, as in
rltool(sys,comp)
also initializes the LTI object comp as the root locus compensator.
Whenoneortwoinput argumentsareprovided,therootl ocusof theclosed-loop
poles and their locations for the current compensator gain are drawn. The
closed-loop modelis generated by placing thecompensatoranddesign modelin
the forward path of a negative unity feedback system.