Manipulating The Design Parameters; Manipulating The Weight Transfer Function; Infeasible Parameter Values - National Instruments Xmath Interactive Control Design Module ICDM User Manual

Chapter 8 H-Infinity Synthesis

Manipulating the Design Parameters

Manipulating the Weight Transfer Function

Infeasible Parameter Values

Xmath Interactive Control Design Module
The parameters , , and can be changed using the associated slider or
variable edit box. If the user types in a value that is outside the current slider
range, the slider range will automatically adjust. The user can change the
ranges for the sliders using the Ranges window. Refer to the Infeasible
Parameter Values section for what happens when the requested value of
is infeasible.
The parameter also can be changed graphically, by grabbing and
dragging the dashed horizontal line in the singular value plot.
When Weight Zero Editing is enabled, the user can graphically
manipulate the zeros of the weight transfer function W on the plot labeled
Weight Poles & Zeros. Refer to the
Zeros section of Chapter 2,
discussion of how to move, add, delete, or edit these zeros graphically.
If the user requests an infeasible value for , then it will be reset to an
approximation of the optimal (that is, smallest possible feasible) value,
In this case, four (logarithmic) bisection iterations are used to determine ,
a feasible value of such that:
log
new
where is the value that is reset to
new
is the optimal (smallest possible feasible) value of
opt
is the previous value of
prev
is the value of requested by the user
req
After the H Synthesis window has determined a lower bound on
displayed in the singular value plot. It will disappear if the user changes the
control cost, sensor noise, or output weight parameters.
Graphically Manipulating Poles and
Introduction to SISO
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Design, for a general
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