National Instruments Xmath Interactive Control Design Module ICDM - Manual (Page 50)

Chapter 5 Root Locus Synthesis
Xmath Interactive Control Design Module 5-4 ni.com
Plotting Styles
Selecting View»Locus Select or pressing in the Root Locus
window produces a dialog box in which the user can choose one of many
possible plotting styles. In all cases, the (open-loop) controller and plant
poles and zeros are shown on the plot. On color displays:
• Controller poles and zeros are black
• Plant poles and zeros are red
This serves as a mnemonic: you can manipulate black but not red poles or
zeros. On monochrome displays, the plant poles and zeros are lighter than
the controller poles and zeros. You can always use data-viewing to obtain
more information about a pole or zero. Refer to the
Data-Viewing Plots
section of Chapter 2, Introduction to SISO Design . Figure 5-2 shows a
dialog box for choosing plotting style with standard (default) contours
selected.
Figure 5-2. Root Locus Select Dialog for Choosing Plotting Style