National Instruments NI myRIO, Essentials Manual

Page: 109 / 163

CHAPTER 14. COMPONENT PLACEMENT INSPECTOR 103
Figure 14.2: Analyzed output from the vision script with a board that is tilted
and missing a red brick and a yellow brick.
14.1 Technical Approach
NI Vision Assistant Script
The NI Vision Assistant Color Matching step compares a region of interest (ROI)
to a color and indicates whether or not the ROI matches the expected color. This
step can accommodate a compound ROI, therefore multiple sites can be checked
within a single script step. When packaged in a Vision Assistant Express VI
the Color Matching step can generate both a Match Flag (Boolean pass/fail
indicator) and a Match Score (numerical value between 0 and 1000). Study
the tutorial video Check for Matching Color
1
to learn how to set up the Color
Matching step to check multiple component sites for an expected color.
NOTE : The ROIs defined in the Color Matching step depend on a
specific camera resolution, therefore, settle on a resolution early in your
development process to avoid having to redefine the color matching ROIs.
1
http://youtu.be/VmO5fBoZMyE
(3:23)