CHAPTER 3. DESIGN PATTERN FOR MACHINE VISION APPLICATIONS
15
Data highway:
The
data highway
is a combination of a LabVIEW
cluster
and a
while-loop shift register. The cluster is a collection of front-panel controls stored
as a “type def” (type definition); any change to the type definition propagates
throughout the entire project. A cluster constant initializes the while-loop shift-
register and defines the data highway “lanes.” Because the data highway passes
through the case structure subdiagrams, each QSM state can read and write
values that in turn can be accessed by every other state.
1.
– Change a data highway lane name: edit the
type def, and then observe the change in the bundle/unbundle functions.
2.
– Create a new data highway lane: edit the type def,
bundle and merge, and access in another state.
3.
– Remove an unused data highway lane: edit the
type def, delete the control, remove the element in the cluster bundle.
4.
– Add a custom lane: create a control from the
Vision Assistant Express VI indicator output, convert to type def, save
type def as a control, add the control to the data highway, merge the Vision
Assistant Express VI output onto the data highway, and then retrieve the
value in another state.
“state” type def:
The
state
enumerated data type control selects the subdiagram
in the case structure.
state
is a type definition, therefore any modifications prop-
agate throughout the project. Changing a state name also changes the name in
the case-structure selector. The
state
and the case-structure are closely related,
therefore these videos show how to edit both at the same time.
1.
– Review the standard states (qsm, myRIO, image), the
example application-specific state, and the expansion states.
2.
– Change a state name: edit the subdiagram label,
open the state type def, edit the enumerated datatype control, observe the
changed name in the case-structure subdiagram.
3.
– Reposition a state in both the state type def and in
the case structure’s subdiagram ordering.
12
(0:54)
13
(1:27)
14
(0:47)
15
(2:58)
16
(2:18)
17
(1:09)
18
(1:25)
Summary of Contents for NI myRIO
Page 1: ...Ed Doering NI myRIO Vision Essentials Guide...
Page 2: ......
Page 11: ...Part I Machine Vision Fundamentals...
Page 12: ......
Page 31: ...Part II Introductory Machine Vision Projects...
Page 32: ......
Page 38: ...32 CHAPTER 4 CAMERA SETUP...
Page 44: ...38 CHAPTER 5 STEREO VISION...
Page 61: ...Part III Machine Vision Application Projects...
Page 62: ......
Page 72: ...66 CHAPTER 8 COIN COUNTER...
Page 86: ...80 CHAPTER 10 KEYED OPTICAL LOCK...
Page 92: ...86 CHAPTER 11 DMM TEST STAND...
Page 134: ...128 CHAPTER 17 MARBLE SORTER...
Page 135: ...Part IV Appendices...
Page 136: ......
Page 143: ...B MXPandMSPConnectorDiagrams Figure B 1 MXP myRIO eXpansion Port connector diagram...
Page 144: ...138 APPENDIX B MXP AND MSP CONNECTOR DIAGRAMS Figure B 2 MSP miniSystem Port connector diagram...
Page 148: ...142 APPENDIX D BUILD A STAND ALONE APPLICATION...
Page 149: ...E MarbleSorterConstructionDetails To be continued...
Page 150: ...144 APPENDIX E MARBLE SORTER CONSTRUCTION DETAILS...
