Triggering two cameras simultaneously

[Dayne]

Hi,

I am currently working on an application which requires that two cameras be triggered simultaneously to acquire images of labels.  The application is a vision system for a dual label machine.  A PLC output trigger signal tells our vision system when exactly the two labels are stationary.  How does one solve this problem in LabView?  I have been using LabView 7.1 for about two months, but I have not used much of the IEEE 1394 IMAQ functions in LabView yet.

So, any help would be greatly be appreciated.

[Dayne]

I just wanted to clarify that I am trying to trigger two cameras simultaneously to acquire images in LabView 7.1.  Does anyone know how this can be accomplished?

[Irene B]

Hi Dayne,

If the two cameras are being triggered by the same digital line, you can just open the shipping example Triggered Grab.vi (located in the NI Example Finder, which can be found in LabVIEW by going to Help >> Find Examples >> Hardware Input and Output (folder) >> IMAQ1394 >> Signal Input and Output).  Make a duplicate of every IMAQ1394 VI and its connected inputs and outputs (except for the stop button), one series of VIs for each camera.  Here are few suggestions as well:

• For IMAQ1394 Configure Trigger.vi, they can share the same Timeout, Trigger Mode, and Parameter (optional) inputs if they’re going to be triggered with the same external trigger.
• For IMAQ1394 Grab.vi, they can both be in the same while loop.

Hope this helps!
Irene Chow
National Instruments
Applications Engineer

[Ahmad_S]

Thanks for the help Irene. I'll try that out.

[Ahmad_S]

BTW, to avoid any confusion, that's my co-worker's name username (Dayne), which he let me post with when I didn't have an account here.