Using NI1752 smart camera from LabView

[phoenix_777]

Hi,

    My project involves image processing using images from a NI1752 camera.  I have a Rockwell PLC which makes a tag high when image needs to be taken.  I am accessing this tag in LabView using OPC client.  I would now like to use this signal as a trigger for camera to take the image and sent it back to labview.  I dont want to use VBAI as I need to use some OpenCV functions along with it.  Hence I want to implement this completely in LabView.  Please suggest a method to do so.  How can I use IMAQ vi's to get the images from camera?

Best,

Gibin Joe

[DigDoug · Accepted solution]

Hello,

It sounds like what you want is a software trigger based on the high tag from the Rockwell PLC. It sounds like you are not having trouble accessing the tag in LabVIEW. We have a nice example, "HL Triggered Grab (NI 17xx Series).vi", of software triggering for NI 17xx devices using IMAQ functions. This example can be found in LabVIEW by navigating to Help > Find Examples > Browse > Hardware Input and Output > Vision Acquisition > NI-IMAQ > Signal Input and Output > HL Triggered Grab (NI 17xx Series).vi.

You can modify this VI to send the software trigger based on the tag from the PLC rather than the user clicking the Send Software Trigger button.

Have a great day,

[phoenix_777]

Hi,

    Thanks for your reply.  I have one more question.  When we are executing the VI under the camera (by adding new targets and devices), is the VI being run on the camera or on the computer to which camera is connected?

Best,

Gibin

[SoarOnSon]

Hi Gibin,

The VI will be running on the camera. VIs will run on the target that they are placed under in the LabVIEW project.

Josh

Applications Engineer

National Instruments

[phoenix_777]

Hi,

   Thank you for the reply.  If I acquire an image from the camera using the trigger, is it possible to send the image to a vi running on the computer?  I need to run the image through a dll file.  I understand that I cannot run the dll on the camera.  Also, is it possible to use OPC client on the camera VI?  I am accessing the PLC tag on LabView using OPC variable which is used as a trigger for the camera.  I have been trying to modify HL triggered camera.vi to use the OPC tag value, but I cannot figure out a way to do it.

Best,

Gibin

[yea_likethecity]

Hi Gibin,

This may be a good topic for a new thread since this thread has been marked as answered and may not see as much attention as a new thread. Regarding your question, by my understanding you are successfully acquiring an image from your smart camera and wish to transfer the image to another computer so you can use it with a DLL.

Please take a look at this knowledgebase article and see if these options look reasonable:

Streaming IMAQ Images Over a Network (or Internet)

http://digital.ni.com/public.nsf/allkb/2E60AF970E49531586256A8C0051332C

Regarding OPC capabilities on the smart camera, it is running the real-time operating system so should be capable of doing anything a real-time target can do. I've found a super good overview of OPC and Real-Time systems you may want to look over:

OPC and Real-TimeSystems in LabVIEW

http://home.hit.no/~hansha/training/labview/topics/documents/OPC%20and%20Real-Time%20Systems%20in%20...

I hope these links are helpful!

Thanks,

Austin E.

Applications Engineer

National Instruments