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In this blog, I'd like to present a machine vision solution inspired by a real Microscan customer application using the latest connectivity feature in our machine vision portfolio: Microscan Link.

Microscan Link, available in Microscan's AutoVISION „¢ and Visionscape ® machine vision software, is a simplified connectivity tool that allows us to communicate machine vision inspection parameter values between vision tools, between tools and outside systems (like a PLC or PC), or between inspection jobs within the machine vision software platform. In other words, Link enables the remote "set and get" of machine vision input and output across the automation system by way of common communication protocols - for example, Ethernet TCP/IP, EtherNet/IP, or Serial. With all components of a vision system connected via Microscan Link, we can effectively create an inspection network that can be commanded remotely and can run autonomously using pre-programmed inspection parameters.

Let's look at how this technology was applied to a real application in the field. Broadly, our customer's application required us to acquire and send data and triggers between smart cameras without the intervention of an external PC or workstation. By exchanging data directly via integrated machine vision software, our linked smart cameras were able to function independently as one unit. The result is a sort of daisy-chain topology using the Microscan Link framework and two Vision HAWK smart cameras connected via Ethernet.


In the schematic shown above, two Vision HAWK C-mount smart cameras are performing simultaneous inspection tasks on a single PCB - one camera decodes a symbol on one side of the board and the other camera counts components on the other side. The cameras communicate the results of their individual inspection tasks to one another over Ethernet to ensure one complete inspection of the PCB, both front and back. Based on the result of the decoded symbol, the Vision HAWK that performs the decode sends a serial trigger signal to the second camera to begin a count of PCB components. Additionally, the text string decoded by the first camera is sent to the second camera to log the PCB's unique identifier. The second camera then uses the data that it receives from the first camera to output a complete string of ID and inspection data to an operator or external system.

From a programming standpoint, setting up this inspection job in Microscan's Visionscape machine vision software is very straight-forward, as is establishing an Ethernet connection between the two cameras.

The Visionscape job can be summarized as follows:

  • Camera 1. Search for and decode a 1D symbol using the Decode Tool.
  • Camera 1. If the symbol is found, then send a serial trigger "T" to Camera 2 using a Formatted Output step*. Also, send a Microscan Link command that saves the decoded text to the string1 slot in the Global Data Service to be retrieved by Camera 2 using a Formatted Output step" .
  • Camera 2. Start the programmed inspection at serial trigger " T."
  • Camera 2. Count objects in the Field of View using the Blob Tool.
  • Camera 2. Set an input datum that retrieves the decoded text via the Microscan Link string1 slot.
  • Camera 2. Send the result of the blob count and the decoded text as an output string using TCP/IP. This uses another Formatted Output step.

*The tool can be set to send, for example, to IP address 192.168.0.11 at port 49211, which is the IP address of a camera and the port where it expects the trigger.

" The text string sent to output would be: set string1 %s\n\r",Insp1.Snapshot1.SYMTool1.Text

Again, there is no need for an external PC or workstation to manage the communication of data between the two smart cameras. With Microscan Link, the inspection job can be programmed in advance to allow the cameras to perform complete PCB inspection independent of an external PC. Microscan Link enables countless applications similar to this one, with any number of tools, triggers, cameras, or other automation components networked or " linked" together to perform a number of tasks. The example of our customer's application described here is fairly basic, but a machine vision job like this could incorporate a far more complex execution of tools and triggers, perhaps conditioned by inspection results, and with more cameras linked into the machine vision network.

For more information about Microscan Link, I encourage you to check out these recent Microscan blog posts:

Or, watch virtual demos of our machine vision software AutoVISION and Visionscape in our Video Library.

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