PLC Workflow

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Supported Controllers

• Rockwell CompactLogix controllers
• Rockwell ControlLogix controllers
• Controllers that use the Open Platform Communications Unified Architecture (OPC UA) protocol

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Set Up Inspection Points for PLCs

1. Create an Inspection Point.
2. Select your Image Source.If you want the PLC to trigger the inspection start and you are capturing images with a connected industrial camera, select GigE Vision Camera or GenICam and then select your camera.
3. Select your Inspection Start method.If using an industrial camera, select PLC. Make sure you configure your PLC to start inspections. This will vary based on your PLC device.
4. Set up the Cloud Connection and Modelsettings.
5. Complete the following steps in the Communication section.
6. Select your PLC Type.
7. Enter the IP address of the controller in the Address field.
   • For Rockwell controllers, use this format: [IP Address]/[Slot Number].Example: 192.168.1.5/0. (If there’s no slot number, omit it.)
   • For OPC UA controllers, use this format: opc.tcp://[IP Address]:4840.Example: opc.tcp://192.168.1.10:4840.
8. Click Set to set up the Inputs and Outputs, which are the data points that LandingEdge and the PLC can share with each other.
9. Click Add New Signal.
10. Select an option from the Signal drop-down menu. For detailed information about the options, go to Inputs and Outputs.
11. If you selected Custom, enter the Name and Data Type.If you selected an existing signal type, these fields auto-populate and can’t be changed.
12. Enter the PLC Tag or Tag Address in the Tag/Address field for that data point. This field isn’t case-sensitive. For information about how to program your PLC, refer to the device manufacturer’s documentation.For example, the images below show the signals in the PLC application and the matching signals in LandingEdge:
13. After you’ve set up all the signals, click Set Inputs & Outputs.
14. Confirm that the Communication panel shows the number of signals you’ve set up.
15. (Optional) Set up Image Saving settings.
16. (Optional) Set up Other Settings settings.
17. (Optional) Set up Custom Processing.

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Inputs

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Outputs

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Test Inputs and Outputs

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Example Setup of LandingEdge and a PLC

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Example Workflow

1. LandingEdge indicates that it is Online.
2. LandingEdge is ready and asserts Trigger Ready (True).
3. The PLC asserts Trigger (True) based on the set configurations. LandingEdge receives this signal and recognizes it is time to take an image.
4. LandingEdge changes Trigger Ready to False. The PLC receives this signal and recognizes that LandingEdge acknowledged the Trigger.
5. LandingEdge asserts Busy (True) to indicate that it cannot be triggered again. The PLC can monitor this signal.
6. After LandingEdge has received and processed an image, Result OK is set to True and Result NG is set to False.
   • If using a Classification model, Classification is set to the predicted Class ID.
   • If an error occurs, Error is set to True.
7. After the Results are set, LandingEdge asserts Results Ready (True) to indicate that results are available for the PLC to read.
8. The PLC recognizes that Results Ready or Error is set to True. It reads the appropriate values—like Results OK , Results NG, and Classification—to determine the final prediction from the model.
9. After the PLC reads the results, it asserts Results Ack. LandingEdge receives this signal and recognizes that the PLC has read the results and the cycle is complete.
10. LandingEdge resets the result signals and is ready to initiate the cycle again (starting from step 2).

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Sample Script: Read Inputs and Write Outputs

• ReadInput: Save inferenced images to directories and filenames based on custom signals defined in the Inputs and Outputs.
• WriteOutput: Send the X and Y coordinates of bounding boxes of predicted objects to the PLC (applicable when using an Object Detection model).

• lot: This is the lot number for a set of products, and is defined in the PLC.
• batch: This is the batch number for a set of products, and is defined in the PLC.
• x: This is the x coordinate of the bounding box for a predicted object of interest.
• y: This is the y coordinate of the bounding box for a predicted object of interest.

public void Run()
{
    // Read inputs for the lot and batch signals from the PLC; the arguments must match the signal names defined in LandingEdge ("lot" & "batch")
    var lotName = ReadInput("lot");
    var batchName = ReadInput("batch");

    // Save images to custom directories & filenames; these override any other settings
    Data.SaveResultsPath = $@"d:\productionImages\{lotName}\{batchName}";
    Data.SaveResultsFilename=$"{lotName}.png";

    // Send the X & Y coordinates to the PLC
    WriteOutput("x", 123.456);
    WriteOutput("y", 789.123);
}

def run(self):
    # Read inputs for lot and batch from the PLC; the arguments must match the signal names defined in LandingEdge ("lot" & "batch")
    lot_name = self.ReadInput("lot")
    batch_name = self.ReadInput("batch")

    # Save images to custom directories & filenames; these override any other settings
    self.Data.SaveResultsPath = rf"d:\productionImages\{lot_name}\{batch_name}"
    self.Data.SaveResultsFilename = f"{lot_name}.png"
    
    # Send the X & Y coordinates to the PLC
    self.WriteOutput("x", 123.456)
    self.WriteOutput("y", 789.123)

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Results Processing Considerations