Closed loop control

  • Hi

    I'm trying to implement a closed loop controller that can perform live corrections. I want to improve the accuracy of the robot by using an external measurement system (laser tracker at the moment).

    Unfortunately I'm not sure what packages/software I need on the Fanuc or its controller (R-30iB).

    My ideal solution would look like this:

    1. I send cartesian point to the robot

    2. It moves there

    3. As it moves, I can adjust my desired position and the robot will move there


    I looked into the dynamic path modifier package but I'm not sure if I can build a controller with it, as I want to use the measurement data of the laser tracker and it doesn't look like the DPM package can communicate with external tools.

    Has anyone done something similar? I'm lost as soon as I look at all the packages from Fanuc.

  • AD
  • DPM is exactly what you want.


    How you want to deal with the sensor data is up to you. You will probably need to use it in conjunction with socket messaging to parse the data from the laser tracker. You would then use the parsed data to write to system variables.


    Conversely, you could manipulate the data with another external device and write it to an analog or group input.


    Your biggest limitation will be the update rate.


  • Thank you very much.

    What is the usual setup for this? Can I connect my PC via LAN to the Fanuc controller and send correction values from my PC? This would be nice, as the measurement system is connected to the PC and the PC receives the measurements.

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account
Sign up for a new account in our community. It's easy!
Register a new account
Sign in
Already have an account? Sign in here.
Sign in Now