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Rail Compensation

I have a system where a robot arm is mounted on a rail. I have successfully completed RoboDK's calibration process for the robot. Since then, the rail compensation tool has been added to RoboDK (Utilities > Calibrate Robot). I would like to learn more about how it works and what I may expect/need when also performing the rail compensation.

1. I found this video for robot-only calibration: Is there a corresponding video that includes "Rail Compensation" as well?
2. What types of measurements will be required for "Rail Compensation"? I am still evaluating whether or not this would work well in my application, so I would like to see what will pop up in "Rail Compensation" and learn more about what is required without first completing "Base Setup" and "Tool Setup" just to see what it will suggest.
3. What type of compensation does the rail compensation apply? Is this just a lookup table that interpolates offsets in the robot base based on rail position? Or does it work more like Accurate Kinematics where it adjusts the kinematics based on the collected data?
4. Do the robot and rail data get interpreted together, or do they result in independently-applied compensations?

Attached Files Thumbnail(s)
To shcedule measurements for rail calibration you should use a script like this one:

It will schedule 3 measurements along thre rail using regular intervials between each 3 measurements.

When you click on Update with your robot calibration you have the option to click on Merge rail. This will make sure that robot compensation is applied after the rail compensation and both work as a bundle.

I attached a sample project (the turntable needs to be detached from the multi axis system to properly test robot calibration). Also, when you use the Merge rail option with the attached sample project it does not give good results here because we should have taken robot calibration measurements in the same area used to calibrate the rail.

There is no public video or documentation related to how to setup rail compensation. Rail compensation with RoboDK is a simple lookup table whic interpolates the pose of the robot base looking for the nearest points.

Attached Files
.rdk   LaserTracker-KUKA-KR500-External-Axes-Rail-50mm-steps.rdk (Size: 11.26 MB / Downloads: 28)

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