Recalculate the robtgt after changing the calib.

RobotStudio
1

Dear all,

I have a program done on 2 IRB2400 M98A with a wrong calibration. I fact I pointed this issue to my customer, but for timing reasons, I had no other choice that making my complete program with this calibration.

But meanwhile, the calibration has been set up, and I have to adjust my old program.

I?_Td like to know if it would be possible to recalculate the robtargets according to the new calibration, with RS?

I have the previous calibration values.

Thanks

2

In the RAPID tab, you will find the tool Adjust Robtargets. It is supposed to do exactly what you are asking for. It will recalculate the robtargets based changing the tooldata or workobject from the uncalibrated one, to the calibrated one. The robot will move along the same path (in the world coordinate system) after the operation.

The tool is available if you have a Premium license. Have you tried it?

3

Hello Henrik,

I don’t need to rebuilt this program yet, but only in a few days, so I don’t have try with the tool.
But I’m talking about a wrong calibration of the axis (2, 3 and 4) of the robot, and not only an uncalibrated tool.

Does the tool in RS support this?

4

Now I understand. But, unfortunately, the tool Adjust robtargets will not help you in this scenario. There is no standard RS tool that will help you in this particular case. However, I think there is a procedure you can go through to adjust your program.

  1. First you need to find out the joint error of the uncalibrated robot. You can, for instance, jog the robot to its sync position and read the (uncalibrated) current joint values of the FlexPendant. This is absolute necessary to establish a relation between the uncalibrated robot and the calibrated robot.

Example: Assume that the joint values of your uncalibrated robot in sync position are = [10, 23, 45, 30, -10, 98]

Note: All the values will be zero after calibration. If you have already calibrated your robot without checking the joint values before calibration you are lost. Then the procedure below will not work and you just need to redo the program.

  1. You need a custom version of your robot model. ABB may need to help you here. Please contact your local ABB Robotics Service representative. But you need to supply the joint values as desribed above. (Note that there might be a cost involved here for the work of creating the custom mechanism)

  2. create a system from a backup of the uncalibrated controller. (or use GoOffline)

  3. Load the backup, (not needed if you do Go Offline)

  4. Replace the RobotStudio standard mechansim with the custom mechanism created in step 2. (Use edit system)

  5. Step through the robot program from the RAPID editor or the Virtual FlexPendant.

  6. For each target, teach a new target or move instruction.

  7. When all targets have been re-teached, replace the robot model to the standard robotstudio model (=calibrated).

  8. Create a path with the modified positions.

  9. Sync to VC

  10. Done!

Puh!

Disclaimer: This procedure should work in theory, but has not been verified. There might be obstacles which I have foreseen that prevents this procedure from working.

5

Hi,

thanks for your reply.
Unfortunatelly, I was not present whilethe calibration, and they didn’t check the joint values. In addition the robots are not IRC5 but S4C.

I’m not sure that I will succed to apply your procedure!

:angry:

Thanks indeed.