Disable j23_coupled for robots without parallel arm linkage

[cjue]

This PR builds upon #137.

Without this commit some support packages have J23_coupled enabled, some disabled.

To my knowledge however this would be an application specific setting that should match the robot controller configuration, and should rather be uniform between the support packages to avoid confusion.

J23_coupled = false matches the expected behavior for a generic 6-axis robot.

Do I misunderstand something that speaks against setting this to false in general?

[gavanderhoorn]

Do I misunderstand something that speaks against setting this to false in general?

in my experience, the coupling is not application specific, but robot model/variant specific.

I've worked with controllers which had it set for their robot(s), and with controllers without it.

I trust the values we currently have set as default are correct. If they aren't, they should be fixed.

Without some documentation to back up your claim it's application specific, I'm hesitant to change a default in the way you propose.

[gavanderhoorn]

Friendly ping here as well @cjue.

[cjue]

Do I misunderstand something that speaks against setting this to false in general?

in my experience, the coupling is not application specific, but robot model/variant specific.

You are correct, I was confused by misreading part of the datasheet and the mismatch between the previous irb1600 default of J23_coupled = true. The setting is not application specific.

To my understanding models with external parallel arms like the IRB 6660 [1] should have the J23_coupled setting enabled, and robots without the external structure like the IRB 1200 [2] and 1600 [3] should have it disabled.

As I see it a lot of the robots in this repo have the wrong setting, for example the IRB1600.
We had to set the J23_coupled setting to false to be able to correctly operate the IRB1600 we were working on.

Overview of models: https://new.abb.com/products/robotics/industrial-robots/irb-1600

• [1] https://new.abb.com/products/3HAC020536-013/irb-6660
• [2] https://new.abb.com/products/robotics/industrial-robots/irb-1200
• [3] https://new.abb.com/products/robotics/industrial-robots/irb-1600

[cjue]

I went over the list of all robots supported by abb_experimental and cross-checked their J23_coupled settings with their design documents.

If I did not miss something models with parallel arm linkage would be irb2400, 4400, 7700, 8700, 6660, 260, 460, 660, 760.
These all don't have support packages in abb_experimental.

The models irb1600, 6650s, 6700, 7600 and irb52 all don't have parallel arm linkage and therefore should have the J23_coupled setting disabled like the remaining models in this repository.

It appears to me, that the mistake arose when the IRB2400 model from the abb repo was used as a template for all following launch files, and that model does have J23_coupled correctly enabled.

[cjue]

Note: if #137 is merged first, the irb1600 10/1.45 also needs to be modified.