Fix appendModel issue when a frame have non null transformation

[jorisv]

Description

When a frame have inertia and a non null transformation, appendModel algorithm was doing some wrong computation to compute joint inertia of the new transform.

Close #2805

TODO

• Fix AppendJointOfModelAlgoTpl
• Fix appendUniverseToModel
• Check if there is an issue with eometry

Checklist

• I have run pre-commit run --all-files or pixi run lint
• I have performed a self-review of my own code
• I have commented my code where necessary
• I have made corresponding changes to the doxygen documentation
• I have added tests that prove my fix or feature works
• I have updated the CHANGELOG or added the "no changelog" label if it's a CI-related issue
• I have updated the README credits section

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[martisalcedo7]

Shouldn't this be changed as well in the appendUniverseToModel() method?

[jorisv]

@martisalcedo7 I'm currently looking at it but frame with inertia attached to universe is kind of weird. Do you see an use case of it ?

[martisalcedo7]

@martisalcedo7 I'm currently looking at it but frame with inertia attached to universe is kind of weird. Do you see an use case of it ?

It is weird but it can be there. We have to make sure this inertia is not given to the body with addFrame(), therefore the argument append_inertia should be set to false.

[jorisv]

Ok, after discussion it can model the inertia of the base of a manipulator.

[martisalcedo7]

Can we also apply the fix here for the geometric bodies?

They are expressed with respect to the frames, not with respect to the joints, so this transformation is wrong. It was also shown in the issue.

In the function appendUniverseToModel()

go.placement = (pframe.placement * pfMAB) * go.placement;

[jorisv]

As said in the issue I'm waiting to have an example to reproduce it.

[martisalcedo7]

As said in the issue I'm waiting to have an example to reproduce it.

I am working on that.

[martisalcedo7]

It was a bug in our side. Please omit this geometry problem.

[JTem]

i also confirm, ignore the geometry issue