IiwaDriver: Create controller MBP from scenario file

[siddancha]

Fixes #316

• Create the controller plant for the IiwaDriver by reusing the user-provided scenario, instead of creating a custom iiwa (hardcoded to iiwa7) and the WSG schunk.
• This is enabled by being able to freeze child instances i.e. removing non-weld joints in the child instance and replacing them with weld joints. This is in-turn made possible by this recently landed PR: ([multibody] Adds RemoveJoint() RobotLocomotion/drake#21397)

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This change is 

[siddancha]

There is currently an issue with plant.GetJointActuatorIndices(child_instance) that returns an empty list. Therefore, the actuators aren't actually removed in:

# remove joint actuators
for actuator_index in plant.GetJointActuatorIndices(child_instance):  # list is empty
    actuator = plant.get_joint_actuator(actuator_index)
    plant.RemoveJointActuator(actuator)

I needed to explicitly add the following to get it to work locally:

for actuator in [
        plant.GetJointActuatorByName('left_finger_sliding_joint', child_instance),
        plant.GetJointActuatorByName('right_finger_sliding_joint', child_instance)
    ]:
    plant.RemoveJointActuator(actuator)

Seems like a potential bug MultibodyPlant::GetJointActuatorIndices(child_instance), and is what is causing the tests to fail. Will dig into this and potentially raise an issue on the drake's Github.

[siddancha]

Added GetJointActuatorIndices bug report and a simple reproduction here: RobotLocomotion/drake#21547

[siddancha]

Realized from bug report (RobotLocomotion/drake#21547) that GetJointActuatorIndices(model_instance) cannot be used pre-finalize. Using @jwnimmer-tri 's solution to call plant.GetJointActuatorIndices() and remove the actuators corresponding to the joints to be removed.

[RussTedrake]

thanks! ironically, i already did all this in https://github.com/RussTedrake/manipulation/blob/master/book/mobile/exercises/mobile_base_ik.ipynb
will review this morning.

[RussTedrake]

one small request. otherwise LGTM. Thanks!

Reviewed 2 of 2 files at r3, all commit messages.
Reviewable status: all files reviewed, 1 unresolved discussion (waiting on @siddancha)

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manipulation/station.py line 395 at r3 (raw file):

        frame_on_child = joint.frame_on_child()
        plant.RemoveJoint(joint)
        plant.WeldFrames(frame_on_parent, frame_on_child)

per my mobile_ik example, I preferred the extra line using the WeldJoint constructor so that I could keep the joint name the same.

Also, if there are mimic joints anywhere in the model, this will throw. But I think that's ok for now.

[siddancha]

Reviewable status: 1 of 2 files reviewed, 1 unresolved discussion (waiting on @RussTedrake)

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manipulation/station.py line 395 at r3 (raw file):

Previously, RussTedrake (Russ Tedrake) wrote…

per my mobile_ik example, I preferred the extra line using the WeldJoint constructor so that I could keep the joint name the same.

Also, if there are mimic joints anywhere in the model, this will throw. But I think that's ok for now.

Makes sense! I just switched to the WeldJoint constructor.

[RussTedrake]

Reviewed 1 of 1 files at r4, all commit messages.
Reviewable status: all files reviewed, 1 unresolved discussion (waiting on @siddancha)

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pyproject.toml line 5 at r4 (raw file):

# Use e.g. 2023.10.4.rc0 if I need to release a release candidate.
# Use e.g. 2023.10.4.post1 if I need to rerelease on the same day.
version = "2024.06.07"

btw -- i presume that this means you would like me to roll some pip wheels once this lands?

[siddancha]

Reviewable status: all files reviewed, 1 unresolved discussion

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pyproject.toml line 5 at r4 (raw file):

Previously, RussTedrake (Russ Tedrake) wrote…

btw -- i presume that this means you would like me to roll some pip wheels once this lands?

If it's not a hassle/concern? Otherwise I can just also do pip install git+https://github.com/RussTedrake/manipulation@master and not rely on PyPI releases.

[RussTedrake]

pyproject.toml line 5 at r4 (raw file):

Previously, siddancha (Siddharth Ancha) wrote…

If it's not a hassle/concern? Otherwise I can just also do pip install git+https://github.com/RussTedrake/manipulation@master and not rely on PyPI releases.

Done. (i've pushed to pypi)

[siddancha]

Reviewable status: complete! all files reviewed, all discussions resolved

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pyproject.toml line 5 at r4 (raw file):

Previously, RussTedrake (Russ Tedrake) wrote…

Done. (i've pushed to pypi)

Thank you!