Add whole-body differential IK example

[sea-bass]

This PR adds a joint_weights option to differential IK, which can be used for e.g. solving whole-body IK.

Incidentally, I also had to fix how the "ignore joints" works, meaning we're now doing it better. Meaning now we grab only the columns of the Jacobian we need instead of doing the full calculation and throwing away unneeded output.

It also adds a UR5 on mobile base URDF and cleans up all the models in the package to be in the same location. (this is where most of the deletions come from)

python3 examples/differential_ik_whole_body.py

Closes #52

[github-actions]

Coverage Report

File	Stmts	Miss	Cover	Missing
pyroboplan
__init__.py	0	0	100%
pyroboplan/core
__init__.py	0	0	100%
planning_context.py	8	8	0%	1, 4, 9, 13–15, 17–18
utils.py	134	12	91%	78–79, 81–84, 86–87, 228–229, 531, 542
pyroboplan/ik
__init__.py	0	0	100%
differential_ik.py	110	14	87%	193–194, 203–204, 232, 238, 244, 247, 293–294, 297–298, 303, 314
nullspace_components.py	35	0	100%
pyroboplan/models
__init__.py	0	0	100%
panda.py	45	0	100%
two_dof.py	25	13	48%	41, 47–49, 51, 57–59, 62, 65–68
ur5.py	15	15	0%	3–4, 6, 9, 18–20, 22, 25, 41–44, 46–47
utils.py	5	0	100%
pyroboplan/planning
__init__.py	0	0	100%
cartesian_planner.py	92	5	94%	115, 139, 143–144, 207
graph.py	130	4	96%	58, 103, 195, 261
graph_search.py	53	2	96%	57, 135
path_shortcutting.py	48	1	97%	121
prm.py	109	25	77%	113, 149, 211–214, 240–241, 247–248, 273–274, 278–279, 331–334, 337, 340, 348–350, 354–355
rrt.py	152	28	81%	157–158, 167–168, 192–193, 196, 204, 273, 302–303, 369, 417–419, 423–424, 428–431, 434, 437, 445–447, 450, 453
utils.py	47	0	100%
pyroboplan/trajectory
__init__.py	0	0	100%
polynomial.py	152	39	74%	148, 150–151, 153–155, 157–159, 162–185, 188, 191, 194, 203, 230, 299
trajectory_optimization.py	183	0	100%
trapezoidal_velocity.py	168	33	80%	283–284, 329, 331–335, 337–338, 341–359, 362–364, 373
pyroboplan/visualization
__init__.py	0	0	100%
meshcat_utils.py	21	13	38%	40–41, 43, 45, 57, 81–82, 109, 131–134, 136
TOTAL	1532	212	86%

Tests	Skipped	Failures	Errors	Time
97	0 💤	0 ❌	0 🔥	30.034s ⏱️

[sea-bass]

One internal debate I am having is whether this qualifies as "whole body IK" or I should relax some of the claims and use something like mobile base, floating base, etc.

[eholum]

I think whole body is appropriate given a very quick googling of where the term is used!

Just some minor questions but overall this is pretty nifty. Plus it's so fun to watch the entire robot run off into the distance when the solution diverges.

[eholum]

👍👍👍