[GSoC] Planar Joint

[tjstienstra]

References to other Issues or PRs

Part of #21519

Brief description of what is fixed or changed

Implements the PlanarJoint

Other comments

Release Notes

• physics.mechanics
  • Added a PlanarJoint

[sympy-bot]

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• physics.mechanics
  • Added a PlanarJoint (#24046 by @TJStienstra)

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#### References to other Issues or PRs
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Part of #21519

#### Brief description of what is fixed or changed
Implements the PlanarJoint

#### Other comments


#### Release Notes

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* physics.mechanics
  * Added a PlanarJoint
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Update

The release notes on the wiki have been updated.

[sympy-bot]

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Hi, I am the SymPy bot (v167). I've noticed that some of your commits add or delete files. Since this is sometimes done unintentionally, I wanted to alert you about it.

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The following commits add new files:

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  • doc/src/modules/physics/mechanics/api/PlanarJoint.svg

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[tjstienstra]

@brocksam, @moorepants, @sidhu1012 FYI
This PR should be merged after #24037

[github-actions]

Benchmark results from GitHub Actions

Lower numbers are good, higher numbers are bad. A ratio less than 1
means a speed up and greater than 1 means a slowdown. Green lines
beginning with + are slowdowns (the PR is slower then master or
master is slower than the previous release). Red lines beginning
with - are speedups.

Significantly changed benchmark results (PR vs master)

Significantly changed benchmark results (master vs previous release)

       before           after         ratio
     [41d90958]       [f002fe53]
     <sympy-1.11.1^0>                 
-         987±2μs          632±1μs     0.64  solve.TimeSparseSystem.time_linear_eq_to_matrix(10)
-     2.82±0.01ms         1.18±0ms     0.42  solve.TimeSparseSystem.time_linear_eq_to_matrix(20)
-     5.67±0.02ms         1.72±0ms     0.30  solve.TimeSparseSystem.time_linear_eq_to_matrix(30)

Full benchmark results can be found as artifacts in GitHub Actions
(click on checks at the top of the PR).

[brocksam]

Looks like all combinations of possible user inputs are accounted for in the tests.

[tjstienstra]

@brocksam Just updated the set_vectors method as we discussed and also added a test of how I would do the example we discussed.

[moorepants]

There was some recent editing to the _compilation.py in #24059

[moorepants]

Can you update with master?

[tjstienstra]

Did a rebase to the master and squased my commits, so the commit tree is not as messy with all those small commits. Sorry for the mess of deleting and restoring the branch.

[tjstienstra]

After some discussing with @brocksam and @moorepants we came to the conclusion that it is best to leave the planar_vectors and rotation_axis arguments out for now. Since most of the time people will be defining the interframe anyways, so giving it as an extra option can be confusing. Besides that it is also better to not implement these unnecessary interface features for now, since they may make future more relevant development, like implementing constraints or efficient choice of generalized speeds, more difficult.

[moorepants]

Sounds good to me. Let me know when this one is ready and I can merge.

[brocksam]

Minor typo/punctuation suggestions. Once corrected this is ready to be merged.

[brocksam]

@moorepants, assuming that the tests still pass, this PR is ready for merging.