KM.auxiliary

Peter Stahlecker

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Jun 19, 2021, 3:33:22 AM6/19/21

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I am playing around with this feature to get the forces acting on some point.

The result of KM.auxiliary_eqs contains (also) generalized accelerations.

I replace them with the relevant entries of KM.rhs().

This seems to work, but it gives BIG equations for even small problems.

Is this the correct way of doing it?

Is there a smarter way?

Thanks for any help!

Jason Moore

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Jun 19, 2021, 5:59:43 AM6/19/21

to sympy

Here is an example I worked on getting the contact forces for a bicycle tires using the aux equations:

https://github.com/moorepants/pydy/blob/bicycle-tire-constraint-forces/examples/bicycle_wheel_contact_constraint_forces/whipple.py

Here is a manual method of doing aux equations too: https://nbviewer.jupyter.org/github/moorepants/mae223/blob/master/content/lecture-notebooks/mae223-l19-01.ipynb, KanesMethod should make the same result.

Jason

moorepants.info
+01 530-601-9791

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Peter Stahlecker

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Jun 19, 2021, 6:07:15 AM6/19/21

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Thanks a lot for the prompt help!!

I will study it and I am sure it will help!

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