Add material on collisions

[moorepants]

I need at least an example on setting up the momentum balance to find pre and post velocities of a multibody system.

[moorepants]

This should include a simulation that shows how you switch between states before and after the collision.

[moorepants]

We decided not to include this chapter for the 2023 offering: moorepants/me41055#60

[moorepants]

Might be a nice resource: https://www.sciencedirect.com/science/article/pii/S0094114X23000782

[Peter230655]

This should include a simulation that shows how you switch between states before and after the collision.
Do you have something in mind like 'my' Newton's pendulum, but the collisions not modeled continuously like I have done (I learned this term in the article you just posted the link to), but with the inpulse balance, as described in the article?

This article is good, and not too hard to read!

[moorepants]

I want to show the Newtonian solution for momentum balance before and after a collision with a coefficient of restitution for a multibody system as a basic way to deal with collision and then probably a Hunt-Crossley force model. That would give two starting ways to deal with impact.

[Peter230655]

Do you mean the law as given in the first line of table 1 (below equation (64) of this publication, I mean the 'nice resourse' mentioned above?

If correct, I could try to play around with my Newton' s pendulum.

[Peter230655]

I tried to modify my Newton's pendulum using the Hunt-Crossley force model.
It works fine, if the pendulum consists of two bodies only.
For more than two bodies, I could only get the Hertz limiting case ( $c_\tau = 1.$ ) to work satisfactorily.
As I cannot attach my program here, they do not accept such files, I send it to Timo and Jason by separate email.

[moorepants]

The force chapter has been improved to show Hunt-Crossley model properly. Would still be nice to have the Newton approach somewhere.