Modelling a rope pulling up a load in a pulley

[Akash Vardhan]

Hi, I wanted to model a pulley like contraption where a load was being pulled up by a rope, by  applying a torque to the other end as shown in the cartoon attached here.

How would I model a rope like element in Chrono, could you point me to some example codes?

Best,

Akash.

Georgia Institute of Technology

[Dario Mangoni]

Hi Akash,
one of the [latest commits](https://github.com/projectchrono/chrono/commit/04e39e2e3b9129533294a23293ebf84e8d9f9473) to Chrono added new operating modes to the ChLinkDistance, introducing also a unilateral constraining mode.
This allows to model a simple rope without introducing bodies to the simulation.

We also tried to add some pulley and reel, but it's not that trivial and it would require some proper effort.

Moreover, ChLinkDistance is not exactly meant to have a varying length, thus potentially introducing some instability in the model.

As it is right now we can just provide some trivial example: in the attachment a starting code and the relative animation. The reel is still not working.
Please mind that is a crap code, made just for fun, and that it requires the very latest commit of main branch!

Dario