Grasshopper
Kangaroo
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Kangaroo is a Live Physics engine for interactive simulation, optimization and form-finding directly within Grasshopper.
pulley_block and tackle system
I notice that some years ago many people are following a very interesting topic about pulley-simulation. So far I know this component is not released in kangaroo yet.
http://www.grasshopper3d.com/forum/topics/pulley
I have tried using physics rule (with some kangaroo force-components, e.g. collideMesh...etc.) and geometrically approach to solve it. But it doesn't work appropriate.
There are some problems to be bear in mind, e.g. the mechanical properties of rove and friction over the pulley, namely how to transmit a tension force around one or more pulleys...etc.
It seems a pretty tough problem! do you have any elegant hint to solve this interesting mechanisms?
Daniel Piker
Hi Frank,
I actually did some work on this recently.
Attached is a definition containing a scripted custom goal which preserves the total length of 2 segments.
This can be used to simulate an idealized pulley where the cable turns at a point.
The next step (which I've not tried yet, but think should be possible) is to extend this to work not just with 2 segments, but over a polyline of many segments.
Alternatively, if you do actually want to model the radius of the pulley, there might be an alternative approach involving collisions that I'll post in a moment.
Feb 16, 2016