Polyline slider goal

One topic that came up in recent workshops was how to attach a point to a polyline so that it stays on that polyline, and can slide from one segment to another.

Here is an example of a custom goal to do this. When you open it, you will need to change the referenced assembly location to your own local copy of KangarooSolver.dll

This can also be used to attach multiple polylines to each other in a sliding net, by attaching the same point to both.

Attachments:

PolylineSlider.gh, 14 KB

Replies to This Discussion

Permalink Reply by Jon on November 8, 2016 at 2:06am

Hi Daniel,

this custom goal seems works better than in Workshop! it helps a lot, thx again.

by the way, I have post a Topic last days regarding to penetration during the Origami-folding. maybe you will interest at it.

http://www.grasshopper3d.com/group/kangaroo/forum/topics/origami-10...

Permalink Reply by Daniel Piker on November 8, 2016 at 3:24am

Hi Jon,

Yes - I made a few improvements to the slider goal since then, such as making sure the point can't slide beyond the segment ends when the line is kinked.

I'll take a look now at the origami topic.

Permalink Reply by Jon on November 8, 2016 at 8:31am

Hi Daniel,

thx, it would be great if you could have a look about that Origami Topic coz it is a Kind of important key-issue for Folding-Problem and I do believe very Kangaroo fans are exciting to hear about that! ;-)

Permalink Reply by Jon on July 6, 2017 at 5:36am

Hi Daniel,

as Gregory Quinn demonstrated, that the cloth will be go back to its position (due to 'gravity')

The Node are sticky on the cable and able slide along it.

Sometime, in certain case, the free-slippery nodes are not allow, which means they should:

1. sticky on cable (like OnCurve),

2. slidably along cable, and

3. have some friction between Node and cable

For example, when the K2 solver activated, the node should stay where they are, and can be move along cable only by given force (pull or grab)

I have been tried using anchor xyz and plastic anchor, but both doesn't work fine and I guess this might not the right way to solve this issue because the cable is also movable in 3 dimensional and not rigid, which means the implementation of both anchor goals would change the static behavior of cable...

I was wondering if there are any elegant solution for this issue...I remember there are two feature in Kangaroo 1 called Static/ Kinetic Friction.

By the way, as you can see, the node of white-cable is shifted from node of black-cable. It is because of the prevention of typical numerous problem that the coincident points would sticky together. Just wondering if there is any other way to avoid it?

Permalink Reply by Daniel Piker on July 6, 2017 at 9:18am

Hi Jon,

I can't think of a way to do this with just existing goals. PlasticLength is almost what we need, but wouldn't work when the cable is not straight.

I think it would be possible though to combine the code from the PlasticLength goal with the Pulley to achieve this...

Permalink Reply by Jon on July 7, 2017 at 9:48am

Hi Daniel,

I was thinking what you mentioned about PlasticLength and try to figure out how to achieve this to solve the ''slippery-issue''.

Can you describe it more specifically? let’s assuming the cable is straight but inclined...well, which means we stay in the same slippery Problem ;-)

I found this discussion years ago: http://www.grasshopper3d.com/group/kangaroo/forum/topics/plasticity...

You are right, there is a huge potential to talk about this Topic…maybe you could add couple PlasticLength example (with a simple funicular…?) into Github Example Collection?

Permalink Reply by Gregory Quinn on November 11, 2016 at 8:44am