Moho Forum

I try to make an object falling vertically down hang's in a string. I work owith bones but dont get it to work. Someone who understands what I mean and have a good solution?

grateful for the help

What exactly do you want? An object falling down? That's easy. An object on a string swinging from side to side? Easy as well.

an objekt falling straight down until the string stop it. just a little pendling. not a swing side to side. as if someone dropped the item straight down but but hould on the end of the rope. Like a medalion.


something like this but not the swing.
http://www.linslusenfilm.se/mellion.mov

OK, I bite. Here's my version of that:
http://www.slowtiger.de/examples/pendel.html

It's just an improvised movement, but within a planned setup. As you see in the file (http://www.slowtiger.de/examples/pendel.anme.zip), I had the string and the medal as separate layers, the medal was layer bound because it's rigid. The bone setup may look strange, but I did that on purpose. A chain of bones starts at the medal upwards along the string. From its root bone there's one bone for the medal. The origin point of that bone layer I set to the pivot point of the pendulum, the origin of the medal to its pivot as well.

I started animation with selecting all bones and create rotation and position keys, as well as a rotation key for the bone layer. This was the resting position of the pendulum, I pushed it to the end of the timeline and worked backwards from it.

First I created the overall pendulum swing. Using onion skinning for the extremes, I set each swing further outside than the last one.

Then I copied the resting position keys just one frame before the first swing extreme. I grabbed the root bone and translated its position, then did the same some frames before that to create the start oposition of the fall. The string of course became un-attached from its pivot point now. So I selected all bones minus medal bone and rotated them together - this way you get smooth curves in a chain. With careful rotating the root bone I was able to position the end of the string at the pivot point again. I repeated that for all frames within the medal fall. As you will notice, the end of the string isn't really fixed, but that doesn't matter, it looks good enough and could coverd somehow if the pivot point were visible. I fixed the medal rotation so it fell in nearly a straight line.

In the first swing I needed the medal to jump up again, so I repeated what I did in the last paragraph, only creating an S curve in the string, just for variety.

Since this looked nice, I created a swing of the medal alone, with its bone rotated a bit, but with a different frequency than the overall swing. Last thing I did was an oscillating medal layer scaling, again with a different frequency, to simulate the medal's turning at the end of the string.

As usual, a brilliant performance from you. I shall work on what futher will become a DVD menu.

Again, thank you so much.

My thanks as well for your sharing
your knowledge!

This is the work so far. I'm still not quite satisfied, but would i ever be?

http://www.linslusenfilm.se/cain.mov

You should tweak the first 5 frames a bit. Make it a smoother swing from side to side - it's a long chain and a heavy medal, so maybe 5 more frames are OK. Right now you have only 1 frame with the medal at the right side, which results in a jerky impression. If the eye can't follow the object because the path is too unpredictable, you destroy the illusion of movement.

Everything else is very fine.

I use the bone dynamics in the chain. but as you say, the perceived inflexibility. I'm working on ...

and thanks again.