How to model a Bullwhip with physics, that can follow the character movement

Hey guys,

For a couple of days I’m trying to think of the method of how to create a bullwhip (as a weapon) for my character animation, that will follow his motion. I would animate it manually, but there are too many actions to be animated and I’m already running out of time. It also has to be rigged, as I need it in a coiled position to attach it on a character’s belt (I’m gonna use a pose library for this action). Anyway, I’ve tried several things out, but without any satisfying result and I’m actually getting seriously worried about it.

  1. I don’t want to create it from a curve like shown in this video ( https://www.youtube.com/watch?v=4ANT5vf5H-Y ), because then the curve shape will have the same thickness and it will look more like a rope or a wire rather than a whip.

  2. I’ve also found this video ( https://www.youtube.com/watch?v=O3pxknjexEI ), which can give some significant results, but even though I’m following every step made in this tutorial, I’m getting a different result - my mesh behaves like an actual cloth, it is getting flat, distorted, changes its thickness in several places. In some cases it inflates like a balloon or moves to slowly etc. Maybe I’ve missed something, 'cause there’s no sound in this tutorial and the speed is very high… If someone knows how to keep the initial shape of the mesh during the cloth simulation it will help a lot, because I already tried almost all combinations of settings and values there.

  3. I’ve even tried to use the rigid body method ( https://www.youtube.com/watch?v=nHVYYMG3QVY ). I’ve created some kind of chain shapes and connected them with a rigid body simulation and turned on the “animated” option. I’ve added rigid body constraints (fixed type) to all of the chains to disable the “breakable” option. I then added these objects to an armature and made this armature the child of my character rig (from an object constraints.) After I play the animation, the chain follows the hand, but rigid body physics doesn’t work anymore and its stiff like a firewood. What could be the problem?

Please give me some advice either from these 2 methods to be solved, or maybe u know some other way to make want I need… Thanks

You can use the curve method, and use a Taper Object to deform the extruded curve.

taper_test.blend (440 KB)

A curve could have multiple thicknesses. Each vertex has a Radius parameter that controls the thickness of the extrusion.

I think a whip may be one of those times when it’s quicker to key-frame animate than to get all the physics and the arm-movement exactly right. Making a cloth-sim whip crack sounds nearly imposable.

You could fade in and out the physics (and the armature) in the modifier properties, though.

Thanks guys! I’ll try to use the curve method. I just can’t find a vertex radius parameter you are talking about.

Yes Yogyog, I keep in mind the key-frame animation as the plan B that will work for sure. Though, in my case that’s a hell of a lot of work and I really wanna be sure that manual method of key-frame animation was the only way I could do it.
P.S. What do u mean in fading in and out the physics and the armature? Key-framing its settings through the modifier properties?

yogyog where in the ui would i go to fade a physics simulation in and fade it out?