2 character interaction

Hi All:

I am brand spanking new to Blender. I downloaded about 4 weeks ago. I’ve gone thru several of the tutorials and I have a basic understanding of the process so far.

I am trying to use Blender animations to help students learn Judo techniques.

I followed the tutorial by Alimayo Arango to set up a low poly male figure and now have my 2 characters in a condition where I can start to do some of the techniques. I have also turned on the Physics module.

My problem is that in the areas where I set up “attachments” from one character to the other ( I made the arm of the White figure a child of the hand of the Red figure), the arm rigging separates from the shoulder as the animation progresses. The body mesh just acts like Gumby and stretches. In a later portion of the technique there is an interaction of the legs of the 2 characters. In this situation, the 2 legs just pass thru each other.

Does anyone have experience with interaction between 2 characters that may be helpful here?

Any suggestions would be appreciated.


Sensei Tom Palen

A rig, which controls the mesh, which controls what you see in a render, follows it’s own rules, not the rules you might expect from a physical representation of the object (in this case a manikin) you have created.

You’ll get more insight if you post your blend file, so people can take a look at your rig, but what is probably happening is that you have IK to keep the feet on the ground, and a child parent relationship between one character and the arm of the other. So, the IK holds the feet to the ground, the parent moves the arm to a physically impossible location, and the shoulder separates and the body stretches.

You’d need the White figure’s rig (the one being thrown?) set up as full body IK centered around the upper arm, and the ability to switch to that from the ordinary rig. When Red sweeps White’s legs out from under him, you’d need a similar changed rig so that the full body IK was now centered around White’s shin or thigh, and moved by Red’s leg…

For every different contact point on the body, you’d need a new rig. It might be quicker and easier to simply animate Red doing the throw move, then animating White to match Red’s movements. Still a tricky bit of animation to pull off.

You can post your blend file on PasteAll.org , so someone with a bit more experience in two character interactions (it’s pretty rare) can weigh in on your predicament.

Welcome to BlenderArtists :smiley:

I got the basic idea of what you described.
It sounds correct to me but I will have to dig for a while to understand it all.
I uploaded - TVP Osoto Gari animation 001.blend - to PasteAll as you suggested.
I was hoping that the mesh would provide the physical barrier needed to leverage one character around the other.
From what you are saying, the Physics package in Blender will not do that.
Am I incorrect about this?
I was hoping that Blender would provide the kinematics needed for this kind of work.

You can set meshes to ‘collision’ and they will interact with each other when you use the physics engine, but I don’t know how that interacts with animation, so I can’t really say if what you are trying to do is possible or not. Could you edit your post to provide a link? (That’s the icon between the happy face and the envelope over the reply window.)

Right now the file only exists on my personal PC. I do not have a website where I can load it.

I uploaded - TVP Osoto Gari animation 001.blend - to PasteAll as you suggested but I cannot figure out how to access it again on Pasteall.

I can send it as an attachment if that is permitted on this site. Or send it somewhere else.

I am not worried about outside access. 1st - it is intended for dissemination. 2nd - it’s not complete yet.

I also checked on my present version of the animation, I do have both the Rigid Body & the Collision option checked. No change.

What do I need to do to the main Bone (Shiro male - White) to allow the character to be unanchored?