Applying physics in character armature

Hey everyone,

I happen to have a character made with makehuman laying on a box. Now I want the lower legs to swing downwards, bending at the knees. So I want to apply the physics engine to the armature.
I found out that applying rigid body physics to the body lets it move according to gravity (i.e.) as a whole only, no bending etc.

How can I accomplish this?
Thanks for the help, I wasn’t able to find suitable solutions on the net…


Why do you think you need to use the Physics Engine, when you can pose the character by simply moving the IK targets?

Cheers, Clock.

Well, I basically don’t want to position everything. I want to have the most physical look I can get…so why not use physics engine, I thought.
Is it impossible to apply physics engine to armatures?

I want to have the best real world look. So I want the dude to lie flat back on the cube and let the lower legs bounce.
Also maybe later I’d like to let him slip of the turned cube, that’s possible with rigid body physics.

Another thing is, how to model a mattress on top of the cube and below the guy.

Thanks for any help!


For the mattress I would create a simple cube, then stretch the sides out to the dimensions you want in Edit Mode, add a Sub-division Modifier set at 2 for render and view (also check “Optimal Display” checkbox), then add some edge loops (CTRL+R) and slide these near to the edges so you get the curves you want. You can then deform some the top faces to show a depression where the man lays, by lowering them in Z axis.

For the rig - you used Rigify to rig him right? just set Rigify to IK mode (In the left side menu 3D view) and drag the feet IK targets so the legs are bent as you want. I don’t have time today to post a blend file, so this will keep you going until I can spend a little time maybe tomorrow or Monday.

Cheers, Clock.

PS. There are no easy shortcuts in rigging and animation that will bring you good results!

Also, your post will take some time to appear as you are a new user, the first 10 are moderated.

OH, thanks for alle the hints.
So I honestly thought of having a soft body (the matress) that deformes according to physics and have the armature of the guy deforming according to physics. This doesn’t seem to be possible then?
As for the character, it is taken from Makehuman including the armature.
I sureley have IK bones at arms and legs, but still… my initial goal is to let physics do the job. My hope is to get natural looking results in the follow up animation.

Regarding the forum, thanks for the hint, so I only have to wait for next some posts. Good to know…didn’t know that.

There is a way for you to use physics but I’ve never really tried it out. I found some old files but it doesn’t work in 2.74 and 2.75. You will need a ragdoll tutorial. There is a way to bake the action so you will be able to keep the action. I usually suggest one but I haven’t really found the best one personally.