Best ratio for RigidBodyControl

I want to have my CharacterControl player able to slide a RigidBodyControl chair across a RigidBodyControl hardwood floor with relative ease (and maybe knock the chair over). I know there are at least 3 factors related to this (spatial volume, mass, and friction).

What would be the best ratio of those 3 (and any other major factors) for the player, the chair, and the floor to achieve my objective?

I think it would depend a lot on the collision shape of the chair. Why not experiment and decide for yourself what works best?

well, answer is: there is no Ratio

friction - it depends on external material not volume/mass itself (mass will just multiple effect)
mass - it also depends based on “from what is it made?”
volume - no need tell.

for a chair, it will be 2-4kg ? idk. friction high, like 0.95

about floor similar friction.

I’m just confused about the numbers here.
What is the maximum mass? If I set my player mass to 2f, the chair will wiggle out from under the player, but if I set it less than that, it’s too difficult to move the chair.

Mass is effectively kilograms. Units are meters. Set values accordingly and then adjust as needed.

Probably your player has more than 2kg of mass, I guess.

Always start from real-ish values and then adjust to taste from there based on results.

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If I set the player mass to 5kg and the chair to 1kg, I end up “stepping” over the chair when I try to push it. When I try to jump onto the chair, the player gets stuck in the roof.

Edit: I’m not very good with kg’s, I’m better with lb’s :laughing:

Edit: I switched the chair mass to 3kg, and the problem seemed to get worse.

So your player is a very small dog? Or is it a person?

Edit: P.S.: I’m an American steeped in the rich and deep history of our really messed up ‘imperial’ system of measurement and even I know that the lb to kg conversion is 2.2… 1kg = 2.2 pounds, so roughly ‘double’ as a rule of thumb.

It’s an full-grown person, but if I increase the mass >=8, I end up fazing thru the roof at the start of the program.

“I messed up one physics problem because another physics problem was messed up.”

Start from real values. Fix the problems.

Else you will be chasing your tail forever and never get anywhere. Unless you are making a game of styrofoam objects and then the behavior is roughly as expected. Maybe that’s your answer: just texture everything white and pretend they are all made of lighweight foam?

Edit: re: “player mass > 10”… this is a picture of my dog:
She weights considerably less than she’d like to in this picture because she thinks she should have second dinner… but she weights ~34 kg.


The roof, walls, and floor are set to 0kg. I assume that’s the value you set for RigidBodyControl if you want it to be stationary but collide with stuff, because that’s how they did it in the tutorials.

I’ve set the player to 75kg, it still happens the same way as if I was at 10kg. As soon as my player hits the floor, he is teleported on top of the roof, where he can walk around just fine. When I switch to <8kg, the problem goes away.

I’ve also set all my furniture to about the right weights, but the problem still happens when I’m >7kg.

Nice dog! :smiley:

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Oof, I thought the step height parameter on the mass parameter… :expressionless:
Those errors are most annoying…

Thanks for the info on masses anyway.

sorry i dont read all, but based on first reply, seems like you have wrong "center of mass"

center of mass can be auto-calculated in Blender or other tools.