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 Post subject: Friction parameters of rigid bodiesPosted: Mon Jul 02, 2012 11:05 am

Joined: Wed Jun 27, 2012 9:13 am
Posts: 8
I have a next problem with the friction.
Here you can see an example video : http://www.youtube.com/watch?v=WEBTTwy-8aU

The robot tries to walk, fall down, and then he tries to stand up.
The friction of the bottom is 1 (body->setFriction(1)) and the friction of all robot parts is 0.9f .

Why he has no "foothold" , while he trying to stand up?

Does anybody can help me with it?

Thanks,
Oliver

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 Post subject: Re: Friction parameters of rigid bodiesPosted: Tue Jul 03, 2012 9:50 am

Joined: Tue Dec 25, 2007 1:06 pm
Posts: 347
Otz wrote:
The friction of the bottom is 1 (body->setFriction(1)) and the friction of all robot parts is 0.9f .
You can have a much bigger friction if you use the custom material callback, so that you can assign to the ground and to your robot's feet a friction much greater than one. However the dynamic behavior depends on many other variables (gravity, the mass/inertia of each robot part, the type/settings of the constraints you've used and so on). Furthermore, in the experiments I've made on this topic, I've never let the character fall: I've used a constraint (or an "angular factor") to keep it vertical when needed; so I don't really know if a 100% simulated robot like yours can really walk without falling (at least at 60 physic steps per second).

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