[ODE] systems flying apart at high angular velocities

[Gopi Prashanth]

I had the same problem. ODE solver works in a way that makes the angular
velocities diverge and without capping the angular velocity and
simultaneously damping it there is every possibility of a whole blow up. I
fixed this by doing it and worked fine after that. I did it in the
dxStepBody routine and it is not a huge expense.

Cheers,
Gopi

-----Original Message-----
From: Gary R. Van Sickle [mailto:g.r.vansickle at worldnet.att.net]
Sent: Tuesday, May 24, 2005 11:06 PM
To: 'ODE Mailing List'
Subject: RE: [ODE] systems flying apart at high angular velocities


> -----Original Message-----
> From: ode-bounces at q12.org [mailto:ode-bounces at q12.org] On 
> Behalf Of Graham Fyffe
> Sent: Tuesday, May 24, 2005 9:04 PM
> To: ODE Mailing List
> Subject: [ODE] systems flying apart at high angular velocities
> 
> Hey everyone.  I've got a joint rig set up for a car 
> suspension, and if I spin the car rather fast angularly, the 
> whole thing flies apart and a few frames later I get NaNs all 
> over the place.

Sounds like a class-action suit waiting to happen. ;-)

>  Is there any sensible way to keep a system 
> from flying apart under high velocities?
>  Thanks.
> 
> - Graham Fyffe

By explicitly constraining total system energy.  Somebody (sry, forget who,
it's in the list archives) has done this on top of ODE for freely-spinning
rigid bodies to keep them from infinitely "revving up" and detonating, but
not yet in the general case AFAIK.

-- 
Gary R. Van Sickle
 

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