[ODE] movement force conversion

Jon Watte hplus-ode at mindcontrol.org
Wed Apr 6 11:38:59 MST 2005


The amotor will apply the same force on both bodies. Other things 
on those bodies, such as contact joints, may also apply force on 
the same bodies.

If you want to really closely follow the animation, you have to 
make joints higher up in the hierarchy (pelvis connected, spine, 
etc) have higher available force/torque than those further out, 
because they may potentially have to displace a whole lot more of 
connected mass. Of course with good (natural) animation, this 
will all balance itself out...

Cheers,

			/ h+


-----Original Message-----
From: ode-bounces at q12.org [mailto:ode-bounces at q12.org]On Behalf Of Piotr
Obrzut
Sent: Wednesday, April 06, 2005 10:58 AM
To: ode at q12.org
Subject: Re[12]: [ODE] movement force conversion


Hi Megan,

Sunday, April 3, 2005, 11:09:59 PM, you wrote:

MF> By taking your starting joint matrix, whatever it is (probably pose),
MF> and transforming it by your animation quaternion.  Then just extract
MF> the axis from the transformed joint matrix.

I remind that I was trying to control my dynamic model by
animations.

I think I did exactly as Megan sugested by setting apropriate AMotor
angles by euler angles taken from realtive bones orientations at each
animation frame. It looks exactly the same as in animation.

My question is: how setting amotor angle affect on forces acting on
both bodies? (I was trying to get this information from joint.cpp but
without succes).
While quick testing I think that this don't change bodies forces at
all or (more likely) it does but It doesn't care about external
forces - only main bone is following them (it is not affected by
angle setting function b/c it has no parent). The same situation was
when using setting joint vel function.

I was hoping that they will mix outside forces with this ones which tries
to set the apropriate angle (of course if such forces exists). Should
I calculate torques by myself instead (so I will be fully able to mix
forces)? I think also about some mechanism which will decrease the
animation weight on afected by collision and external forces bodies -
will this resolve my problem?

-- 
Greetings,
 Piotr Obrzut

_______________________________________________
ODE mailing list
ODE at q12.org
http://q12.org/mailman/listinfo/ode




More information about the ODE mailing list