[ODE] Wheel bending and a possible tweak
Michael Bickel
child at 3dactionplanet.com
Thu Dec 5 16:20:02 2002
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Hi,=20
I'm working with ODE for quite some time now.=20
First, Russ you have done a great job ! This lib is really unique.
We made it to include ODE into the Serious-Engine(www.seriousengine.com) =
via the official SDK.
For those who might wonder, the Serious-Engine is the engine behind the =
great fun game Serious Sam.
Of course, I have experienced the wheel bending problem too while I was =
toying around with=20
vehicles. A mate of mine came up with little tweak that solved( with a =
major trade-off) the bending for us.
This is how :=20
We simply lock both axis of all 4(speaking of a 4 wheel-vehicle) hinge2 =
joints to match the orientation of the chassis
before and after the Worldstep. This way the we wont suffer bending =
since nothing rotates. Then we apply forces
to the wheel bodies to *push* them forward. Then a little =
vector-calculation to take the steering angle in account and we get=20
pretty nice results.=20
This is really not the perfect solution, actually it's a weird hack, but =
it works once you tweak it a bit.=20
Now to proof that hacking can be a success (at least sometimes ;)) here =
is a 13 meg divx avi-file showing off ODE
and the result of the code in the mod of my friend.=20
http://www.jetti.org/cad/files/btba_trailer1.avi
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<DIV><FONT face=3DArial size=3D2>Hi, </FONT></DIV>
<DIV> </DIV>
<DIV><FONT face=3DArial size=3D2>I'm working with ODE for quite some =
time now.=20
</FONT></DIV>
<DIV><FONT face=3DArial size=3D2>First, Russ you have done a great =
job ! This=20
lib is really unique.</FONT></DIV>
<DIV><FONT face=3DArial size=3D2>We made it to include ODE into the=20
Serious-Engine(<A =
href=3D"http://www.seriousengine.com">www.seriousengine.com</A>)=20
via the official SDK.</FONT></DIV>
<DIV><FONT face=3DArial size=3D2>For those who might wonder, the =
Serious-Engine is=20
the engine behind the great fun game Serious Sam.</FONT></DIV>
<DIV> </DIV>
<DIV><FONT face=3DArial size=3D2>Of course, I have experienced the wheel =
bending=20
problem too while I was toying around with </FONT></DIV>
<DIV><FONT face=3DArial size=3D2>vehicles. A mate of mine came up with =
little tweak=20
that solved( with a major trade-off) the bending for us.</FONT></DIV>
<DIV> </DIV>
<DIV><FONT face=3DArial size=3D2>This is how : </FONT></DIV>
<DIV> </DIV>
<DIV><FONT face=3DArial size=3D2>We simply lock both axis of all =
4(speaking of=20
a 4 wheel-vehicle) hinge2 joints to match the orientation of the=20
chassis</FONT></DIV>
<DIV><FONT face=3DArial size=3D2>before and after the Worldstep. This =
way the we=20
wont suffer bending since nothing rotates. Then we apply =
forces</FONT></DIV>
<DIV><FONT face=3DArial size=3D2>to the wheel bodies to *push* them =
forward. Then a=20
little vector-calculation to take the steering angle in account and we =
get=20
</FONT></DIV>
<DIV><FONT face=3DArial size=3D2>pretty nice results. </FONT></DIV>
<DIV> </DIV>
<DIV><FONT face=3DArial size=3D2>This is really not the perfect =
solution, actually=20
it's a weird hack, but it works once you tweak it a bit. </FONT></DIV>
<DIV> </DIV>
<DIV><FONT face=3DArial size=3D2>Now to proof that hacking can be a =
success (at=20
least sometimes ;)) here is a 13 meg divx avi-file showing off =
ODE</FONT></DIV>
<DIV><FONT face=3DArial size=3D2>and the result of the code in the mod =
of my friend.=20
</FONT></DIV>
<DIV> </DIV>
<DIV><FONT face=3DArial size=3D2><A=20
href=3D"http://www.jetti.org/cad/files/btba_trailer1.avi">http://www.jett=
i.org/cad/files/btba_trailer1.avi</A></FONT></DIV></BODY></HTML>
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