Composite object vs. tri-mesh question

Brett Hemes <[email protected]> Wed, 14 Nov 2007 12:04:08 -0600
Newsgroups gmane.comp.lib.ode
Message-ID <[email protected]>
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Hello,

I am learning ODE for use in robotics simulations for research and  
have a couple of questions regarding geoms and collisions.  I have to  
represent a trapezoidal prism-shaped mobile robot that can rotate on  
all three of its axes.  I recall reading somewhere that dynamic tri- 
meshs are less desirable than composite objects made from  
primitives.  If I try and build a nice trapezoidal prism from boxes  
however, I have geometries that share surfaces that commonly collide  
with other geoms (another thing I read is bad).  Is there any  
generally accepted answer for this problem?  I am currently using the  
composite object approach and have yet to see any stability problems  
in version 0.9 with double precision but I would like to know if this  
is a hack.

Additionally, is it common/possible to have geoms in different spaces  
attached to the same body where one space is used for collision  
detection and the other for drawing the output?

Thanks,
Brett





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<HTML><BODY style=3D"word-wrap: break-word; -khtml-nbsp-mode: space; =
-khtml-line-break: after-white-space; "><DIV>Hello,</DIV><DIV><BR =
class=3D"khtml-block-placeholder"></DIV><DIV>I am learning ODE for use =
in robotics simulations for research and have a couple of questions =
regarding geoms and collisions.=A0 I have to represent a trapezoidal =
prism-shaped mobile robot that can rotate on all three of its axes.=A0 I =
recall reading somewhere that dynamic tri-meshs are less desirable than =
composite objects made from primitives.=A0 If I try and build a nice =
trapezoidal prism from boxes however, I have geometries that share =
surfaces that commonly collide with other geoms (another thing I read is =
bad).=A0 Is there any generally accepted answer for this problem?=A0 I =
am currently using the composite object approach and have yet to see any =
stability problems in version 0.9 with double precision but I would like =
to know if this is a hack.</DIV><DIV><BR =
class=3D"khtml-block-placeholder"></DIV><DIV>Additionally, is it =
common/possible to have geoms in different spaces attached to the same =
body where one space is used for collision detection and the other for =
drawing the output?</DIV><DIV><BR =
class=3D"khtml-block-placeholder"></DIV><DIV>Thanks,</DIV><DIV>Brett</DIV>=
<DIV><DIV><SPAN class=3D"Apple-style-span" style=3D"border-collapse: =
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</DIV><BR></DIV></BODY></HTML>=

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