Hello, I played with Gazebo 0.7 some time back and recall that when creating models everything was based off of some point. I used my vehicle's center of rotation and this made for a relatively logical layout.
Now I'm trying to create a similar model in Gazebo 0.8/SVN and running into some trouble. It seems that when creating one body with multiple geometries that the (0, 0, 0) point must be the center of geometry, rather than some arbitrary point (such as center of rotation), like you could do in code for Gazebo 0.7. This is still manageable and somewhat logical, though it can be annoying to dimension a vehicle based off the center of geometry. But then came time to place the wheels. It seems that when placing a body relative to another body, the XYZ coordinates must be in relate to the center of _mass_ of the bodies. For simple objects this okay, as it will be the same as the center of geometry. But if you have a vehicle with an uneven weight distribution, not only would you have to find the center of mass to determine the wheel location (very awkward, but doable) but you also would need to modify the wheel locations if you change the weight distribution, which does not make sense. Is this the setup merely because of ease of implementation, or is there reason behind it? I'm completely new to the Gazebo 0.8 codebase, but I'm willing to spend some time trying to make it a bit more logical to create models if a patch changing this would be accepted. Thanks for the information, -Kevin For those interested a simple model to test this with can be found at the link below. Run it and note the wheel locations (Turn on Bounding Box). Then change the mass of box1 and box2 and notice the wheels new location. http://es.udmercy.edu/~barryke/boxtest.model ------------------------------------------------------------------------- This SF.net email is sponsored by: Microsoft Defy all challenges. Microsoft(R) Visual Studio 2008. http://clk.atdmt.com/MRT/go/vse0120000070mrt/direct/01/ _______________________________________________ Playerstage-gazebo mailing list [email protected] https://lists.sourceforge.net/lists/listinfo/playerstage-gazebo
