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Webots Robot Simulator
https://cyberbotics.com
Apache License 2.0
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`CabinetDrawer` (mass distribution) design doubt #3649

Open ad-daniel opened 3 years ago

ad-daniel commented 3 years ago

Describe the Bug The CabinetDrawer PROTO appears to have a sphere as a boundingObject where the entirety of the mass of the drawer is concentrated. This despite each wood panel that comprises the Drawer being SolidBoxes (which have themselves Physics and a dummy masses of 0.01).

Does anybody know the reason for this Design? Why isn't instead the provided mass distributed across the SolidBox subnodes?

EDIT: same design in CabinetDoor

drawer

ShuffleWire commented 3 years ago

Maybe the author want to set a global mass for the whole object, and don't want to bother with splitting it in various sub mass. It allows to change easily the whole mass by a factor (for instance doubling the mass), by changing only one value, instead of individual change each of them, and ensure the sum of the sub mass equal the total desired mass. I still don't agree on this design, because it's not very physical, however. But in a PROTO, we could be able to automate the mass propagation in sub masses, imo.