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robotology / cer-sim

Official URDF and SDF models of the R1 humanoid robot.
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Procedure for changing the inertia of a link. #1

Open randaz81 opened 8 years ago

randaz81 commented 8 years ago

To improve the stability of the model, I had to modify the the inertia of few small dummy links in the .sdf. These changes will be lost next time the .sdf is regenerated from the CAD. It's not possibile to modify the inertia in the CAD, since it would change the shape of the dummy link. @fiorisi We thus need to modify the python script which converts the CAD model into the sdf file, allowing the user to assign an arbitrary inertia. @traversaro

traversaro commented 8 years ago

Option added in https://github.com/robotology/simmechanics-to-urdf/commit/c95e29afb517bf6a781cfa486bd1ed34460aed43 , now the configuration files need to be updated. A warning is printed if the assigned inertia is creating a non-physical inertia. Violating the triangle inequality should not be a problem in simulation, but could create problem with tools that assume that the inertia matrix respect this condition.