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Inertia value does not match the box size
'pybullet_examples/inverse_dynamics.py' relates to the urdf file 'pybullet_data/TwoJointRobot_wo_fixedJoints.urdf'. In the urdf,
<link name="link_1">
<visual>
<geometry>
<box size="1.0 0.1 0.05"/>
</geometry>
<origin rpy="0 0 0" xyz="0.5 0 0"/>
<material name="blue"/>
</visual>
<collision>
<geometry>
<box size="1.0 0.1 0.05"/>
</geometry>
<origin rpy="0 0 0" xyz="0.5 0 0"/>
</collision>
<inertial>
<mass value="0.5"/>
<inertia ixx="0.00208333333333" ixy="0.0125" ixz="0.00625" iyy="0.167083333333" iyz="0.000625" izz="0.168333333333"/>
</inertial>
According to the formula for the inertia tensor of a rectangular body: ixx=(1/12) * 0.5 * (0.1*0.1+0.05*0.05)=0.0005208, and ixz, ixy, iyz =0. Why are the results does not match with <inertia ixx="0.00208333333333" ixy="0.0125" ixz="0.00625" iyy="0.167083333333" iyz="0.000625" izz="0.168333333333"/>