Symmetrical Legs have different behaviours

asked 2022-07-20 08:02:36 -0500

Hi everyone. Im working on a URDF of two bipedal robot. Ive noticed that the two legs have not a symmetrical behaviours after the joint limit is reached. In order to debug the urdf model, I rewrite only a fixed base with 2 symmetric links.

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I report also the plots of the velocity joints and position joints.

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As you can see, when the joint angle reach limit, the velocity change instantaneously value and sign, as expected. In theory:

v(k+1) = -b*v(k) where b is a number in the range of 0 and 1.

As you can see from the velocity plots (green and purple line), the "b" constant is different between left and right leg. What is this parameter in gazebo and why the default value is different between legs?

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