Open itfanr opened 5 years ago
Any updates on this? I have also noticed there is an offset in the published velocities in Gazebo 9.
Hi @itfanr @sahandrez I think we are also seeing errors in rotational velocity since upgrading from Gazebo7 to Gazebo9.
I'm not sure if the bug is from Gazebo directly, or from code in "gazebo_ros_pkgs".
Can someone compare the output from Gazebo Vs. ROS ?
@itfanr it is a bit difficult to understand your post (above). Could you please label your graph plots with "applied force" or "output" or "gazebo" or "computed result" ?
@dbworth I donot have the image and the code now. Sorry about that.
I think that we encounter a similar issue. I described it in answers.gazebosim.org: https://answers.gazebosim.org/question/26191/ft-sensor-joint-velocity-and-joint-effort-readings-can-be-wrong/
In our case, the joint velocity and joint effort readings as well as the values from the FT sensor plugin are off close to singularities.
In case anyone wants to debug this, I'll post the code path for hinge joints:
This uses difference of body->avel
for the two bodies connected by joint. body->avel
is only written in the step functions:
So it really seems the velocities are a result of the physics computation. Now the question is why.
With
hardware_interface/EffortJointInterface
and gazebo7, I published the effort commands as follows:And I subscribed /joint_states and plot position and velocity line:
The line I got is:
But It seems the velocity is not currect. I caculated the velocity and got this:
Are there some error with these codes: