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CentroEPiaggio / kuka-lwr

Software related to the KUKA LWR 4+: for real and for simulation.
The Unlicense
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Primitive PID tuning (MoveIt!) and FRI port number armonization #8

Closed marcoesposito1988 closed 9 years ago

marcoesposito1988 commented 9 years ago

Hi guys,

I managed to move the robot with MoveIt!, even for quite large movements and with a decent behavior. I guess it would be a nice starting point for more experienced people.

Btw, the port number in the KRL script in the repo is 49939, so I would suggest to use it as a default everywhere.

manuelbonilla commented 9 years ago

Hi @marcoesposito1988

Good work. Did you try using the PID controller with a fixed (and far from actual position) reference point? I think you are having a good performance for trajectories because moveit interpolate and thus you have always small errors. In the case you have a big errors the gains in the yalm file can be dangerous since they are big. @carlosjoserg I think we can add this as a warning in the README.

Tanks for contributing @marcoesposito1988

best

marcoesposito1988 commented 9 years ago

Hi @manuelbonilla ,

thanks! I played a bit more with it, and the high gains were indeed causing obscillations. This values should be an improvement.

I will continue working on it.

carlosjoserg commented 9 years ago

@marcoesposito1988 The mess you saw with the port number is because we have 2 arms with different port numbers, but thanks for the standardization, it is beneficial to understand the package.

I see you mdified the joint_limits.yaml file. You should know that these values are automatically generated from the URDF everytime the roslaunch lwr_moveit setup_assistant.launch is used (unless you avoid to overwrite that file explicitly). The parameter in the URDF model you should tweak to get the desired limit values is called <xacro:property name="velocity_scale" value="3"/>. I would recommend to use that, if you don't want this values to be overwritten accidentally with the MoveIt! setup.

@manuelbonilla The warning regarding the PID tunning is more or less there in the Overview section, would you check it to see whether it is enough or not.

The merge goes anyway, thanks again.

marcoesposito1988 commented 9 years ago

Hi @carlosjoserg ,

I didn't know that, thanks! I'll do that next. Thanks for merging!