Ros_messages raw data for velocity about abb HOT 9 CLOSED

I'm not quite sure I understand what you're trying to do. Could you elaborate a bit?

from abb.

Are you asking why message.velocity is not populated?

from abb.

Yes I'm asking why message.velocity is not populated and how to do so ?

from abb.

Did you add this line:

UnpackRawBytes raw_message.data, 29, message.velocity, \Float4;

Because I can't find it in the current version (and it's also not going to result in correct deserialisation).

And with 'not populated', do you mean no value at all (which would be strange), or a 0.0?

from abb.

Yes I've tried this line and it shows 0.0. I've tried replacing 29 up to 33 and all it shows is 0.0, even when I'm sending data in velocity on the ROS side.

from abb.

Those indices are for the entries in the joint_data array that are unused in the abb_driver:

Skip bytes 29-44. UNUSED. Reserved for Joints 7-10

They are set to 0.0 by the ROS side, so I'm not surprised that you get 0.0 after deserialisation.

As to why the 'last' velocity field is 0.0: that is set by the ROS side as well, as the abb_driver uses the duration field. See abb_driver/src/abb_joint_downloader_node.cpp, lines 68 to 73 and abb_driver/rapid/ROS_motion.mod, line 65.

from abb.

I see, so I'll have to modify code on both sides to be able to send velocity. Thanks!

from abb.

I see, so I'll have to modify code on both sides to be able to send velocity

No, just the ROS side, and specifically those lines that I linked you to. The RAPID code already deserialises the field, but it's just set to 0.0 right now.

Note btw that the duration field is essentially somewhat of the inverse of velocity field, and also that velocity is not a joint velocity in rad/s or deg/s, but is supposed to be a ratio encoding the max velocity for the controller to attain over the associated traj segment (see also Message Structures of the ROS-Industrial Simple Message Protocol - Message Definitions - JOINT_TRAJ_PT).

from abb.

As I have the impression that your question has been answered, I'm going to close this issue.

If you feel that is not correct, feel free to re-open it.

from abb.