ROS Resources: Documentation | Support | Discussion Forum | Index | Service Status | ros @ Robotics Stack Exchange
Ask Your Question
1

Universal robots calibration offsets

asked 2014-01-22 02:28:19 -0500

davinci gravatar image

updated 2014-01-22 02:40:42 -0500

gvdhoorn gravatar image

When running the Universal robots ur5_driver and connecting to the robot I always see these messages:

[WARN] [WallTime: 1390394126.210844] No calibration offset for joint "shoulder_pan_joint"
[WARN] [WallTime: 1390394126.212435] No calibration offset for joint "shoulder_lift_joint"
[WARN] [WallTime: 1390394126.214354] No calibration offset for joint "elbow_joint"
[WARN] [WallTime: 1390394126.216533] No calibration offset for joint "wrist_1_joint"
[WARN] [WallTime: 1390394126.219127] No calibration offset for joint "wrist_2_joint"
[WARN] [WallTime: 1390394126.222308] No calibration offset for joint "wrist_3_joint"
[ERROR] [WallTime: 1390394126.223789] Loaded calibration offsets: {}

I can however not find anything in the documentation about this. Is this to compensate any drift? Or with the calibration loaded you don't have to initialize the joints by moving them around? How can this be used?

edit retag flag offensive close merge delete

Comments

Can you please verify which version of the driver you are using? Debian (ROS version) or from source (which branch)?

sedwards gravatar image sedwards  ( 2014-01-22 04:51:47 -0500 )edit

I think it is the Debian version (as I copied it from /opt/ros/fuerte) of this package: http://wiki.ros.org/ur5_driver

davinci gravatar image davinci  ( 2014-01-22 20:54:58 -0500 )edit

Did this end up being an issue for you? I'm having the exact same [WARN] message.

maxgitt gravatar image maxgitt  ( 2017-08-03 16:43:10 -0500 )edit

when these warns occured,the python file didn't run successfully to control the robot.As the answer said,the robot should run well in this situation.Is there something else wrong with my robot?

expo gravatar image expo  ( 2018-10-19 03:51:53 -0500 )edit

2 Answers

Sort by ยป oldest newest most voted
1

answered 2014-01-23 04:11:39 -0500

This isn't a real answer, but I can tell you that we work without the joint offsets all the time. The calibration procedure of the UR is separate from any ROS piece. In my opinion, the calibration done by the UR is good enough and no further offsets are required. The offsets are really only needed if the mechanics of the UR do not properly locate the true "zero" position. Most industrial arms have well calibrated zero position since they often depend on accurate kinematics for cartesian control.

edit flag offensive delete link more

Comments

As you said,the robot should run well in this situation.but when these warns occured,the python file didn't run successfully to control my robot.So sad

expo gravatar image expo  ( 2018-10-19 03:53:05 -0500 )edit
0

answered 2018-10-19 06:08:05 -0500

expo gravatar image

Actually,we have solve the problem by degrad the debian to 2016.this problem may be caused by the debian versian.Also,there may be some other wrong,for as the debian version is 2016 yet,today the problem occured again.

edit flag offensive delete link more

Question Tools

1 follower

Stats

Asked: 2014-01-22 02:28:19 -0500

Seen: 1,751 times

Last updated: Oct 19 '18