got TF_OLD_DATA warning from time to time

[lianghongzhuo]

Summary

Introduction to the issue I got TF_OLD_DATA from time to time, only restart the robot launch file can solve it. error msg is like:

[ WARN] [1624001595.379673101]: TF_OLD_DATA ignoring data from the past for frame arm_upper_arm_link at time 1.624e+09 according to authority /robot_state_publisher
Possible reasons are listed at http://wiki.ros.org/tf/Errors%20explained
[ WARN] [1624001595.379702295]: TF_OLD_DATA ignoring data from the past for frame arm_shoulder_link at time 1.624e+09 according to authority /robot_state_publisher
Possible reasons are listed at http://wiki.ros.org/tf/Errors%20explained
[ WARN] [1624001595.379725272]: TF_OLD_DATA ignoring data from the past for frame arm_wrist_1_link at time 1.624e+09 according to authority /robot_state_publisher
Possible reasons are listed at http://wiki.ros.org/tf/Errors%20explained
[ WARN] [1624001595.379750800]: TF_OLD_DATA ignoring data from the past for frame arm_wrist_2_link at time 1.624e+09 according to authority /robot_state_publisher
Possible reasons are listed at http://wiki.ros.org/tf/Errors%20explained
[ WARN] [1624001595.379775379]: TF_OLD_DATA ignoring data from the past for frame arm_wrist_3_link at time 1.624e+09 according to authority /robot_state_publisher
Possible reasons are listed at http://wiki.ros.org/tf/Errors%20explained
[ WARN] [1624001595.380370301]: TF_OLD_DATA ignoring data from the past for frame arm_forearm_link at time 1.624e+09 according to authority /robot_state_publisher
Possible reasons are listed at http://wiki.ros.org/tf/Errors%20explained
[ WARN] [1624001595.380401027]: TF_OLD_DATA ignoring data from the past for frame arm_upper_arm_link at time 1.624e+09 according to authority /robot_state_publisher
Possible reasons are listed at http://wiki.ros.org/tf/Errors%20explained
[ WARN] [1624001595.380426203]: TF_OLD_DATA ignoring data from the past for frame arm_shoulder_link at time 1.624e+09 according to authority /robot_state_publisher
Possible reasons are listed at http://wiki.ros.org/tf/Errors%20explained
[ WARN] [1624001595.380452244]: TF_OLD_DATA ignoring data from the past for frame arm_wrist_1_link at time 1.624e+09 according to authority /robot_state_publisher
Possible reasons are listed at http://wiki.ros.org/tf/Errors%20explained
[ WARN] [1624001595.380478272]: TF_OLD_DATA ignoring data from the past for frame arm_wrist_2_link at time 1.624e+09 according to authority /robot_state_publisher
Possible reasons are listed at http://wiki.ros.org/tf/Errors%20explained
[ WARN] [1624001595.380502892]: TF_OLD_DATA ignoring data from the past for frame arm_wrist_3_link at time 1.624e+09 according to authority /robot_state_publisher
Possible reasons are listed at http://wiki.ros.org/tf/Errors%20explained
[ WARN] [1624001595.380555666]: TF_OLD_DATA ignoring data from the past for frame arm_forearm_link at time 1.624e+09 according to authority /robot_state_publisher
Possible reasons are listed at http://wiki.ros.org/tf/Errors%20explained
[ WARN] [1624001595.380582803]: TF_OLD_DATA ignoring data from the past for frame arm_upper_arm_link at time 1.624e+09 according to authority /robot_state_publisher
Possible reasons are listed at http://wiki.ros.org/tf/Errors%20explained
[ WARN] [1624001595.380611405]: TF_OLD_DATA ignoring data from the past for frame arm_shoulder_link at time 1.624e+09 according to authority /robot_state_publisher
Possible reasons are listed at http://wiki.ros.org/tf/Errors%20explained

My understanding is that the timestamp that publishes the joint state of the ur robot is late than the current timestamp of tf has.

Versions

• ROS Driver version: master
• Affected Robot Software Version(s): master
• Affected Robot Hardware Version(s): UR10e
• Robot Serial Number:
• UR+ product(s) installed: UR10e
• URCaps Software version(s):

Impact

No impact everything is working except the warning.

Use Case and Setup

ur driver is on master, ur client is from Debian.

Project status at point of discovered

When did you first observe the issue?

• The issue comes not so often, several times per day.

Steps to Reproduce

It's hard to reproduce, I guess there is some network communication drop?

Expected Behavior

No warning, or have warning sometimes, but recover soon. In my case, once the warning happens, it won't disappear unless I restart the robot launch file.

Workaround Suggestion

restart the robot launch file

[fmauch]

This should not happen, but I also cannot imagine how this should happen.

Do you run a multi-machine ROS setup? If there are multiple machines part of one ROS network, there could be issues, if their times are not synchronized exactly. But I would expect a different output in that case.

[lianghongzhuo]

Thanks for the reply. There is only one ros machine.