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View Full Version : N00b questions about ROS time



DaveC
04-02-2012, 03:35 PM
When ROS is passing time stamps around, it looks like it is seconds in floating point. So what are the seconds? Is that the standard UNIX interpretation, ie: seconds-since-the-epoch? When ROS nodes running on different systems are trying to synchronize, do they all use their own wall-clocks to time-stamp the generated sensor readings, etc?

-dave

lnxfergy
04-02-2012, 04:33 PM
The time is in UNIX standard seconds-since-the-epoch (january 1, 1970). If you have multiple different computers, you want to make their clocks synchronized (NTP via chrony works well on Ubuntu).

-Fergs

DaveC
04-02-2012, 05:41 PM
Thanks, makes sense. I can see where NTP is going to be required to make the time stamps work well.