Ask Your Question
1

strange dates in ROS' bags

asked 2012-11-27 05:08:44 -0500

ubisum gravatar image

updated 2012-11-27 07:17:02 -0500

Eric Perko gravatar image

hello everyone. I'm trying to record the messages published to two topics inside a bag. The creation of .bag file is created correctly, but when I write

rosbag info subset.bag

this is what I get:

path:        subset.bag
version:     2.0
duration:    3:45s (225s)
start:       Jan 01 1970 01:36:56.10 (2216.10)
end:         Jan 01 1970 01:40:41.30 (2441.30)
size:        20.5 MB
messages:    4507
compression: none [28/28 chunks]
types:       nav_msgs/Odometry     [cd5e73d190d741a2f92e81eda573aca7]
             sensor_msgs/LaserScan [90c7ef2dc6895d81024acba2ac42f369]
topics:      /base_scan   2254 msgs    : sensor_msgs/LaserScan
             /odom        2253 msgs    : nav_msgs/Odometry

How is it possible that ROS saves messages as I had sent them in 1970? Thanks for help.

edit retag flag offensive close merge delete

1 Answer

Sort by ยป oldest newest most voted
2

answered 2012-11-27 05:29:15 -0500

dornhege gravatar image

This looks like time offsets to me. I.e. the timestamps written are not absolute, but "time since running" or something like that.

Unix time starts at Jan 01 1970, 00:00.

edit flag offensive delete link more

Comments

how can i modify timestamp of bag already generated? thanks

ubisum gravatar imageubisum ( 2012-12-23 22:18:16 -0500 )edit

Look into rosbag filter.

dornhege gravatar imagedornhege ( 2013-01-08 03:33:04 -0500 )edit

Your Answer

Please start posting anonymously - your entry will be published after you log in or create a new account.

Add Answer

Question Tools

Stats

Asked: 2012-11-27 05:08:44 -0500

Seen: 74 times

Last updated: Nov 27 '12