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#! /usr/bin/env python
import rospy
rospy.init_node('h')
print(rospy.Time.now()) => 0
Prints zero? Here is the context
rosparam get /use_sim_time -> true
$ rostopic info /clock Type: rosgraph_msgs/Clock
Publishers:
Subscribers:
I know you've already reinstalled -- but in case someone else (or even you) runs into this later -- it is possible you simply have a race condition. If you put the print() statement in a loop, I imagine your values would start to increase. It is possible that either the python node came up and printed before gazebo really started publishing /clock, or that the print statement happened before the first clock message came in.
I've seen some codebases where the developers explicitly wait until time > 0 before letting the rest of the initialization proceed.
Sad to say, I had to uninstall all of ROS, delete all the state that I could find, and then reinstall. Pretty delicate creature.
If you're using system time and replaying a bagfile you'll need to make sure that /clock has been recorded (otherwise set use_sim_time to false) .
Asked: 2018-08-19 09:10:04 -0500
Seen: 2,648 times
Last updated: Oct 30 '22
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Is Gazebo paused?
No, it’s up. Also when I rostopic echo /clock I see the messages go by. Also when I set /use_sim_time to False the same code works.
Anyone? I am stumped. Thinking that I had corrupted something in my install, i see the same behavior on a different computer altogether.