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1 | initial version |
A time of zero means that time has not been initialized. Time documentation
It will have needed to check the parameter server for use_sim_time and then fallen back to wall clock time. (Or if you're in a simulator to have recieved a /clock signal.)
The reason it's not publishing is a similar problem that you're calling publish before the publisher has estabilized a connection with the subscribers. It's not uncommon for a message published immediately after a publisher is created to not be received.
2 | No.2 Revision |
A time of zero means that time has not been initialized. Time documentation
It will have needed to check the parameter server for use_sim_time and then fallen back to wall clock time. (Or if you're in a simulator to have recieved a /clock signal.)
The reason it's not publishing is a similar problem that you're calling publish before the publisher has estabilized a connection with the subscribers. It's not uncommon for a message published immediately after a publisher is created to not be received.
Edit:
As mentioned in the docs. A common approach is to loop waiting for non-zero time now values. (The duration sleep implicitly does this.)