nav_msgs/OccupancyGrid topic doesn't exist
Hi, I have set up a simple subsriber like the one in this tutorial and am trying to use it to get data from the nav_msgs/OccupancyGrid topic. As the doc specifies, this data is in the form of an Int8 [] so the only difference between the tutorial and my code is I replaced "String" with "Int8MultiArray"
I am running what I think is a fairly standard hector_mapping setup, and then I try and launch my subscriber node. The node launches fine and sits there forever, never receiving any messages. When I try rostopic list the topic is not there, despite the fact that the documentation for hector_mapping says that it publishes to this nav_msgs/OccupancyGrid topic.
It seems like I'm missing something to tell hector_mapping to publish, except that using rosrun map_server map_saver works perfectly, so clearly the data is there. What am I doing wrong?
