Revision history [back]

EDIT: Aug 14 '17

For me, the move_base action server didn't start because I wasn't providing it with a map, as it used a static map for its global costmap. If you aren't using gmapping, or don't plan on using AMCL, the best way to get going is to simply use a rolling window global costmap. This will be very similar to your local costmap, but perhaps use a larger resolution and larger size. You should then be able to use move_base without issue, as it will build the maps itself, rather than looking for an external one.

It only makes sense to use a static global costmap if you are usually going to be working in the same area, as opposed to using your robot in a different location every time. In this case, you should spend some time using gmapping to populate a map with obstacles, which can then be used as a static costmap. The gmapping node uses a laser to create a map in real-time, where each cell is either occupied, free, or unknown. The gmapping node can then share this map to move_base, which can inflate obstacles etc, and use it as the static global costmap. By default, gmapping publishes to /map, and move_base listens to /map. After using gmapping to map your area, use rosrun map_server map_saver map:=/map to save the map as a local YAML file and corresponding image.

The next time you come to navigate in the same area, turn off gmapping and use an instance of map_server to load the previously saved map. This way, the move_base node has access to the previously created map, and can efficiently plan a long distance path. If you want, you can also use AMCL to localize within the same map and provide the odom -> map transform which gmapping was providing, but this isn't related to any issue with the move_base server not loading.

So in summary, if your server isn't loading, check that there is something publishing to the /map topic if using a static costmap.