No transform from [robot_1/base_link] to [/map]
I want to use 'Gmapping' with multiple robots. I checked the 'robot_1/scan' value with the actual robot, and designated namespace to distinguish the robots. However, rviz generates warnings such as 'No transform from [robot_1/base_link] to frame [map]' and does not display the laser and map. What's the problem?
Clearly, you can see there are two trees in your first screenshot. Moreover, you may notice that
robot_1/base_link
andmap
are in two different trees. This is why there is no such transformation available.