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skasperski / navigation_2d

ROS nodes to navigate a mobile robot in a planar environment
GNU General Public License v3.0
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Understanding tf used in nav2d in real vs simulated robot #60

Closed aditi741997 closed 3 years ago

aditi741997 commented 3 years ago

Hello,

I have been looking at the tf into more details [while running nav2d with gazebo and turtlebot3], and in nav2d module, it seems that : TF between odom and base_footprint [which is the robot base frame] is published by gazebo, and used by the Local COstmap [in operator], by Operator node, by Mapper's Scan callback and by the Navigator node.

TF between map and odom is published by the mapper, and is used by navigator.

I had two questions :

  1. Is my understanding of who is publishing & subscribing to TF correct?
  2. If yes, then, in a real robot, where would the odom - base_footprint transform come from? [which is currently being published by the simulator]
aditi741997 commented 3 years ago

I realized that the odom - base_frame transform is actually published by the odometry source itself. http://wiki.ros.org/navigation/Tutorials/RobotSetup/Odom