Gmapping launch error [closed]

edit

Hi everyone,

I am new to ROS and have been learning from the book "Mastering ROS for Robotics Programming". I have run into an issue in Chapter 4 where a simulated diff wheeled robot uses gmapping to build a map of Willow Garage world. I am using ROS Indigo on a dual boot machine running Windows 10 and Ubuntu 14.04 on separate HDDs.

For this gmapping simulation, the robot model is first launched in Gazebo in Willow Garage world. Then gmapping is launched from the same package. Next keyboard teleop is launched from a separate package, and finally the robot is visualized in RViz.

When I run:

roslaunch diff_wheeled_robot_gazebo diff_wheeled_gazebo_full.launch

The robot launches in Gazebo in an empty world instead of Willow Garage and the terminal displays the following warnings:

[ WARN] [1502832331.629880560]: The 'state_publisher' executable is deprecated. Please use 'robot_state_publisher' instead [ WARN] [1502832331.632663525]: The root link base_footprint has an inertia specified in the URDF, but KDL does not support a root link with an inertia. As a workaround, you can add an extra dummy link to your URDF.

Next, when I run:

roslaunch diff_wheeled_robot_gazebo gmapping.launch

The terminal displays some output including the following errors:

[ WARN] [1502833436.250359091, 1084.378000000]: Timed out waiting for transform from base_footprint to map to become available before running costmap, tf error: . canTransform returned after 1084.38 timeout was 0.1.
[ WARN] [1502833441.391352686, 1089.464000000]: Timed out waiting for transform from base_footprint to map to become available before running costmap, tf error: Could not find a connection between 'map' and 'base_footprint' because they are not part of the same tree.Tf has two or more unconnected trees.. canTransform returned after 0.103 timeout was 0.1.
[ WARN] [1502833446.596302597, 1094.560000000]: Timed out waiting for transform from base_footprint to map to become available before running costmap, tf error: Could not find a connection between 'map' and 'base_footprint' because they are not part of the same tree.Tf has two or more unconnected trees.. canTransform returned after 0.104 timeout was 0.1.
[ WARN] [1502833451.529031298, 1099.367000000]: MessageFilter [target=odom ]: Dropped 100.00% of messages so far. Please turn the [ros.gmapping.message_notifier] rosconsole logger to DEBUG for more information.

The packages and associated files can be accessed at https://github.com/qboticslabs/mastering_ros. As far as I know, they should work, but something seems to be amiss. I also updated the navigation package to make sure nothing is missing from it. Has anybody had a similar issue with a gmapping simulation? How do I fix this?