Re: [ros-users] tf spits a lookup exception

>     tf.LookupException: Frame id /map does not exist! When trying to
> transform between /base_link and /map.

>     ~>rosrun tf tf_monitor base_link map
>     Waiting for transform chain to become available between /base_link and
> /map

>     RESULTS: for /base_link to /map
>     Chain is: /base_link -> /base_footprint -> /odom_combined -> /map
>     Net delay     avg = 0.00684423: max = 0.054

>     Frames:
>     Frame: /base_footprint published by /robot_pose_ekf Average Delay:
> 0.0185 Max Delay: 0.026
>     Frame: /base_link published by /robot_state_publisher Average Delay:
> 0.0075 Max Delay: 0.008
>     Frame: /odom_combined published by /slam_gmapping Average Delay: 0 Max
> Delay: 0

>     All Broadcasters:
>     Node: /robot_pose_ekf 33.5196 Hz, Average Delay: 0.0185 Max Delay:
> 0.026
>     Node: /robot_state_publisher 55.5556 Hz, Average Delay: 0.0075 Max
> Delay: 0.008
>     Node: /slam_gmapping 25 Hz, Average Delay: 0 Max Delay: 0