# Revision history [back]

### robot_localization asking for map to odom transform

So I just recently migrated from robot_pose_ekf to robot_localization as I heard it's better. I'm fusing data from wheel odometry, imu and laser_scan_matcher as odom0, imu0 and pose0 respectively. I followed the instructions in configuring the parameters and set the frames as such:
map_frame: map
odom_frame: odom
base_link_frame: base_link
world_frame: map

The documentation tells me this should make the ekf_localization node publish the transform from map to odom if the publish_tf param is set to true. Sure, it does, but I also keep getting this warning:
[ WARN] [1521163510.296212370]: Transform from odom to map was unavailable for the time requested. Using latest instead.
And once in a while this warning: [ WARN] [1521163517.010447912]: Failed to meet update rate! Took 0.035404531000000002972 seconds. Try decreasing the rate, limiting sensor output frequency, or limiting the number of sensors.

Why would it be looking up the transform of what it's supposed to be broadcasting instead? It's still doing its job, but I'm just concerned somewhere it ignores some data because of this warning and curious why the warning comes up in the first place. Thanks in advance for any insight on the matter!

### robot_localization asking for map to odom transform

So I just recently migrated from robot_pose_ekf to robot_localization as I heard it's better. I'm fusing data from wheel odometry, imu and laser_scan_matcher as odom0, imu0 and pose0 respectively. I followed the instructions in configuring the parameters and set the frames as such:
map_frame: map
odom_frame: odom
base_link_frame: base_link
world_frame: map

The documentation tells me this should make the ekf_localization node publish the transform from map to odom if the publish_tf param is set to true. Sure, it does, but I also keep getting this warning:
[ WARN] [1521163510.296212370]: Transform from odom to map was unavailable for the time requested. Using latest instead.
And once in a while this warning: [ WARN] [1521163517.010447912]: Failed to meet update rate! Took 0.035404531000000002972 seconds. Try decreasing the rate, limiting sensor output frequency, or limiting the number of sensors.

Why would it be looking up the transform of what it's supposed to be broadcasting instead? It's still doing its job, but I'm just concerned somewhere it ignores some data because of this warning and curious why the warning comes up in the first place. Thanks in advance for any insight on the matter!

Here's my TF tree:

 3 None jayess 5039 ●17 ●55 ●69

### robot_localization asking for map to odom transform

So I just recently migrated from robot_pose_ekf to robot_localization as I heard it's better. I'm fusing data from wheel odometry, imu and laser_scan_matcher as odom0, imu0 and pose0 respectively. I followed the instructions in configuring the parameters and set the frames as such:

map_frame: mapmap
odom_frame: odom
world_frame: map
  odom_frame: odom  base_link_frame: base_link  world_frame: map

The documentation tells me this should make the ekf_localization node publish the transform from map to odom if the publish_tf param is set to true. Sure, it does, but I also keep getting this warning:

[ WARN] [1521163510.296212370]: Transform from odom to map was unavailable for the time requested. Using latest instead.instead.
  

And once in a while this warning:

[ WARN] [1521163517.010447912]: Failed to meet update rate! Took 0.035404531000000002972 seconds. Try decreasing the rate, limiting sensor output frequency, or limiting the number of sensors.sensors.
 

Why would it be looking up the transform of what it's supposed to be broadcasting instead? It's still doing its job, but I'm just concerned somewhere it ignores some data because of this warning and curious why the warning comes up in the first place. Thanks in advance for any insight on the matter!

Here's my TF tree: