Extrapolation error using hector_mapping + move_base

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Hello all,

I have a problem with my robot setup which I cannot resolve, even after reading all relevant posts on here. I really would appreciate your help.

Problem Description

The system starts up not generating any errors (see https://dl.dropboxusercontent.com/u/10986309/2013-05-23_ros.answers/start_up_log.txt), producing an accurate map, and localization working well, too. As soon as I select a goal in rviz, move_base reproducibly throws the following errors:

[  ...]
[ERROR] [1369321339.784772926]: Extrapolation Error: Unable to lookup transform, cache is empty, when looking up transform from frame [/odom] to frame [/map]
[ERROR] [1369321339.785409391]: Global Frame: /odom Plan Frame size 107: /map
[ WARN] [1369321339.785726634]: Could not transform the global plan to the frame of the controller
[ERROR] [1369321340.434425166]: Extrapolation Error: Unable to lookup transform, cache is empty, when looking up transform from frame [/odom] to frame [/map]
[ERROR] [1369321340.434493357]: Global Frame: /odom Plan Frame size 107: /map
[ WARN] [1369321340.434528719]: Could not transform the global plan to the frame of the controller
[  ...]

However, if I make the following change in the local_costmap_params.yaml file:

local_costmap: global_frame: /odom

to

local_costmap: global_frame: /map

I don't get any errors and move_base generates a plan to the goal, which is also displayed in rviz. Unfortunately, the generated cmd_vel commands are very shaky, oscillate and weird navigation behaviour is the result.

My Setup

• Robot: Custom robot with chain drive, i.e. non-holonomic. I have written a base_controller node for it which sends drive commands to the motors and uses the encoder information to calculate odometry and publish as tf+nav_msg (as described http:// www.ros.org/wiki/navigation/Tutorials/RobotSetup/Odom). I have also created a *.urdf file and use robot_state_publisher to publish the tf's for the model.
• Sensors: Hokuyo UTM-30LX laser scanner
• Nodes: max_driver (custom base_controller), hector_mapping, move_base, hokuyo_node
• hector_mapping config:

[hector_config.launch] https:// dl.dropboxusercontent.com/u/10986309/2013-05-23_ros.answers/hector_config.launch

• move_base config:

[move_base_config.launch] https:// dl.dropboxusercontent.com/u/10986309/2013-05-23_ros.answers/move_base_config.launch

[base_local_planner_params.yaml] https:// dl.dropboxusercontent.com/u/10986309/2013-05-23_ros.answers/base_local_planner_params.yaml

[costmap_common_params.yaml] https:// dl.dropboxusercontent.com/u/10986309/2013-05-23_ros.answers/costmap_common_params.yaml

[global_costmap_params.yaml] https:// dl.dropboxusercontent.com/u/10986309/2013-05-23_ros.answers/global_costmap_params.yaml

[local_costmap_params.yaml] https://dl.dropboxusercontent.com/u/10986309/2013-05-23_ros.answers/local_costmap_params.yaml

• Remote nodes: The hokuyo_node and the base_controller node run on an embedded PC, which is connected via ethernet to a powerful laptop running the remaining nodes. The time of both machines is synced via crony.
• SW-Version: Ubuntu 12.04 + ROS Groovy, everything up to date

Debug Info

• tf tree: [link] (https:// dl.dropboxusercontent.com/u/10986309/2013-05-23_ros.answers/frames.pdf)
• tf_monitor output:

ros@Base:~$ rosrun tf tf_monitor
RESULTS: for all Frames

Frames:
Frame: /base_frame published by /max_driver Average Delay: -0.00377412 Max Delay: 0
Frame: /base_laser published by /robot_state_publisher Average Delay: -0.476582 Max Delay: 0
Frame: /base_laser_cap published by /robot_state_publisher Average Delay: -0.476592 Max Delay: 0
Frame: /base_laser_mount_box published by /robot_state_publisher Average Delay: -0.476591 Max Delay: 0 ...