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tf tree empty on PR2

Hi all,

We have a PR2 and when starting it up (claim and start) under any account, the tf tree

rostopic echo /tf

No frames show up, only

 --- transforms: []

tf_static is empty,

rosrun tf view_frames

or

rosrun tf2_tools view_frames.py

Do not show any frames. TF is running however, and I can publish new transforms, which will be shown, e.g.

rosrun tf static_transform_publisher 1 0 0 0 0 0 1 link1_parent link1 100

Normally (before and also in simulation) multiple frames should be advertised when starting the PR2. Any hint in what went wrong? Does it have to do with tf2? And where to start looking?

system:

Asked by NickVT on 2014-11-17 06:05:52 UTC

Comments

Your "TF is running" assessment unfortunately says not much. TF is distributed, i.e. TF in itself is not running, Only nodes that provide TF can run and your static_transform_publisher does exactly that. So basic ROS comms work.

Asked by dornhege on 2014-11-17 06:51:37 UTC

If there is not TF on the robot usually something is wrong, which should be indicated by errors. Are there any during start-up? Check if the URDF was loaded on the param server (usually /robot_description) and that a robot_state_publisher is running. There should also be a topic: /joint_states

Asked by dornhege on 2014-11-17 06:53:37 UTC

Answers