/tf from /base_link to /camera_link

Question

Hi,

I'm using ccny_rgbd_tools which gives me a transform between /camera_link, which is the base_frame, and /odom, which is the fixed_frame.

I'm using MoveIt!, where I have a urdf model which as a camera_link and a base_link, which supposedly already gives a static_tf between them. I have a virtual_joint between camera_link and odom (which is floating, cause it is from a quadrotor).

Now running demo.launch (without the static_transform_publisher between camera_link and odom) I get this on the command line:

[ WARN] [1404846265.951041568]: No transform available between frame 'odom' and planning frame '/base_link' (Could not find a connection between 'base_link' and 'odom' because they are not part of the same tree.Tf has two or more unconnected trees.)

I have a /tf between odom and camera_link, and a /tf from base_link to camera_link, which builds up a tree. Why does it needs a /tf between base_link and odom?

Thanks in advance!

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Originally posted by TSC on ROS Answers with karma: 210 on 2014-07-08

Post score: 0

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Original comments

Comment by sai on 2014-07-08:
can you try 'rosrun tf view_frames' and 'evince frames.pdf' and look or show the TF tree..this might give an idea of what exactly is happening down there.

Comment by TSC on 2014-07-09:
Already did that! Odom doesn't even appear!

Comment by sai on 2014-07-09:
So is your ccny package running appropriately ? can you get the pose from 'rostopic echo \vo' and actually see the estimated pose in real time.

Answer 1

ccny pkg is working properly. But now its working on Rviz also.

What I did was use robot_pose_ekf that receives the data from /vo and does the tf to base_footprint. Added a static_transform between the base_footprint and base_link and now I have the URDF position being updated in Rviz.

It kinda lags and sometimes has some jumps. Will probably have to add the IMU info also. Anyway, I would like to try the hector_localization package also to fuse other sensors, but I'm facing some difficulties due to to lack of documentation!

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Originally posted by TSC with karma: 210 on 2014-07-09

This answer was ACCEPTED on the original site

Post score: 0