Tf has two or more unconnected trees
Hey! I was trying to use a Kinect fusion package for my project on Robot Workcell Discovery. I am using ROS Kinetic and Ubuntu 16.04.
While launching the Kinect fusion node, I face the following error.
terminate called after throwing an instance of 'tf2::LookupException'. what(): Could not find a connection between 'volume_pose' and 'camera_depth_optical_frame' because they are not part of the same tree. Tf has two or more unconnected trees.
How as per the Link to the tf frames.pdf file generated created using rosrun tf view_frames these two frames seem to be in the same tree.
On some occasions, the same launch file gives the following error.
terminate called after throwing an instance of 'tf2::LookupException'
what(): "volume_pose" passed to lookupTransform argument target_frame does not exist.
This is the related code
if (!camera->nodeHandle.getParam("use_pose_hints", use_pose_hints_))
{
ROS_INFO("Failed to get use_pose_hints flag!");
}
ROS_INFO_STREAM("Use pose hints set to " << use_pose_hints_);
tfListener_.waitForTransform("volume_pose", "camera_depth_optical_frame", ros::Time::now(), ros::Duration(2));
tfListener_.lookupTransform("volume_pose", "camera_depth_optical_frame", ros::Time(0), previous_volume_to_sensor_transform_);
}
}
I have added Listener. waitForTransform() as mentioned in this answer. I have also added <param name="/use_sim_time" value="true"/> on the top of my launch files as as mentioned by some other answers, however the problem still persists.
There definitely seems to be a problem of the volume_pose not being available in time. What could be the potential reason and solution for this issue?
Edit: In one case, I received this error message as well which according to this link is again due to a delayed source of frames.
Warning: TF_OLD_DATA ignoring data from the past for frame table at time 0.165 according to authority unknown_publisher
Output of tf monitor
Waiting for transform chain to become available between volume_pose and camera_depth_optical_frame
RESULTS: for volume_pose to camera_depth_optical_frame
Chain is: volume_pose -> base_link -> table -> world -> shoulder_link -> upper_arm_link -> forearm_link -> wrist_1_link -> wrist_2_link -> wrist_3_link -> tool0 -> camera_link -> camera_depth_frame -> camera_depth_optical_frame
Net delay avg = 0.00997896: max = 0.099
Frames:
Frame: base_link published by unknown_publisher(static) Average Delay: 0 Max Delay: 0
Frame: camera_depth_frame published by unknown_publisher(static) Average Delay: 0 Max Delay: 0
Frame: camera_depth_optical_frame published by unknown_publisher(static) Average Delay: 0 Max Delay: 0
Frame: camera_link published by unknown_publisher(static) Average Delay: 0 Max Delay: 0
Frame: forearm_link published by unknown_publisher Average Delay: 0.000272727 Max Delay: 0.003
Frame: shoulder_link published by unknown_publisher Average Delay: 0.000272727 Max Delay: 0.003
Frame: table published by unknown_publisher Average Delay: -0.0666667 Max Delay: 0
Frame: tool0 published by unknown_publisher(static) Average Delay: 0 Max Delay: 0
Frame: upper_arm_link published by unknown_publisher Average Delay: 0.000272727 Max Delay: 0.003
Frame: volume_pose published by unknown_publisher Average Delay: 0 Max Delay: 0
Frame: wrist_1_link published by unknown_publisher Average Delay: 0.000272727 Max Delay: 0.003
Frame: wrist_2_link published by unknown_publisher Average Delay: 0.000272727 Max Delay: 0.003
Frame: wrist_3_link published by unknown_publisher Average Delay: 0.000272727 Max Delay: 0.003
All Broadcasters:
Node: unknown_publisher 85 Hz, Average Delay: -0.0233529 Max Delay: 0.003
Node: unknown_publisher ...
