12/11/2020 · $ rostopic echo –filter m.data==’foo’ /topic_name. The Python expression can use any Python builtins plus the variable m (the message). For example, to filter based on the frame_id of the first transform in a tf/tfMessage: $ rostopic echo –filter m.transforms[0].child_frame_id == ‘my_frame’ /tf-c. Clear the screen after each message is published.
10/2/2019 · rostopic echo /tf works, but rosrun tf tf _ echo base_link odom doesn’t. save. cancel. The setup: robot (pc (ubuntu) + wifi AP), laptop (ubuntu + wifi), windows (WSL ubuntu + wifi). Everything works just fine between robot and ubuntu laptop, but following happens with WSL: rosrun tf tf _ echo odom base_link. gives:, tf_echo. Tf echo is the simplest tool to look at the numeric values of a specific transform. Tf echo takes two arguments: the reference frame and the target frame. The output of tf echo is the target frame represented in the reference frame. E.g. to get the transformation from turtle1 to turtle2, type: $ rosrun tf tf_echo turtle1 turtle2, rostopic echo is maybe the command line tool I use the most, it’s really useful and saves a lot of time. Get more info about the topic (rostopic info) So, you have found the topic on the list, and you can approximately guess what kind of data is published by printing the data on the terminal.
Using rostopic echo. rostopic echo shows the data published on a topic. Usage: rostopic echo [topic] Let’s look at the command velocity data published by the turtle_teleop_key node. For ROS Hydro and later, this data is published on the /turtle1/cmd_vel topic. In a new terminal, run: $ rostopic echo .
tf /Debugging tools – ROS Wiki, rostopic – ROS Wiki, rostopic – ROS Wiki, tf – ROS Wiki, rostopic echo / tf _static. Here is the output: That’s it for static transforms. Note that in practice, you won’t write the code we wrote above. You will instead use the tf2_ros package. The launch file at the bottom of this page is what you would use.
rostopic echo / tf _static rostopic echo / tf The robot will now be visible as defined in the RVIZ viewer. This an opportunity to verify it looks somewhat as expected. It is also possible to change the Fixed Frame using a drop down menu that RVIZ populated based on transformations for links published on / tf _static .
OpenCV, Urbi, Player Project, Microsoft Robotics Develope…
