| ROS Resources: Documentation | Support | Discussion Forum | Index | Service Status | ros @ Robotics Stack Exchange |
Hi All!
I want to save data with "rostopic echo -p > filname" like shown here:
link text
Is it possible to start echo recording with my launch file and how? Is there any other way to record and import data to matlab in a convenient way? Thx for help!!!
Bye
One solution would be to wrap this call into a python node for instance system.exec and the subprocess module (on python.org). This node can then be started by a roslaunch file.
However, I would highly recommend that you use rosbag instead, this is a much more reliable tool that rostopic. For instance you can do:
<launch>
<node pkg="rosbag" type="rosbag" name="rosbag_record"
args="record -o /tmp/slam-map /wide/left/image_raw /wide/left/camera_info /wide/right/image_raw /wide/right/camera_info /rosout"/>
</launch>
Here you will have in /tmp a rosbag file beginning with slam-map followed by the current date and time.
It is then quite straightforward to convert a file to a csv file which can then be read by matlab or whatever 3rd party tool you use. See the rosbag API to know how to do so. I also have written a converter rosbag to csv, it is not in a public repository but if you are interested I can post it here.
Thanks Thomas for your post, it helped me too, but there is one more thing i still would like to understand, in the question rascal asked for running a rostopic echo from a launch, you answered that.
But notice in the question example rascal used a filename output specification (for directory and file name), for example i can use:
$rostopic echo /fix>/home/user/directory/filename.txt
and it will write the messages in the specified directory, is there any way I can run the rostopic echo from a launch like the one you gave, but specifing also the output file directory? Personally I would like to output addicional messages with output="screen" and output topic messages in the .txt file specified in the directory but im not able to find the way to output the file in a specified directory
Thank you very much,
Pablo Payno
Asked: 2012-04-29 02:37:24 -0500
Seen: 1,624 times
Last updated: Dec 01 '13
ROS Answers is licensed under Creative Commons Attribution 3.0 Content on this site is licensed under a Creative Commons Attribution Share Alike 3.0 license.
