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ubuntu 12.04 and fuerte
How to use rxplot to plot the transforms? They have the position and orientation.
Example
header: seq: 0 stamp: secs: 1311867210 nsecs: 774027961 frame_id: /world child_frame_id: /kinect transform: translation: x: 0.208460861206 y: -1.06889804077 z: 1.87455181885 rotation: x: -0.0425775370706 y: -0.0287192089576 z: 0.77849649613 w: 0.625544215773
In my opinion, rxplot is not the best tool at plotting tf's. I would recommend you to use rviz for that.
If you want to see x, y and z positions and orientations maybe you should consider using an odometry or pose topic parsed from the node tf or something similar, in order to avoid what Adolfo Rodríguez comments.
There is no "best tool", as the goodness measure depends a lot on your requirements. Rviz excels at visualizing instantaneous frame configurations, but if you're interested in visualizing time series a plotting tool might be more appropriate.
...additionally the details of a specific implementation can make your life easier or harder. Plotting a /tf time series with rxplot/rqt has its difficulties, but plotting a pose_stamped topic is straightforward. YMMV...
The following snippet will print the x coordinate of the first transform in a tf message:
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rxplot /tf/transforms[0]/transform/translation/x
Big caveat: if there are multiple publishers of the /tf topic, this won't work, as the transform vector index (the [0] above) will not always represent the same frame. Further, f you're querying a nonzero index, it might be possible that the index does not even exist in a given message.
I would recommend republishing the transform(s) of interest as a separate pose(stamped) message and plot from there. More overhead, but less surprises.
I ran into same question and what we found so far...
For example, we have transformation between world, earth, moon, and we want to plot time-series data of transform between world and moon
1) Convert world <- moon TF transform to PoseStamped (and others) and plot using rqt_plot
tf_to_pose.py convert arbitrary transform to geometry_msgs/PoseStamped message, which is easy to plot by rqt_plot tool
2) Rebroadcast world <- moon TF transforms with different name, ad world <- moon2, then plot with plotjuggler
plotjuggler capable of plot tf transform ONLY between child frame and parent frame. So if we can rebroadcast tf transforms with different frame id on the fly
3) use rviz plugins
duplicated questions in answers.ros.org suggested few useful links, for example tf_trajectory shows
4) use hector_trajectory_server
duplicated questions in answers.ros.org also suggested to use hector_trajectory_server, you can visualize as Path on rviz, but I personally do not know how to plot on rqt and other tools.
You can find example code at https://gist.github.com/k-okada/8d4f6...
Asked: 2013-03-20 20:06:25 -0500
Seen: 2,659 times
Last updated: Jun 19 '21
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