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Launch modes of BLORT

Description: This tutorial explains the launch modes of BLORT and what they mean.

Tutorial Level: INTERMEDIATE


Running a Tracker-Detector system all the time can be too expensive in computation time.

If you are certain when you would like to use it, it would be a straightforward idea to launch everything at that time but this option is also a bit complicated. What we have implemented instead in blort_ros is that you have two different ways to launch BLORT.

We named these launch modes. You can set the launch_mode for BLORT by passing a parameter through the ROS Parameter Server. If you take a look at the launch files in the blort_ros package, you can notice the following lines:

<param name="launch_mode" value="tracking" />


<param name="launch_mode" value="singleshot" />

This is how you can control the launch mode. See the below figures about their working mechanism.


Tracking mode: It's the usual mode that you have seen so far in the Tutorials. It will immediately start BLORT with the Detector as usual.

Singleshot mode: In this mode there is a service advertised and calling it will run BLORT for a given amount of time and return a pose result if any. This way you don't have to worry about the computation cost of constant tracking.

Wiki: blort_ros/Tutorials/LaunchModes (last edited 2012-07-04 10:02:05 by BenceMagyar)