| ROS Resources: Documentation | Support | Discussion Forum | Index | Service Status | ros @ Robotics Stack Exchange |
Hello everyone, I'm trying to use the global localisation facilities of AMCL node (calling global_localization service), but every time I try to invoke it, AMCL stop working (publishing the corresponding transformation) and the CPU usage of the process jump up to 99~100%
Also, a similar problems occurs some times when AMCL is not well localised.
Any idea why?
I know how AMCL should work.
After looking at the code I realised that the current AMCL implementation, get stuck while sampling uniformly from the free space in the map for global localisation (it generated more than a million invalid samples before I killed it). A quick fix I did was to look for free space in the map, store the corresponding indices in an array, and sample from the index array uniformly.
This is because AMCL is a particle filter; in order to localize globally, it needs many, many particles, which means much, much computation. Similarly, when AMCL is not well localized, it will generate more particles per step, and therefore require more computation.
The 'A' in AMCL (for "adaptive") refers to the algorithm's ability to choose the particle count automatically, for exactly this reason.
Asked: 2011-08-02 03:15:57 -0500
Seen: 3,650 times
Last updated: Aug 02 '11
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.
