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Why is A* used as global planner in move_base ?

asked 2019-09-11 10:52:09 -0600

robot_new_user gravatar image

Can someone shed some light on why A* star is used for global planner in move_base. I can see that there is an option to use Djikstra's algorithm as well. What are the main benefits of A* as opposed to using RRT or RRT*?

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There is a Stackoverflow post about A* here take a look at that, mybe this gives a bit of an insight, also here you can find a comparison between Dijkstra and RRT.

LeoE gravatar image LeoE  ( 2019-09-11 11:11:11 -0600 )edit

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answered 2019-09-11 16:05:49 -0600

David Lu gravatar image
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answered 2019-09-11 15:07:55 -0600

This is a good basic reference for A* vs Dijkstra. A* has an added heuristic trying to expand the potential field in the direction of the goal. Its not necessarily promised to be faster, but in most cases it is.

http://theory.stanford.edu/~amitp/Gam...

RRT and RRT-variants are sampling based and not search based. They will require smoothing after the search. In practice RRTs are nice for higher dimensional spaces like manipulators, but in lower dimensional space (like 2D mobile robots) its not really adventitious over search based. WIth that said, there are RRT implemented global planner plugins if you google for it for you to try out youself if you like.

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Asked: 2019-09-11 10:52:09 -0600

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Last updated: Sep 11 '19