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global_planner finds a path but is not able to find a valid trajectory

asked 2014-01-22 03:38:52 -0500

updated 2014-01-22 23:54:38 -0500

Hi, I am trying to use the global planner global_planner.

It finds a path either in dijsktra or A* and changing the different parameters as this image shows

sweet global path

But then the robot stays still and (most of the times) I get this warning:

[ WARN] [1390404456.350870633, 3038.563000000]: Invalid Trajectory 0.000000, 0.000000, -0.300000, cost: -1.000000

until a fatal error appears, after 6 seconds:

[ERROR] [1390404456.403586383, 3038.611000000]: Aborting because a valid control could not be found. Even after executing all recovery behaviors
  • Is there some parameter or remap missing in the global_planner wiki?
  • Is there any example of the global_planner with a launch and yaml files?

Thanks in advance!

Update

I found out that the global_plan publishes the poses from goal to origin whereas navfn publishes them from origin to goal. I would say this is the problem that makes the robot stay still, I copy a couple of results:

oringin (x≅0) and goal (x≅1) of a path in navfn:

  pose: 
    position: 
      x: -0.1
      y: -0.05
...
  pose: 
    position: 
      x: 0.998614728451
      y: 0.0215734690428

oringin (x≅0) and goal (x≅1) of a path in global_planner:

  pose: 
    position: 
      x: 1.0
      y: 0.0
...
  pose: 
    position: 
      x: -0.25
      y: -0.05
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2 Answers

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answered 2014-01-23 02:31:11 -0500

updated 2014-01-23 02:45:42 -0500

I'm pushing a patch but I've just made it work reversing the vector of the plan.

https://github.com/ros-planning/navigation/blob/hydro-devel/global_planner/src/planner_core.cpp#L329

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answered 2014-01-22 10:26:01 -0500

David Lu gravatar image

Given your error message, there is no remap problem with global planner. I'm guessing its a local planner issue.

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Comments

I found out that problem described in the update of the question, I've sent a patch to solve it. It works to me, but maybe there's a better approach. Thanks anyway for your answer it really helped me to find out what was happening!

martimorta gravatar image martimorta  ( 2014-01-23 02:49:00 -0500 )edit

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Asked: 2014-01-22 03:38:52 -0500

Seen: 1,099 times

Last updated: Jan 23 '14