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DWB local planner problem when an obstacle is detected on the goal

Dear all,

I am facing a problem that I do not know how to fix it.

I use the movebase/globalplanner as the global_planner and the DWBlocalplanner as the local_planner.

In order to have the full control of the trajectory I have divided the trajectory into lany short trajectory by using some WayPoints. As you can see in the following picture, when there is and obstacle on on waypoint, the DWBlocalplanner completely stops till the point would be free (the obstacles moves). I have put a very large radius for each waypoints (around 2.5 m) so as you see in the picture, the /movebase/DWBPlannerROS/Globalplanner already sends the trajectory to the next Waypoint but the robot completely stops.

By using the TEBlocalplanner as the local_planner the problem is solved but I want (for certain reasons) use the DWBlocalplanner.

I was wondering if anyone can help me to understand how to fix this problem.

image description

Thanks,

Asked by Mobile_robot on 2019-01-23 05:32:01 UTC

Comments

The first waypoint is the blue arrow and the second waypoint is at the end of the red line?

Asked by David Lu on 2019-01-24 11:50:44 UTC

the second one is an other blue arrow on the left (same direction of the red line) which is not in the figure because it is a bit far.

Asked by Mobile_robot on 2019-01-24 11:54:55 UTC

How are you sending each new waypoint? move_base_simple/goal ?

Asked by David Lu on 2019-01-24 15:06:09 UTC

For our project, we need to control the global_path. As you know better than me, at the current situation of the base_global_planner we can not create a navigation_corridor. Therefore, we made a package beside which create waypoints as temporary Goals with a distance tolerance.

Asked by Mobile_robot on 2019-01-25 03:51:42 UTC

In the figure, as you see, I have augmented the acceptable distance to achieve the first WayPoint (I belive 2m) so if the robot will be in the circle of the waypoint it consider as achieving the waypoint (this is why the RED path is already changed through the next WayPoint.

Asked by Mobile_robot on 2019-01-25 03:53:52 UTC

So the problem is that if there is an obstacle at the position of a waypoint, the DWB_local_planner slows down and does not achieve to get near the waypoint, and if it gets close to the waypoint it does not consider this as a achieved Goal.

Asked by Mobile_robot on 2019-01-25 03:58:11 UTC

That doesn't answer the question. Are you publishing the goals via a particular topic, or using the action server, or something else?

Asked by David Lu on 2019-01-25 09:33:22 UTC

Sorry for my late answer, as I am not the person who developed the WayPoint block I will update my question as soon as I go the answer of your question.

Asked by Mobile_robot on 2019-01-29 10:10:15 UTC

Answers