Making the robot go straight on an empty map [closed]

asked 2011-07-28 15:51:04 -0600

PKG gravatar image

This is a sequel to this question .

My big problem is: I need to get the robot , whose configuration files are given in the question above, to traverse a distance of around 20 m in a straight line (or a close approximation to it), through move base. To this end, I gave an empty map here in its map server. I also changed the config files given in the earlier question, where appropriate, to have a large map like this: ... static_map: true rolling_window: false width: 2000.0 height: 2000.0 resolution: 5 origin_x: -10.0 origin_y: -10.0

My understanding is that this provides a large static map of size 2000*2000 divided into grids of size 5 m on a side. I also disabled rotate recovery by setting recovery_enabled to false. I am publishing constant, large values (around 100) in /scan's intensities and ranges, like given in the tutorial.

When I run the launch files and send a navigation goal of (20,0) [ the robot starts at (0,0)], move_base spends a long time in rotate recovery and avoiding collisions. This is true even for small goals , say (2,0). I can't figure out why. Further rostopic echo /move_base_node/navigation_local/obstacles gives cells= []. My rviz doesn't work, hence I had to resort to this. I don't know whether the png map I gave in the map config files has to be filled with particular values - I'm dumping the png here for what it's worth.

What I'd like to know is how to have a huge, 100% empty map, no obstacles at all, so that move_base just goes blindly straight ( in a consistent way, time after time) to the target, and spends no time at all avoiding obstacles. I am willing to change any map params or config params (except velocity and acceleration thresholds) to achieve this.

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Closed for the following reason question is not relevant or outdated by kwc
close date 2012-02-29 07:50:48

Comments

Just to get it right. You are trying to disable all of move_base's functionality just to move the robot straight. Why not just implementing a simple node that sends velocity commands directly to /base_controller/command?
Lorenz gravatar image Lorenz  ( 2011-07-28 20:52:34 -0600 )edit
Well, the point is to get move_base to do it. I need to extend this later to obstacles, and I need to test out move_base in this simple scenario first.
PKG gravatar image PKG  ( 2011-07-29 03:37:31 -0600 )edit
Dumping a PNG image to Pastebin doesn't make much sense now, does it? Perhaps if you could upload the image somewhere else, people might be able to help you.
Martin Günther gravatar image Martin Günther  ( 2011-08-07 23:15:45 -0600 )edit