Implementing basic roam/avoid behaviours?

Question

Hi,

Looking for advise on what is a reasonable approach re: initially implementing a simple roam/avoid behaviour?

I do want to get this to progress to autonomous map building and navigation. I'm not sure what the best way to build up to this.

One way I know I can achieve this is to have a node subscribing to the laser scan and issuing fwd/left/right/rev commands depending on the distances reported from the laser scan. I wanted to know if there is a more "out of the box" ROS way to achieve this?

I have the raw messages and topics available (tf, odom, cmd_vel, laser_scan) and I've used "steering" in rqt to drive the robot and have looked at the links below, not sure if they are quite what I want at the moment (I know I'll need them later)

http://wiki.ros.org/move_base

http://wiki.ros.org/navigation

Thanks

Mark

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Originally posted by MarkyMark2012 on ROS Answers with karma: 1834 on 2015-02-03

Post score: 0

Answer 1

We did something similar in a robotics project some time ago. Our nodes for basic obstacle avoidance and autonomous mapping can be found at http://wiki.ros.org/nav2d. Maybe this can help.

There are 3 particularly important packages/nodes:

• nav2d_operator (basic obstacle avoidance) drives in a desired direction avoiding anything in the path
• nav2d_navigator (path planner) uses a map to navigate to a given goal
• nav2d_karto (slam) generates a map of the environment while driving

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Originally posted by Sebastian Kasperski with karma: 1658 on 2015-02-03

This answer was ACCEPTED on the original site

Post score: 1

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Original comments

Comment by MarkyMark2012 on 2015-02-06:
Hi Sebastian,

Thanks for this - which node is responsible for just roaming around (Will is just issue drive fwd until the sensor detects an obstical adn then turn away?)- from looking at is it its building a map regardless?

Thanks

Mark

Comment by MarkyMark2012 on 2015-02-06:
Thanks - I'll start off looking at nav2d_operator and see how I get on.

Comment by MarkyMark2012 on 2015-02-09:
Hi Sebastian - where would I find this cmd.h file - getting compilation error

Thanks

Mark

fatal error: nav2d_operator/cmd.h: No such file or directory
#include <nav2d_operator/cmd.h>

Comment by Sebastian Kasperski on 2015-02-10:
This is a ROS-message header, which should be created during the build process and go into ...catkin_ws/devel/include/nav2d_operator/cmd.h