squirrel_nav

Repository for navigation related SQUIRREL packages.

Requirement

Install the package dependencies running

rosdep install --from-path squirrel_nav -i -y
sudo apt-get install ros-indigo-sbpl

In order to properly generate the dynamic reconfiguration files, setting execute permission to the files contained in cfg folder might be needed: run

chmod a+x cfg/*	

from the home folder of the package.

Creating a 2D Gridmap

Run the mapping routine by executing

roslaunch squirrel_navigation gmapping.launch 

The map created can be then visualised in RViz. The robot should be teleoperated to explore the area. Once the map of the scene is correctly computed, it can be stored running

roslaunch squirrel_navigation gmapping.launch

An rviz configuration file for visualising the current map generated can be found in the git repository IN squirrel_navigation/config/robot1/rviz/rviz_hydro_gmapping.rviz. You should see a small part of a map. Move the robotino with the joystick to complete the map. If done, save the map with the following command:

$ rosrun map_server map_saver -f [mymap] 

where [mymap] should be replaced by the correct path and filename. mymap.pgm and mymap.yaml are created in the folder where the above command has been executed.

Move the map files into the folder navigation/squirrel_navigation/maps and create a symbolic link to the map:

$ roscd squirrel_navigation
$ cd maps
$ rm default-map.yaml
$ ln -s mymap.yaml default-map.yaml

Be sure that both the .yaml file and .pgm files are stored in the same folder.

Starting The Navigation

$ roslaunch squirrel_navigation navigation.launch {map_file:=[mymap.yaml]}

The argument map_file:=[mymap.yaml] can be omitted and the map pointed by default-map.yaml is loaded. In case the map's file is specified, [mymap.yaml] has to be replaced by the recorded mapping file. You have to use the full path to the mapping file, even if the yaml file is in the current working directory.

Localising in a 2D Gridmap

Set at first an estimated pose with the button 2D Pose Estimate and move the robot around the map to localise the robot. To start the robot in the last pose, set use_last_pose parameter to true in squirrel_2d_localizer package.

Performing a navigation task

After that, you can send a navigation goal via the rviz button 2D Nav Goal. The robot should now move to the goal.

Notes on navigation

The setup is meant for a robot provided with

• A laser rangefinder, used for localisation and obstacles mapping
• A depth camera, used for obstacles mapping and 3D navigation