sherlock_slam ROS package

This repository represents the sherlock_slam ROS pacakge, the package that configures and launches SLAM task via gmapping ROS package. The sherlock_slam package is intended for ROS Melodic. The repository needs to be cloned to the catkin workspace on the robot (no need to clone it to the PC) and compiled with following commands:

cd <catkin_ws_dir>/src
git clone git@github.com:minana96/sherlock_slam.git
cd ..
catkin_make

Dependencies

The package is dependent on gmapping ROS pacakge, which can be installed with the following command:

sudo apt install ros-melodic-gmapping

Package content

The package consists of three directories, namely, config, launch and maps.

config

The direcotry contains parameter configuration for gmapping ROS node in yaml format that are passed as arguments when the node is launched. The definitions of possible gmapping parameters are available in the ROS wiki page:

• gmapping_params.yaml: the default configuration used in all experiments, with particles set to 5 and temporalUpdate set to -1 (i.e., turned off);
• particles_30.yaml: the configuration used in the number of particles effect experiment, where particles parameter is set to 30 for respective treatments;
• temporal_updates_on.yaml: the configuration used in the temporal updates effect experiment, where temporalUpdate parameter is set to 0.5 for respective treatments (i.e., temporal updates turned on).

launch

The SLAM task is configured and launched via two launch files:

• sherlock_slam.launch: SLAM is launched on the local machine, with the possibility of visualisation in Rviz tool. If this option is used, both Rviz and turtlebot3_slam ROS package need to be installed with following commands:

sudo apt install ros-melodic-rviz
sudo apt install ros-melodic-turtlebot3-slam

• sherlock_slam_remote.launch: SLAM is launched on the remote machine that is passed as a parameter. If this launch file is used, it is important that the gmapping ROS package is also installed on the target remote machine.

maps

The directory contains the maps of the robot arena, created with gmapping while the robot is teleoperated around the environment. The map is represented with both arena_gallery.yaml and arena_gallery.pgm files. The instructions on how to create and save a map of a custom environment with TurtleBot3 are presented in here.