SLAM and navigation is achieved by using rtab-map, amcl and move_base packages in a simulated environment using Turtlebot3 waffle.
To install packages
sudo apt-get install ros-melodic-turtlebot3*
sudo apt-get install ros-melodic-rtabmap-ros*
To start mapping
roslaunch rtabmap_turtlebot3 turtlebot3_house.launch
roslaunch rtabmap_turtlebot3 demo_turtlebot3_navigation.launch
roslaunch rtabmap_turtlebot3 turtlebot3_teleop_key.launch model:=waffle
To start localization and navigation
roslaunch rtabmap_turtlebot3 turtlebot3_house.launch
roslaunch rtabmap_turtlebot3 demo_turtlebot3_navigation.launch localization:=true
To visualize created map
rtabmap-databaseViewer <database_directory>