Turtlebot Maze Solving with ROS

Exemplary code Autonomous Robotics Lab

@ Celi Sun @ Nov, 2017 @ Brandeis University

To nagivate turtlebot solving a maze, we have:

• main
• scan twist center control
• policy
• helper controller

The scan twist center control is receiving messages, processing message raw data, and publishing reaction messages once activated. It is also registered with a policy and an optional helper controller to help it make decisions of what action to take in response to the incoming message it receives, and therefore, eventually, navigates a turtlebot out of maze.

The repo here gives the exemplary code of solution and the default policy we provide is LeftOrRightHandRule, but you are more than welcomed to add your own policies (extends our Policy class). To add, put your policy script in the policy folder, and make the center control "know" it, and get it registered in the constructor to make it work.

Oct/2017

---

Run solution on your own labtop

Clone repository

You can clone this resiporoty by git to your own workspace by:

$ cd ~/catkin_ws/src
$ git clone https://github.com/campusrover/CourseExemplary_TurtlebotMazeSolving.git

Go back to catkin_ws and build the packages in the workspace by running catkin_make command:

$ cd ..
$ catkin_make

Configure IP address of labtop & turtlebot for ROS

To use ROS to control your turtlebot, you always need to set up the connection between the turtlebot and the roscore running on your laptop by configuring the IP address for each other.

On terminal,

$ ifconfig

In pop-up window, find the IP address of your own labtop/turtlebot shown after the last 'inet addr'.

Then, set up with the IP address you found

$ gedit ~/.bashrc

In pop-up .bashrc file, change the address of ROS_MASTER_URI (where the ros core is) and ROS_HOSTNAME (where your labtop is, can be same as ros core), but remain the port number, in this example '11311', unchanged. For example, if your laptop IP address is 129.64.147.246, change the following as:

export ROS_MASTER_URI=http://129.64.147.246:11311
export ROS_HOSTNAME=129.64.147.246

After, close the file and source the bash file by running:

$ source ~/.bashrc

Do the same on your turtlebot, however while the master IP ROS_MASTER_URI is still where the ros core is, ROS_HOSTNAME is the IP address of the turtlebot itself (can be checked out by ifconfig).

Ready to run

Put your turtlebot in the puzzle, launch your turlebot and run the solution:

rosrun CourseExemplary_TurtlebotMazeSolving main

Now watch how the turtlebot solves the maze !