ROS

​ROS: Robot Operating System The Robot Operating System (ROS) is a set of software libraries and tools that help you build robot applications. From drivers to state-of-the-art algorithms, and with powerful developer tools, ROS has what you need for your next robotics project. And it's all open source. There are many versions of ROS corresponding to ubuntu version.As we are using 18.04 we needed melodic version.

http://wiki.ros.org/melodic/Installation/Ubuntu

Try running roscore to check if ros if installed perfectly or not.

System of ROS.

ROS can be visualized as a set of blocks called topics with all blocks connected to a leader block. There are two types of topics Publishers and Subscribers. Publisher publishes information encoded in various datatypes to the Leader from where Subscribers gets data. Nodes are the programs we write to establish this data transfer. Eg: I can get data from a sensor(fingerprint sensor) to some publisher where I can manipulate this data and sent to subscriber which drives an actuator(motor). The various commands and examples are given in this site.

http://wiki.ros.org/ROS/Tutorials

Do 1.1 All 20( You can go according to the sessions) . Things you have to keep in mind during the tutorial are given below.

Tutorial Notes ​

( ​ http://wiki.ros.org/ROS/Tutorials​ )

• Making a ROS workspace

We need a seperate space to work with ROS. Follow the steps in Creating a ROS workspace.

1. Use catkin build instead of catkin_make.

• Making a Catkin Package

Now we can have various packages inside our workspace for various purposes.For learning purpose make a package by following the steps given in the tutorial.

1. You need to write source devel/setup.zsh everytime you are going to execute a program.In order to avoid that you can write this on a document hidden in home. Press CTRL+H to reveal all hidden files in your home directory. There you will see a document named .Zshrc.Write the command anywhere in the file and save.

• Building ROS package

Follow the steps in ROS tutorial

1. Use catkin build instead of catkin_make.

For more information and understanding read https://www.cse.sc.edu/~jokane/agitr/​ ( Better read after this tutorial series gets over.So you can have a recap on what you have been learning)

Uninstalling ROS

Open a terminal and type

sudo apt-get purge '^ros-*'

This will remove everything regarding ros.