Robotics Lab Preparation 1: Learn ROS


Due: Friday, May 12, 23:59:59. Do it asap - you'll need it for the May 6 lab already. Install ROS already!

Policy on plagiarism

This is an individual homework. While you may discuss the problems of this homework with others, at no time should you let any other person type the commands for you or use other persons computers for this homework. We will detect plagiarism using automated tools and will prosecute all violations to the fullest extent of the university regulations, including failing this course, academic probation, and expulsion from the university. If you have technical problems with completing any of the tasks on your own computer (e.g. because your Linux is not running {properly}) let us know in advance and we will find a solution!

Robotics Labs

These labs are for SI100 students only. See RoboticsGroups.pdf for your group and slot.

Learn ROS

The goal of this praparation is to get familiar with ROS. ROS - the Robot Operating System - is a set of software libraries and tools for writing robot applications. It features drivers and state-of-the-art algorithms as well as powerful developer tools and is open source. We will be using ROS to program the robots in the practice sessions.
You should learn the basic principles of ROS: Messages, Topics and Nodes as well as how to replay sensor data using rosbag and how to visualize the sensor data using rviz. You can use any source you want for learning about ROS, but I recommend the official documentation and tutorials:

Part 1: Learn about ros messages, ros topics and rosbag

Part 2: Learn about rviz

Hints for part 2: To display the odometry you need to add a "Display" of the type "Odometry". So in the Displays dock of the rviz application click on "Add" and select "Odometry". In the "Displays" dock you also see a new "Odometry" entry in the tree view. Expand it and enter the topic (name) for the messages that you want to display. Hint: If you click on "Topic" while the bagfile is playing you can simply select a topic rather than having to type the topic in by hand. You can also play with the other parameters in the tree view (e.g. try to adjust the "Length" to 0.1.

Part 3: Prepare for the lab session


The gradebot will check the existence of your checked files. Still the TA and teacher will check every image and the the python files manually if they meet the tasks. The scores could be manually altered (lowered) if the requirements are not met (for example rostopic echo is not showing anything in part 1 or the points are not visible in rviz in part 2). This will happen after the due date.

Getting Help

If you have any questions or problems with this homework please try to get help from the other students first, ask questions on the forum and search the Internet for solutions. A great source for information is for example the ROS answers website.
Additionally Prof. Schwertfeger will be available for answering questions and to help during his office hours.