If you are the original author, please access your User Control Panel and update it.
This is a very simple robot which only has two wheels made of old CDs. Its brain is a motoruino and uses a sonar to detect and avoid the obstacles. On the video you can watch him navigating around, using the battery wire as a support to keep the balance.
This is a companion discussion topic for the original entry at https://community.robotshop.com/index.php/robots/show/cd-bot