Hello, here is an article on the creation of an autonomous mower, a first embodiment of a project based arduino uno bennurre.
MEG motor propulsion (engine essuis ice), cutting motor brushless 1000KV, obstacle detection by three sonar sensors and 2 front collison.
Energy provided by 2x 12V 7Ah lead acid batteries for a total weight of 10Kg robot.
On the blog: http://bennurre2.blogspot.fr/
you will find the entire code, numerous pictures and videos ...