This is the first robot I have ever made. 
In fact is just to motors and to bumpswitchs . When the robot hit something whit the bumpswitchs (depending on witch switch is activated ) one motor will reverse , causing the bot to go over obstacles. It cost aproximatly 15 $ CAN because I bougth all the parts in a RadioShit store and the prices where very expensive .

If you never tried robotics before , I recomend you to try this as a first project.
All details and a beautifull tutorial can be found on the Jeromes Demers website 
Here

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