This thing is made with OOML (V2.0) http://iearobotics.com/oomlwiki/doku.phpI have kept the main structure and I have added a little of light to my prototype. In this way you can enjoy in the darkness solving a labyrinth, for example.I have used to do this derivative model:1 x Arduino UNO 1 x Bluetooth Arduino Module 2 x Futaba 3003 2 x Ultrasonic Sensors (Link: http://www.seeedstudio.com/wiki/index.php?title=Ultra_Sonic_range_measurement_module) 1 x Protoboard 2 x 9V power batteries 2 x red LEDs 2 x yellow LEDs 2 x green LEDs 3 x resistors (220 ohms aprox.)In the next link, it is the first training video: http://youtu.be/-5mcAUBTQyI?hd=1First steps to start in the OOML world:Install OOML library following the instructions of: http://iearobotics.com/oomlwiki/doku.php?id=download:startThen, compile the ProtoBot using cmake (you must set the OOML include dir and OOML Libraries dir). Run the protobot build program. It will generate the OpenSCAD files.Building instructions:1) Print the original chassis of Protobot. 2) Print the sensor plugin to ultrasonic sensors. 3) Take an Arduino UNO and a Protoboard to mount the main body. Use several spacers to separate from the Protobot body. 4) Take the two Futaba S3003 Servo Motors to mount on back side of the Protobot body (note: there is to hack this kind of servos as explain in the next link - wiki.darkomen.es/index.php?title=Taller:Usando_servos_skymega - in Spanish) 5) Connect the ultrasonic sensors and put together the sensor plugin. 6) In protoboard, connect 3 LEDs (R-Y-G) in one side (right) and the other 3 in the other side (left). Be sure that resistor are well setting. 7) Load the Arduino program (RPMBot.zip). 8) And, as say my friend pmarinplaza. To enjoy!!Next link show how RPMBot works in a circuit: http://youtu.be/JBdg2aSmYksNext link show how shine RPMBot in the darkness: http://youtu.be/h06TThN6S5E?hd=1 http://youtu.be/GndYlAXmCaM