Building an autonomous robot using a rover platform and advanced electronics is not an easy job. Kevin asked me to build a robot that would follow its user. A companion, very much like a robo-dog. See the project log here.
Learn to connect a bluetooth module to an ATMega micro controller via the UART serial interface and even further, discover it using a bluetooth enabled Android phone. The 9600bps serial link established, can than be used to exchange data: read sensors or control the robot.