Is there any other way to remotely control the raspberry pi? I built a 4 wheeled robot that is automated by ultrasonic sensors, yet today I have to decided it to make it remote controlled, what are my options?
In terms of remote control, you've got a few options. You could SSH into the Pi and control it via the command line. You could install VNC on the Pi and then use a client on another computer to connect to it that way. Alternatively, you could use a bluetooth dongle and pair up a Wii remote, PS3 controller or anything else that uses the bluetooth protocol. There are a variety of tutorials available online for all of them, so let us know if any of those take your fancy :-)