The 2 12V DC motors are controlled by Parallax Motor Controllers. The Motor Controllers receive a PWM (pulse width modulation) signal from the Micro Controller (PIC18F 4550). The signals are sent to the Micro Controller from a Windows XP Tablet PC. The user inputs the speed and direction on the PC’s keyboard (via a remote desktop connection) and the data is sent to the Micro Controller via a COM port.
A Cool Fact:
The robot has a laptop on it that is connected to WiFi allowing the robot to be driven remotely from anywhere on the internet. You can call the robot on skype and view its webcam while you drive it over Remote Desktop or VNC Viewer.