Langhorne - differential drive robotic base

Apologies for the poor dae file preview, the second image in the gallery. The file isn't playing nice with the Thingiverse Universe. I've sent a message to their support group and will adjust as necessary.
This is a low cost, medium duty, differential drive robotic base that incorporates a Kinect camera, Power Wheels gearboxes that have been modified to include quadrature encoders, 12.5" wheels and tires from an electric scooter, a Pololou h-bridge motor controller, a Robogaia encoder counter, a Mean Well DC-DC power source for the Kinect, a Pololu IMU (inertial measurement unit to assist in localization), an arduino mega and a Dell Inspiron laptop running ROS (the open source robot operating system). The total cost (minus the laptop) was less than $700.00 US. It's been in the works for about six months now and is running ROS (the open source robot operating system).
This has become is a quite complicated project. It was initially envisioned as a robotic base capable of carrying a