Lego PC Bot

The parts used in this construction are:

1. Lego NXT kit with USB cable ~ $250.00
2. Logitech camera ~ $100.00
3. Asus Eee Ultra Low Cost PC ~ $350.00

The total cost of the platform comes to $700.00. With some price shopping and camera substitutions that cost can be reduced by about $100.00.

click on image for larger view

Construction

The Lego NXT kit while very flexible is not the strongest construction material to use when creating a robot to hold significant wieght. Thus the choice of the Asus Eee is largely based on weight. There are some other models of PC based robots constructed using the NXT kit that can be seen in at the following sites:

Mindstorm NXT + Eee PC = Good Times - A robot using the NXT as only an interface from the motor’s/sensors to the Eee PC using RoboRealm.

BB Vision Platform V1 Mounting a laptop ontop of a Lego robot using a USB camera and RoboRealm!

Lego Mindstorm carrying Acer Aspire An assembled structure to use as testbed for researching work.

Which are equally as good and can be used as additional inspiration during your construction.

Some of our requirements while building this robot were:

1. The robot must be built with only one kit's components.

2. No additional parts outside of the kit are to be used in platform construction (besides the Asus and Camera).

3. The laptop screen should be open and visible when in operation.

4. The keyboard should be able to still be used when in operation.

5. The laptop should be able to receive wall power without requiring removal of the laptop.

6. Switching batteries for the NXT should not be an involved process.

7. The camera should be attached to the front of the robot looking towards the ground.

In addition we also wanted to not introduce too much weight so that the robot would still allowed the robot to run over apartment thick carpet to ensure home use.

The most difficult process during construction was to ensure stability of the NXT system. Since a wide base (relative to the NXT) was require in order to hold the laptop the robot construction is inherinately unstable and has a lot of "give" within the structure. After many hours of stabilizing and suring of the construction the system runs reasonably well but will tend to disintegrate in various places if the robot hits an unintended obstacle. Thus, while the platform is a great experimentation platform, it is by no means capable of running for extended periods without requiring some human "tweaks" to secure the less reliable parts of the construction.