I highly recommend the newer design: https://pinshape.com/items/476...
The idea here is to build a small collision avoidance X-Project using two d.c. motors as a starting point for a small self-driving car or other robotic project. Rather than buying all that expensive Arduino stuff, now you can have as good or better by 3D printing your own parts and using a RoboGuts™ circuit board instead ... and using the RoboGuts™ circuit board you can now easily add a voice to your projects. Bodies that will just slip over the top coming soon. The ExtendedZumoLaserPlate raises a build platform above and overlaps the wheels. This allows for bigger build-ups.