NXT Catamaran

My FLL Team kids built the basic boat for their research project. They also did all the decorating. :)

I reinforced the structure using aluminum liftarms (from my store) as crossbeams between the hulls. I drilled out some of the studs on the deck of the boat and tapped the holes with cap screws into threaded beams to ensure the boat won't come apart mid-cruise.

The boat is currently outfitted with a Mindstorms NXT, two NXT motors for steering, two LEGO underwater boat motors for propulsion, an ultrasonic sensor and a Hitechnic Compass Sensor. I developed a navigation program that can steer the boat to any compass heading. It rotates the motors to bring the boat about until the desired heading is achieved. With the motors mounted one behind the other, I can spin the boat in place if needed and the motors will turn in opposite directions to obtain the proper heading. I've tested the boat navigation and the boat does float level and functions in completely still water.

TO DO Items:

1. Replace the LEGO prop motors with motors which allow me to control RPMs. The LEGO boat motors have two speeds - on and off.

2. Replace the NXT with a cheaper brain that I can protect from water damage.

3. Integrate IR sensors so the boat can navigate a course while avoiding IR beacons on the water.