Question 1: What was the general strategy or plan behind your bot design?

Using a Spybot brick to build a sumo robot...

Question 2: What technologies/mechanisms did you use?

I used the Spybot's remote mounted under the robot set up to send an IR beacon. Using the 2 built-in receivers, Spybot can sense the target at left, left-of-centre, centre, right-of-centre, right. Then, with the built-in motors I was driving through a clutch gear a couple of polarity switches that powered regular LEGO motors from a battery box. And I used the bumper for detecting the edge.

Question 3: What was the most challenging aspect of construction?

Making the robot to react in time at the edge... And the weight limit made me use a small battery box and only 2 motors. Not verry powerfull...

Question 4: Are there any special features you care to talk about?

Spybot's proximity detection works pretty good. It has 3 zones: anywhere, there and here. Once in there and here zones, it can detect the direction as I explained above. As it was set up on my robot it could see easier taller robots or people's legs. The LED's and the laser combined with the sounds make a nice show. Using a shilded fiberoptic and a LEGO lamp the internal light sensor can be used. Maybe that one will work better...

Question 5: What surprised you about how your bot behaved/performed during the event?

A night before I just made it work good enough for the contest. But over there it didn't work. It did not had a single win. All because of not reacting fast enough to the bumper. But it is prommising... Next time I will have two of them!