MegaMaid
It's MegaMaid! She's gone from suck to blow!
Hi! I'm MegaMaid. I was built by my slaves Nirav Shah, David Euresti, and Dan Adkins. They worked hard on making me the only shooting robot in this year's competition.
So early in the competition my slaves got together and thought of what kind of strategies. Dan coined the term Nega-Bot (a robot that would run down the flat side and dump negative balls into the opponents bin. They didn't like that plan because it was too simple and boring. They were probably right.
In recitation they heard from Grant that he would like to see a shooter. So David came up with 5 different ideas for shooters. One had two wheels mounted vertically which propel the balls up into the air. Unfortunately the wheels given too us were either too big or too small for this function and so they either locked the ball in place or didn't shoot it. Finally David came up with the lawnmower idea. Using two 40 tooth gears and three shafts David built a shooter (which coincidentally resembled the lawn mower that was in his house) At the right height it can shoot balls along the ground to speeds which are good to not bounce right out of the bin.
So then the problem became how to move the balls from the front to the back of the robot. They devised a treadmill with rubber bands but they found out that it was illegal. So they went back and thought about it and came up with an actual treadmill made with treads.
So now came the problem of making me move. They built an adder/subtracter which was an amazing device. It took two inputs A and B, and outputer A+B in one side and A-B in the other. So if you power A you get A on the left and A on the right. So you drive straight. If you power B you get B on the left -B on the right. So you turn in place. It was such a cool box we called it the God Box. Unfortunately it neve made it into me. It was just too big. But I flirted with it a couple of times.
As it turns out the added another shooter in the front so that I would suck the balls into the treadmill. That's actually what makes me look so menacing.
So I employ a PosaBot strategy. I first race backwards into the wall. Then I turn and go backwards to try to push the balls into the bin. I then go down the ramp and pick up those four balls in the process. I sit a little bit to see if I can shoot the balls out and up the ramp. I then turn 90 degrees and head to the wall picking those four balls in the process. (My blower is set to reverse and the treads are stopped so that I won't shoot balls and they won't get stuck in my treads) I drive backward to hit the wall and turn 90 degrees so that my front is facing the opponent. I sit and try to shoot the balls up the ramp again. After doing that most robots would stop but I say "Hey! There might be some balls that I missed" So I turn around again and try it again until my time runs out. It makes me quite persistent
Here you can see me going for the extra four balls at qualifiers. I did pretty well that round and scored 12 points. My slaves seemed even more excited than I was they were jumping up and down.
So I have the sucker in the front. The blower in the back. The treads up the middle. My wheels are driven at a 1:81 gear ratio. And we have nitro. The sucker was at 1:3. The tread at 1:27. And the blower was at 1:2.5 so that the balls would make it all the way up the ramp (This employed putting a 24 tooth gear on a motor). So I had five motors.
On the sensors side I had a lot of sensors mounted that weren't used. I had 4 keyboard switches. Those were useful to tell if I had hit a wall. I had four Photosensors put on top to determine which way I was oriented. One light sensor underneath to signal the start. Two shaft encoders which we put on the wheels to turn. Not to drive forward just to turn. I had three reflectance sensors which my slaves tried to do line following with but I refused.
I also carry two passengers on my front. Laura and Church boy. Laura was the girl who so joyfully gave us the lego woman (only Lego woman in the contest) to put on our robot. And Church boy is the nickname of the guy she's in love with. If you think you are Church boy be a gentleman and give her a call.
So the day before qualifiers my slaves were trying to make me go straight. "But if the Left gear train is the bad one why does it steer to the right" They had forgotten one important aspect. I was very heavy on the right. They tried to shaft encode me but they were trying to make me run too fast and shaft encode. I didn't much appreciate that. So I wasn't going straight and they had almost given up on me. Then someone yelped, "wait what if we power the motors differently to go straight." So Dan wrote a program and with the pot calibrated how much power to give each motor to make me go forward and to make me go backward. And life was happy. Until contest night.
I ended up with a 3-2 score and made it al the way to the 5th round. I was content. My slaves were shocked at their "bad luck" "Oh well," I say. I'm still a cute looking machine.