Mindboards

First off, sorry for being late. I had contacted BrickWorld to get some robot names for my competition videos, and they took a bit to respond. I also had some trouble editing the videos. Note to self: Only use Windows Movie Maker in Win-7, NOT Win-8. Anyway, on to business.

BrickWorld Chicago goes Thursday-Sunday in the third week of June.

Thursday.

Whenever BrickWorld has a sumo, they do a workshop for people who don't have NXTs. I helped with that. The BOTS (Build On The Spot) Challenge was today. Basically, you've got 8-hours to build and program a robot for the years challenge, which you don't know until you get there. Here are this years rules: https://www.dropbox.com/s/hd87dhdc4xsn4 ... _Rules.PDF Sorry for the poor scan quality. That papers been sitting folded up under a pile of junk since shortly after BrickWorld. Here's the video of my robot:




The first round was a practice run. The next three clips are of the actual contest. I lost, due to a misunderstanding of the rules. I thought the cubes would be scattered across the ring, but they were not.

I also built a boat on Thursday, using hulls I had bought from a vendor earlier in the day. More on that later.

So, Thursday done, I finally got to bed around midnight, as with every day I was there.

Friday.

Friday starts at 6:00AM, and me waiting two-hours for them to unlock the display halls. At least I got to play Portal 2. After they were unlocked, I finished the aforementioned boat, and worked a bit on my Satellite Repair Bot. After that, there was the boat race, which, unfortunately, I didn't get any videos of. However, I do have a video of my boat on the lake by my house:




Friday night I spent a couple of hours on my Satellite Repair robot, almost finishing it. I also played a simplified round of SRR (Super Robo Rally).


Saturday.

Ah, the first public day! I was a exhibitor, but it seems somebody forgot to take pictures of my table. I'm talking to you, Dad. A couple of hours after opening was the Super Sized Sumo Event. I had two robots; Juggernuat and W.E.D.G.E. Juggernaut took one of the fourth places, and W.E.D.G.E. snagged second! :biggrin: :biggrin: All my sumo clips compiled into one video:




Saturday night was taken up by another game of SRR, but this time it was the full game, so it took about 3-hours, but boy was it fun! Bryan Bonahoom, BW cofounder, walked in when it was about half over and put in the TECHNIC set #8066 in as a prize, but then Steve said (he was near the finish, of course) that first place got to keep the board, and second place got the set (thanks, Steve!). I won second place, and the set has some very good elements I've been missing.


Sunday.

*sniff* :crying: The last day of BW. The Satellite Repair contest was today, and I finished mine just in time. Here's my videos:




Notice the lack of a programmable brick on mine. It was mechanical.

Pack it on up, move it on out. Bye bye BW, see you next year!




I'll be posting individual messages for each thing I made.

If you'd like to hear more about anything, just say so. If you think I missed something, also say so.

Juggernuat

Juggernaut is a LEGO MindStorms RCX LEGO sumo robot designed to compete in the BrickWorld Chicago 2012 Super Sized Sumo event. It placed fourth! I actually kind of made it as a joke. There was a time when I was stuck on another robot, so I built and programmed this in about a day. I didn't expect it to do well at all, but it actually came out at the top of it's pool! :bigthumb: And, managed to tie a bout with the deadly Decoy!

Front.


Back.


"Feelers".

Juggernaut found it's opponents using these "feelers". Each one depresses a touch sensor when bent. The rubber bands pull them against the buttons, and provide some resistance against false positives.

The strategy was like this: At the start, it would turn towards the opponent, and start moving forward. If it hits the edge, randomly choose which way to turn (it only had one light sensor) and for how long. If the left sensor it hit, turn left. If the right sensor is hit, turn right. If both are hit, keep going straight.


Wires, start button.

The tangle of wires that results from 4 PF motors, 2 converter cables, and 3 sensors. Also, the start button. The start button is attached to the same port as the light sensor, so when it's pressed the amount of light read equals "100". This doesn't interfere with the match, since that button is only used to start it. That's one advantage the RCX has over the NXT, is it's easy to multiplex some sensors. When the "run" button is pressed, it waits for you to press the left feeler, right feeler, or this button. This determines which way it turns at the start, and for how long. Left feeler = left, right feeler = right, button = back. After that, you press the button shown in this photo to start it if you didn't choose to go backwards.


Motors.

Juggernaut is driven by 4 PF-M motors at a 5:1 ratio, giving a final tourqe of 72.6 Ncm. Even when the motors are coasting, I can hardly turn the wheel!


Program.

Very interesting!

Actually, you can "multiplex" light and touch sensors on the NXT, as with the RCX.

Be careful not to over-draw from the motor ports. Even one PF-M motor is enough to get the driver hot, and I've never tried using a second one. IIRC, the RCX motor drivers are rated for about 300 or 350 ma. A stalled PF-M motor draws about 800 ma (according to Philo's PF page).

Risk of overload aside I like the simplicity of it. Often simple is the best way to go.

mattallen37 wrote:Very interesting!

Actually, you can "multiplex" light and touch sensors on the NXT, as with the RCX.

Be careful not to over-draw from the motor ports. Even one PF-M motor is enough to get the driver hot, and I've never tried using a second one. IIRC, the RCX motor drivers are rated for about 300 or 350 ma. A stalled PF-M motor draws about 800 ma (according to Philo's PF page).

Thanks!

I knew that, but what I meant was it's easiest to do with the RCX.

I hadn't thought of the overload, but The motors never stalled so I didn't have any problems.

W.E.D.G.E.

"W.E.D.G.E." stands for "Wheeled Envoy Doggedly Gyrates Ecstatically". It has a wedge (duh!) made out of LEGO Racers ramps, allowing for a very thin edge and superior wedging ability. This robot went through several revisions, with this one being the best. I went through about ~4 designs prior to this one, having to completely tear apart each previous design.

Front.


Back.


Bottom.

This pic shows the light sensors (one is the LEGO color and the other is the LEGO light. I didn't have two LEGO lights available at the time) and the drive system. Notice the three motors. More on that later. Also the white beams sticking out from the middle motor. Those were added at the last minute to prevent W.E.D.G.E. from doing a wheelie when going forward. The balance was too far back to prevent it, so I added the beams.


Motors.

W.E.D.G.E. is driven by three NXT motors. One on each side, going into the two sides of a differential gear, and one in the middle connected to the casing of the gear. This allows the middle motor to turn on and help to push when it's charging. It just has to go the average of the speed of the other two motors. The wheels are the 81.6 diameter road tires from the Nitro Muscle.


Ultrasonic sensors.


Program.

Paddle-FAIL

Paddle-FAIL was designed and built in less than an hour, on the Thursday of BrickWorld. I saw some cheap hulls at a vendors booth, and decided to make a boat. It had no steering control, not even a rudder to keep it straight. Well, I guess that's what you get for something made without thinking .

Overview.

Notice the Scorpion Pilots! (eh, you had to be there.)


Drive System.

Each wheel was driven by three LEGO Mini-Motors geared 3:1. Two old-style AA battery boxes were wired together to increase the Amperage, sealed in a plastic bag, and connected to the motors. The motors are water-resistant, so the amount they got, they still run just fine. The connections are a bit rusted now, though .


Batteries.

Like I said, the battery boxes were sealed in a plastic bag, rubber banded onto the boat, the end taped up around the power wires, and the power wires connected to a hub connecting all the motor wires.


Running.


Program.

None, yet. But I'm working on a port of RobotC that can be used to program plastic!

And now, last but not least, my personal favorite, PileDriver!!!!!

Designed for the Satellite Repair Challenge, PileDriver placed 2nd to Steve's "Columbia". It was a completely mechanical design, using a wind-up timer for the delay and pneumatics for the "descent". I gave everyone a good laugh when, during a test, mine fell from the top of the pipe and shattered, leaving the internal frame (it looked kinda like this. Except it was broken more.) still around the pipe at the bottom. The laugh was from me asking if it counted as "safe" if the minifigs were still attached to that frame. It was ruled that, if the main body was still attached, and the minifigs were all together and attached to that part, then it was safe.

Front?

On the front, you can see the PDI/SL (Pneumatic Descent Initiator/Satellite Launcher) the air pump, and the air tank. During a run, the yellow rubber-band hanging from the arm would be attached to a pin by the small pneumatic cylinder, pulling the square against the pipe. At the top, this would pull over across the pipe knocking the "satellite" off and flicking the pneumatic switch, extending the cylinders, which causes the wheels to lose contact with the pipe, thusly sending PileDriver into a free-fall!!


Back?

Here you can see the timer, and the other cylinder.


Drive.

PileDriver climbs using two PF-XL motors, one on each side, geared 1.8:1. They're each plugged into a PF AAA battery box through the timer switch.


Timer.

Originally, the rules stated that the robot must wait at least two seconds before starting to climb. Of course, after seeing Steve's robot, they abolished it . EDIT: I was just now told that they didn't change the rules, the rules were just stated so that it didn't specifically state that you must have a timer. It is made using this part. There is a 25:1 gearing in between the motor output and the switch. Fully wound, there is about a 2-3 second delay.


Bound & gagged.

My "method" of attaching the minifigs. Well, they never fell off!

On the origin of names.

Juggernaut: The definition of Juggernaut is "any large, overpowering, destructive force or object, as war, a giant battleship, or a powerful football team." Ignore the last two bits. I think that this was a good name, because when the wheels were in contact with the ground, and the inside not propped up, its pushing power was practically unstoppable.

W.E.D.G.E.: I don't know. W.E.D.G.E. stands for "Wheeled Envoy Doggedly Gyrates Ecstatically". I wanted to call it W.E.D.G.E., but wanted to also make it interesting.

Paddle-FAIL: I think this one is self-explanatory.

PileDriver: I called it PileDriver because, during preliminary tests, it would bounce at the bottom, mimicking the motion of the construction machine bearing the same name.

Thanks for sharing. Those are some pretty interesting MOCs!