Team 404 Post-Nationals Robots+Strategies Reveal

Team 404 Post-Nationals Reveal

Now that Nationals is over and videos will probably be released soon, we’d like to post up our first ever robot reveal. Anyway, the level

of the tournament was quite high, and the competition was really intense. We were fairly suprised at how successful the tournament turned

out for us. The results were as follows:

The tournament champions were: 404, 12A, 404C
The tournament finalists were: 404A, 12D, 402B

Excellence went to 404A

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Here are some details of our 5 robots, and a discussion of the overall strategies we utilize.

Robot 1:

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Overall emphasis: Balance in Isolation

Chassis: x2 269 motors and x2 393 motors on 1:1.25 speed ratio.
Tower: x2 269 motors and x2 393 motors on 7:1 torque ratio.
Intake: 2x 269 motors.

Key features: “Virtual 6-bar”, raised chassis

Designed solely for isolation. Wins center 20" goals consistently, although it ties the goals every so often. For the arms, we created

what we call the “Virtual 6-bar,” which is essentially a combination of a 6-bar and a chain bar. It gives us most of the stability

afforded by 6-bars, and allows us enough freedom to gear the tower with 4 motors on a 7:1 ratio. We take advantage of a raised chassis to

give us an advantage mid to late game. Not excessively fast, but there is very little wasted movement so it’s pretty efficient overall.

This bot ranked 1st in Black Division, just barely passing 1200F after they tied with our 404E team. Although it went undefeated, its

ranking points were extremely low, as we focus on negating opponents’ goals moreso than doubling our own goals. This bot won the

competition with 404C and 12A. The closest this robot ever came to losing the 20" goals was during the Finals against 12D, which played

an autonomous programmed specifically to counter our autonomous.

Robot 2:

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Overall emphasis: Speed in Isolation

Chassis: x4 393 motors internally geared for speed.
Tower: x4 269 motors on 11:1 torque ratio.
Intake: x2 269 motors.

Key features: Chain bar, radially symmetric side roller intakes, raised chassis

Also designed for isolation. Basic chain bar design, built as light as possible. The 11:1 torque ratio is pretty slow for our tastes, but

our motors cut out the night before nationals and we had to change the ratio to compete (initially it was geared 7:1). More often than

not wins the 20" center goals, or at least ties. On a side note, our driver is one of the three girls on the team, and a first year

member at that. Really made us proud. Anyway, the intake uses a unique “flap” orientation to both improve intake and make scoring easier.

This bot ranked 11th in Silver Division after some very strange incidents. Lost twice in qualifications matches; lost to 1069 in one

match, and 404A with 12D in another. Competed with 40J and 4148H against 404A, 12D, and 402B in the Silver Division Finals and lost after

extremely close matches (1 point difference in one match).

Robot 3:

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Overall emphasis: Power in both zones

Chassis: x2 393 motors and x4 269 motors on 1:1.25 speed ratio.
Tower: x2 393 motors on 7:1 torque ratio.
Intake: x2 269 motors.

Key features: pneumatics launcher, raised chassis, 6 motor chassis

Can play both isolation and interaction, although we have recently taken a liking to playing interaction. With two air tanks, a six-bar

arm, and a hefty tower, the robot is pretty robust. Basically it has a LOT of pushing power, and the high traction wheels prevent it from

being pushed sideways. Inspired by Viewpoint 1437’s Z bot (good stuff). After they pushed us around one competition, we geared the

chassis ratio down and changed from a quad-omni drive.

High scoring robot, so it typically wins the center 30" and proceeds to block both the opponents’ robots. The pneumatics is used to

increase loading speed from interaction zone to isolation zone, so we can keep the gate closed and our alliance safe until the last 40-50

seconds of the match. It can also be used to instantly secure the opponents 20" when we play Isolation. Of course, raised chassis for the

multiple advantages it affords us.

This bot ranked 1st in silver Division. competed against 404, 12A, and 404C in the finals along with its alliances 402B and 12D. Won the

first match, but lost the next two. This robot also did not participate fully in the skills challenge because we accidentally missed the

time deadline, which is unfortunate as we spent several weeks perfecting a driver’s skills route. Was awarded the Excellence Award after

the tournament ended.

Robot 4:

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Overall emphasis: Early to mid game in interaction

Chassis: x2 393 motors and x4 269 motors chained 1:1.
Tower: x2 393 motors on 9:1 torque ratio.
Intake: x2 269 motors.

Key features: dual tread intake, 6 motor chassis, 6 wheel drive, chain bar lift

Okay, this bot is a complete 180 degree change from most of our robots. For lack of a better term, this bot is a “support” bot, as

opposed to the independently high scoring bots we usually design. It utilizes a chain bar arm which rotates over a very small angle to

increase our 30" lift speed. The front sprocket connected to the intake is smaller, allowing the intake to rotate and give us extra

height as the lift raises. 6 wheel drive gives us extra traction, while 6 motor drives gives us extra stall torque. Staggered high

traction wheels prevents the robot from getting pushed sideways. A jury-rigged weight block of sorts gives us the weight to push hard.

Intake is designed to quickly load the isolation zone with pieces from the pyramid.

This ranked 22nd in Black Division. It was selected as part of the 7th seeded alliance along with 4900 and 4405B and defeated the 2nd

seeded alliance comprised of 1200F, 40D, and 6813M. It was defeated in the Divisional Semi-finals against 4184G, 12F, and 402A.

The bot qualifies badly because it is EXTREMELY dependent on its alliance; it essentially acts as a power multiplier. It compensates for

its alliance’s weaknesses and negates its opponents’ strengths. For example, paired with a weak but fast robot like 404, it can typically

ensure a solid victory. Now, this robot sounds like a wallbot. However, a key difference between this robot and common wall bot designs

is its ability to score quickly. While it can’t collect more than two objects at a time, it takes advantage of its 6 match loads to

secure the center 30" goal and the interaction 10" goal. After that point, it prevents its opponents from taking advantage of their

negation and doubler barrels, and allows its alliance to double the isolation 30" and negate a possibly lost center 20" goal.

Here is the prime example of this robot’s efficiency. This robot with its alliances were able to defeat the second seeded alliance

(1200F, 40D, and 6813M) four times in a row. (If you’re wondering how this is possible, the matches went as follows: Match 1 Loss, Match

2 Tie, Match 3 Win, Match 4 win. At this point, the second match was contested, resulting in the matches resetting to Match 2. So…

Match 5 Win, Match 6 Win.) Essentially, this bot was able to consistently win the 30" center goal, then sit between the opponents’ two

starting tiles (not covering either tiles nor pinning either robot). Our opponents were then unable to double their isolation 30" or

escape the isolation zone to negate any of our goals. Team 4405B doubled our isolation 30" unopposed, and negated our lost 20". In the

final match, every single goals’ point differential was controlled by our alliance (which on its own also ranked low in qualifying

matches with a score of 1W-5L-1T). In short, STRATEGY IS EVERYTHING. In other words, just because a robot ranks low does not mean that it

is an inherently weak bot.

On another note, I know a lot of teams seem to dislike purely defensive strategies, and seem to categorize this robot as purely

defensive. I disagree. This robot was designed to score the 30" center goal FIRST. Then and only then does this robot revert to a

defensive strategy, in which it supports its isolation alliance via passing it game objects and interferes with its opponents. Yes, this

bot may be frustrating to compete against, but no more so than a robot that is several times more efficient at scoring. In other words,

this robot levels the playing field, rather than completely obliterating its opposition. With proper strategy, an individually low

scoring robot can exhibit its true potental and compete on par with an individually high scoring robot. We feel this is a positive change

in the meta game, and the visible change in the meta game after we utilized this strategy during Nationals seems to point to this.

Robot 5:

[Picture to be added]

Overall emphasis: Early and late game in interaction

Chassis: x2 393 motors and x6 269 motors chained 1:1.
Tower: x2 393 motors on 11:1 torque ratio.
Intake: pneumatics

Key features: pneumatics intake, 8 motor chassis, “the wall”, 36" reach

This is another rendition of our team’s interpretation of a “support bot.” This robot was designed specifically to support our isolation

robots. With a 8 motor chassis, this bot can push the majority of other bots (even strong interaction bots) and secures the center 30"

consistently (the only time it truly loses the goal is if we forget to pump the air into the pneumatics tanks…). Mid game is weak due

to the pneumatics intake, but end game is extremely strong for several reasons. 1) 36" reach allows us to negate or double a 30" goal and

protect the pieces. 2) 8 motor chassis allows us to run the end game strategy we used with our 4th robot, but with 33% more efficiency.

  1. we can selectively block sections of the field by actively reorientating our robot forward.

We have recently seen discussion of our “wall,” and heard other teams talking about it at the National competition. For those of you who

were not at Nationals and for many of you who were, we were seen “accidentally tipping” our own robot. This is incorrect. This “tipping”

is designed into the functionality of the robot. In other words, this tipping is not tipping, but rather a deliberate robot

reorientation. Far reach and exposed forward wheels allows the robot to “tip” forward easily and, most importantly, safely. We can then

extend the arm to create a fence of sorts. We can even drive forwards and backwards to reposition this wall. We were fairly amused as the

audience cried out as the robot “tipped” in the interaction zone, as they failed to notice the location of the robot’s “tipping.” This

strategy was used to great effect in the elimination matches, especially since we kept this ability secret until the last moment. By

doing so, we can strategically isolate various zones of the field (i.e. secure our isolation zone, trap opponents in their isolation

zone, keep opponents in our side of the field, etc.). If desired, we can drive forward and retract our arm, reorientating our robot into

its “scoring mode.” You can see a progression of our robot reorientating itself into its scoring mode here.


This bot ranked 13 in Black Division. It was selected as 2nd pick by 404 and 12A, and went on to win the National Championship.

On a final note, we’d like to thank all of our alliance partners, and all of our opponents for that matter. After this competition, we

have a much better idea of where we want our robots to be, and we feel that World will be an amazing competition, as it always is.
we would also like to thank 1069E and 3018 Techna PWN for lending us motors when one of our lift motors died, and the event coordinators

for making this such an enjoyable event.

As for our robot designs, any and all comments and criticisms are welcome. We will likely post or link to videos of our robots competing

in Elimination Matches. If anyone has taken videos of these matches, feel free to post them here.](

Although I’m not sure which robot is exactly which yet because the pictures aren’t up, the intentional tipping strategy is awesome. I may have to incorporate it into our robot.

i really liked your robots guys!!!

nice intro to the strategy me and TGN will have clips and vids posted soon
gets peoples noggins turning and warmed up :slight_smile:

the only issue for the tipping is that if a robot thats trying to get past rams full speed at your intake portion if your “Wall” how well does it hold?

(this should be expected because once robots run out of things to score, and you are purely playing defense, you should expect vigorous ramming and shoving)

overall great robot and im glad there are other teams out there that thinks about elite level strategies :slight_smile:

get on chatango sometime
it would be great to have a strategy discussion with you :slight_smile:

Thanks for the positive feedback murdomeek. I remember your team from Worlds last year; we were your 2nd pick in the 4th or 5th seed and lost to Green Eggs in the Divisional Finals. You’re strategies are always solid, and I would definitely love to talk strategy with you at some point.

As for how well our wall holds up, I would say fairly well. We took our interaction dual tread design (Robot 4) and rammed it against our wall, and it seemed to hold up just fine. Although to be honest we’re not 100% sure of how well it will hold up at Worlds, since the teams we used it against during the Elimination Matches seemed to just leave it alone. We will most likely make the design more robust than it already is just in case.

r u on right now?
get on chatango!

Um just wondering, how long does it take your robot to get up if needed? Also, I was a little surprised at your gear ratios. 404E seemed like such a fast bot in the livestream but it only has a 1:1 gear ratio? Oh and if 404 went against 404A for the 2 isolation goals who would win?

The reason 404E looks so fast is because it was designed with a very low CoG and is actually very light despite its pushing power.

The short answer is that it depends, on 2 factors specifically: 1) how well our drivers react to each other as soon as driver control starts. 2) whether or not the ball launched by 404A’s catapult secures the opposing 20" goal. The driver of 404 is typically more stubborn with the 20" goals, so that gives him slightly higher success rate over the catapult’s accuracy rate.

404a u deserved that excellence award!

Are the 404 teams coming to the World Championships? I’d like to see how we’d do against 404E. Our robot, too, is designed to win battles over goals, especially the center 30" goal. How much does 404E’s robot weigh? Ours is 25 lbs and has 4 393s on the wheels. It should be interesting to see how a match between us would play out. Overall, great bots!

what is the drive ratio?
if its 1.6:1 then you may be on the boarder line for the motors tripping out

Yes, all of our 404 teams are registered and going to world. As for the weights and pictures of our robots, we are still unwinding from nationals and will post them ASAP.

we have 4 393’s on the drive at 1.5:1 with 13.5 pounds and we still have stalling problems. is this normal?

You shouldn’t stall even using 2:1 for a 13.5 pound robot (unless pushed). You didn’t change the 393’s for power did you or that would be like 2.4:1. You should make sure that all your motors are running by unplugging one motor on each side and seeing if it still runs. Even one motor should be powerful enough for 1.5:1. Then you should plug the motors back in and unplug the 2 other 393’s. Otherwise you might have excessive friction on your base, which is stalling your motors (if your spacing is too tight for your wheels because you should be able to move them just slightly, or you over tensioned your chain)

Btw, back on topic. What happened with 404B? They don’t seem to be registered for the world championships, but they should have qualified through robot skills since they were 19th. Did they not feel like going?

We will definitely be coming to Worlds. So far we have qualified and registered 5 teams. In any case, we would also like to see how our “E” bot does against such a heavy bot.

Our “B” team will not be attending, because we do not truly have a “B” team. Our club works differently in that it operates as a collective; our members float between teams and work on whichever robot needs tuning up. Since we don’t have enough manpower to run a 6th team at Worlds, we decided to not register the B tag.

As for stalling with a 1.5:1 speed ratio on a 14 lb bot, I wouldn’t say it’s “normal,” but it’s definitely common. We ran a 9 lb bot on the same ratio with the same motor configuration and had similar problems. I’m assuming you’re not physically stalling the motors, but rather activating the circuit breakers in the motor controller. I suggest either internally gearing the motors to speed (which translates to a 1.6:1 speed ratio) or simply gearing the ratio down. You could also try looking at how you have plugged in the motors to the controller; try redistributing the motors to the two breakers so you don’t trip them as easily (the breakers are distributed in two sections, ports 1-5 and ports 6-10). Hope that helps.

The drive ratio is 1:1. It’s not the fastest robot, but the downforce gives it extra pushing power. We only have minimal stalling problems. When it does stall out, we push button 7U on our controller, which we’ve programmed to hold all 10 motors at 0 for five seconds, which allows our PTCs to reset.

Great! I look forward to seeing you! It’ll be nice to play with a robot that defends AND scores well.

Looking forward to seeing you guys as well! Come over to our pits and perhaps we can discuss strategies or simply chat for fun during lunchtime or something :smiley: You will definitely be surprised!! We are making lots of changes and add-ons to all our robots, so our strategies and designs will be significantly different (and better!) than what we had for nationals! :wink: