Team 39 building 469 stopper solution (Available in Las Vegas)

Guaranteed 2 on 2 solution available for purchase at regionals :wink: (just kidding but read post 10 or all for some additional constructive countermeasures).


CIM driven ducted fan package with on board jaguar and pig tailed wiring for quick attachment to your robot. Free Labview VI or programming support to control it. Unit weighs 5.8lbs including CIM motor.

Fan has optimized exit duct with wide vertical aperture to ensure maximum dwell time of the falling ball in the airstream.

And yes, the balls end up in opposition home zone but not in their goal.

If you feel that your robot needs the edge to defeat these endless loop robots, this is the solution for you. With easy attachment, and sure deflection this is your ticket for helping those alliances in need of serious defense.

If you are interested, please respond.
(Available for prompt purchase and return at the Las Vegas regional for teams interested. There will be a $5.00 restocking fee.)

Patent Pending.

That sounds like a great idea Frank, it would be very easy to implement, and we could literally put it on any team trying to duplicated 469 that is going to Vegas. Even a not so good robot could attach this thing and be a great contender. Great job. I can’t wait to see these things in the shop. Seams fairly simple and effective.

Sounds like a solid plan, but i believe FIRST does have rules against teams selling items like this to other teams… (Not Positive, but pretty sure)

There was some drama about this when team 221 llc came out, but they are not directly affiliated with the team i think, they are like a mini andymark.
However, you can make a whitepaper and show others how to do it, or just stick it on your alliance partner before elims reinspection?

Or you could have just not been serious this whole time and I cant pick up sarcasm? Im good at missing things like that :slight_smile:

We figured this would be a productive outlet for some of the serious fan technology developed during lunacy.

I recall a CIM solution on our field in Atlanta with 7 lbs of thrust. For an orbit ball deflector, we had tested but eventually decided not to use a FP motor swinging an 8 inch propeller. Perhaps even a FP coupled correctly with its 185 watts output might even be enough for this disruptor. The lower speed CIM is a better candidate for the bigger fans as it’s speed is 3x slower than FP and requires no gearbox.

The key to deflecting the soccer balls enough to disrupt accurate scoring will be high air velocity and some vertical aperture to the airstream. This could be an attractive strategy for those robots lacking ball handling mechanisms. Built right, it is a sure ticket to finals against an endless loop bot.

Not sure this really needs a white-paper as the concept is fairly simple. Put fan low and run lightweight duct up to the 51 inch mark. Lots of RC aircraft calculator programs on the web for matching motors to props.

469 needs to trademark their name and number as quickly as possible. They could cash in on all the hype surrounding them.

I’m even sick of hearing about us…

Or teams could just prevent them from locking onto the tower…I already know of several teams making anti-guerilla autons

Then quit now before it’s too late! :yikes: :ahh:

That sounds like a great idea Frank, it would be very easy to implement, and we could literally put it on any team trying to duplicated 469 that is going to Vegas. Even a not so good robot could attach this thing and be a great contender. Great job. I can’t wait to see these things in the shop. Seams fairly simple and effective.

Mason, Mason, Mason…you move to the Left Coast and immediately start thinking like them! ::ouch::

Don’t forget your MI roots and don’t fear…The contraption was invented in MI and the countermeasures will be deployed in MI. So hang tight and watch what we do! :yikes:

64 teams at States…only 2 will be their partners…that leaves 61 of the best MI teams that will want to have a defense. (PM me the cost of your fan :slight_smile: )

Good to see everyone on both right and left coasts picking up the gauntlet on this.

Our post was in reaction to the doom and gloom outlook over this at the time I made the original post. Our team was even pondering doing a variant within the 65lb hold-back but that is largely scuttled.

The fan and several other schemes can deal with this. The real trick is how to come up with a scheme that will not just simply convert a total annihilation situation into a sure defeat with two 469 partners on on 1 opposition but with less points margin for 469ers. The trick is to level this to a 2 on 2 or a 1 on 1 and have a fighting chance.

The fan scheme is deployed when 469 has engaged to the tower possibly irreversibly. Not clear that the 469 can un-deploy the mechanism in order to abandon the tower if they find themselves ineffective. That leaves a 2 on 2 scenario unless one or both of the 469 partners tries to dislodge the low geared high traction fan bot.

The fan bot is preferably a “wide drive” and parked wide side against the tower. Bid side against 469 presents less of a moment arm opportunity for 469 partners to push a distant fan bot corner corner and dislodge the fan bot. The wide drive scheme presents transverse wheel friction to minimize probability of being moved when pushed on its narrow end. Lastly, the ideal fan bot would drop high friction roughtop pads on the floor to make them really hard to move in any direction. Lastly the ideal fan bot would be able to swivel the fan turret slightly to tweak aim as the dislogers are working on pushing the fan bot around.

In qualifications however , it is probable that a lone fan bot will never meet 469 and thus never be tested against them.

Another countermeasures strategy specific to 469 is that with the correct timing of slamming into their back end, you can put significant movement on the top part of their tower exactly when the ball is seemingly stationary or near stationary for a moment. This would catapult the ball far enough towards the end zone so that the ball guides will be ineffective. Remember that they can have only 3 inches of ball penetration in their mechanism so even an inch of movement forward largely disenegages the guiding effect and 3 inches of movement has that ball in free fall without guides.

It was frustrating to watch one after the other of the one sided matches and not see 469’s opposition exploit this simple shaker scheme.

Drivers that are to face 469 could practice by watching the 469 videos while driving their bot in the pits against a dummy target. Figure out far far back you need to be with full throttle to make the hit at the exact correct time. Pick a station for the rolling ball on gantry to pass to give it full throttle.

An alternate shaker scheme just has you against the 469 bumper and punching the throttle to get the entire 469 gantry into resonance. Like trying to rock a van. Just repeatedly punch the throttle with some good eye hand coordination timing. Let it bounce you back and punch again. In 10 to 15 sec, you should master this just like you do when you rock van. .

A loop bot that grabs the tower higher up to stabilize their ramp will not be as susceptible to the shaker schemes.

Note that on many but not all balls, the ball appears stationary for a moment at the moment of catch on the 469 mechanism. Any rules on this? Videos were not closeups so not sure on this


469 came up with a novel and legislatively risky scheme and developed it. Hats of to them. I am glad that the concept (not the execution of it) did not get legislated out by a late rule change. 469 surely had many problems to solve to make this work right. I think the game may end up one sided in some venues but the FIRST community will be better for it. It demonstrates the real world possibility that your technical endeavor or business can come up against great odds and you need to rise to the challenge of countering it. Legislation and lawyers are one way in the real world to deal with this (Car racing, sailing, in business… ) but in FIRST I hope this drives more of a technical innovation route. You can invent around seemingly insurmountable obstacles.

Hmm perhaps intelligence to GDC of the existence of loop bots drove the increase of hold-back to 65 lbs. I had wondered why they did that at the late stage and perhaps this was the reason… so that teams could make countermeasures changes or do their own loop mechanism. Anyone think of a better reason for that late rule change. With 65 lbs, you can almost build a full robot.

Discussion/debate is invited.

Team Update #11 increased the Withholding Allowance to 65 lbs in response to the record snowstorms in the Mid-Atlantic Region. Many teams lost a week plus of build time near ship day as schools closed and states of emergency were declared.

Thanks for the clarification. I was not aware.

I suppose we can be thankful for the storms in triggering the additional hold-back mechanism.
This will surely allow more effective countermeasures against loop bots.

They can, and have, left the tunnel after deploying their mechanism.

All this apocalyptic talk of 469 and their ilk running rampant and destroying the competition is a little premature, don’t you think? We’ve only played two weeks and seen one of these bots dominate. Perhaps we should let the game evolve a bit, first? :rolleyes:

The 469 strategy is pretty effective, but it is beatable. I posted here: basically saying that they can’t do anything without soccer balls. The videos I saw were showing some pretty ineffective defending robots that could not clear the ball out of the zone.

There are some physical limitations to just how fast the trident can be used to feed the balls in. Also, a good coach will have the defense driver over there letting them know when balls are coming in. It does require a strong robot with a kicker.

The shaker strategy would have been an easy one to try at Cass Tech. It would be a good way to test out the robustness of their mechanism.

  • T

A loopy robot that grabs the tower higher is asking to be made into a pendulum. the worst loop bots will have multiple attachment points. Then you would have to match the resonance of the tower. <and risk field damage?>

Any tests on how tolerant the tower is to rosonant movement with a robot locked onto it?

Agreed that this will not destroy the competition and should not be seen as an apocalypse . Loop bots will hopefully be copied enough to make finals less of a one sided scenario. Effective countermeasures may be the deciding factor with multiple loop bots in a competition.

I am excited about 469’s development and feel that it will make the learning experience better by providing a few additional weeks of late stage tasks and excitement to the builders and designers to develop countermeasures within the hold-back rules and countermeasure strategies. More than anything, as Dean and Woodie keep on saying, “it is not about the bot or the game…”. It gives a more realistic glimpse of real life in the technology industry. I hope this excitement and challenge inspire more undecided students to enter the field.

My thread was started when many people were watching 469’s opponents drown on You-tube and in my opinion spending far more forum space describing the water than how the drowning alliance may save themselves.

This thread content was intended mostly to provide constructive light at the end of the tunnel for teams that are about to face this type of opposing alliance in Troy and Nationals. The glass is half full. Now fill it the rest of the way.

I hope some others contribute better ideas than mine and share them with the community. I would love to see a rookie team develop the most effective countermeasure.


That’s a rather unfair characterization. The lone defender bot also had to defend against balls rolling off 469, try to stop 217 from racing about cleaning up missed balls, while 2960 hassled the defender. A daunting task.

Both the robot director mechanism and tower move. Not at the same frequency. For resonance info , see the videos of 469. There are a couple high res videos and some really low res ones. I wish that the low res could be recoded by the person that posted them or more high res can be posted. With frame by frame playback, and knowledge of frame rate you can exactly work out the rate at which you need to deliver stimulus impulses (hits) to the bot. Getting tower into high enough amplitude resonance may be real difficult and need much more energetic impulses and risk field damage or disturbance penalty.

Smart loop bot design will isolate (not necessarily separate) the upper mechanism from the bumper section and make all of this shaker stuffharder to do.

Aloop bot grabbing high (as well as low) may get a bit of pendulum effect, but you don’t care if bottom of bot is swinging (undulating not hanging) a bit more than the top mechanism as long as the ball gets guided and loses contact higher up on the mechanism where it can be moved less by resonance inducing impulses.

Clever counter measures will install a hybrid mode for the shaking of the loop bot and have a pot at the DS to adjust the frequency of the impulses. This way it is not up to the driver skill to maintain periodicity and to get the initial frequency close. Get the starting period/frequency close by analyzing video and then in game play tweak the frequency while hitting the bot with the hybrid mode shaker. Similar to the tree shakers for dropping fruit and nuts where the operator can compensate the frequency for the stiffness of tree and mass of the branches.

Reconciled that they have 20 seconds to score at the end but you can keep them out of the game as long as possible with these schemes. If the shakers work, the loop bots will have meticulous coaching to hold back those last balls a bit if they have them available. They will risk penalties for that strategy.

Team 3135 came close to choosing a loop bot design at the brainstorming stage. We finally bailed on it because it seemed too risky with respect to the rules.
We had already completed a similar concept in FTC Chicago that caught 15 balls right out of the drop chute, and even caught the yellow ball later. Our shooter was just too weak and erratic though, so we only took second place.

With FRC, we could not clearly interpret whether a gravity powered ball re-director chute could be rotated for targeting to either goal (as 469’s flipper does), without violating the rules. So, 496’s stationary 2-way chute with a flipper to steer balls to either side works well - smart! Our team also felt that, beside risky, it was also in conflict with the “spirit” of the game, and so the idea got voted down.

Hats off to #469 for taking the risk and confirming the legality of this scheme - we were too timid to gamble. Meanwhile, the neutralizing concepts must be worked out. We did consider these thoroughly while we still entertained doing the looper scheme.
We had assumed that the bot’s re-directing chute would have to remain stationary while “shedding” a ball toward one goal or other. We assumed balls would be “INSIDE OUR PERIMETER” by more than 3" at this stage, so any moving mechanism touching the ball would give a penalty. After “shedding” a ball from our static chute toward one goal, I had assumed the rules allowed us to then re-point our chute, just** before** next ball arrived, toward whichever goal seemed least defendable. Since 469 never turns their ball chute once it’s positioned on the platform, they avoid the penalty of manipulating balls that are inside their perimeter. However, they do operate a flipper to route balls through either side of chute, as balls come down the 2-way chute. A moving mechanism while ball is above bot’s base should be a penalty, since ball IS WITHIN THE BOT’s (virtual) PERIMETER, which projects vertically up from base. Do they move the left-right flipper before ball drops onto bot, or after it starts sliding down the chute? Not clear from video?
Now as to defending this:

  1. Can a fast defender bot sit centered in their zone and intercept balls based on anticipating which way 469 points their ball flipper? I think so, but I can’t tell how long into their cycle they wait to commit as to which goal they are targeting? It seems to be VERY last second commit for diverting balls left or right on the chute. Plus, the defender must not only intercept balls, but also clear balls from their zone while two opponents are harassing them - not so easy!

  2. can a hump navigator bot go up on (or adjacent to) the climber platform , latch on to a pipe, and obstruct the flow of the balls coming through 469’s ball chute, or even poke it out of the air before it arrives on their their chute? Risky, as contacting 469 in any way could be a penalty. Perhaps a “wall bot” that’s wide enough to block their trajectory toward either side? Not so easy though, as they (wisely) chose to drop balls onto the hump to gain better horizontal shot velocity, which also gives them a harder-to-block, wider angle of chute discharge. ***WOOPS, NO EXPANSION AT OPPONENTS TOWER NIXES THIS!! FORGOT.

  3. My favorite idea at this stage it to “poke a stick” through their chute at the appropriate spot to stop ball flow through it. Perhaps even poke a stick right at spot where balls leave the return ramp. Can this be done so as to choke up all the returning balls in a queue on top of their ramp? Is it legal, as long as no contact with ramp is made? The max expanded height seems to allow this**.*WOOPS, NO EXPANSION AT OPPONENTS TOWER NIXES THIS!! FORGOT. If so, it would be poetic justice for them!
    -Dick Ledford - #3135 mentor

The mechanism is not moving when in contact with a ball. In one of the videos floating around they receive a penalty for actuating the mechanism too late and having it still moving when the ball hits it. A ThunderChicken (I believe it was Paul Copioli) mentioned that this resulted in push-ups for the drive coach.