This year has been an interesting year for scaling mechanisms as teams try to meet some very difficult design constraints. With many teams deciding to go under the low bar, the packaging problem that comes with a scaling mechanism can get very challenging. I wanted to create a thread to talk about all of the awesome “out of the box” ways that teams have solved this problem.
Obviously what comes to mind is 118’s grappling hook - as far as I know we’ve never seen anything like that before.
But for my contribution I want to spotlight SWAG 4060:
Their scaling mechanism is a long inflatable tube with a hook at the end! It doesn’t even look like they can scale until the last 20 seconds, when a giant tube unfurls out of their robot and attaches to the rung. Their hanger got them all the way to the finals at Auburn, but sadly they didn’t get enough points to get to PNW Champs.
As a low bot…ours was super compact, pretty climb and very fast when it worked and went all the way to top once too far.
Simple scissor with slots in top part instead of holes so top could center and pop off to winch up.
We used a winch connected to “collapsible coat hanger” part of the scissor and 2 Cims.
Had a wood box centering it.
Successful QF scale in SD week 1 at end of clip.
We were alliance 8 they were alliance 1
One of our original designs was something either inflatable as in OP or with a spring like a snake, we spent lots of time initially looking a different options. Glad inflatable worked that is cool. Love its simplicity.
How does 4060 ensure that as the balloon thing collapses when lifting up, that it stays within the 15" extension zone?
It doesn’t look like it sticks too far out in the video but also seems like it could potentially end farther out.
I’m sure they thought this through so I’m just curious as to how they’re solving that issue. I would think some strong attached to the middle with a spring or something could guide it to collapse back into the robot.
We had an idea like that but decided that it would have failed inspection under R77 and as clarified by Q688.
I don’t know how 4060 did this, but we were considering a coiled wire or tube inside the inflatable that kept things from getting too far out of hand. Our first iteration would have been with a piece of lightweight dryer vent tube.
Link to a match where both us (226) and 217 scaled. We have a multi-stage lift made using rev-rail, and is connected to a series of constant load springs. The bottom of the mechanism is attached to a winch. At the end of the match the driver reverses the winch, allowing for the mechanism to go up, and then brings it down to scale. We used 2 cims for the scaler, and a back drive gearbox with a servo. I’m not sure about 217’s scaler, but I think it uses similar tactics with a lock to firmly grip the rung.
I was told while spectating 4060 at Auburn on Saturday that they fill the tube using a fan, separating it from the pneumatic system. I believe they 3D printed many of the components.
It looks like that homebrew compressor was pushing a whole lot more than 1.1 cfm. If you’re doing work with air, it’s a pneumatic device. (Noted exception for closed cycle air springs.)
If this is true, then all fans and fan-blown vacuum devices on FRC robots are illegal.
It is unclear to me what constitutes a pneumatic device. Obviously nothing custom can be connected to the “canonical” pneumatic system on the robot, which is heavily regulated.
EDIT: Vacuums are legal per R77. Other things maybe not.
R79 Compressed air on the ROBOT must be provided by one and only one compressor. Compressor
specifications must not exceed nominal 1.10 cfm flow rate @ 12VDC.
Hard to argue that an inflatable tube hanger does not create compressed air.
so how does a 3d printed fan fill a cheapo innertube to extend…?
could this be the work of a secondary compressor? (it may very well be the same work of the one original with a solenoid allowing for a tank to empty into it… or something…
also, i dont know that its the most consistent way to hook onto the bar, seeing as it wobbles here and there when they do it…
(again, please let me know if i have the wrong thought train here…)
Our scaling mechanism proved to be effective.
One or two issues with hook delivery. Our hook got bounced out of holder due to bouncing around by we solved that
Rule R79:
“Compressed air on the ROBOT must be provided by one and only one compressor. Compressor specifications must not exceed nominal 1.10 cfm flow rate @ 12VDC.”
this has already been pointed out…
also, a custom fan blowing a tube up (like a balloon) would be, in any circumstance, a compressor, thereby violating this rule. ergo, the custom fan has got to go if it is actuating something like it is.
We decided to use stored energy so that it would continue to climb once released. Also no chance of back driving. It is very fast.
We built a device that used a trailer winch to pre load shocks before matches.
2386 nearly went with using gas shocks too. They have the advantage of still pulling the robot up even once the buzzer goes. Effectively giving you another 5 seconds to the match.
“A ROBOT has SCALED the TOWER if,** at the conclusion of the MATCH**, the ROBOT:
A. is in contact with a unique RUNG, and
B. has all of its BUMPERS fully above the height of the low GOALS.”
The final assessment of ROBOTS having SCALED or CHALLENGED the TOWER is made five (5) seconds
after the ARENA timer displays zero (0), or when all ROBOTS have come to rest following the conclusion
of the MATCH, whichever happens first.
