Pneumatic cylinders

Competition Rules/Strategy
1

Can we use cylinders with bores different to those specified in the pneumatics manual?

2

No bores are specified in the game manual.
R84i allows “Pneumatic cylinders, pneumatic linear actuators, and rotary actuators,”
Have at it. :+1:
But do read R81 through R94 thoroughly, and do a “self inspection” against those rules before powering the compressor or charging a tank. Don’t skip the pneumatics rules, even during prototyping.

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3

Anything that meets the rules listed in 10.9.

Standout parts (not a comprehensive list):

  • Needs to be rated for 125 or 70 psi (depending on if it’s upstream or downstream of your 60 PSI max regulator)
  • Needs to be able to connect to your max 1/4" OD Pneumatics tubing, ideally using whatever fittings you currently have

Assuming the parts meet all the rules feel free to use that 24" stroke, 30" Diameter piston you’ve been dreaming about. Just make sure you take into account how much air one of these larger pistons will eat up with every stroke; Pneumatics are useless without air behind them.

4

I was talking about the pneumatics manual.

5

I’m not quite sure what document you’re referring to (I’ve seen several over the years), but what matters for passing inspection with pneumatics is R81 through R94 of the game manual (and the other rules in the game manual, of course). If you follow those rules in both letter and intent, you’re also doing it safely.:goggles:

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6

Oh, boy. Have fun fitting that inside the frame perimeter and initial configuration with the rest of the control system and enough tanks to fill it within the match. I guess if you only need a couple of psi in the cylinder (that’s 1400 lb, so maybe) you could do it.

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7

It’s only 40% of the robot’s total volume; there’s room for a second one. Who needs a “chassis” or “scoring systems”? Opponents will concede on sight of your raw pneumatic power.

Though with the volume of the air needing to go through 1/4" OD lines it might take half the match just to extend. But at 60 psi it could probably lift all of the drive teams at the event simultaneously, so that’s cool.

8

It would probably cost more than the per-item maximum cost limit though…

9

You still need enough drive train to get out of the HAB and back in because of that entry at the bottom middle of table 5-1: “A ROBOT that hasn’t fully crossed their HAB LINE to leave their HAB ZONE at any point during the MATCH isn’t eligible.” [for HAB CLIMB bonuses], unless you’re planning to expend all your energy getting two alliance partners up to seed high in qualifications for a function which will be worth much less (maybe nothing) in eliminations.

10

With the entire opposing alliance eyes wide and quaking in their boots at the very sight of the 30" diameter pistons they won’t be able to score a single point. With the Pneumatic Ultra-bot effectively running perfect defense against the entire alliance our teammates will have free reign of the field. No need to even move off the starting platform.

It’s a flawless strategy: we’d easily be able to win both World Championships, probably even the secret Galactic Championships. Although the teams actually on planet Primus have a huge home field advantage this year.

11

The internet is abuzz trying to purchase whatever it is you’re drinking/smoking.
(Please understand this as a joke!)

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12

largest non-custom air cylinder I can find has a 12 inch bore and 50 inch stroke with 2 inch diameter Rod, too big to fit inside the starting configuration, but you can get the same bore in shorter lengths :grin:

13

I’m drinking raw inspiration, and smoking a fat roll of coopertition. You can find a local supply at https://www.firstinspires.org/team-event-search#type=teams&sort=name&programs=FLLJR,FLL,FTC,FRC&year=2018

The comments posted in this thread are the sole beliefs and values of myself and do not reflect the values or beliefs of team 4682, it’s host school, or any other affiliated organization.

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14

Hmm. pneumatic cylinders aren’t specifically required to be COTS, just rated by their manufacturers for 70psi and unaltered, but they do have to cost less than $500 each.

Edit: Read the bullets under R82 but not the body…

15

I know, but when its week three of build and your strategy takes a sharp turn to this much superior option, you need parts FAST, so its easier if its cots :rofl:

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16

SO what you’re saying is to manufacture my own and say its rated for 70psi right?

17

You all laugh, but I have seen a robot with not one, but two ~18"x4" cylinders with a 1" diameter rod. To be fair they had done some calculations on how much air it was going to take to use, I think they had ~30 air tanks. Of course I don’t think they had considered the 1.1cfm of the compressor.

I believe the initial robot weight was ~150lbs.

18

Calling your bluff, R82. That whole “all pneumatic items must be COTS pneumatic devices” kind of kills the vibe. @T3_1565 in case you missed that.

19

Well my whole game plan is ruined…

20

Assuming you are talking about the pneumatics manual in the mechanical resource library on the first web site… The last revision was apparently 2017. While useful as a resource, it is out of date and not part of the rules. For example is has a diagram of an off-board compressor which is not legal this year.