Hi I’m from team 4191Z I just have a question on pneumatics. How much do you pump it up. What are the pieces called. Is there anything not to do. This is our first time with pneumatics.
Never used them before but I know from others that you should not use them for lifts as they are very weak.
Well, all of the parts are rated at 100 psi, so i don’t suggest going over that. As for things you shouldn’t do, don’t use plumber’s tape and absolutely never ever should you for any reason even think about purchasing pnuematics from the vex store unless you need the valves (obviously i am exagerating a bit but it is true. If you need to buy individual parts, find another vendor near you.) All of the pnuematics parts are manufactured by SMC which is all sold at other places for MUCH less money. Hope this helped. Let me know if you have any questions!
I think that statement should be taken back. It entirely depends how you use the pneumatics in general. Pretty sure our pneumatic lift will change some of your guys’ mind when it comes to pneumatics being worth of lifts or not.
Its all about how you use them and what your final resources look like.
- Andrew
You could make just about anything a strong lift with enough rubber bands
On a side note I need to start getting my pneumatics setup for my next robot…
I completely agree. Granted, it is quite an undertaking to design and build a pneumatic lift. However, if you plan out your design and build it well, it could be very effective. It all depends on how well you plan the build out and how much time end effort(Math, lol) you put into to tweaking/modifying it to work flawlessly.
Hello, other Hoosier teams…
There are several threads regarding pneumatics use, mainly this one, especially for Sack Attack.
Some things regarding hooking up the pneumatics, this picture has helped.
Finally, in regards to programming your solenoid: if you are using easyC, see this thread. If you are using ROBOTC, you can use:
SensorValue[solenoid] = 1; // or 0
I think that’s it as far as basic pneumatics use goes…
I would also like to point out there is no limit on pneumatics thus far. Not using them is simply throwing away extra motion or abilities the robot could do.
-Andrew
The solenoids are rated for 100psi, the generally accepted maximum pressure for the VEX pneumatics system.
However, the tanks are rated for 200psi and the pressure regulators are rated for 160psi (this is from memory, so these numbers may not be exact).
Armed with this knowledge, you could make a convincing argument to the head ref that you can charge your tanks to 160psi as long as the output from the pressure regulator is under 100psi.
Karthik has said that this is not legal, but if you argued this at the tournament I was head ref-ing, I would let you get away with it; if your team can put together a legitimate argument based on actual numbers, then competently argue with the head ref about it, you deserve to win the argument. (I’m a bit of a rebel ref, I guess)
Just what I have heard on other threads. I am always willing to accept other perspectives and ideas.
I agree. I think one of the Lynfield teams (2915C?) made an effective pneumatic lift for Sack Attack.
I found the pressure regulator part number. The actual part number is ARJ-1020F (for future viewers). The part number is located on the pressure regulator (you have to look for it, but I promise it’s on there). They are rated for a maximum operating pressure of 116 PSI (or 0.8 MPa) and a proof pressure of 174 psi (or 1.2 MPa). The documentation is here. If you click on the link, be sure be sure to scroll down to the correct section.
It doesn’t really matter what we think the system can handle. It matters what the rules say. Isn’t that a ref’s job?
That would be okay if the rules stated “Pistons cannot be get more than 100 psi from their air tanks.” The rules do state.
https://vexforum.com/t/answered-maximum-pressure-of-pneumatic-tanks/17690/1
If there was a way to upvote, spotlight, favorite, or like a post, I would do so to this one.
Very well put, snowpenguin.
Thanks for the clarification! I forget where the 160 came from…but regardless of the details, I stand by what I said.
From my point of view as a student, the rules were there to make sure no one got an unfair advantage and to keep the game safe. And as a ref, I tried to maintain that perspective when interpreting rules. In the specific case of pneumatics:
Everywhere I’ve seen that says 100psi is the max pressure for the system also says that it’s for safety reasons (as opposed to keeping things fair), so taking into account the ‘common sense’ rule, if someone can prove that it’s safe to go higher, that 100psi rule becomes invalid. However, it would be very difficult to do so (providing documentation for every single part, etc.)
More generally:
I don’t disqualify or punish teams for not having a backup battery, for having a robot that is 18.5" at the start of a match (after passing inspection), for using 1/8" polycarb if it doesn’t provide a significant advantage, for stepping outside of their driver station, for not wearing safety glasses at the fields, for adjusting their robot after the red team has placed their robots, for cutting holes in their joysticks to allow for an external battery pack, etc.
Does that make me a bad ref? I would say that I am being a reasonable rule-enforcer, who is trying to help the teams to have a fun and fair competition (in the spirit of the program).
I’ve been to too many competitions (as a student) where the head ref doesn’t know the rules or decides to change the rules because (and I quote) it’s “the ref’s event, not the students’, and the students have no right to question the ref.” I think most students would rather see an event run in a fun and helpful manner, rather than an event where you aren’t allowed to test your robot in competition because your backup battery is dead.
I can get behind that philosophy. But once again we don’t get to choose not to follow the rules because “we think the reason behind them is safety not fairness”. We don’t get to choose not to follow them under any circumstances. They are the rules, and though you may think you’re being fair, you’re really giving anyone using pneumatics at your events an unfair advantage over others at the event and others at other events. You can’t simply use the “common sense” rule to justify breaking another rule.