Max Number of Cylinders?

Technical Pneumatics
1

Is there a rule that states if there is a maximum number of cylinders that can be used on a robot? Thanks!
Stephanie

2

I do not believe that there is a limit on cylinders<R72-D>, only on storage tanks(limit 4)

3

Legally, no.

Practically, yes. There’s a limit to how quickly the compressor can charge the tanks…

4

By rule, you can only use 4 storage tanks.
By rule, there is no limit to the number of actuators (cylinders) you may use … however, you do have a finite amount of compressed air (both stored and generated) and a finite number of valves you can control (limited by the cRIO)

5

Thanks for the help!
Stephanie

6

2 years ago we had 9. Most we ever had.

7

The max is a 120lbs worth.

8

Actually, depending on the app, valves may NOT be as limited as one might think. First off, you can use both the Solenoid drivers AND Spikes to control valves. Secondly, <R49> DOES allow you to control multiple (12V) valves from a single Spike. Therefore, if for example you are connecting valves in parallel to increase “effective flow”, you can add quite a few to the system!

I agree though you do have limited WORK the entire pneumatics system can perform. Your maximum work is related to 4 Clippard Tanks worth of pre-round stored air, plus whatever you can pump during the round with the sole provided Thomas kit compressor. That isn’t very much work at all. It places a practical limit of what you can DO with air, regardless of the number of cylinders you have. For example, you can’t use it for a drive train to make a robot that chugs around on air like a steam engine…:smiley: You don’t have the air for it for it to travel very far.

HOWEVER, you CAN gear shift, grip, deploy, and TRIGGER devices (like spring driven things) an awful LOT with little cylinders. You can also reserve your air for a few MAJOR acts (like a lift or a transformer-bot deploy), with large cylinders.

You can also make a Doomsday Device, that operates when the round clock goes to zero, to try to quickly protect your score (like actuate brakes on your robot), or maximize it “before the field settles” (like release the gripper so you aren’t touching an object anymore). In this game, you may wish your shooter to fire off once last time as the clock expires. It MAY give you one last point! ( It also has the side benefit of releasing any stored energy before the students approach it, which could be considered a safety feature… :smiley: )

Some of Keith’s Rules of Thumb wrt Pneumatics:

  • Adding the Pneumatics compressor/system is costly in weight, so if you ARE going to use cylinders, Use Them A LOT. (IOW, find a LOT of little things they can do for you, or something ONLY pneumatics can do for you, like provide force while stalled.)
  • If you are only doing a TINY amount of work (like gear shifting, or a one time device trigger, like a deploy or bin release), consider a compressor-less system to save weight, and run it on tanked air.
  • If you only have a single or few things to do, but they are BIG in work load, you may wish to consider Winches as a motor-based alternative to pneumatics, to save the weight of the compressor and its related parts.
  • If you are NEARLY out of air because you have a lot of pneumatics devices, consider replacing one or more of the biggest air hogs with winches, to save the air for things only pneumatics can do.

Bottom line - Cylinder Count isn’t nearly as important as Proper Air Management. Use your limited air WISELY.

  • Keith