Go to Post "The lowly snowflake is very fragile, but look at what they can do when they stick together" - Wayne Doenges [more]
Home
Go Back   Chief Delphi > Technical > Pneumatics
CD-Media   CD-Spy  
portal register members calendar search Today's Posts Mark Forums Read FAQ rules

 
Closed Thread
Thread Tools Rate Thread Display Modes
  #1   Spotlight this post!  
Unread 12-02-2010, 00:32
The Ars-sassin The Ars-sassin is offline
Registered User
AKA: The Ars-sassin
FRC #2443 (N/A)
Team Role: Engineer
 
Join Date: Jan 2009
Rookie Year: 2007
Location: Maui, HI
Posts: 11
The Ars-sassin is an unknown quantity at this point
Piston Question

Does anyone know if it's allowed for our robot run an input/output pneumatic piston with only ONE hose on the piston (e.g-a piston with only an input hose or an output hose; the other would just be open).
  #2   Spotlight this post!  
Unread 12-02-2010, 00:35
EricH's Avatar
EricH EricH is offline
New year, new team
FRC #1197 (Torbots)
Team Role: Engineer
 
Join Date: Jan 2005
Rookie Year: 2003
Location: SoCal
Posts: 19,825
EricH has a reputation beyond reputeEricH has a reputation beyond reputeEricH has a reputation beyond reputeEricH has a reputation beyond reputeEricH has a reputation beyond reputeEricH has a reputation beyond reputeEricH has a reputation beyond reputeEricH has a reputation beyond reputeEricH has a reputation beyond reputeEricH has a reputation beyond reputeEricH has a reputation beyond repute
Re: Piston Question

Why would you want to do that?

The rules don't specify that each piston has to have both ends connected, but I don't see a reason to have a 1-way piston, other than that something else would be pulling it back or it's a 1-shot application.
__________________
Past teams:
2003-2007: FRC0330 BeachBots
2008: FRC1135 Shmoebotics
2012: FRC4046 Schroedinger's Dragons

"Rockets are tricky..."--Elon Musk

  #3   Spotlight this post!  
Unread 12-02-2010, 00:36
EthanMiller EthanMiller is offline
Lead Programmer
AKA: Socks
FTC #4356 (The Zip Ties)
Team Role: Programmer
 
Join Date: Jan 2010
Rookie Year: 2009
Location: Clayton, NY
Posts: 121
EthanMiller has a spectacular aura aboutEthanMiller has a spectacular aura aboutEthanMiller has a spectacular aura about
Re: Piston Question

My team tried that, but it seemed air escaped, although for the life of me I don't know why. This is second hand, though. Feel free to pull out a hose and try it - it won't break anything.

As long as you unplug the hose when there's no pressure.
__________________
When all else fails, read the manual.

FRC 1713 K Island Gears 2009, 2010 (Not 2011 due to budget, hopefully 2012!) - Fingerlakes Regional

FTC 4356 The Zip Ties 2010-2011 Season - NNYRC (2010 9th seed).
  #4   Spotlight this post!  
Unread 12-02-2010, 00:50
Vikesrock's Avatar
Vikesrock Vikesrock is offline
Team 2175 Founder
AKA: Kevin O'Connor
no team
Team Role: Engineer
 
Join Date: Mar 2006
Rookie Year: 2007
Location: Manchester, NH
Posts: 3,305
Vikesrock has a reputation beyond reputeVikesrock has a reputation beyond reputeVikesrock has a reputation beyond reputeVikesrock has a reputation beyond reputeVikesrock has a reputation beyond reputeVikesrock has a reputation beyond reputeVikesrock has a reputation beyond reputeVikesrock has a reputation beyond reputeVikesrock has a reputation beyond reputeVikesrock has a reputation beyond reputeVikesrock has a reputation beyond repute
Send a message via AIM to Vikesrock Send a message via MSN to Vikesrock Send a message via Yahoo to Vikesrock
Re: Piston Question

Quote:
Originally Posted by EthanMiller View Post
My team tried that, but it seemed air escaped, although for the life of me I don't know why. This is second hand, though. Feel free to pull out a hose and try it - it won't break anything.

As long as you unplug the hose when there's no pressure.
You will hear air coming out of the open port when the piston moves towards the open port and entering the port when the piston moves away from it.

If air is actually constantly leaking out of the open piston port I believe that the piston is broken as that sounds like a bad internal seal.

Regarding the original question, this is perfectly legal:
http://forums.usfirst.org/showthread.php?t=14218

Eric, it is often desirable to simply vent one port of a cylinder if it will already be returned by other means in order to save air. Our 2008 robot vented the retract port of our arm raising cylinder through a flow control valve and let gravity bring it down.
__________________


2007 Wisconsin Regional Highest Rookie Seed & Regional Finalists (Thanks 930 & 2039)
2008 MN Regional Semifinalists (Thanks 2472 & 1756)
2009 Northstar Regional Semifinalists (Thanks 171 & 525)
  #5   Spotlight this post!  
Unread 12-02-2010, 01:05
IndySam's Avatar
IndySam IndySam is online now
Registered User
FRC #0829 (Digital Goats)
Team Role: Mentor
 
Join Date: Nov 2005
Rookie Year: 2004
Location: Indy
Posts: 3,362
IndySam has a reputation beyond reputeIndySam has a reputation beyond reputeIndySam has a reputation beyond reputeIndySam has a reputation beyond reputeIndySam has a reputation beyond reputeIndySam has a reputation beyond reputeIndySam has a reputation beyond reputeIndySam has a reputation beyond reputeIndySam has a reputation beyond reputeIndySam has a reputation beyond reputeIndySam has a reputation beyond repute
Re: Piston Question

It is perfectly fine to run a cylinder this way and I will wager you will see a lot of it this year.
__________________
"Champions are champions not because they do anything extraordinary but because they do the ordinary things better than anyone else." —Chuck Knoll


2015 Indianapolis District Winner
2014 Boilermaker Regional Industrial Design Award
2013 Smoky Mountain Regional Industrial Design Award
2012 Boilermaker Engineering Excellence Award
2010 Boilermaker Rockwell Innovation in Control Award.
2009 Buckeye J&J Gracious Professionalism Award
2009 Boilermaker J&J Gracious Professionalism Award
2008 Boilermaker J&J Gracious Professionalism Award
2007 St Louis Regional Winners
  #6   Spotlight this post!  
Unread 12-02-2010, 09:49
Ether's Avatar
Ether Ether is offline
systems engineer (retired)
no team
 
Join Date: Nov 2009
Rookie Year: 1969
Location: US
Posts: 8,125
Ether has a reputation beyond reputeEther has a reputation beyond reputeEther has a reputation beyond reputeEther has a reputation beyond reputeEther has a reputation beyond reputeEther has a reputation beyond reputeEther has a reputation beyond reputeEther has a reputation beyond reputeEther has a reputation beyond reputeEther has a reputation beyond reputeEther has a reputation beyond repute
Re: Piston Question

Quote:
Originally Posted by EricH View Post
Why would you want to do that?

Because a pre-charged piston moves MUCH faster if it doesn't have to push a lot of air through a small exhaust hole.

You can make an impressive kicker this way.

http://www.chiefdelphi.com/forums/showpost.php?p=910176


~
Closed Thread


Thread Tools
Display Modes Rate This Thread
Rate This Thread:

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

vB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Forum Jump

Similar Threads
Thread Thread Starter Forum Replies Last Post
Question about partial piston stroke itsme Pneumatics 10 30-01-2008 15:29
spring piston Matt21q General Forum 2 02-02-2007 23:44
spring piston? Matt21q Technical Discussion 2 02-02-2007 17:02
Piston question Spiffizzle Pneumatics 3 10-01-2007 21:17
Piston throw Alex N. Pneumatics 2 21-01-2004 21:19


All times are GMT -5. The time now is 22:27.

The Chief Delphi Forums are sponsored by Innovation First International, Inc.


Powered by vBulletin® Version 3.6.4
Copyright ©2000 - 2017, Jelsoft Enterprises Ltd.
Copyright © Chief Delphi