Go to Post Possibly the most amazing thing all week was that this game can be played with mecanum wheels. - fargus111111111 [more]
Home
Go Back   Chief Delphi > Technical > Technical Discussion
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 31-03-2002, 17:57
geo's Avatar
geo geo is offline
A Nuke Would Do The Job!
FRC #0865 (WARP 7)
Team Role: Alumni
 
Join Date: Jan 2002
Rookie Year: 2002
Location: Toronto,ON,Canada
Posts: 276
geo is a jewel in the roughgeo is a jewel in the roughgeo is a jewel in the roughgeo is a jewel in the rough
Lightbulb I am wondering...........

Is it necessary to put two pressure switch on the pneumatics system or just one?
  #2   Spotlight this post!  
Unread 31-03-2002, 18:47
Jay Lundy Jay Lundy is offline
Programmer/Driver 2001-2004
FRC #0254 (The Cheesy Poofs)
Team Role: Alumni
 
Join Date: Jun 2001
Rookie Year: 2001
Location: Berkeley, CA
Posts: 320
Jay Lundy is a name known to allJay Lundy is a name known to allJay Lundy is a name known to allJay Lundy is a name known to allJay Lundy is a name known to allJay Lundy is a name known to all
One is enough.
  #3   Spotlight this post!  
Unread 31-03-2002, 19:18
RebAl's Avatar
RebAl RebAl is offline
ISee It When I Believe It
None #0329 (The R.A.I.D.)
Team Role: Mentor
 
Join Date: Jan 2002
Rookie Year: 2001
Location: N.Y.
Posts: 215
RebAl will become famous soon enough
Send a message via ICQ to RebAl Send a message via AIM to RebAl
But 2 is necessary to have a efficent system, one set to system low and another set to system high, this will prevent unecessary cycling of the pump, and save some breakers
  #4   Spotlight this post!  
Unread 10-04-2002, 13:58
AdamT's Avatar
AdamT AdamT is offline
.
#0401
 
Join Date: Jan 2002
Rookie Year: 2000
Location: not Blacksburg, Virginia
Posts: 836
AdamT is on a distinguished road
You can and according to the manual, you should put two on...one for each accumulator. You run it so that the 115 psi switch is on the first accumulator on the line, and 110 on the second. You then program it so that when it sets off the 115 psi switch, the pump turns off, then when the 110 psi switch is released, the pump starts back up...

I would also pre-pressurize the tanks before matches.
__________________
~Adam

  #5   Spotlight this post!  
Unread 10-04-2002, 14:44
Joe Johnson's Avatar Unsung FIRST Hero
Joe Johnson Joe Johnson is offline
Engineer at Medrobotics
AKA: Dr. Joe
FRC #0088 (TJ2)
Team Role: Engineer
 
Join Date: May 2001
Rookie Year: 1996
Location: Raynham, MA
Posts: 2,648
Joe Johnson has a reputation beyond reputeJoe Johnson has a reputation beyond reputeJoe Johnson has a reputation beyond reputeJoe Johnson has a reputation beyond reputeJoe Johnson has a reputation beyond reputeJoe Johnson has a reputation beyond reputeJoe Johnson has a reputation beyond reputeJoe Johnson has a reputation beyond reputeJoe Johnson has a reputation beyond reputeJoe Johnson has a reputation beyond reputeJoe Johnson has a reputation beyond repute
1 switch + delayed turn off code

I don't thinks the switch is required. Also, you don't necessarily need to have 2 switches to have an efficient system.

It is possible to write code that runs the pump for XXX seconds after the switch is made. We set the switch to 100 psi or so. Then we measure how long it takes the pump to get to 120 psi after the switch makes its transition to indicate the pressure is above 100 psi. We then use the delayed turn off code to keep the pump running until the pressure is at 120 psi.

Joe J.
  #6   Spotlight this post!  
Unread 10-04-2002, 14:45
Lloyd Burns Lloyd Burns is offline
Registered User
FRC #1246 (Agincourt Robotics)
Team Role: Engineer
 
Join Date: Jun 2001
Rookie Year: 1997
Location: Toronto
Posts: 292
Lloyd Burns is an unknown quantity at this point
One of the top robots at the Canadian Regional (who only received ONE switch) have the switch show the operator (via the SW1 LED on the OI) when the pressure is low, and then he holds a button down until the light goes out.

I had shown them the code for counting time that we used last year, but they simplified it some :-) .

"Uncomplicated may win !" parlayed the paraphrased playful Pappalardo Professor.
  #7   Spotlight this post!  
Unread 10-04-2002, 14:57
AdamT's Avatar
AdamT AdamT is offline
.
#0401
 
Join Date: Jan 2002
Rookie Year: 2000
Location: not Blacksburg, Virginia
Posts: 836
AdamT is on a distinguished road
I dunno, our method didn't seem too complecated to me, and there's no guesstimating and operator involvement....i like those ideas though.
__________________
~Adam

  #8   Spotlight this post!  
Unread 12-04-2002, 17:54
The Lucas's Avatar
The Lucas The Lucas is offline
CaMOElot, it is a silly place
AKA: My First Name is really "The" (or Brian)
FRC #0365 (The Miracle Workerz); FRC#1495 (AGR); FRC#4342 (Demon)
Team Role: Mentor
 
Join Date: Mar 2002
Rookie Year: 2001
Location: Dela-Where?
Posts: 1,564
The Lucas has a reputation beyond reputeThe Lucas has a reputation beyond reputeThe Lucas has a reputation beyond reputeThe Lucas has a reputation beyond reputeThe Lucas has a reputation beyond reputeThe Lucas has a reputation beyond reputeThe Lucas has a reputation beyond reputeThe Lucas has a reputation beyond reputeThe Lucas has a reputation beyond reputeThe Lucas has a reputation beyond reputeThe Lucas has a reputation beyond repute
Send a message via AIM to The Lucas
One Switch Debounce

You could set the one switch to 120 psi. Then use the program to debounce the pressure switch. When the switch first indicates that the pressure is at 120 or above, use a counter variable to wait 1 sec (roughly 40 cycles of the main loop) before turning the pump off. Use the same delay before turning on the pump after the pessure drops below 120.
__________________
Electrical & Programming Mentor ---Team #365 "The Miracle Workerz"
Programming Mentor ---Team #4342 "Demon Robotics"
Founding Mentor --- Team #1495 Avon Grove High School
2007 CMP Chairman's Award - Thanks to all MOE members (and others) past and present who made it a reality.
Robot Inspector
"I don't think I'm ever more ''aware'' than I am right after I burn my thumb with a soldering iron"
  #9   Spotlight this post!  
Unread 15-04-2002, 08:48
Jim Meyer's Avatar
Jim Meyer Jim Meyer is offline
Engineering Mentor
None #0067 (HOT)
Team Role: Engineer
 
Join Date: Jun 2001
Rookie Year: 2000
Location: Milford Michigan
Posts: 177
Jim Meyer has a reputation beyond reputeJim Meyer has a reputation beyond reputeJim Meyer has a reputation beyond reputeJim Meyer has a reputation beyond reputeJim Meyer has a reputation beyond reputeJim Meyer has a reputation beyond reputeJim Meyer has a reputation beyond reputeJim Meyer has a reputation beyond reputeJim Meyer has a reputation beyond reputeJim Meyer has a reputation beyond reputeJim Meyer has a reputation beyond repute
Two Switches Makes it Easy....

The benefit of having two switches is ease of programming. With them both connected to the accumulators, if you set one at 120 psi and the other at 100 psi you can program the compressor to turn on when the pressure dropps below 100 and shut off when the pressure gets to 120 psi. This way you don't have to do any "debouncing".

Last year we had problems blowing fuses on the spikes if we turned the compressor on with an accumulator pressure at 120 psi. It didn't happen very often but I believe it is good practice to not turn your compressor on unless the accumulator pressure is less than 100 psi. The easiest way to do this is with two switches. The method Joe J. mentions is also a good one but is probbably a little trickier to program. The method described by "The Lucas" allows the compressor to turn on at high pressures if you have a slow leak or a small cylinder.

Last edited by Jim Meyer : 15-04-2002 at 08:56.
  #10   Spotlight this post!  
Unread 15-04-2002, 11:18
asher asher is offline
Registered User
None #0031
 
Join Date: May 2001
Rookie Year: 2000
Location: Oklahoma
Posts: 193
asher will become famous soon enough
the less our driver has to think the better, 2 switches is what we feel is best, no thinking required.
  #11   Spotlight this post!  
Unread 15-04-2002, 13:17
Unsung FIRST Hero
Ed Sparks Ed Sparks is offline
Engineer/Mentor/Inspector
AKA: FirstCadLibrary Guy, Inspector Dude
FRC #3959 (Formally with FRC-34)
Team Role: Engineer
 
Join Date: Jul 2001
Rookie Year: 1996
Location: Huntsville, Alabama
Posts: 624
Ed Sparks has a reputation beyond reputeEd Sparks has a reputation beyond reputeEd Sparks has a reputation beyond reputeEd Sparks has a reputation beyond reputeEd Sparks has a reputation beyond reputeEd Sparks has a reputation beyond reputeEd Sparks has a reputation beyond reputeEd Sparks has a reputation beyond reputeEd Sparks has a reputation beyond reputeEd Sparks has a reputation beyond reputeEd Sparks has a reputation beyond repute
Send a message via AIM to Ed Sparks Send a message via Yahoo to Ed Sparks
Exclamation One is good enough ....

We use the one switch + delay that Joe mentioned. It works fine, less parts, one less input, and the code is easy enough.

Prior to this year, we only had the one switch to work with. It's one of those "It ain't broke - don't fix it" things for us.

__________________
Ed Sparks

MECH TECH FRC-3959
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
just wondering..(sensors) JasonStern Electrical 14 08-05-2003 00:16
just wondering robomama Chit-Chat 26 23-07-2002 23:44
ANTI-MATTER, i was wondering... archiver 2001 2 24-06-2002 01:15
I was just wondering about FIRSTanimators and Chiefdelphi Robby O CD Forum Support 2 25-01-2002 00:19
I am wondering what kind of jobs the adults have... Ken Leung Career 15 23-07-2001 15:19


All times are GMT -5. The time now is 00:41.

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