Go to Post As long as the competition gets the attention of someone and drags them in, it doesn't matter how they get there. - Andy Grady [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
  #16   Spotlight this post!  
Unread 28-02-2004, 20:05
ngreen ngreen is online now
Registered User
AKA: Nelson Green
FRC #1108 (Panther Robotics)
Team Role: Mentor
 
Join Date: Jan 2003
Rookie Year: 2002
Location: Paola, KS
Posts: 821
ngreen has a brilliant futurengreen has a brilliant futurengreen has a brilliant futurengreen has a brilliant futurengreen has a brilliant futurengreen has a brilliant futurengreen has a brilliant futurengreen has a brilliant futurengreen has a brilliant futurengreen has a brilliant futurengreen has a brilliant future
Re: "hydraulics"

A full air tank and a couple solenoids and some tubing make a nasty dual spit wad shooter. It when through plastic and leather and lodged itself in the wood. I've be looking at those team with 7-8 solenoids on a single base and thinking cool. You could shoot like 8 spit wad a once and then shoot 8 more singles seperately or all together. Now I need to figure out how to reload. I bet you could lodge a spit wad in a speed controller. If it is lodged in another robot it is still on a robot.
  #17   Spotlight this post!  
Unread 28-02-2004, 22:07
steven114 steven114 is offline
Programming Wizard and Team Captain
AKA: Steven Schlansker
FRC #0114 (Eaglestrike)
Team Role: Programmer
 
Join Date: Feb 2004
Location: Los Altos, CA
Posts: 335
steven114 is a jewel in the roughsteven114 is a jewel in the roughsteven114 is a jewel in the rough
Send a message via AIM to steven114
Re: "hydraulics"

We made a tennis ball launcher out of the pneumatics - it was fun

We then continued to use it; we were launching soda bottles into the recycling bins...
  #18   Spotlight this post!  
Unread 11-04-2004, 00:47
kmcclary's Avatar
kmcclary kmcclary is offline
Founder 830/1015;Mentor 66/470/1502
FRC #0470 (Alpha Omega Robotics)
Team Role: Engineer
 
Join Date: Aug 2001
Rookie Year: 1994
Location: Ann Arbor, MI
Posts: 491
kmcclary has a reputation beyond reputekmcclary has a reputation beyond reputekmcclary has a reputation beyond reputekmcclary has a reputation beyond reputekmcclary has a reputation beyond reputekmcclary has a reputation beyond reputekmcclary has a reputation beyond reputekmcclary has a reputation beyond reputekmcclary has a reputation beyond reputekmcclary has a reputation beyond reputekmcclary has a reputation beyond repute
Re: "hydraulics"

Quote:
Originally Posted by IndyStef
BIG difference!
Air is compressible, hydraulic fluids are not (usually oil, rarely water)! That means that pneumatic systems can store energy relatively easily in a tank, but are not very accurately positionable under changing loads. Hydraulic systems are a lot heavier, and all energy has to be provided by the pump at the time when its needed (unless a pneumatic tank stores energy - in which case you could use pneumatics right away).
Yes, the most cited air/hydro differences are: compressibility (vs non), and a MUCH higher average working pressure in hydraulic systems.

But it is not true that a hydraulic system HAS to be limited by the pump's output. There are devices commonly known as "hydraulic accumulators" or "hydraulic surge suppressors". (You can web search on them.) These devices DO accumulate energy for hydraulic systems in the same way that the air tanks accumulate energy for pneumatic systems.

The main parts of a hydraulic accumulator are an expandable chamber for the fluid, working against a "spring force" of some kind. This is often implemented as a very high pressure vessel with a flexible diaphragm of some kind bisecting it and air on the other side to act as the spring, or as a hydraulic piston with a VERY heavy duty spring, air, or displaced vertical weight giving the back force.

For example: Smart multi-car hydraulic "elevator array" systems in buildings can use the unused elevator cars as "accumulators". They SWAP energy for "nearly free rides" with valves by sending one or more empty cars one way as the full one goes the other, or transferring the surplus "down" energy into a BIG standard accumulator to be reclaimed later for "up" use. Down can ALWAYS be had at any time by simply opening a valve. A Smart Array system (hydraulic OR electric based) can save the building owners a LOT in energy costs over the long haul.

Anyway... Standard compact hydraulic accumulators are NORMALLY used for one of these reasons (there may be others, but these are the most common):
A) To store energy for high frequency actuation you otherwise couldn't directly GET out of a pump;
B) Act as a "shock absorber" to help reduce "water hammer" effects, or
C) Allow a MUCH smaller "average capacity" pump to be used instead of a large "peak" one, for serious cost savings.

Just like with air, once an accumulator is pumped up, you can go crazy for a while with the actuators. However, pressures in a HYDRAULIC accumulator vessel can often exceed several THOUSAND PSI. The volume depends on your application.

The total energy stored is related to the total displacement volume times the maximum rated working pressure. IOW, a HECK of a lot of stored hydraulic energy can be had in just a TINY accumulator package, as much as a HUNDRED times higher than is available in OUR air based systems of the same size. "A couple thousand PSI" systems are fairly common. Anything over "a few thousand PSI" hydraulic systems DO exist, but are VERY dangerous, and take special plumbing parts and rules to avoid ruptures.

For safety, systems with hydraulic accumulators MUST include a way to CAREFULLY purge the energy stored in them. The easiest schematically is to add a simple bleeder/purge valve between the high pressure side and the oil reservoir.

BTW, hydraulic systems can be much more complex, too. Some components (like decent servo valves) may require microscopic oil filtering to eliminate even tiny contaminants for proper operation. I've once been in situation where even cracking a system for a SIMPLE change may lead to a DAY of lost time refiltering the entire oil load. But that's an extreme case...

I worked with accumulated systems when I helped a well known auto company develop their hydraulic active suspension system. Trust me, you quickly develop a HEALTHY respect for the kind of stored energy that can make a multi-ton car make significant corrective motions several hundred times a second, using only a hydraulic pump similar in size to our FIRST air pump, and a hydraulic accumulator not much bigger than a large grapefruit! Your health and safety hinges on proper procedures and rituals, and you think TWICE before taking ANY action in the lab.

During R&D tests, we even once had a full sized car jump over a foot straight up into the air on powerup due to a software error. (Whoops...) You might say, "there were puddles everywhere"... Trust me though, not ONE of them was the car's hydraulic fluid!

...And THAT is why we don't include even NON-accumulated hydraulics in FIRST contests, and seriously limit working pressures! If you think an air piston can be dangerous, imagine a TINY hydraulic system which can EASILY produce THOUSANDS of pounds of crushing force in a gripper using with an itty bitty cylinder. In addition, hydraulic oil spray from a leaky high pressure connection intersecting a person can "pressure inject" oil directly under or even THROUGH your skin. NOT fun, and it may require some messy surgery to attempt to clean it out. (I've seen it happen... Luckily, it was an arm and not a FACE...)

But ACCUMULATED hydraulics are WORSE. They're that dangerous WELL AFTER the power is cut off. One mistake with a well sealed but unpurged multi-K PSI accumulator based system (even DAYS later) could easily be crippling, or fatal. On the suspension project, we had some SERIOUS safety classes before we could even get NEAR the project hardware.

Now, I don't mean to scare anyone off from the field. Accumulated Hydraulic systems are VERY USEFUL, and some things simply can't be easily done WITHOUT them. But they're VERY serious systems, not something to "play with" as a first time user. Air is MUCH better for learning on, and teaches you the same things with fewer safety issues. NEXT comes Basic Hydraulics, and THEN Accumulated and "High Pressure" Hydraulics.

I'm SURE we'll be sticking with low pressure, "limited storage" air for THIS contest. I just want people to know that the field of "Accumulated Hydraulics" EXISTS, and can be quite exciting!

(I hope this has been informative...)

- Keith
__________________
Keith McClary - Organizer/Mentor/Sponsor - Ann Arbor MI area FIRST teams
ACTI - Automation Computer Technologies, Inc. (Sponsoring FIRST teams since 2001!)
MI Robot Club (Trainer) / GO-Tech Maker's Club / RepRap-Michigan) / SEMI CNC Club
"Certifiably Insane": Started FIVE FRC teams & many robot clubs (so far)!
2002: 830 "Rat Pack" | 2003-5;14: 1015;1076 "Pi Hi Samurai" | 2005-6: 1549 "Washtenuts"/"Fire Traxx"
2005-(on): 1502 "Technical Difficulties" | 2006-(on): FIRST Volunteer!
2009-(on): 470 "Alpha Omega" | WAFL | Sponsor & "Floating Engineer" for MI Dist 13 (Washtenaw Cnty)
2011: 3638 "Tigertrons" | 2013-(on): 4395 "ViBots" | 2014-(on) 66 "Grizzlies"
"Home" Teams: 66, 470, 1076, 1502, 4395
Local FIRST alumni at or coming to Ann Arbor (UM/EMU/WCC/Cleary)?
...We Want YOU as a Mentor! Please email me for info!
Support CDF Reputation - If a posting helped, thank 'em with rep points!
"It must be FRC build season when your spouse and children become 'Action Items 8 & 9'..."

Last edited by kmcclary : 11-04-2004 at 00:51.
  #19   Spotlight this post!  
Unread 11-04-2004, 00:56
pryoplasm's Avatar
pryoplasm pryoplasm is offline
Pit Crew/Electrical
AKA: Russ
#0069
 
Join Date: Jan 2004
Location: Quincy, Ma
Posts: 73
pryoplasm can only hope to improve
Re: "hydraulics"

Quote:
Originally Posted by greencactus3
fill 4 tanks to 120 psi. release all the air into an aluminum tube with inside diameter of 3/8..... ther is a steel 3/8 rod inside.....
goes through a couple pizza boxes and quite a bit more.....
now WHO says hydraulics are more fun than pneumatics???

EDIT: make sure you have your safety goggles on!!!
we might have done something similar with a single tank, 100 psi and launching a drywall screw through a piece of 1/4" plywood....also rigged it to a air horn for some ear drumming good fun, we almost defeaned, well half the team at 100 psi....hearing protection for the people running the horn a must, after the first try my ears were ringing for the rest of the day...
__________________
Cut these eyes, but I will see,
Kiss these lying lips for me,
Stroke this skin, and I will kneel,
Brutalize me, I will heal...
-KMFDM
  #20   Spotlight this post!  
Unread 11-04-2004, 03:02
michael_obrien's Avatar
michael_obrien michael_obrien is offline
Registered User
#0972 (LGHS Robotics)
Team Role: Student
 
Join Date: Sep 2003
Location: Los Gatos, CA
Posts: 17
michael_obrien is on a distinguished road
Re: "hydraulics"

try clamping a fire extinguisher to a skateboard and then knocking the head off of the thing with a hammer.
__________________

Michael O'Brien
Student
Los Gatos High School team #972
  #21   Spotlight this post!  
Unread 12-04-2004, 13:28
Unsung FIRST Hero Woodie Flowers Award
Chris Fultz Chris Fultz is offline
My Other Car is a 500 HP Turbine
FRC #0234 (Cyber Blue)
Team Role: Engineer
 
Join Date: Jan 2002
Rookie Year: 1942
Location: Indianapolis, IN
Posts: 2,837
Chris Fultz has a reputation beyond reputeChris Fultz has a reputation beyond reputeChris Fultz has a reputation beyond reputeChris Fultz has a reputation beyond reputeChris Fultz has a reputation beyond reputeChris Fultz has a reputation beyond reputeChris Fultz has a reputation beyond reputeChris Fultz has a reputation beyond reputeChris Fultz has a reputation beyond reputeChris Fultz has a reputation beyond reputeChris Fultz has a reputation beyond repute
Re: "hydraulics" - HOLD ON!

This post contains a great deal of very positive and beneficial information. It is also starting to contain some ideas and actions that are extremely dangerous and could cause serious injuries, even death, if something goes wrong. You are proposing messing with some powerful energy sources.

Please refrain from this type of discussion in this forum. Focus on robotics and topics related to them and lets keep everyone healthy.
__________________
Chris Fultz
Cyber Blue - Team 234
2016 IRI Planning Committee
2016 IndyRAGE Planning Committee
2010 - Woodie Flowers Award - Championship
  #22   Spotlight this post!  
Unread 16-01-2005, 15:06
robotfyrman robotfyrman is offline
Registered User
AKA: Shaun
FRC #1388 (Eagle Robotics)
Team Role: Student
 
Join Date: Nov 2004
Rookie Year: 2004
Location: Arroyo Grande, CA
Posts: 2
robotfyrman is an unknown quantity at this point
Send a message via AIM to robotfyrman Send a message via Yahoo to robotfyrman
Re: "hydraulics"

Quote:
Originally Posted by greencactus3
fill 4 tanks to 120 psi. release all the air into an aluminum tube with inside diameter of 3/8..... ther is a steel 3/8 rod inside.....
goes through a couple pizza boxes and quite a bit more.....
now WHO says hydraulics are more fun than pneumatics???

EDIT: make sure you have your safety goggles on!!!
I think I'm going to have to stick with hydraulics because that is what powers the Jaws-of-Life. Yes they move slow, but when you hear the hinge of a car door pop, It's well worth the wait.
  #23   Spotlight this post!  
Unread 16-01-2005, 15:15
Barry Bonzack's Avatar
Barry Bonzack Barry Bonzack is offline
Impossible to rain on my parade.
FRC #1902 (Exploding Bacon)
 
Join Date: Apr 2004
Rookie Year: 2003
Location: Orlando, FL
Posts: 1,776
Barry Bonzack has a reputation beyond reputeBarry Bonzack has a reputation beyond reputeBarry Bonzack has a reputation beyond reputeBarry Bonzack has a reputation beyond reputeBarry Bonzack has a reputation beyond reputeBarry Bonzack has a reputation beyond reputeBarry Bonzack has a reputation beyond reputeBarry Bonzack has a reputation beyond reputeBarry Bonzack has a reputation beyond reputeBarry Bonzack has a reputation beyond reputeBarry Bonzack has a reputation beyond repute
Send a message via AIM to Barry Bonzack
Re: "hydraulics"

For some reason the question "Can I sit on it?" has been asked often.

Edit: Even when its not moving
__________________


Chair of Florida FIRST Alumni
Orlando Regional Planning Committee
FIRST Tech Challenge Florida Leadership Team

Program Planner on the Orion Spacecraft at the Kennedy Space Center

Twitter: @FL_FIRST_Alumni













Events I'm Emceeing/Game Announcing:
1/10/2015 FTC Jacksonville League Championship
1/11/2015 FTC Central FL Tesla League Championship
1/17/2015 FTC South Florida League Championship
1/24/2015 FTC Tampa/St. Pete League Championship
2/7/2015 FLL Orlando Regional
2/14/2015 FTC State Championship
2/26-2/28/15 FRC South Florida Regional
3/8/2015 FLL State Championship
3/12-3/14/15 FRC Orlando Regional
4/22-4/25/15 FIRST World Championship Event - FTC Franklin Field

Last edited by Barry Bonzack : 16-01-2005 at 15:57.
  #24   Spotlight this post!  
Unread 16-01-2005, 15:35
russell's Avatar
russell russell is offline
Registered User
#1430 (WRONG)
Team Role: Electrical
 
Join Date: Feb 2004
Rookie Year: 2004
Location: Anchorage AK
Posts: 402
russell is a name known to allrussell is a name known to allrussell is a name known to allrussell is a name known to allrussell is a name known to allrussell is a name known to all
Re: "hydraulics"

its fun to try to ride on them.
  #25   Spotlight this post!  
Unread 16-01-2005, 16:50
Leav's Avatar
Leav Leav is offline
Spud Gun Division
AKA: Leav Oz-Ari
FRC #3316 (D-Bug)
Team Role: Mentor
 
Join Date: Dec 2004
Rookie Year: 2005
Location: Technion, Haifa, Israel
Posts: 774
Leav has a reputation beyond reputeLeav has a reputation beyond reputeLeav has a reputation beyond reputeLeav has a reputation beyond reputeLeav has a reputation beyond reputeLeav has a reputation beyond reputeLeav has a reputation beyond reputeLeav has a reputation beyond reputeLeav has a reputation beyond reputeLeav has a reputation beyond reputeLeav has a reputation beyond repute
Send a message via ICQ to Leav Send a message via AIM to Leav Send a message via MSN to Leav
Re: "hydraulics"

Quote:
Originally Posted by russell
its fun to try to ride on them.

yeah, freshmen are comfy...
__________________
"We choose to build robots this season and do the other things; Not because they are easy, but because they are hard."
-Paraphrasing JFK

Participated in FIRST as a student: 2005-2006 (But still learning every season!)
Mentor: 2008 - ? (Team 2630 2008-2011, and Team 3316 since 2013)
Engineer: 2011 - ? (B.Sc. and M.Sc. in Mech. Eng. from the Technion IIT)
FIRST Volunteer - 2007 - ? (MC, FTA, FIRST Aid etc.)
  #26   Spotlight this post!  
Unread 16-01-2005, 20:34
ahecht's Avatar
ahecht ahecht is offline
'Luzer'
AKA: Zan
no team
Team Role: Alumni
 
Join Date: Dec 2001
Rookie Year: 2002
Location: Billerica, MA
Posts: 978
ahecht has a reputation beyond reputeahecht has a reputation beyond reputeahecht has a reputation beyond reputeahecht has a reputation beyond reputeahecht has a reputation beyond reputeahecht has a reputation beyond reputeahecht has a reputation beyond reputeahecht has a reputation beyond reputeahecht has a reputation beyond reputeahecht has a reputation beyond reputeahecht has a reputation beyond repute
Send a message via ICQ to ahecht Send a message via AIM to ahecht Send a message via Yahoo to ahecht
Re: "hydraulics"

Anyone who doubts that accumulated hydraulic systems are fast hasn't ridden any of the new "rocket coasters" such as Xcelerator, Storm Runner, Top Thrill Dragster, or (soon) Kingda Ka. Accelerating a train carrying 16 people from 0 to 120mps in 3 seconds isn't slow.
__________________
Zan Hecht

Scorekeeper: '05 Championship DaVinci Field/'10 WPI Regional
Co-Founder: WPI-EBOT Educational Robotics Program
Alumnus: WPI/Mass Academy Team #190
Alumnus (and founder): Oakwood Robotics Team #992


"Life is an odd numbered problem the answer isn't in the back of the book." — Anonymous WPI Student
  #27   Spotlight this post!  
Unread 17-01-2005, 14:52
kmcclary's Avatar
kmcclary kmcclary is offline
Founder 830/1015;Mentor 66/470/1502
FRC #0470 (Alpha Omega Robotics)
Team Role: Engineer
 
Join Date: Aug 2001
Rookie Year: 1994
Location: Ann Arbor, MI
Posts: 491
kmcclary has a reputation beyond reputekmcclary has a reputation beyond reputekmcclary has a reputation beyond reputekmcclary has a reputation beyond reputekmcclary has a reputation beyond reputekmcclary has a reputation beyond reputekmcclary has a reputation beyond reputekmcclary has a reputation beyond reputekmcclary has a reputation beyond reputekmcclary has a reputation beyond reputekmcclary has a reputation beyond repute
Re: "hydraulics"

Quote:
Originally Posted by robotfyrman
I think I'm going to have to stick with hydraulics because that is what powers the Jaws-of-Life. Yes they move slow, but when you hear the hinge of a car door pop, It's well worth the wait.
Sorry Shaun, but no hydraulics are allowed in this contest... Pneumatics only, at the above mentioned specs.

But I'll admit, a couple of years back I saw a 12HP hydraulic driven ZTR lawnmower for sale and was sorely tempted to buy it. I could just imagine hacking it into my own personal Transformer style "FIRST Robot of Doom" for an outdoor "yard version" of a standard FIRST contest bot...

Gee... Can you imagine playing Stack Attack in a gravel pit "arena", using people riding in the (secured) cages of hacked Bobcat forklifts, trying to collect and stack large wooden crates over a large center hillock?

- Keith
__________________
Keith McClary - Organizer/Mentor/Sponsor - Ann Arbor MI area FIRST teams
ACTI - Automation Computer Technologies, Inc. (Sponsoring FIRST teams since 2001!)
MI Robot Club (Trainer) / GO-Tech Maker's Club / RepRap-Michigan) / SEMI CNC Club
"Certifiably Insane": Started FIVE FRC teams & many robot clubs (so far)!
2002: 830 "Rat Pack" | 2003-5;14: 1015;1076 "Pi Hi Samurai" | 2005-6: 1549 "Washtenuts"/"Fire Traxx"
2005-(on): 1502 "Technical Difficulties" | 2006-(on): FIRST Volunteer!
2009-(on): 470 "Alpha Omega" | WAFL | Sponsor & "Floating Engineer" for MI Dist 13 (Washtenaw Cnty)
2011: 3638 "Tigertrons" | 2013-(on): 4395 "ViBots" | 2014-(on) 66 "Grizzlies"
"Home" Teams: 66, 470, 1076, 1502, 4395
Local FIRST alumni at or coming to Ann Arbor (UM/EMU/WCC/Cleary)?
...We Want YOU as a Mentor! Please email me for info!
Support CDF Reputation - If a posting helped, thank 'em with rep points!
"It must be FRC build season when your spouse and children become 'Action Items 8 & 9'..."

Last edited by kmcclary : 17-01-2005 at 14:58.
  #28   Spotlight this post!  
Unread 17-01-2005, 15:43
CJO's Avatar
CJO CJO is offline
Emeritus Pain in the $@#$@#$@#
AKA: Christopher J. O'Connell
None #1097 (Site 3 Engineering)
Team Role: Alumni
 
Join Date: Feb 2003
Location: Latrobe (over the rainbow), CA
Posts: 217
CJO will become famous soon enoughCJO will become famous soon enough
Re: "hydraulics"

Ummm, isn't air a fluid? I mean, to all intents and purposes doesn't fluid dynamics deal with "liquids" and "gasses?"
__________________
Team 1097 -- Site 3 Engineering
~~~~~~~~~~~~~~~~~~~~
2003 Sacramento Rookie All Star
2003 Silicon Valley Rookie All Star
2004 Sacramento Engineering Inspiration Award
2004 Sacramento Visualization Award
2004 Outstanding Volunteer Award (G. Glasser)
2004 Silicon Valley Sportsmanship Award
2004 National Visualization Runner Up
2004 Cal Games Finalist
2005 Sacramento Sportsmanship Award
2005 Sacramento #1 seed
2005 Sacramento Finalist

2005 Silicon Valley Sportsmanship Award
2005 Silicon Valley #1 Seed
2005 Silicon Valley Finalist

  #29   Spotlight this post!  
Unread 17-01-2005, 16:34
kmcclary's Avatar
kmcclary kmcclary is offline
Founder 830/1015;Mentor 66/470/1502
FRC #0470 (Alpha Omega Robotics)
Team Role: Engineer
 
Join Date: Aug 2001
Rookie Year: 1994
Location: Ann Arbor, MI
Posts: 491
kmcclary has a reputation beyond reputekmcclary has a reputation beyond reputekmcclary has a reputation beyond reputekmcclary has a reputation beyond reputekmcclary has a reputation beyond reputekmcclary has a reputation beyond reputekmcclary has a reputation beyond reputekmcclary has a reputation beyond reputekmcclary has a reputation beyond reputekmcclary has a reputation beyond reputekmcclary has a reputation beyond repute
Re: "hydraulics"

Quote:
Originally Posted by CJO
Ummm, isn't air a fluid? I mean, to all intents and purposes doesn't fluid dynamics deal with "liquids" and "gasses?"
Yes it is a "fluid", but please don't confuse the behavior of "liquid" vs "gas" forms.

It's mostly a question of semantics. You'll mostly find the term "Hydraulics" is traditionally used to refer to "liquid only" power transfer mediums, and "Pneumatics" to refer to "gaseous only" power transfer mediums. As long as you're not compressing the "working fluid" enough to phase change the medium, this distinction is fine.

The major difference is "compressibility". Gasses are compressible, whereas fluids are not. IOW, pneumatic systems provide its own "spring function" between the energy source and the load, while hydraulic systems act more like a hard mechanical linkage. Otherwise, they have similar characteristics. Both will give you controllable Mechanical Advantage, very flexible energy transfer without complex mechanical linkages (hoses are simpler than gears and shafts!), and (unlike electric motors) "infinite stallability without harm".

"Fluid Power" is the superset term, that covers BOTH pneumatics AND hydraulics. It is often used by university departments when teaching the subject. You should also definitely use it when referring to any power transfer medium that may undergo a phase change between liquid and gas depending on condition. (But honestly, most designs normally try hard to AVOID those situations... You either want compressibility, or you don't!)

<edit>
The confusion comes in because the COMMON usage of the term "fluid" in English IMPLIES a liquid. In scientific terms though, the "working fluid" can be any phase of material.

Oh yes, before someone chimes in with a joke, solid working fluids ARE possible, as long as they are particle systems. Things like sand, or a bunch of tiny ball bearings CAN be used as a "working fluid" (though I'm not sure it would be a good IDEA for use in OUR situation!) . Particle systems are a rather "weird" working fluid, but you CAN transfer force through them!
</edit>

- Keith
__________________
Keith McClary - Organizer/Mentor/Sponsor - Ann Arbor MI area FIRST teams
ACTI - Automation Computer Technologies, Inc. (Sponsoring FIRST teams since 2001!)
MI Robot Club (Trainer) / GO-Tech Maker's Club / RepRap-Michigan) / SEMI CNC Club
"Certifiably Insane": Started FIVE FRC teams & many robot clubs (so far)!
2002: 830 "Rat Pack" | 2003-5;14: 1015;1076 "Pi Hi Samurai" | 2005-6: 1549 "Washtenuts"/"Fire Traxx"
2005-(on): 1502 "Technical Difficulties" | 2006-(on): FIRST Volunteer!
2009-(on): 470 "Alpha Omega" | WAFL | Sponsor & "Floating Engineer" for MI Dist 13 (Washtenaw Cnty)
2011: 3638 "Tigertrons" | 2013-(on): 4395 "ViBots" | 2014-(on) 66 "Grizzlies"
"Home" Teams: 66, 470, 1076, 1502, 4395
Local FIRST alumni at or coming to Ann Arbor (UM/EMU/WCC/Cleary)?
...We Want YOU as a Mentor! Please email me for info!
Support CDF Reputation - If a posting helped, thank 'em with rep points!
"It must be FRC build season when your spouse and children become 'Action Items 8 & 9'..."

Last edited by kmcclary : 17-01-2005 at 16:56.
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


All times are GMT -5. The time now is 22:39.

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