Go to Post I think CD is worth about 3 billion in Google stock. Talk about one hell of a fundraiser! - Joe Matt [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 03-12-2010, 17:10
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
How do you build telescopes/forklifts?

Hi CD,

I've been involved with FIRST since 2005, but never been involved in building any kind of telescoping arm or forklift device.

I got to thinking about it and couldn't think about simple ideas on how to solve the main problems:

what slides past what? for telescoping I would think it would be a square tube within a square tube with some wheels or rollers to allow movement. But most forklifts use two sets of tubes to improve rigidity so how do you link them and allow them to slide?

I can't imagine drawer slides are used extensively since they weigh so much.

regarding opening the telescopes and lifts: I'm guessing the cable+drum+pulleys system is the standard but with the telescoping arms some things just don't add up regarding the way the cables need to wrap.

I would appreciate some explanations and also pics of said systems would be very much appreciated. I couldn't find any closeups.

I know FRC233 (Pink) is very strong with telescopes. any other teams to look out for?

Thanks for your help in educating myself and hopefully others!

-Leav
__________________
"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.)
  #2   Spotlight this post!  
Unread 03-12-2010, 17:19
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: 19,823
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: How do you build telescopes/forklifts?

It's been a while since 330 did one of their blue lifts...but the last time one of those broke, it was self-inflicted and it merely bent.

Lifts do not have to have their extending sections inside each other. In fact, it's a lot easier to do a cable-powered lift if they are not inside each other.

I'll mention cabling routes here...

There are 2 types: continuous and cascading. See this thread for explanation. (post #3) If cabling is used, it is best to ensure that there is a "gravity" cable to make sure that your lift can retract.
There are, of course, other means of telescoping.

If a 2-tube-set lift has the sections outside of each other, each "level" has a partner joined to it in the other set. Joints are typically at the bottom and on one side.

You might want to take a look at 25's section in the 2007 Behind the Design book, as well. There is another robot in there as well--19??--that had a telescoping arm, IIRC, but it was an internal-section one. Oh, and don't forget to look at 357 in the same book...
__________________
Past teams:
2003-2007: FRC0330 BeachBots
2008: FRC1135 Shmoebotics
2012: FRC4046 Schroedinger's Dragons

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

  #3   Spotlight this post!  
Unread 03-12-2010, 17:20
AdamHeard's Avatar
AdamHeard AdamHeard is offline
Lead Mentor
FRC #0973 (Greybots)
Team Role: Mentor
 
Join Date: Oct 2004
Rookie Year: 2004
Location: Atascadero
Posts: 5,526
AdamHeard has a reputation beyond reputeAdamHeard has a reputation beyond reputeAdamHeard has a reputation beyond reputeAdamHeard has a reputation beyond reputeAdamHeard has a reputation beyond reputeAdamHeard has a reputation beyond reputeAdamHeard has a reputation beyond reputeAdamHeard has a reputation beyond reputeAdamHeard has a reputation beyond reputeAdamHeard has a reputation beyond reputeAdamHeard has a reputation beyond repute
Send a message via AIM to AdamHeard
Re: How do you build telescopes/forklifts?

Quote:
Originally Posted by Leav View Post
Hi CD,

I've been involved with FIRST since 2005, but never been involved in building any kind of telescoping arm or forklift device.

I got to thinking about it and couldn't think about simple ideas on how to solve the main problems:

what slides past what? for telescoping I would think it would be a square tube within a square tube with some wheels or rollers to allow movement. But most forklifts use two sets of tubes to improve rigidity so how do you link them and allow them to slide?

I can't imagine drawer slides are used extensively since they weigh so much.

regarding opening the telescopes and lifts: I'm guessing the cable+drum+pulleys system is the standard but with the telescoping arms some things just don't add up regarding the way the cables need to wrap.

I would appreciate some explanations and also pics of said systems would be very much appreciated. I couldn't find any closeups.

I know FRC233 (Pink) is very strong with telescopes. any other teams to look out for?

Thanks for your help in educating myself and hopefully others!

-Leav
254/968 had a solid lift design as well.

There is a manipulator presentation from 330 (and I've seen others as well with this information) that outlines the more common ways of routing cable/chain for the lifting motion.

173 had a very unique design in 05, I think they reused it in 07 as well.
  #4   Spotlight this post!  
Unread 05-12-2010, 11:30
joek's Avatar
joek joek is offline
Team Welder and CAD tech
FRC #2052 (KnightKrawler)
Team Role: Mechanical
 
Join Date: Jan 2009
Rookie Year: 2009
Location: Irondale H.S.
Posts: 231
joek is an unknown quantity at this point
Re: How do you build telescopes/forklifts?

Quote:
Originally Posted by Leav View Post
Hi CD,

I've been involved with FIRST since 2005, but never been involved in building any kind of telescoping arm or forklift device.

I got to thinking about it and couldn't think about simple ideas on how to solve the main problems:

what slides past what? for telescoping I would think it would be a square tube within a square tube with some wheels or rollers to allow movement. But most forklifts use two sets of tubes to improve rigidity so how do you link them and allow them to slide?

I can't imagine drawer slides are used extensively since they weigh so much.

regarding opening the telescopes and lifts: I'm guessing the cable+drum+pulleys system is the standard but with the telescoping arms some things just don't add up regarding the way the cables need to wrap.

I would appreciate some explanations and also pics of said systems would be very much appreciated. I couldn't find any closeups.

I know FRC233 (Pink) is very strong with telescopes. any other teams to look out for?

Thanks for your help in educating myself and hopefully others!

-Leav
we did this in '08 with 80/20 and some sort of sliders, using pulleys and rope to lift it
__________________


2012 Record (13-2-0)
lake superior regional finalists- thank you WAVE (2826) and Blue Twilight (2220)
  #5   Spotlight this post!  
Unread 05-12-2010, 12:19
lbarger's Avatar
lbarger lbarger is offline
Senior LRI NC District
AKA: Lee Barger
FRC #0587 (The Hedgehogs)
Team Role: Mentor
 
Join Date: Dec 2005
Rookie Year: 2001
Location: Hillsborough, NC
Posts: 81
lbarger has much to be proud oflbarger has much to be proud oflbarger has much to be proud oflbarger has much to be proud oflbarger has much to be proud oflbarger has much to be proud oflbarger has much to be proud oflbarger has much to be proud oflbarger has much to be proud of
Re: How do you build telescopes/forklifts?

We've tried the 80/20 extrusion and Delrin sliders as well, but did not like the binding. That is why we went with draw slides.

With the extrusion/slider set up you typically need two sliders on each 'post' for stability. To minimize binding you want to keep the sliders as far apart as possible. This usually means mounting one slider at the top of the lower lift member and the bottom of the higher lift member. As the lift is extended, the slider on the upper member moves with it and gets closer to the the slider mounted on the lower member. Some experimentation can determine just how close the two sliders can approach without bind. You can then put in stops.

A general rule of thumb is bearing surfaces should be separated (lengthwise) about 3 times their diameter (or width). My experience suggests this may be a little close for 80/20 hardware so you may need 4 or 6 times the width. (For a 1" extrusion this means 4 to 6 inches between the slider pairs.)

One last though on bind: Aluminum is actually have fairly 'sticky' material. Can you substitute another material or cover the aluminum (plating, enamel, powder coat)? Dry lube sprays may also help.
  #6   Spotlight this post!  
Unread 05-12-2010, 12:40
Teched3 Teched3 is offline
Hodge1
FRC #0175 (BuzzRobotics)
Team Role: Mentor
 
Join Date: Apr 2006
Rookie Year: 1996
Location: Connecticut
Posts: 319
Teched3 has much to be proud ofTeched3 has much to be proud ofTeched3 has much to be proud ofTeched3 has much to be proud ofTeched3 has much to be proud ofTeched3 has much to be proud ofTeched3 has much to be proud ofTeched3 has much to be proud ofTeched3 has much to be proud of
Smile Re: How do you build telescopes/forklifts?

Just to add to some of the suggestions on multi-stage lifts, Team175 (Buzzrobotics) has used aluminum square tubing, aluminum round tubing, as well as PVC for the stages. Provide enough clearance for Delrin bearings on the aluminum so there is no metal-to-metal contact between stages, and also reduces friction between stages. Instead of using metal cable, we use Spectra braided Cord (1/8" - 1050 lb tensile strength) Which has lighter weight, and allows for much smaller pulley radii, saving weight and space. In addition, we used a double drum-one side to wind up cord for lift, and the second to wind down for retraction of the lift, driven off the same motor. We install an encoder or a multi-turn pot to control lift movement, and put tensioning rubber bands on the cable ends to provide some extra length that is needed due to cord overlap differences on the drums. This also keeps tension on the cord so they won't come off the pulleys. Good Luck prototyping cable routing.
__________________
Sweat the details
Why is there never enough time to do it right, but always enough time to do it again!
Even if you're on the right track, if you sit still, you'll get run over!!!
  #7   Spotlight this post!  
Unread 05-12-2010, 17:37
Unsung FIRST Hero
Al Skierkiewicz Al Skierkiewicz is offline
Broadcast Eng/Chief Robot Inspector
AKA: Big Al WFFA 2005
FRC #0111 (WildStang)
Team Role: Engineer
 
Join Date: Jun 2001
Rookie Year: 1996
Location: Wheeling, IL
Posts: 10,798
Al Skierkiewicz has a reputation beyond reputeAl Skierkiewicz has a reputation beyond reputeAl Skierkiewicz has a reputation beyond reputeAl Skierkiewicz has a reputation beyond reputeAl Skierkiewicz has a reputation beyond reputeAl Skierkiewicz has a reputation beyond reputeAl Skierkiewicz has a reputation beyond reputeAl Skierkiewicz has a reputation beyond reputeAl Skierkiewicz has a reputation beyond reputeAl Skierkiewicz has a reputation beyond reputeAl Skierkiewicz has a reputation beyond repute
Re: How do you build telescopes/forklifts?

Leav,
We have used manufactured slides in the past. I think our Triple Play robot used slides from McMaster. In other years we have manufactured our own using sheet aluminum bent to nest and telescope. Almost exclusively we use Spectra cable I think from McMaster. It is pretty amazing stuff as far as strength vs. size. We manufacture cable reels using delrin and string them through each section of lift from top to bottom of each section. As the reel pulls on the cable it becomes shorter raising the sections. If you design for two sides to lift, I recommend using a dual reel so that the cables are drawn at the same speed and distance. We have generally used FP motors or window motors in the lifts in the past.
__________________
Good Luck All. Learn something new, everyday!
Al
WB9UVJ
www.wildstang.org
________________________
Storming the Tower since 1996.
  #8   Spotlight this post!  
Unread 05-12-2010, 22:06
Jeff Pahl's Avatar
Jeff Pahl Jeff Pahl is offline
likes to look at shiny things...
FRC #5148 (New Berlin Blitz)
Team Role: Engineer
 
Join Date: Oct 2004
Rookie Year: 2004
Location: Waukesha, WI
Posts: 344
Jeff Pahl has a reputation beyond reputeJeff Pahl has a reputation beyond reputeJeff Pahl has a reputation beyond reputeJeff Pahl has a reputation beyond reputeJeff Pahl has a reputation beyond reputeJeff Pahl has a reputation beyond reputeJeff Pahl has a reputation beyond reputeJeff Pahl has a reputation beyond reputeJeff Pahl has a reputation beyond reputeJeff Pahl has a reputation beyond reputeJeff Pahl has a reputation beyond repute
Re: How do you build telescopes/forklifts?

Don't even think about trying to telescope aluminum tubing without some sort of non-metalic "bearings" between the tubes. Just grease alone will not work. Trust me on this one....
__________________
Team 5148 - 2014 Wisconsin Regional Rookie All-Stars!!

Mentor: 1379: 2004-2008 / 2530: 2008-2013 / 2861: 2009 / 5148: 2014-??
Lead Robot Inspector: 10,000 Lakes '09 - '11 / Lake Superior '11-'12 / Northern Lights '13, '15 - '16 / Championship '09 - '12, '14 - '15
Attending/Inspecting 2017: TBD, Wisconsin, STL Championship

"Sometimes the questions are complicated and the answers are simple" -Dr. Seuss
  #9   Spotlight this post!  
Unread 05-12-2010, 22:26
ericzundel ericzundel is offline
Mentor
AKA: Eric Ayers
FRC #1795
Team Role: Mentor
 
Join Date: Jan 2010
Rookie Year: 2006
Location: Atlanta
Posts: 12
ericzundel is an unknown quantity at this point
Re: How do you build telescopes/forklifts?

More from the Team 1379 First Overdrive robot experience. We had one square section of aluminum permanently embedded in another. Everyone laughed when I tried to take it out one day.

We machined blocks of Delrin as sliders, but the tolerances were still very tight even with liberal amounts of grease and had to be re-machined a couple of times if I remember correctly. I wouldn't dismiss the 80/20 linear sliding solutions so quickly. Besides the bearings, they have pre-engineered rollers or you could make your own to fit in those slots.
__________________
2009-2011 Mentor Team 1795 http://sites.google.com/site/first1795
2006-2008 Mentor Team 1379
  #10   Spotlight this post!  
Unread 05-12-2010, 22:40
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: 19,823
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: How do you build telescopes/forklifts?

330, when they used lifts, used Al C-channel. We'd weld two pieces into an I-beam if we needed extra height over what we could get out of our base pair of sections, and then put the I-beam in between the C-channels. The bottom ends would be fastened together (we used a 2-tower system); the tops would be fastened on the lower side. Each piece had a delrin roller at top or bottom, 2 rollers to a sliding pair. The cabling was steel cable, properly crimped at the ends, cascading run, IIRC. Oh, and we had a gravity cable to make sure the lift came down. 2 FPs through stock gearboxes and a winch drum.
__________________
Past teams:
2003-2007: FRC0330 BeachBots
2008: FRC1135 Shmoebotics
2012: FRC4046 Schroedinger's Dragons

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

  #11   Spotlight this post!  
Unread 06-12-2010, 10:19
Brandon Holley's Avatar
Brandon Holley Brandon Holley is offline
Chase perfection. Catch excellence.
AKA: Let's bring CD back to the way it used to be
FRC #0125 (NU-TRONs, Team #11 Alumni (GO MORT))
Team Role: Engineer
 
Join Date: Jan 2004
Rookie Year: 2001
Location: Boston, MA
Posts: 2,593
Brandon Holley has a reputation beyond reputeBrandon Holley has a reputation beyond reputeBrandon Holley has a reputation beyond reputeBrandon Holley has a reputation beyond reputeBrandon Holley has a reputation beyond reputeBrandon Holley has a reputation beyond reputeBrandon Holley has a reputation beyond reputeBrandon Holley has a reputation beyond reputeBrandon Holley has a reputation beyond reputeBrandon Holley has a reputation beyond reputeBrandon Holley has a reputation beyond repute
Send a message via AIM to Brandon Holley
Re: How do you build telescopes/forklifts?

One simple comment I will make here is to never underestimate friction. When designing something like a lift where you know you will have a surface needing to rub, roll or slide on another, do not underestimate friction. The amount of resistive force (to lifting) that can result from a poorly designed sliding interface can be staggering.


Also, try to counterbalance your lifter with springs or weight if possible. It will not only make the lift easier to operate (ie: less load on the system), it will also make the system much more consistent and repeatable.


-Brando
__________________
MORT (Team 11) '01-'05 :
-2005 New Jersey Regional Chairman's Award Winners
-2013 MORT Hall of Fame Inductee

NUTRONs (Team 125) '05-???
2007 Boston Regional Winners
2008 & 2009 Boston Regional Driving Tomorrow's Technology Award
2010 Boston Regional Creativity Award
2011 Bayou Regional Finalists, Innovation in Control Award, Boston Regional Finalists, Industrial Design Award
2012 New York City Regional Winners, Boston Regional Finalists, IRI Mentor of the Year
2013 Orlando Regional Finalists, Industrial Design Award, Boston Regional Winners, Pine Tree Regional Finalists
2014 Rhode Island District Winners, Excellence in Engineering Award, Northeastern University District Winners, Industrial Design Award, Pine Tree District Chairman's Award, Pine Tree District Winners
2015 South Florida Regional Chairman's Award, NU District Winners, NEDCMP Industrial Design Award, Hopper Division Finalists, Hopper/Newton Gracious Professionalism Award
  #12   Spotlight this post!  
Unread 06-12-2010, 10:47
Jon Stratis's Avatar
Jon Stratis Jon Stratis is offline
Mentor, LRI, MN RPC
FRC #2177 (The Robettes)
Team Role: Mentor
 
Join Date: Feb 2007
Rookie Year: 2006
Location: Minnesota
Posts: 3,834
Jon Stratis has a reputation beyond reputeJon Stratis has a reputation beyond reputeJon Stratis has a reputation beyond reputeJon Stratis has a reputation beyond reputeJon Stratis has a reputation beyond reputeJon Stratis has a reputation beyond reputeJon Stratis has a reputation beyond reputeJon Stratis has a reputation beyond reputeJon Stratis has a reputation beyond reputeJon Stratis has a reputation beyond reputeJon Stratis has a reputation beyond repute
Re: How do you build telescopes/forklifts?

I know I have some better close up pictures at home, PM me your e-mail address if you'd like them. This is from our Overdrive robot:

http://www.chiefdelphi.com/media/photos/30270
http://www.chiefdelphi.com/media/photos/30267

The whole thing is pretty straight forward:
- Each stage fits inside of another stage, loose enough that it doesn't bind, but tight enough that it doesn't wiggle loose.
- At specific points, there are brackets that hold small wheels on (you can see one of the wheels at the top of the first picture) in order to hold the whole thing together. The outer most stationary section has the wheels bolted to the top, and the middle section fits inside of those wheels. Then the middle section has wheels bolted to the bottom that wrap around the outer section. As you pull the middle section up, the wheels get closer together. As you can imagine, this means there's more stability when it's all the way down, versus all the way up... but still stable enough for our purposes.
- We used a big drum at the bottom, powered by a motor, to lift the arm, and allowed gravity to lower it as we ran the drum in reverse. The cable routing went from the drum to a fixed pulley at the top, down to a pulley attached to the bottom of the middle stage, up to a fixed pulley at the top of the middle stage, and finally down to terminate at the bottom of the inner stage. If required, you could run a cable opposite this one on the same drum to pull it down.
  #13   Spotlight this post!  
Unread 07-12-2010, 11:50
Jon Stratis's Avatar
Jon Stratis Jon Stratis is offline
Mentor, LRI, MN RPC
FRC #2177 (The Robettes)
Team Role: Mentor
 
Join Date: Feb 2007
Rookie Year: 2006
Location: Minnesota
Posts: 3,834
Jon Stratis has a reputation beyond reputeJon Stratis has a reputation beyond reputeJon Stratis has a reputation beyond reputeJon Stratis has a reputation beyond reputeJon Stratis has a reputation beyond reputeJon Stratis has a reputation beyond reputeJon Stratis has a reputation beyond reputeJon Stratis has a reputation beyond reputeJon Stratis has a reputation beyond reputeJon Stratis has a reputation beyond reputeJon Stratis has a reputation beyond repute
Re: How do you build telescopes/forklifts?

As requested, here are the best close ups I have of that robot:





Also, you can see it in action at TBA:
http://www.thebluealliance.net/tbatv/match/2008mn_f1m2
Check out 0:48, 1:06, 1:36, and 2:03

Last edited by Jon Stratis : 07-12-2010 at 11:55.
  #14   Spotlight this post!  
Unread 26-12-2010, 22:36
Mr_I's Avatar
Mr_I Mr_I is offline
Registered User
AKA: Tom Indelicato, 811 Moderator, Mentor, Parent, ...
FRC #0811 (Cardinals)
Team Role: Teacher
 
Join Date: Feb 2002
Rookie Year: 2001
Location: Nashua, NH
Posts: 194
Mr_I has a brilliant futureMr_I has a brilliant futureMr_I has a brilliant futureMr_I has a brilliant futureMr_I has a brilliant futureMr_I has a brilliant futureMr_I has a brilliant futureMr_I has a brilliant futureMr_I has a brilliant futureMr_I has a brilliant futureMr_I has a brilliant future
Re: How do you build telescopes/forklifts?

Leav,
In our 10 year history, we tried a telescoping pole only once: in 2004, our robot lifted a grappling hook 15' up to grab the bar. We used multiple lengths of PVC pipe of various diameters, so that each section nestled into the next, and we used cascading cabling using 600 lb test Kevlar cord (as we hadn't discovered spectra cable yet). The results are why we never used telescoping poles since.
The first stage cabling was under such high stress that it snapped repeatedly, forcing a complex restringing. We used a dual-diameter capstan pulley to pull the poles back down, since the pole was pivoted to aim for the bar, and as such we couldn't rely on gravity. We designed and built the capstans ourselves to match the geometry of the pole. We used a window motor to do the lifting and retracting.

If we ever have cause to lift again, we will hopefully never use that design again. Even though the pipe sections slid nicely, friction was a big issue. Spectra cable with (pulleys around turns!) is a must, unless you go a chain & sprocket route. And I would concur with others that draw glides are a good approach, as they are likely manufactured to higher tolerances than you can do in the shop in 6 weeks.
__________________
"It's NOT Just A Robot Thing!"
  #15   Spotlight this post!  
Unread 27-12-2010, 00:19
PingPongPerson's Avatar
PingPongPerson PingPongPerson is offline
Hardcore Robot Addict
AKA: Michael Groom
FRC #0955 (CV Robotics)
Team Role: Mentor
 
Join Date: Nov 2009
Rookie Year: 2008
Location: Corvallis, OR
Posts: 69
PingPongPerson will become famous soon enough
Re: How do you build telescopes/forklifts?

You mentioned fitting square tube inside itself. Though it is doable, I know that it has a tendency to bind up a lot unless perfectly attached.
__________________

Team 955
Raiderbot
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
How many of you build your own field? Jessica Boucher General Forum 43 07-03-2006 21:15
[ECDU]: How involved in the build are you? Steve Howland FIRST-related Organizations 7 08-03-2005 12:12
How long did it take for you to build your drivetrain? NoodleKnight Technical Discussion 18 29-12-2004 16:13
How many of you build computers? Alphawolf829 Chit-Chat 8 15-01-2003 16:19
how do you build a robot? archiver 2001 1 24-06-2002 01:59


All times are GMT -5. The time now is 08:33.

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