OCCRA
Go to Post I understand that Dean Kaymen has now invented a super "sniffer" that can scout-out anyone within hearing distance that is remotely-involved with FIRST. - dhitchco [more]
Home
Go Back   Chief Delphi > Technical > Technical Discussion
CD-Events   CD-Media   CD-Spy   FRC-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 03-12-2012, 07:52 PM
mlantry mlantry is online now
wishing for college to come sooner
no team
Team Role: Alumni
 
Join Date: Jan 2011
Rookie Year: 2011
Location: hillsdale NJ
Posts: 236
mlantry is a splendid one to beholdmlantry is a splendid one to beholdmlantry is a splendid one to beholdmlantry is a splendid one to beholdmlantry is a splendid one to beholdmlantry is a splendid one to beholdmlantry is a splendid one to behold
polycord and yellow belt

From what I've seen most teams (including ours) are either using yellow belt or polycord for an elevator from the ground to the shooter/ launching device. What is the worst thing that has happened with your teams cord whether its snapping or something else. I just curious if teams have problems with these things.
  #2   Spotlight this post!  
Unread 03-12-2012, 07:54 PM
dodar's Avatar
dodar dodar is offline
Registered User
AKA: Mike Doty
FRC #1592 (Bionic Tigers)
Team Role: Alumni
 
Join Date: Feb 2008
Rookie Year: 2007
Location: Cocoa, Florida
Posts: 2,342
dodar has a reputation beyond reputedodar has a reputation beyond reputedodar has a reputation beyond reputedodar has a reputation beyond reputedodar has a reputation beyond reputedodar has a reputation beyond reputedodar has a reputation beyond reputedodar has a reputation beyond reputedodar has a reputation beyond reputedodar has a reputation beyond reputedodar has a reputation beyond repute
Re: polycord and yellow belt

I'd say ours is the cords walking around on the rollers.
__________________
Fun as a Student: 89-57-4 and 1 banner in 4 years
Fun as a Bionic Tiger: 189-100-4 and 4 banners in 8 years

  #3   Spotlight this post!  
Unread 03-12-2012, 08:07 PM
DonRotolo's Avatar
DonRotolo DonRotolo is offline
Back to earth once again
FRC #1676 (Pascack PI Oneers)
Team Role: Mentor
 
Join Date: Jan 2005
Rookie Year: 2005
Location: Montvale NJ
Posts: 6,397
DonRotolo has a reputation beyond reputeDonRotolo has a reputation beyond reputeDonRotolo has a reputation beyond reputeDonRotolo has a reputation beyond reputeDonRotolo has a reputation beyond reputeDonRotolo has a reputation beyond reputeDonRotolo has a reputation beyond reputeDonRotolo has a reputation beyond reputeDonRotolo has a reputation beyond reputeDonRotolo has a reputation beyond reputeDonRotolo has a reputation beyond repute
Re: polycord and yellow belt

The worst thing that happened to our orange urethane belting is that students got this idea to cut and re-join it after almost every match "just in case". sheesh.
__________________

I am N2IRZ - What's your callsign?
Also visit TARPN to see what's up!
  #4   Spotlight this post!  
Unread 03-12-2012, 08:11 PM
mlantry mlantry is online now
wishing for college to come sooner
no team
Team Role: Alumni
 
Join Date: Jan 2011
Rookie Year: 2011
Location: hillsdale NJ
Posts: 236
mlantry is a splendid one to beholdmlantry is a splendid one to beholdmlantry is a splendid one to beholdmlantry is a splendid one to beholdmlantry is a splendid one to beholdmlantry is a splendid one to beholdmlantry is a splendid one to behold
Re: polycord and yellow belt

Oh Don i never told u we only did it at the most twice a day
  #5   Spotlight this post!  
Unread 03-12-2012, 08:18 PM
470-RBTX's Avatar
470-RBTX 470-RBTX is offline
Team Schmooze Captain
AKA: Joel Hurd
FRC #0470 (Alpha Omega Robotics)
Team Role: Driver
 
Join Date: Jan 2012
Rookie Year: 2008
Location: Ypsilanti
Posts: 22
470-RBTX has much to be proud of470-RBTX has much to be proud of470-RBTX has much to be proud of470-RBTX has much to be proud of470-RBTX has much to be proud of470-RBTX has much to be proud of470-RBTX has much to be proud of470-RBTX has much to be proud of470-RBTX has much to be proud of
Re: polycord and yellow belt

The poly belting is some of the most durable stuff I've ever seen and used. 470 used belting from our Lunacy bot (which has endured 3 FIM competitions and countless demonstrations) on this years robot, and have had no problems with it. We just cut it to dimension and and rejoin it and it keeps holding strong, in the 3 years of us using that robot it's never snapped.
  #6   Spotlight this post!  
Unread 03-13-2012, 11:21 AM
artdutra04's Avatar
artdutra04 artdutra04 is offline
VEX Robotics Engineer
AKA: Arthur Dutra IV; NERD #18
FRC #0148 (Robowranglers)
Team Role: Engineer
 
Join Date: Mar 2005
Rookie Year: 2002
Location: Greenville, TX
Posts: 3,022
artdutra04 has a reputation beyond reputeartdutra04 has a reputation beyond reputeartdutra04 has a reputation beyond reputeartdutra04 has a reputation beyond reputeartdutra04 has a reputation beyond reputeartdutra04 has a reputation beyond reputeartdutra04 has a reputation beyond reputeartdutra04 has a reputation beyond reputeartdutra04 has a reputation beyond reputeartdutra04 has a reputation beyond reputeartdutra04 has a reputation beyond repute
Re: polycord and yellow belt

Quote:
Originally Posted by mlantry View Post
Oh Don i never told u we only did it at the most twice a day
That's probably doing more harm than good. If you melt the ends together and then immediately install it and put it under tension, the joint will not be as strong and that may lead to failures.

Properly welded polycord should last for years without failure (tons of factories and warehouses use polycord in their conveyor systems), but the only way to properly weld it is to let the welded joint fully cure for 30-60 minutes under zero tension.

If you do polycord right the first time on a FRC robot, you should never have to redo it.
__________________
Art Dutra IV
Robotics Engineer, VEX Robotics, Inc., a subsidiary of Innovation First International (IFI)
Robowranglers Team 148 | GUS Robotics Team 228 (Alumni) | Rho Beta Epsilon (Alumni) | @arthurdutra

世上无难事,只怕有心人.
  #7   Spotlight this post!  
Unread 03-13-2012, 12:20 PM
Peter Matteson's Avatar
Peter Matteson Peter Matteson is offline
Ambitious but rubbish!
FRC #0177 (Bobcat Robotics)
Team Role: Engineer
 
Join Date: Sep 2003
Rookie Year: 2003
Location: South Windsor, CT
Posts: 1,629
Peter Matteson has a reputation beyond reputePeter Matteson has a reputation beyond reputePeter Matteson has a reputation beyond reputePeter Matteson has a reputation beyond reputePeter Matteson has a reputation beyond reputePeter Matteson has a reputation beyond reputePeter Matteson has a reputation beyond reputePeter Matteson has a reputation beyond reputePeter Matteson has a reputation beyond reputePeter Matteson has a reputation beyond reputePeter Matteson has a reputation beyond repute
Re: polycord and yellow belt

Quote:
Originally Posted by DonRotolo View Post
The worst thing that happened to our orange urethane belting is that students got this idea to cut and re-join it after almost every match "just in case". sheesh.
That is a bad idea. I make our students wait at least 15min before putting any load on the cord after welding because the weld needs to cool and solidify. Changing it that quick sounds like a bad idea.

We have green polycord from 2004 and orange from 2006 that still work fine.

Quote:
Originally Posted by Jared341 View Post
After using flat urethane belting for the first time this year, we will probably never use round polycord again (except if we need a crossed belt somewhere).



Easy to weld (overlap, hit with a heat gun, and press with something flat to square the weld. Turn over and repeat). Doesn't require grooves (just build up a crown out of tape and the belt self centers, see: http://www.lhup.edu/~dsimanek/scenario/crowning.htm).

Our rollers are just aluminum tubes with bearings pressed in each end.
We used those last year on our roller claw, and I liked them a lot, but for what we did with our intake I needed to use round for cross over and wanted to keep it consistent.

Also for keeping our belts tracking we cut rings of 1/8" that we welded to the .049" wall Al tube that forms our rollers. Not the most efficient or fastest way to make belt guides but it's signifigantly lighter than anything else we've tried.
__________________
2011 Championship Finalists/Archimedes Division Championships w/ 2016 & 781
2010 Championship Winners/Newton Division Champions
Thank-you 294 & 67

2009 Newton Division Champions w/ 1507 & 121
2008 Archimedes Division Champions w/ 1124 & 1024
2007 Championship Winners/Newton Division Champions w/190, 987 & 177 The Wall of Maroon
2006 Galileo Division Champions w/ 1126 & 201
www.bobcatrobotics.org
"If you can't do it with brains, it won't be done with hours." - Clarence "Kelly" Johnson
  #8   Spotlight this post!  
Unread 03-12-2012, 08:18 PM
quinxorin quinxorin is offline
Mentor now :(
AKA: Ian Pudney
FRC #0862 (Lightning Robotics)
Team Role: Mentor
 
Join Date: Jan 2009
Rookie Year: 2009
Location: Lightning Robotics
Posts: 148
quinxorin will become famous soon enough
Re: polycord and yellow belt

We've been using polycord since 2010, and honestly, no problems. As long as we follow the instructions and cut it 11% shorter than measured, it works beautifully. It doesn't just work for applications like collecting balls; if you want to prevent a motor from stalling, use polycord on a pully designed for a toothed belt, and the polycord will start to slip before the motor stalls. You can change its tension to adjust how much force it takes to make it slip.

The belts on our grabber in 2011 would fall off every once in a while, but that was more a symptom of the design of the rollers than anything else. It wasn't a problem, either; there were 4 belts on each side, and it only took 1 for the grabber to work. It was also the only part of the robot that worked at all that year, but at least it gave us something to be proud of, dog toys and all!
__________________
"Sed res docuit id verum esse, quod in carminibus Appius ait, fabrum esse suae quemque fortunae."
- Every man is the architect of his own fortune.
  #9   Spotlight this post!  
Unread 03-12-2012, 08:36 PM
Billfred's Avatar
Billfred Billfred is offline
Survived year 1–year 2 comes quick!
AKA: @WmLeverette, @GarnetSq, @SCRIW...
FRC #4901 (Garnet Squadron); FLL #???? (Garnet Squadron Alfa)
Team Role: Mentor
 
Join Date: Feb 2004
Rookie Year: 2004
Location: Columbi-YEAH!, SC
Posts: 7,524
Billfred has a reputation beyond reputeBillfred has a reputation beyond reputeBillfred has a reputation beyond reputeBillfred has a reputation beyond reputeBillfred has a reputation beyond reputeBillfred has a reputation beyond reputeBillfred has a reputation beyond reputeBillfred has a reputation beyond reputeBillfred has a reputation beyond reputeBillfred has a reputation beyond reputeBillfred has a reputation beyond repute
Re: polycord and yellow belt

Quote:
Originally Posted by dodar View Post
I'd say ours is the cords walking around on the rollers.
This is the problem we've had this year; we've tried to fix it by limiting the cord's ability to walk.
__________________
William "Billfred" Leverette - Gamecock/Jessica Boucher victim/Facebook-er
Billfred's World Tour: USC Kickoff Palmetto CMP Robot Rodeo Manchester Kickoff Florida Palmetto CMP Capital Clash USC Kickoff FVC Orangeburg Florida Peachtree Palmetto CMP Mission Mayhem Exploding Bacon Vex Event Duel on the Delaware CalGames USC Kickoff Florida Chesapeake Palmetto CMP BattleCry Mission Mayhem Brunswick Eruption 6 Clemson Kickoff Chesapeake Palmetto CMP IRI TNT Greenville Tech Scrimmage Bayou Palmetto CMP IRI GRITS TNT Bayou Palmetto CMP IRI Citadel Kickoff Peachtree Palmetto CMP IRI TNT SCRIW Citadel Kickoff Peachtree Palmetto Championship IRI SCRIW II Chapin Kickoff Palmetto South Florida IRI SCRIW III Chapin Kickoff SC FTC CMP Palmetto SC FLL CMP Orlando CMP Midknight Mayhem SCRIW IV (51,569.9 miles, and still on a mission from Bob)

Rule #1: Do not die. Rule #2: Be respectful. Rule #3: Be safe. Rule #4: Follow the handbook.
  #10   Spotlight this post!  
Unread 03-12-2012, 08:49 PM
MrForbes's Avatar
MrForbes MrForbes is offline
Registered User
AKA: Jim
FRC #1726 (N.E.R.D.S.)
Team Role: Mentor
 
Join Date: Feb 2006
Rookie Year: 2006
Location: Sierra Vista AZ
Posts: 5,051
MrForbes has a reputation beyond reputeMrForbes has a reputation beyond reputeMrForbes has a reputation beyond reputeMrForbes has a reputation beyond reputeMrForbes has a reputation beyond reputeMrForbes has a reputation beyond reputeMrForbes has a reputation beyond reputeMrForbes has a reputation beyond reputeMrForbes has a reputation beyond reputeMrForbes has a reputation beyond reputeMrForbes has a reputation beyond repute
Re: polycord and yellow belt

We first used it this year, it's been working fine for us, no problems. It did take us a little while to figure out how to keep it in place, we figured this out on our prototype and it's been working fine on our robot.

We're using a "comb" to keep the cords in place, at one end. They run on very simple ABS rollers. We used the connectors and hollow cord, and only about 3% stretch.
  #11   Spotlight this post!  
Unread 03-12-2012, 09:19 PM
Billfred's Avatar
Billfred Billfred is offline
Survived year 1–year 2 comes quick!
AKA: @WmLeverette, @GarnetSq, @SCRIW...
FRC #4901 (Garnet Squadron); FLL #???? (Garnet Squadron Alfa)
Team Role: Mentor
 
Join Date: Feb 2004
Rookie Year: 2004
Location: Columbi-YEAH!, SC
Posts: 7,524
Billfred has a reputation beyond reputeBillfred has a reputation beyond reputeBillfred has a reputation beyond reputeBillfred has a reputation beyond reputeBillfred has a reputation beyond reputeBillfred has a reputation beyond reputeBillfred has a reputation beyond reputeBillfred has a reputation beyond reputeBillfred has a reputation beyond reputeBillfred has a reputation beyond reputeBillfred has a reputation beyond repute
Re: polycord and yellow belt

Quote:
Originally Posted by squirrel View Post
We're using a "comb" to keep the cords in place, at one end. They run on very simple ABS rollers. We used the connectors and hollow cord, and only about 3% stretch.
Do you have a photo of this comb? (We used 5% stretch, though our belts are welded.)
__________________
William "Billfred" Leverette - Gamecock/Jessica Boucher victim/Facebook-er
Billfred's World Tour: USC Kickoff Palmetto CMP Robot Rodeo Manchester Kickoff Florida Palmetto CMP Capital Clash USC Kickoff FVC Orangeburg Florida Peachtree Palmetto CMP Mission Mayhem Exploding Bacon Vex Event Duel on the Delaware CalGames USC Kickoff Florida Chesapeake Palmetto CMP BattleCry Mission Mayhem Brunswick Eruption 6 Clemson Kickoff Chesapeake Palmetto CMP IRI TNT Greenville Tech Scrimmage Bayou Palmetto CMP IRI GRITS TNT Bayou Palmetto CMP IRI Citadel Kickoff Peachtree Palmetto CMP IRI TNT SCRIW Citadel Kickoff Peachtree Palmetto Championship IRI SCRIW II Chapin Kickoff Palmetto South Florida IRI SCRIW III Chapin Kickoff SC FTC CMP Palmetto SC FLL CMP Orlando CMP Midknight Mayhem SCRIW IV (51,569.9 miles, and still on a mission from Bob)

Rule #1: Do not die. Rule #2: Be respectful. Rule #3: Be safe. Rule #4: Follow the handbook.
  #12   Spotlight this post!  
Unread 03-12-2012, 09:21 PM
MrForbes's Avatar
MrForbes MrForbes is offline
Registered User
AKA: Jim
FRC #1726 (N.E.R.D.S.)
Team Role: Mentor
 
Join Date: Feb 2006
Rookie Year: 2006
Location: Sierra Vista AZ
Posts: 5,051
MrForbes has a reputation beyond reputeMrForbes has a reputation beyond reputeMrForbes has a reputation beyond reputeMrForbes has a reputation beyond reputeMrForbes has a reputation beyond reputeMrForbes has a reputation beyond reputeMrForbes has a reputation beyond reputeMrForbes has a reputation beyond reputeMrForbes has a reputation beyond reputeMrForbes has a reputation beyond reputeMrForbes has a reputation beyond repute
Re: polycord and yellow belt

sure....I have pics of almost everything!

  #13   Spotlight this post!  
Unread 03-12-2012, 09:32 PM
MattC9 MattC9 is offline
Registered User
no team
Team Role: Alumni
 
Join Date: Nov 2010
Rookie Year: 2009
Location: Texas
Posts: 429
MattC9 has a spectacular aura aboutMattC9 has a spectacular aura aboutMattC9 has a spectacular aura about
Re: polycord and yellow belt

We love our poly cord, we don't have a problem with walking, maybe once or twice at max (were using custom rollers with grooves cut in them) and the welds are strong as can be. We did a test weld to test its strength (put it in a vice and pulled on it) and it was amazing, after 3 students and a mentor pulled on it, all it did was stretch.
  #14   Spotlight this post!  
Unread 03-12-2012, 09:39 PM
FrankJ's Avatar
FrankJ FrankJ is offline
Robot Mentor
FRC #2974 (WALT)
Team Role: Mentor
 
Join Date: Feb 2011
Rookie Year: 2009
Location: Marietta GA
Posts: 829
FrankJ has a reputation beyond reputeFrankJ has a reputation beyond reputeFrankJ has a reputation beyond reputeFrankJ has a reputation beyond reputeFrankJ has a reputation beyond reputeFrankJ has a reputation beyond reputeFrankJ has a reputation beyond reputeFrankJ has a reputation beyond reputeFrankJ has a reputation beyond reputeFrankJ has a reputation beyond reputeFrankJ has a reputation beyond repute
Re: polycord and yellow belt

We are using Squirrel's comb. Except we made it out of 1/16" plexi. Works great.
  #15   Spotlight this post!  
Unread 03-12-2012, 09:41 PM
mathking's Avatar
mathking mathking is offline
Coach/Faculty Advisor
AKA: Greg King
FRC #1014 (Dublin Robotics aka "Bad Robots")
Team Role: Teacher
 
Join Date: Jan 2005
Rookie Year: 1999
Location: Columbus, OH
Posts: 482
mathking has a reputation beyond reputemathking has a reputation beyond reputemathking has a reputation beyond reputemathking has a reputation beyond reputemathking has a reputation beyond reputemathking has a reputation beyond reputemathking has a reputation beyond reputemathking has a reputation beyond reputemathking has a reputation beyond reputemathking has a reputation beyond reputemathking has a reputation beyond repute
Re: polycord and yellow belt

Here is a picture of our "comb" for the belting. It will walk a little if a ball goes through, but it then walks back.
Click image for larger version

Name:	IMG_0412.JPG
Views:	204
Size:	1.78 MB
ID:	12301
__________________
I always tell the kids, when you don't win the Chairman's Award that's not a bad thing. If you think you are deserving, but someone else is better, that means the message of FIRST is really getting out there.
2003 - Buckeye - Rookie All-Star Award
2004 - Pittsburgh - Engineering Inspiration Award
2005 - Pittsburgh - Chairman's Award
2007 - Buckeye - Team Spirit Award
2009 - Buckeye - Chairman's Award, Woodie Flowers Award
2010 - Buckeye - Dean's List Award (Phil Aufdencamp)
2011 - Buckeye - Dean's List Award (Lindesy Fox, Kyle Torrico)
2012 - Queen City - Chairman's Award
2013 - Buckeye - Gracious Professionalism Award, Dean's List Award (Alix Bernier)
2014 - Crossroads - Engineering Inspiration Award
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 08:34 PM.

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


Powered by vBulletin® Version 3.6.4
Copyright ©2000 - 2014, Jelsoft Enterprises Ltd.
Copyright © Chief Delphi