Go to Post There is beauty in pure simplicity. - artdutra04 [more]
Home
Go Back   Chief Delphi > ChiefDelphi.com Website > Extra Discussion
CD-Media   CD-Spy  
portal register members calendar search Today's Posts Mark Forums Read FAQ rules

 
Reply
Thread Tools Rate Thread Display Modes
  #1   Spotlight this post!  
Unread 09-05-2010, 23:17
548swimmer's Avatar
548swimmer 548swimmer is offline
CAD Leader
AKA: Alec Wagner
FRC #0548 (Robostangs)
Team Role: CAD
 
Join Date: Apr 2010
Rookie Year: 2005
Location: Michigan
Posts: 299
548swimmer has much to be proud of548swimmer has much to be proud of548swimmer has much to be proud of548swimmer has much to be proud of548swimmer has much to be proud of548swimmer has much to be proud of548swimmer has much to be proud of548swimmer has much to be proud of
pic: prototype drivetrain v2.1

Reply With Quote
  #2   Spotlight this post!  
Unread 09-05-2010, 23:18
548swimmer's Avatar
548swimmer 548swimmer is offline
CAD Leader
AKA: Alec Wagner
FRC #0548 (Robostangs)
Team Role: CAD
 
Join Date: Apr 2010
Rookie Year: 2005
Location: Michigan
Posts: 299
548swimmer has much to be proud of548swimmer has much to be proud of548swimmer has much to be proud of548swimmer has much to be proud of548swimmer has much to be proud of548swimmer has much to be proud of548swimmer has much to be proud of548swimmer has much to be proud of
Re: pic: prototype drivetrain v2.1

Any comments?
Should the bushings be brass or nylon?
__________________
My religion is physics, it can explain everything.

WINNER -- 2011 Waterford District
District Chairman's -- 2011 Waterford District
Finalist -- 2011 Ann Arbor District
State Chairman's -- 2011 Michigan State Championship
Quarter-finalist -- 2011 Galileo
2011 Championship -- Highest Ranking Score
Reply With Quote
  #3   Spotlight this post!  
Unread 10-05-2010, 00:49
CraigHickman
 
Posts: n/a
Re: pic: prototype drivetrain v2.1

This drive design does not need suspension.
Reply With Quote
  #4   Spotlight this post!  
Unread 10-05-2010, 00:59
548swimmer's Avatar
548swimmer 548swimmer is offline
CAD Leader
AKA: Alec Wagner
FRC #0548 (Robostangs)
Team Role: CAD
 
Join Date: Apr 2010
Rookie Year: 2005
Location: Michigan
Posts: 299
548swimmer has much to be proud of548swimmer has much to be proud of548swimmer has much to be proud of548swimmer has much to be proud of548swimmer has much to be proud of548swimmer has much to be proud of548swimmer has much to be proud of548swimmer has much to be proud of
Re: pic: prototype drivetrain v2.1

Quote:
Originally Posted by CraigHickman View Post
This drive design does not need suspension.
Why not? It is incorporated as an innovative element in case it becomes necessary in the future. It is possible this system will never be built.
__________________
My religion is physics, it can explain everything.

WINNER -- 2011 Waterford District
District Chairman's -- 2011 Waterford District
Finalist -- 2011 Ann Arbor District
State Chairman's -- 2011 Michigan State Championship
Quarter-finalist -- 2011 Galileo
2011 Championship -- Highest Ranking Score
Reply With Quote
  #5   Spotlight this post!  
Unread 10-05-2010, 04:33
Greg Needel's Avatar Unsung FIRST Hero
Greg Needel Greg Needel is offline
REVving up for a new season
FRC #2848 (All-sparks)
Team Role: Engineer
 
Join Date: Jan 2002
Rookie Year: 2002
Location: Dallas, TX
Posts: 3,110
Greg Needel has a reputation beyond reputeGreg Needel has a reputation beyond reputeGreg Needel has a reputation beyond reputeGreg Needel has a reputation beyond reputeGreg Needel has a reputation beyond reputeGreg Needel has a reputation beyond reputeGreg Needel has a reputation beyond reputeGreg Needel has a reputation beyond reputeGreg Needel has a reputation beyond reputeGreg Needel has a reputation beyond reputeGreg Needel has a reputation beyond repute
Re: pic: prototype drivetrain v2.1

I am not sure if this is what you are trying to convey in your above image so if not consider this. Using your pivot shaft as a jack shaft will enable the chains to freely rotate and stay tensioned throughout the range of suspension. You can determine the center distances for chain runs with an even number of links and then do not require external tensioners. Here is even an calculator to do it for you. http://www.botlanta.org/converters/d.../sprocket.html

As for if this drive needs a suspension or not totally depends on your team and it's engineering decisions regarding the application for this drive. Keep thinking outside of the box it will serve you well in the future.







Quote:
Originally Posted by CraigHickman View Post
This drive design does not need suspension.
There are no absolutes in engineering decisions. People and organizations value different things and out of context it would be wrong to make assumptions on the necessity of a feature.
__________________
Greg Needel│www.robogreg.com
Co-founder REV Robotics LLC www.REVrobotics.com
2014 FRC World Champions with 254, 469, & 74

Last edited by Greg Needel : 10-05-2010 at 04:37.
Reply With Quote
  #6   Spotlight this post!  
Unread 10-05-2010, 05:20
Hawiian Cadder's Avatar
Hawiian Cadder Hawiian Cadder is offline
Registered User
AKA: Isaak
FRC #0159 (Alpine Robotics)
Team Role: CAD
 
Join Date: Feb 2010
Rookie Year: 2003
Location: Fort Colins Colorado
Posts: 573
Hawiian Cadder is a name known to allHawiian Cadder is a name known to allHawiian Cadder is a name known to allHawiian Cadder is a name known to allHawiian Cadder is a name known to allHawiian Cadder is a name known to all
Re: pic: prototype drivetrain v2.1

last year we did the same type of thing with our prototype, we had a delrin tube tensioned with a zip tie, the tubes 1/4 inch thick wall was completely destroyed by the chain in about 15 min, if you do that, you are going to need some large diameter nylon.
Reply With Quote
  #7   Spotlight this post!  
Unread 10-05-2010, 09:17
JamesCH95's Avatar
JamesCH95 JamesCH95 is offline
Hardcore Dork
AKA: JCH
FRC #0095 (The Grasshoppers)
Team Role: Engineer
 
Join Date: Dec 2004
Rookie Year: 2001
Location: Enfield, NH
Posts: 1,885
JamesCH95 has a reputation beyond reputeJamesCH95 has a reputation beyond reputeJamesCH95 has a reputation beyond reputeJamesCH95 has a reputation beyond reputeJamesCH95 has a reputation beyond reputeJamesCH95 has a reputation beyond reputeJamesCH95 has a reputation beyond reputeJamesCH95 has a reputation beyond reputeJamesCH95 has a reputation beyond reputeJamesCH95 has a reputation beyond reputeJamesCH95 has a reputation beyond repute
Re: pic: prototype drivetrain v2.1

Quote:
Originally Posted by 548swimmer View Post
Any comments?
Should the bushings be brass or nylon?
your chain bearings could be nylon, depending on how hard they push against the chain. Nylon will be better than delrin or teflon in terms of wear. Brass could work too, but it might be excessively loud. You could use two idler sprockets and not have to worry about anything.
__________________
Theory is a nice place, I'd like to go there one day, I hear everything works there.

Maturity is knowing you were an idiot, common sense is trying to not be an idiot, wisdom is knowing that you will still be an idiot.
Reply With Quote
  #8   Spotlight this post!  
Unread 10-05-2010, 10:59
548swimmer's Avatar
548swimmer 548swimmer is offline
CAD Leader
AKA: Alec Wagner
FRC #0548 (Robostangs)
Team Role: CAD
 
Join Date: Apr 2010
Rookie Year: 2005
Location: Michigan
Posts: 299
548swimmer has much to be proud of548swimmer has much to be proud of548swimmer has much to be proud of548swimmer has much to be proud of548swimmer has much to be proud of548swimmer has much to be proud of548swimmer has much to be proud of548swimmer has much to be proud of
Re: pic: prototype drivetrain v2.1

Quote:
Originally Posted by Greg Needel View Post
I am not sure if this is what you are trying to convey in your above image so if not consider this. Using your pivot shaft as a jack shaft will enable the chains to freely rotate and stay tensioned throughout the range of suspension. You can determine the center distances for chain runs with an even number of links and then do not require external tensioners. Here is even an calculator to do it for you. http://www.botlanta.org/converters/d.../sprocket.html

As for if this drive needs a suspension or not totally depends on your team and it's engineering decisions regarding the application for this drive. Keep thinking outside of the box it will serve you well in the future.









There are no absolutes in engineering decisions. People and organizations value different things and out of context it would be wrong to make assumptions on the necessity of a feature.
Thank you very much for your feedback!

The goal was to show how I intend to keep the chain under tension while it is pivoting. The nylon spacers are adjustable so that they can act as chain tensioners. When the carriage moves up and down, the tensioners will as well, theoretically keeping the chain under tension. If any one knows whether or not this will work, please let me know.

The bushing question was in reference to the bushings on the carriage that are currently brass. I guess a better way to phrase it would be to ask whether brass or nylon has a lower coefficient of friction with aluminum.
__________________
My religion is physics, it can explain everything.

WINNER -- 2011 Waterford District
District Chairman's -- 2011 Waterford District
Finalist -- 2011 Ann Arbor District
State Chairman's -- 2011 Michigan State Championship
Quarter-finalist -- 2011 Galileo
2011 Championship -- Highest Ranking Score
Reply With Quote
  #9   Spotlight this post!  
Unread 10-05-2010, 13:06
JamesCH95's Avatar
JamesCH95 JamesCH95 is offline
Hardcore Dork
AKA: JCH
FRC #0095 (The Grasshoppers)
Team Role: Engineer
 
Join Date: Dec 2004
Rookie Year: 2001
Location: Enfield, NH
Posts: 1,885
JamesCH95 has a reputation beyond reputeJamesCH95 has a reputation beyond reputeJamesCH95 has a reputation beyond reputeJamesCH95 has a reputation beyond reputeJamesCH95 has a reputation beyond reputeJamesCH95 has a reputation beyond reputeJamesCH95 has a reputation beyond reputeJamesCH95 has a reputation beyond reputeJamesCH95 has a reputation beyond reputeJamesCH95 has a reputation beyond reputeJamesCH95 has a reputation beyond repute
Re: pic: prototype drivetrain v2.1

The solid/plain surface bearings (which are different from bushings) that the suspension pivots on could be made from brass, with a ground steel shoulder bolt being used as a shaft, which would be very strong and durable. Better yet they could both be purchased parts. If the shaft is aluminum I would use a nylon or delrin bearing so that the bearing wears faster than the shaft.
__________________
Theory is a nice place, I'd like to go there one day, I hear everything works there.

Maturity is knowing you were an idiot, common sense is trying to not be an idiot, wisdom is knowing that you will still be an idiot.
Reply With Quote
  #10   Spotlight this post!  
Unread 10-05-2010, 15:03
548swimmer's Avatar
548swimmer 548swimmer is offline
CAD Leader
AKA: Alec Wagner
FRC #0548 (Robostangs)
Team Role: CAD
 
Join Date: Apr 2010
Rookie Year: 2005
Location: Michigan
Posts: 299
548swimmer has much to be proud of548swimmer has much to be proud of548swimmer has much to be proud of548swimmer has much to be proud of548swimmer has much to be proud of548swimmer has much to be proud of548swimmer has much to be proud of548swimmer has much to be proud of
Re: pic: prototype drivetrain v2.1

Quote:
Originally Posted by JamesCH95 View Post
The solid/plain surface bearings (which are different from bushings) that the suspension pivots on could be made from brass, with a ground steel shoulder bolt being used as a shaft, which would be very strong and durable. Better yet they could both be purchased parts. If the shaft is aluminum I would use a nylon or delrin bearing so that the bearing wears faster than the shaft.
We like doing all of our own fab work, so I'll swith the material to nylon. Thanks for the help!
__________________
My religion is physics, it can explain everything.

WINNER -- 2011 Waterford District
District Chairman's -- 2011 Waterford District
Finalist -- 2011 Ann Arbor District
State Chairman's -- 2011 Michigan State Championship
Quarter-finalist -- 2011 Galileo
2011 Championship -- Highest Ranking Score
Reply With Quote
  #11   Spotlight this post!  
Unread 10-05-2010, 17:10
JamesCH95's Avatar
JamesCH95 JamesCH95 is offline
Hardcore Dork
AKA: JCH
FRC #0095 (The Grasshoppers)
Team Role: Engineer
 
Join Date: Dec 2004
Rookie Year: 2001
Location: Enfield, NH
Posts: 1,885
JamesCH95 has a reputation beyond reputeJamesCH95 has a reputation beyond reputeJamesCH95 has a reputation beyond reputeJamesCH95 has a reputation beyond reputeJamesCH95 has a reputation beyond reputeJamesCH95 has a reputation beyond reputeJamesCH95 has a reputation beyond reputeJamesCH95 has a reputation beyond reputeJamesCH95 has a reputation beyond reputeJamesCH95 has a reputation beyond reputeJamesCH95 has a reputation beyond repute
Re: pic: prototype drivetrain v2.1

Good deal. Look at 7075 or 2024 for the axle, with a good lathe you'll be able to get an excellent surface finish and great strength. I don't know if you have one, but a HSS reamer to do the inside of any polymer bearing is much much much easier/faster/idiot proof than boring it out.
__________________
Theory is a nice place, I'd like to go there one day, I hear everything works there.

Maturity is knowing you were an idiot, common sense is trying to not be an idiot, wisdom is knowing that you will still be an idiot.
Reply With Quote
  #12   Spotlight this post!  
Unread 10-05-2010, 17:25
548swimmer's Avatar
548swimmer 548swimmer is offline
CAD Leader
AKA: Alec Wagner
FRC #0548 (Robostangs)
Team Role: CAD
 
Join Date: Apr 2010
Rookie Year: 2005
Location: Michigan
Posts: 299
548swimmer has much to be proud of548swimmer has much to be proud of548swimmer has much to be proud of548swimmer has much to be proud of548swimmer has much to be proud of548swimmer has much to be proud of548swimmer has much to be proud of548swimmer has much to be proud of
Re: pic: prototype drivetrain v2.1

Quote:
Originally Posted by JamesCH95 View Post
Good deal. Look at 7075 or 2024 for the axle, with a good lathe you'll be able to get an excellent surface finish and great strength. I don't know if you have one, but a HSS reamer to do the inside of any polymer bearing is much much much easier/faster/idiot proof than boring it out.
We usually just drill it out on a lathe, and all of our machining is very high quality because we have access to the Milford Proving Grounds machine shop. I guess we could ream it, but it's unlikely anyone will remember to do that by the time this gets made, if it even does, in September/ this summer.
__________________
My religion is physics, it can explain everything.

WINNER -- 2011 Waterford District
District Chairman's -- 2011 Waterford District
Finalist -- 2011 Ann Arbor District
State Chairman's -- 2011 Michigan State Championship
Quarter-finalist -- 2011 Galileo
2011 Championship -- Highest Ranking Score
Reply With Quote
  #13   Spotlight this post!  
Unread 10-05-2010, 18:59
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: 5,525
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: pic: prototype drivetrain v2.1

Quote:
Originally Posted by 548swimmer View Post
We usually just drill it out on a lathe, and all of our machining is very high quality because we have access to the Milford Proving Grounds machine shop. I guess we could ream it, but it's unlikely anyone will remember to do that by the time this gets made, if it even does, in September/ this summer.
Reaming doesn't really take much longer than drilling, I don't see any reason not to do it.
Reply With Quote
  #14   Spotlight this post!  
Unread 10-05-2010, 19:03
548swimmer's Avatar
548swimmer 548swimmer is offline
CAD Leader
AKA: Alec Wagner
FRC #0548 (Robostangs)
Team Role: CAD
 
Join Date: Apr 2010
Rookie Year: 2005
Location: Michigan
Posts: 299
548swimmer has much to be proud of548swimmer has much to be proud of548swimmer has much to be proud of548swimmer has much to be proud of548swimmer has much to be proud of548swimmer has much to be proud of548swimmer has much to be proud of548swimmer has much to be proud of
Re: pic: prototype drivetrain v2.1

Quote:
Originally Posted by AdamHeard View Post
Reaming doesn't really take much longer than drilling, I don't see any reason not to do it.
Remembering. Many of the build team members are so used to working in our school's "shop" where we have no reamers, that when we are in a real shop, we just go straight for the drill bits because we're used to them. If we remember to ream, there is no reason for us not to.
__________________
My religion is physics, it can explain everything.

WINNER -- 2011 Waterford District
District Chairman's -- 2011 Waterford District
Finalist -- 2011 Ann Arbor District
State Chairman's -- 2011 Michigan State Championship
Quarter-finalist -- 2011 Galileo
2011 Championship -- Highest Ranking Score
Reply With Quote
  #15   Spotlight this post!  
Unread 10-05-2010, 19:07
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: 5,525
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: pic: prototype drivetrain v2.1

Quote:
Originally Posted by 548swimmer View Post
Remembering. Many of the build team members are so used to working in our school's "shop" where we have no reamers, that when we are in a real shop, we just go straight for the drill bits because we're used to them. If we remember to ream, there is no reason for us not to.
We work in our school's shop as well, and purchased the few sizes of reamers we routinely use; they were inexpensive and well worth it.
Reply With Quote
Reply


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
pic: Prototype Drivetrain v2 548swimmer Extra Discussion 47 11-05-2010 01:13
pic: Prototype Drivetrain 548swimmer Extra Discussion 38 09-05-2010 21:14
pic: 499 Prototype drivetrain final layout Andrew Schuetze Extra Discussion 9 01-01-2008 21:37
pic: A drivetrain prototype idea GMAdan Extra Discussion 16 24-04-2007 16:14
1541 Prototype Drivetrain bombadier337 Technical Discussion 12 23-01-2006 08:26


All times are GMT -5. The time now is 02:34.

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