Go to Post IMHO if it was legal a peg leg would be better than a caster. - Edoc'sil [more]
Home
Go Back   Chief Delphi > Technical > Electrical
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 01-02-2016, 10:30
Sauce-ome Sauce-ome is offline
Registered User
FRC #4388 (Ridgebotics)
Team Role: Programmer
 
Join Date: Jan 2015
Rookie Year: 2013
Location: Colorado
Posts: 5
Sauce-ome is an unknown quantity at this point
Inexpensive Slip Ring for Turret

Hello CD!
I'm the programming and electrical lead for team 4388 and we are wanting to create a turret for our robot and we hope to make it turn more than 360 degrees. I have done some research on slip rings that can carry enough current and 8 conductors for motors and signal but have had no luck finding any that aren't very expensive, around the $600 range. If anybody knows any good slip rings I'm open to options and alternative methods.
Thanks!
  #2   Spotlight this post!  
Unread 01-02-2016, 10:54
Sperkowsky's Avatar
Sperkowsky Sperkowsky is online now
Professional Multitasker
AKA: Samuel Perkowsky
FRC #2869 (Regal Eagles)
Team Role: Leadership
 
Join Date: Jan 2015
Rookie Year: 2014
Location: Bethpage, NY
Posts: 1,885
Sperkowsky has a reputation beyond reputeSperkowsky has a reputation beyond reputeSperkowsky has a reputation beyond reputeSperkowsky has a reputation beyond reputeSperkowsky has a reputation beyond reputeSperkowsky has a reputation beyond reputeSperkowsky has a reputation beyond reputeSperkowsky has a reputation beyond reputeSperkowsky has a reputation beyond reputeSperkowsky has a reputation beyond reputeSperkowsky has a reputation beyond repute
It is week 4. A turret is a very complex design element. By the time you get the parts needed to make it, it will be week 5 or 6 and you will probably not finish. Sorry to be so blunt but I've been in that position with an unfinished robot and do not want to see anyone else in they position.
  #3   Spotlight this post!  
Unread 01-02-2016, 11:02
RyanShoff RyanShoff is offline
Registered User
FRC #4143 (Mars Wars)
Team Role: Mentor
 
Join Date: Mar 2012
Rookie Year: 2012
Location: Metamora, IL
Posts: 145
RyanShoff is a splendid one to beholdRyanShoff is a splendid one to beholdRyanShoff is a splendid one to beholdRyanShoff is a splendid one to beholdRyanShoff is a splendid one to beholdRyanShoff is a splendid one to behold
Re: Inexpensive Slip Ring for Turret

We used these last season:

http://www.ebay.com/itm/LARGE-CURREN...item19f8151b35

Not quite what you wanted, but close.
__________________
Ryan Shoff
4143 Mars/Wars
CheapGears.com
  #4   Spotlight this post!  
Unread 01-02-2016, 11:25
Andrew Schreiber Andrew Schreiber is offline
Data Nerd
FRC #0079
 
Join Date: Jan 2005
Rookie Year: 2000
Location: Misplaced Michigander
Posts: 4,057
Andrew Schreiber has a reputation beyond reputeAndrew Schreiber has a reputation beyond reputeAndrew Schreiber has a reputation beyond reputeAndrew Schreiber has a reputation beyond reputeAndrew Schreiber has a reputation beyond reputeAndrew Schreiber has a reputation beyond reputeAndrew Schreiber has a reputation beyond reputeAndrew Schreiber has a reputation beyond reputeAndrew Schreiber has a reputation beyond reputeAndrew Schreiber has a reputation beyond reputeAndrew Schreiber has a reputation beyond repute
Re: Inexpensive Slip Ring for Turret

a) Turrets are complicated, do you REALLY need it.

b) Turrets without slip rings are fairly common. You just have to have extra wire to wrap. You won't have infinite travel but you can do more than 360.

c) Slip rings with those criteria ARE expensive. I've got some that can handle one motor that's pretty cheap. Much past that... yeah nope.
__________________




.
  #5   Spotlight this post!  
Unread 01-02-2016, 11:27
Rosiebotboss's Avatar
Rosiebotboss Rosiebotboss is offline
2015-16 Divisional LRI - Archimedes
AKA: Dana P. Henry
FRC #0839 (Rosie Robotics)
Team Role: Mentor
 
Join Date: Nov 2002
Rookie Year: 2002
Location: Agawam, MA
Posts: 853
Rosiebotboss has a reputation beyond reputeRosiebotboss has a reputation beyond reputeRosiebotboss has a reputation beyond reputeRosiebotboss has a reputation beyond reputeRosiebotboss has a reputation beyond reputeRosiebotboss has a reputation beyond reputeRosiebotboss has a reputation beyond reputeRosiebotboss has a reputation beyond reputeRosiebotboss has a reputation beyond reputeRosiebotboss has a reputation beyond reputeRosiebotboss has a reputation beyond repute
Send a message via AIM to Rosiebotboss
Re: Inexpensive Slip Ring for Turret

Schedule aside, please reread R9 (specifically H. in the blue box) and R11.

Many slip rings contain mercury.
__________________
Co-Founder/Mentor FRC Team 839 / JrFLL Team 137/Rosie Robotics/Agawam HS
Winner NEF District WPI 2016
Regional CA-08 Boston, 12 WPI, Eng'g Excellence, 12-15 UL Safety, 15 Motorola Quality
KPCB Entrepreneurship 04, 05, 06, 07, 10, 11, 13, 14, 15, 16
Rookie All Star and Top Rookie Seed 2002
Paul Harris Fellow, CMP Inspector 05-16, Head LRI NE FIRST JTB 1944-2008 "What did you do with your dash?"
  #6   Spotlight this post!  
Unread 01-02-2016, 11:33
GeeTwo's Avatar
GeeTwo GeeTwo is offline
Technical Director
AKA: Gus Michel II
FRC #3946 (Tiger Robotics)
Team Role: Mentor
 
Join Date: Jan 2014
Rookie Year: 2013
Location: Slidell, LA
Posts: 3,570
GeeTwo has a reputation beyond reputeGeeTwo has a reputation beyond reputeGeeTwo has a reputation beyond reputeGeeTwo has a reputation beyond reputeGeeTwo has a reputation beyond reputeGeeTwo has a reputation beyond reputeGeeTwo has a reputation beyond reputeGeeTwo has a reputation beyond reputeGeeTwo has a reputation beyond reputeGeeTwo has a reputation beyond reputeGeeTwo has a reputation beyond repute
Re: Inexpensive Slip Ring for Turret

Quote:
Originally Posted by RyanShoff View Post
We used these last season:

http://www.ebay.com/itm/LARGE-CURREN...item19f8151b35

Not quite what you wanted, but close.
Six wires should be enough for two motors with feedback, if you can get enough power through two 30A breakers. Put two Talon SRXs on the turret. Run power for them and one CAN pair. Terminate the CAN bus on the turret so you don't need it to return. Then wire sensors to the SRX inputs. You have four limit switches and at least two encoders or analog sensors you can connect, getting all that info back and forth through two wires.
__________________

If you can't find time to do it right, how are you going to find time to do it over?
If you don't pass it on, it never happened.
Robots are great, but inspiration is the reason we're here.
Friends don't let friends use master links.
  #7   Spotlight this post!  
Unread 01-02-2016, 11:37
Andrew Schreiber Andrew Schreiber is offline
Data Nerd
FRC #0079
 
Join Date: Jan 2005
Rookie Year: 2000
Location: Misplaced Michigander
Posts: 4,057
Andrew Schreiber has a reputation beyond reputeAndrew Schreiber has a reputation beyond reputeAndrew Schreiber has a reputation beyond reputeAndrew Schreiber has a reputation beyond reputeAndrew Schreiber has a reputation beyond reputeAndrew Schreiber has a reputation beyond reputeAndrew Schreiber has a reputation beyond reputeAndrew Schreiber has a reputation beyond reputeAndrew Schreiber has a reputation beyond reputeAndrew Schreiber has a reputation beyond reputeAndrew Schreiber has a reputation beyond repute
Re: Inexpensive Slip Ring for Turret

Quote:
Originally Posted by GeeTwo View Post
Six wires should be enough for two motors with feedback, if you can get enough power through two 30A breakers. Put two Talon SRXs on the turret. Run power for them and one CAN pair. Terminate the CAN bus on the turret so you don't need it to return. Then wire sensors to the SRX inputs. You have four limit switches and at least two encoders or analog sensors you can connect, getting all that info back and forth through two wires.
Are you certain that the implementation of CAN used on the RoboRIO will operate in a noisy environment like that? I know that some implementations are capable of that but I don't know the details behind ours (or those implementations). From what I understood the more noise you deal with the less speed the bus operates with.
__________________




.
  #8   Spotlight this post!  
Unread 01-02-2016, 11:48
Jon Stratis's Avatar
Jon Stratis Jon Stratis is online now
Electrical/Programming Mentor
FRC #2177 (The Robettes)
Team Role: Mentor
 
Join Date: Feb 2007
Rookie Year: 2006
Location: Minnesota
Posts: 3,736
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: Inexpensive Slip Ring for Turret

Personally, I would question the requirement for unlimited rotation. You don't need something that can do absolutely everything in every situation. If you can reduce complexity by building to just 90% of anticipated situations, then I'd do that and give yourself more time for debugging and driver practice.
__________________
2007 - Present: Mentor, 2177 The Robettes
LRI: North Star 2012-2016; Lake Superior 2013-2014; MN State Tournament 2013-2014, 2016; Galileo 2016; Iowa 2017
2015: North Star Regional Volunteer of the Year
2016: Lake Superior WFFA
  #9   Spotlight this post!  
Unread 01-02-2016, 11:56
jvriezen jvriezen is offline
Registered User
FRC #3184 (Burnsville Blaze)
Team Role: Mentor
 
Join Date: Jan 2010
Rookie Year: 2008
Location: Burnsville, MN
Posts: 635
jvriezen has a reputation beyond reputejvriezen has a reputation beyond reputejvriezen has a reputation beyond reputejvriezen has a reputation beyond reputejvriezen has a reputation beyond reputejvriezen has a reputation beyond reputejvriezen has a reputation beyond reputejvriezen has a reputation beyond reputejvriezen has a reputation beyond reputejvriezen has a reputation beyond reputejvriezen has a reputation beyond repute
Re: Inexpensive Slip Ring for Turret

I would agree with Jon. In 2012, my team (at the time) had far more range than we ever used on the turret. The fact is, you can rotate your robot with its drive train to get close to where you want to aim, then use a finer grained adjustment on a turret to do final alignment. Will save a lot of time and your drivers will do this anyway, even if you have >360 deg rotation on the turret. So a lazy susan with a cable tether is likely the right solution here, IMO.
__________________
John Vriezen
FRC, Mentor, Inspector #3184 2016- #4859 2015, #2530 2010-2014 FTC Mentor, Inspector #7152 2013-14
  #10   Spotlight this post!  
Unread 01-02-2016, 12:24
Sauce-ome Sauce-ome is offline
Registered User
FRC #4388 (Ridgebotics)
Team Role: Programmer
 
Join Date: Jan 2015
Rookie Year: 2013
Location: Colorado
Posts: 5
Sauce-ome is an unknown quantity at this point
Re: Inexpensive Slip Ring for Turret

Thanks for the feedback. Thinking about it now it does seem overkill but it still might be something good to test in the future to see if the CAN bus would work with that much noise along with the amount of current needed to run motors.
  #11   Spotlight this post!  
Unread 03-02-2016, 08:09
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: 10,766
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: Inexpensive Slip Ring for Turret

Sauce,
You can redesign the position of your controllers so that you don't have to pass CAN through the turret. this should reduce your wire needs. You can also parallel lower current contacts to increase the amount of current you can pass to the turret.
I agree with others, that for this game, continuous 360 degree freedom is not needed. You can easily get 500 degrees of rotation without the need for a slip ring design.
__________________
Good Luck All. Learn something new, everyday!
Al
WB9UVJ
www.wildstang.org
________________________
Storming the Tower since 1996.
  #12   Spotlight this post!  
Unread 03-02-2016, 08:15
346CADmen's Avatar
346CADmen 346CADmen is offline
Registered User
FRC #0346
Team Role: Mentor
 
Join Date: Jan 2014
Rookie Year: 2013
Location: Virginia
Posts: 93
346CADmen is a splendid one to behold346CADmen is a splendid one to behold346CADmen is a splendid one to behold346CADmen is a splendid one to behold346CADmen is a splendid one to behold346CADmen is a splendid one to behold346CADmen is a splendid one to behold
Re: Inexpensive Slip Ring for Turret

Only because you asked. The Mercotac models are small and versatile. But I too think this (revolving turret) might be overkill for this game.
  #13   Spotlight this post!  
Unread 03-02-2016, 08:17
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: 10,766
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: Inexpensive Slip Ring for Turret

Mercotac received that name because they contain mercury. They are not legal for FRC robots.
__________________
Good Luck All. Learn something new, everyday!
Al
WB9UVJ
www.wildstang.org
________________________
Storming the Tower since 1996.
  #14   Spotlight this post!  
Unread 05-02-2016, 08:34
Dale(294engr]'s Avatar
Dale(294engr] Dale(294engr] is offline
Mentor/Sponsor since '98
FRC #0294 (Beach Cities Robotics)
Team Role: Engineer
 
Join Date: Jan 2004
Rookie Year: 1998
Location: Redondo Beach, CA
Posts: 92
Dale(294engr] is a glorious beacon of lightDale(294engr] is a glorious beacon of lightDale(294engr] is a glorious beacon of lightDale(294engr] is a glorious beacon of lightDale(294engr] is a glorious beacon of lightDale(294engr] is a glorious beacon of light
Re: Inexpensive Slip Ring for Turret

Quote:
Originally Posted by Sauce-ome View Post
Hello CD!
I'm the programming and electrical lead for team 4388 and we are wanting to create a turret for our robot and we hope to make it turn more than 360 degrees. I have done some research on slip rings that can carry enough current and 8 conductors for motors and signal but have had no luck finding any that aren't very expensive, around the $600 range. If anybody knows any good slip rings I'm open to options and alternative methods.
Thanks!
Here is a $16 possibility, 24 rings, parallel some for higher currents
Az:
http://www.goldmine-elec-products.co...?number=G20822
Rare and unique Senring SNMO12A-24-1 24 conductor slipring made for data, video, rotating stage lights. Consists of a fixed component and a rotating component for conducting signals and power to a rotating item (360 degrees). This model is for up to 24 wires and is rated for up to 250 RPM. Rated for 2AMP maximum per ring. Maximum voltage is 210VDC or 240VAC. Size 15.5mm dia. X 39mm (L). These are extensively used in CCTV pan/tilt camera mounts, electrical test equipment, stage lights robotics and medical equipment.
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 23:43.

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