Go to Post It is crucial to keep experience and keeping collected under pressure as high points that can't be measured in a test. - jnelly [more]
Home
Go Back   Chief Delphi > FIRST > General Forum
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 27-05-2013, 15:07
pntbll1313's Avatar
pntbll1313 pntbll1313 is offline
2052 Coach, Build/Electrical Mentor
AKA: Pete
FRC #2052 (KnightKrawler)
Team Role: Mentor
 
Join Date: Dec 2011
Rookie Year: 2007
Location: New Brighton, MN
Posts: 253
pntbll1313 has much to be proud ofpntbll1313 has much to be proud ofpntbll1313 has much to be proud ofpntbll1313 has much to be proud ofpntbll1313 has much to be proud ofpntbll1313 has much to be proud ofpntbll1313 has much to be proud ofpntbll1313 has much to be proud ofpntbll1313 has much to be proud ofpntbll1313 has much to be proud of
Re: Team 2052's Mecanum Showcase!

Quote:
Originally Posted by Siri View Post
I don't see how to make this a 'cancel out' situation: how does it overcome the phenomenon that mecanums break traction before any tank drive with at least the same* CoF and weight? If the issue is slipping (which is why I asked), it's not CoF vs CoF issue; it's the geometry of the wheels. The fact that mecanum CoFs are then 40-75% that of most tanks only serves to compound this.


Roller slip will vary by specific DT, but not nearly as much as between mecanum and tank in general, and it's not helpful in strafing. It's also (thanks to Ether), not overly difficult to model the description, at least to the point of illustrating its negative effect. As the paper explains, the friction that keeps rollers from slipping adversely effects mecanum's strafing traction. If this is what we're talking about, I don't understand the implication that driving the wheels produces more tank-like results.

*Apparently also lower, to a factor of sec(α)--Ether's paper is great.
All very good points! I don't claim to be a physics expert. I am not. That's why I asked Ether to give me some numbers

Again we were never trying to push in the sideways direction. Our video does not show us winning too many big pushing matches. Mecanum allowed us to avoid those situations. We did not choose mecanum for its pushing power haha, nor do we generally use it for such things. The video is just meant to show some examples of how we used mecanum to our benefit this year, and to hopefully show it's not as weak of a drivetrain choice as it is in most CD'ers minds. No one (hopefully) chooses mecanum for traction purposes. We just wanted to highlight some of our match videos because people cited us as a good example of mecanum.
__________________
2016 (mentor/drive-coach)
Quarter-Finalist-Einstein, Winner-Carson Division Champs, Winner-10K Lakes, Chairman's Award-10K Lakes, Finalists-Lake Superior,
Winner-MSHSL Robotics Competition

2015 (mentor/drive-coach)
Finalists-10K Lakes, Finalists-Lake Superior, Finalist-MSHL Robotics Competition, Quarter-Finalist-Galileo Division Champs
2014 (mentor/drive-coach)
Winner-10K Lakes, Winner-Lake Superior Winner-MSHSL Robotics Competition, Quarter-Finalist-Galileo Division Champs
2013 (mentor/drive-coach)
Winner-10K Lakes, Winner-Lake Superior, Winner-MSHSL Robotics Competition, Quarter-Finalist-Newton Division Champs
2012 (mentor/drive-coach)
Finalists-Lake Superior, Semi-Finalist-MSHSL State Championship, Semi-Finalists at 10,000 Lakes
2008-2011 (college mentor)
2007 (driver)
Quarter Finalist-Milwaukee
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


All times are GMT -5. The time now is 00:25.

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