Go to Post A good thing to do when thinking about designs like this, ask yourself "what do I gain?" - lemiant [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

 
 
 
Thread Tools Rate Thread Display Modes
Prev Previous Post   Next Post Next
  #17   Spotlight this post!  
Unread 27-12-2011, 16:20
Garret's Avatar
Garret Garret is offline
Standing on the Shoulders of Giants
AKA: Garret Smalley
FRC #0691 (Hart District Robotics)
Team Role: Mentor
 
Join Date: Dec 2009
Rookie Year: 2008
Location: Goleta, CA (UCSB)
Posts: 203
Garret has a reputation beyond reputeGarret has a reputation beyond reputeGarret has a reputation beyond reputeGarret has a reputation beyond reputeGarret has a reputation beyond reputeGarret has a reputation beyond reputeGarret has a reputation beyond reputeGarret has a reputation beyond reputeGarret has a reputation beyond reputeGarret has a reputation beyond reputeGarret has a reputation beyond repute
Re: pic: I was bored... so I designed this.

Quote:
1) The keyway would not be compatible with the needle bearings.
2)The counter thrust for the thrust bearing at the wheel would be by the needle bearing housing or the frame member, which is not good. A preloaded pair of angular contact bearings would be better. There is no particular side thrust to keep the thrust bearing loaded.
I did not realize that, but now that I think about that it makes sense. I will change that, I was working on a version that used an angular contact bearing. I have not worked with them before so I wasn't sure how to approach them.

Quote:
3) The gear separating force from the tooth meshing + the torque from the robot weight will be bending the vertical plate. It may be better to continue the removable vertical plate down the the lower shaft, so that the wheel shaft is not cantilevered.
I had a version of this that has that plate extended down to the wheel shaft. On the newest version I have completely removed the cantilever (replaced the modules with our current modules)

Quote:
4) Why is the wheel contact patch offset from the pivot axis? My understanding is that you want to avoid the turning force from a wheel drag moment seen at the pivot. This moment could cause twisting, scuffing, excessive drive resistance and problems with rigging to drive straight.
That is a problem I have fixed that in the newest version.

Thanks for the comments, they have been very helpful.

Here is the newest version so far.
__________________
7 Years of FRC
"You students are at the top of the mountain, at the pinnacle of success, and what is it that you do?
You become the future guides to help others climb the mountain."
Reply With Quote
 


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 06:59.

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