Go to Post Of course I'm not an admin, so this opinion is worth about as much as a disco record or AOL Free Trail CD. - PayneTrain [more]
Home
Go Back   Chief Delphi > Technical > Technical 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 14-12-2012, 13:04
Wayne TenBrink's Avatar
Wayne TenBrink Wayne TenBrink is offline
<< (2008 Game Piece)
FRC #1918 (NC Gears)
Team Role: Engineer
 
Join Date: Apr 2007
Rookie Year: 2006
Location: Fremont, MI, USA
Posts: 528
Wayne TenBrink has a reputation beyond reputeWayne TenBrink has a reputation beyond reputeWayne TenBrink has a reputation beyond reputeWayne TenBrink has a reputation beyond reputeWayne TenBrink has a reputation beyond reputeWayne TenBrink has a reputation beyond reputeWayne TenBrink has a reputation beyond reputeWayne TenBrink has a reputation beyond reputeWayne TenBrink has a reputation beyond reputeWayne TenBrink has a reputation beyond reputeWayne TenBrink has a reputation beyond repute
Re: Elevators: Cascaded vs Continuous

Quote:
Originally Posted by jspatz1 View Post
My aging brain is not visualizing this, perhaps you could sketch it. The purpose of a return/take-up cable is to drive the elevator down as well as up. You could create a closed loop cable between the 2nd and 3rd stage, but it would not drive the 3rd stage. Remember that the lift cable for the 3rd stage is anchored to the 1st stage, not the 2nd. It therefore needs a corresponding return cable which is also based on the 1st stage (the 2X take-up). It is a closed loop overall, but not between stages.
We solved the 2X take-up issue by making our winch drum a 2-stage drum (photo) with the return stage 2X diameter of the payout stage. Made the cable rigging quite simple.
Each moving stage acts as a closed loop, but the linkage involves the two stages before it. For example, the cable (belt, chain, etc.) would be anchored to stage 3, run over pulleys at each end of stage 2, and be anchored to stage 1. The stage 2 cable would be anchored to stage 2, run over pulleys on stage 1, and be anchored to the non-moving chassis/frame. The stage 1 cable would be anchored on stage 1, run over pulleys on the chassis/frame, and be anchored/attached to the drive drum. The ends of each cable terminate at one anchor point which includes the tensioning adjustment. The other anchor point for each cable is normally a clamp restraint on a continuous section of the cable. When loosened, it allows for adjustment of the location of that stage relative to the other stages. It doesn't matter which of the stages the different anchor points are on.

We have used both methods (continuous and cascading). Both work fine if done well, and both stink if done poorly. My advice is to use a design that allows for easy access to cable tension adjustment and replacement, and make it so that the cable cannot come off the pulleys when tension is lost.
__________________
NC Gears (Newaygo County Geeks Engineering Awesome Robotic Solutions)

FRC 1918 (Competing at St. Joseph and West MI in 2017)
FTC 6043 & 7911

Last edited by Wayne TenBrink : 14-12-2012 at 13:09.
 


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 00:28.

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