To LUGNET HomepageTo LUGNET News HomepageTo LUGNET Guide Homepage
 Help on Searching
 
Post new message to lugnet.roboticsOpen lugnet.robotics in your NNTP NewsreaderTo LUGNET News Traffic PageSign In (Members)
 Robotics / 767
766  |  768
Subject: 
Re: Worm Drive Question
Newsgroups: 
lugnet.robotics
Date: 
Wed, 25 Nov 1998 16:56:30 GMT
Original-From: 
John Scott Kjellman <jkjellman@ameritech#SayNoToSpam#.net>
Viewed: 
2189 times
  
Just to toss in my three cents (inflation adjusted to 1998 rates ;-)

It seems there are two more options that might be a little easier:

1) My kids have gotten a couple of Lego sets that contain a long square
shaft that has teeth on it.  It mates to a large brick that contains a
small gear attached to a shaft.  If you insert the rod into the brick
and turn the shaft the rod moves in/out (or up/down, depending on its
orientation).  This has a travel of about 8 inches.

2) If you are *really* trying to make an elevator, why not do it the old
fashioned way?  Most older elevators use a couple of pulleys and some
steel cable.  If you were to mount two pulleys on top of your elevator
and two above the ceiling, you would thread some string through the
pulleys onto a spool (made of a couple large pulleys) connected to your
motor.  I say to use multiple pulleys because it acts as a set of
reducing gears, thus increasing strength and reducing speed.  We
wouldn't want your minifigs flying into the ceiling when they get to the
top floor, now would we.

I was thinking about building the same thing (my 4 year old loves Legos
and elevators).  I had planned on approach 2) coupled with a long rod
connected to a touch sensor.  The rod would have wedge shaped bumps at
every floor so that as the elevator passed it would trigger the touch
sensor.  that way you would know what floor you were on.  You could then
use the other inputs for the floor buttons (four floors would be the
maximum without an extremely clever mechanism to allow the reuse of the
third input).

Oh well, enough rambling...

Take care,
KJohn

stephen p spackman wrote:

Matt Sailors wrote:

Sorry I Lost you there, what do you mean by cut Lego?

Tim

I mean cut threads (like on a screw) into the axel using a thread
cutting tool (part of a tap and die set available at most good hardware
stores).  Check out http://www.net-info.com/~dcarlson/ near the bottom
of the page.

Sure, you can do this with puppies, too! Ick, shudder!

("Arthur, Arthur, come quick! Someone's knurled the cat!"
  - hypothetical Monty Python skit)

stephen



Message has 2 Replies:
  Re: Worm Drive Question
 
(...) This is an excellent solution for travel up to 7 inches or so, with a couple of minor drawbacks. 1) This part doesn't seem to be in production any more. I got a few copies, courtesy of Bill Katz, but had to trade away one joint of my little (...) (26 years ago, 28-Nov-98, to lugnet.robotics)
  Elevator alternatives
 
John has an excellent point. Cables make excellent linear-drive systems in Lego projects. I was trying to build a large elevator a while back, and after trying various solutions, I hit upon the following: Use the chain linkbelt as a cable. Insert (...) (25 years ago, 12-Jan-99, to lugnet.robotics)

Message is in Reply To:
  Re: Worm Drive Question
 
(...) Sure, you can do this with puppies, too! Ick, shudder! ("Arthur, Arthur, come quick! Someone's knurled the cat!" - hypothetical Monty Python skit) stephen (26 years ago, 25-Nov-98, to lugnet.robotics)

14 Messages in This Thread:



Entire Thread on One Page:
Nested:  All | Brief | Compact | Dots
Linear:  All | Brief | Compact

This Message and its Replies on One Page:
Nested:  All | Brief | Compact | Dots
Linear:  All | Brief | Compact
    

Custom Search

©2005 LUGNET. All rights reserved. - hosted by steinbruch.info GbR