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 / 9781
9780  |  9782
Subject: 
RE: Design Problem
Newsgroups: 
lugnet.robotics
Date: 
Thu, 6 Jan 2000 20:04:49 GMT
Original-From: 
Tilman Sporkert <TILMAN@ACTIVESWstopspammers.COM>
Viewed: 
495 times
  
The drop zone ride in the Great America ride across the street uses magnetic
effects, without mechanic contact. Not reproducible with Lego...

Braking the fall directly is probably not easy. I'd look into intalling
something on the lower part of the pylon (the braking section) that engages with
a rotating part in the dropping ride. In the upper part (the free fall section),
it doesn't engage, and doesn't interfere with the free fall. Brake by putting
resistance onto the rotation. You could do this with a clutch gear on a fixed
axle, rubber bands and pulleys on another axle that can't turn, or use a
short-circuited motor: use a short wire, with both ends connected to the motor.
Experiment with rotating the second connector until you find a connection that
makes it hard to turn the motor. You have wide control over the braking force
through gearing.

Engagment could be with a gear rack that's mounted on the side of the pylon. Or
use wheels with tires and make the pylon fatter at the bottom so that the wheels
don't touch at the upper part.

With the RCX, you could get a little more sophisticated, and add a rototation
sensor. Let the motor float during the fall and first engagment. This requires
NQC or something similar - you can't put a motor output of the RCX into floating
mode with the Lego programming environment. Once the  motor spins up, put it
into braking mode. Check the position through the touch sensor, and let it float
a little more if it stops to quickly. This of course isn't very failsafe. If the
RCX looses power, your gondola will simply crash without any braking effects.

This sounds like a lot of fun!

Tilman

-----Original Message-----
From: news-gateway@lugnet.com [mailto:news-gateway@lugnet.com]On Behalf
Of Charlie Young
Sent: Thursday, January 06, 2000 11:28 AM
To: lego-robotics@crynwr.com
Subject: Design Problem


  Its a Drop Zone amusement ride. The cars are pulled up to the top and
then they fall down.  Ive used magnets to attach the cars to the lifter
but i cant figure out how to brake the cars.  I dont have any pictures
up yet.





Message has 1 Reply:
  Re: Design Problem
 
Take the bent beams and attach them to a motor. When the car is at the top, the motor turns the beams, and the beams push the car off the magnets. To stop the car, you can have 2 sets of repulsing magnets - one on the car, and another on the bottom. (...) (25 years ago, 6-Jan-00, to lugnet.robotics)

Message is in Reply To:
  Design Problem
 
Its a Drop Zone amusement ride. The cars are pulled up to the top and then they fall down. Ive used magnets to attach the cars to the lifter but i cant figure out how to brake the cars. I dont have any pictures up yet. (25 years ago, 6-Jan-00, to lugnet.robotics)

3 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