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 / 20365
20364  |  20366
Subject: 
Re: legway :only lego parts
Newsgroups: 
lugnet.robotics
Date: 
Tue, 4 Mar 2003 03:02:53 GMT
Viewed: 
725 times
  
In article <3E63F5B8.2040108@airmail.net>,
Steve Baker <sjbaker1@airmail.net> wrote:

Hmmm - so it looks like the solution to the "Lego sensor isn't
sensitive enough" problem with the Legway has been simply (if a
little un-prettily) solved by sticking it out on a long arm to
magnify the amount it moves when the robot tilts.

There were other contributions to his solution.

1. Reading the babelfish translation (babelfish.altavista.com), I note that he
used a non-Lego part to increase the amount of light reflected to the sensor.
2. He used a freely pivoting weight, I think to primarily to dampen the
corrective action of the motors, helping to prevent over-correction. I
speculate that it allows the angle to be corrected quickly without having to
also deal with a large momentum change.
3. He mounted his RCX and weight high. Someone explain to me how this helps.
It's counter-intuitive to me. Does the increased angular momentum make it less
likely to fall once it's balanced ("an object at rest tends to stay at rest")?
But doesn't this also make it harder to correct once it has started falling
("an object in motion tends to stay in motion")?



From the pictures it looked like the "solution" was to place an
out-rigger on it to keep it from falling over.


From the video it's clear the thing really is balancing. It did need help to
initially "find its feet". Perhaps a SMOP (small matter of programming) would
allow it to get off its outrigger on its own, as Legway II does so dramatically.



Message has 1 Reply:
  Re: legway :only lego parts
 
(...) It's hard to imagine what that could be - a lense maybe? (...) Yes - I guess so. (...) Yes - exactly. It takes more force to start it moving once it's balanced. f = m * a so if the mass is higher, it accellerates more slowly for a given amount (...) (22 years ago, 4-Mar-03, to lugnet.robotics)

Message is in Reply To:
  Re: legway :only lego parts
 
(...) From the pictures it looked like the "solution" was to place an out-rigger on it to keep it from falling over. (22 years ago, 4-Mar-03, to lugnet.robotics)

9 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