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 / 17020
17019  |  17021
Subject: 
Rotation Sensor Information
Newsgroups: 
lugnet.robotics
Date: 
Sun, 13 Jan 2002 20:33:49 GMT
Viewed: 
5837 times
  
I agree this is the heart of the problem...

I made a small experiment and saw strange things on my scope. Has anyone
already open a Lego rotation sensor ? I'd like to have a look to internal
photographs and/or see a circuit diagram.
I tried to open one, but everything seems glued and I fear to break it...

Philo
www.philohome.com

> I don't think so.
> The reason that count is lost is that the A/D conversion
> happens just in the moment when the sensor switches between
> two values, and you get neither of the two but the intermediate value
> on the other side of the cycle:
> 
>     3
>   /   \
> 2      (2)
> |       |
> (1)      1
>   \   /
>     0
> 
> Say you go from 1 to 3 and measure the ghost 2 in between.
> The ROM routine then doesn't change the count,
> and it sets the state to 2.  The end result is a miscount by two.
> My experiments indicated a miscount for on the order of several
> thousand counts.



Message is in Reply To:
  Re: Precise turns of any angle! -- Rotation Sensor Information
 
Hi, I did the rotation sensor fix for leJOS. In the course of that I did a lot of tests and analysed the ROM code, so I know a bit about this. (...) You must have been very lucky. (...) Yes, that's right for the LEGO firmware. For legOS/leJOS it's (...) (25 years ago, 13-Jan-02, to lugnet.robotics)

11 Messages in This Thread:




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

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