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 / 4586
4585  |  4587
Subject: 
Re: Using the IR Port to simultaneously send and receive for proximity sensing
Newsgroups: 
lugnet.robotics
Date: 
Fri, 16 Apr 1999 09:57:46 GMT
Viewed: 
1056 times
  
Peter Hesketh <pbh@phesk.demon.co.uk> wrote:
In article <01BE8785.9B90A2A0.david.cuthill@home.com>, David Cuthill
<david.cuthill@home.com> writes
I haven't really looked into this but can the IR port on the RCX be used to
send out a message and then flip to receive the reflected infrared light
thereby using it as a sensor and still have 3 ports left for other sensors?

Unfortunately the speed of light is *** to fast.

In fact, the IR emitters and IR receiver are in such close proximity that
the receiver already receives whatever the emitters emit, using a direct
path.  The RCX ROM ignores messages it sends out and is thereby able to
avoid getting lost in the confusion.

But yes, the speed of light is too fast and the speed of the RCX MCU is so
slow that if you are trying to do any sort of time-of-flight measurement,
you would be out of luck there, even if you could block the path between
the emitters and the receiver.

-Kekoa



Message is in Reply To:
  Re: Using the IR Port to simultaneously send and receive for proximity sensing
 
In article <01BE8785.9B90A2A0.d...home.com>, David Cuthill <david.cuthill@home.com> writes (...) Unfortunately the speed of light is *** to fast. A reflection from an object 2 feet away would return in 4 nanoseconds. Each data bit of the (...) (25 years ago, 16-Apr-99, to lugnet.robotics)

4 Messages in This Thread:


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

Custom Search

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