View Single Post
  #25   Spotlight this post!  
Unread 12-01-2004, 12:26
Kevin Watson's Avatar
Kevin Watson Kevin Watson is offline
La Caņada High School
FRC #2429
Team Role: Mentor
 
Join Date: Jan 2002
Rookie Year: 2001
Location: La Caņada, California
Posts: 1,335
Kevin Watson has a reputation beyond reputeKevin Watson has a reputation beyond reputeKevin Watson has a reputation beyond reputeKevin Watson has a reputation beyond reputeKevin Watson has a reputation beyond reputeKevin Watson has a reputation beyond reputeKevin Watson has a reputation beyond reputeKevin Watson has a reputation beyond reputeKevin Watson has a reputation beyond reputeKevin Watson has a reputation beyond reputeKevin Watson has a reputation beyond repute
Re: IR Sensors- will they attack hot Chiaphuas?

Quote:
Originally Posted by Al Skierkiewicz
OK, Before you guys get too crazy...
Too late .


Quote:
Originally Posted by Al Skierkiewicz
That is, bursts of 40kHz modulated IR energy. The night illuminators on cameras are just that, steady state, non modulated sources the same as hot bodies.
Yes, as Al correctly (again) points out, the Vishay TSOP4840 sensors that are included in the kit and also used for the kick-off demo specifically discriminate against these type of energy sources. They also discriminate against non-modulated 40KHz sources. I've put a link to the data sheet here: http://kevin.org/frc. The modulation scheme is discussed in this thread.

-Kevin
__________________
Kevin Watson
Engineer at stealth-mode startup
http://kevin.org