piclist 2000\12\15\133430a >
Thread: Ultrasonic Sensors
www.piclist.com/techref/io/sensors.htm?key=sensor
flavicon
face BY : Dan Michaels email (remove spam text)



Fred Bailey wrote:
>I have built a few interfaces from PIC's to ultrasonic sensors. Basically, you
>ping (trigger) the transducer using a FET and a good sized inductor (1uH). You
>have to wait for the ping ring to dampen down before you can see the echo
>(Pong).


Hi Fred,

Were you using a Polaroid transducer, or the ceramic kind? I found the
following simple ckt on the robohacking sites. Any comments?

             +5v
              |
             22K  <--- probably too large
              |
              +--------------+
              |              |
              c           U/S xmtr
PIC---1K-----b    NPN         |
              e              |
              |             gnd
             gnd
===========


>The echo amplifier is done with four or more op-amps in series to get about 10K
>gain in total. Many stages are used to keep the frequency bandwidth high.


Uh oh. Guess I would learn this soon as I breadboarded the ckt.
The ckts I've seen had fewer stages with more gain, but you are
certainly right. Hmmm.
========


>Try puting the sensor on a stepping motor and map in all directions.
>

Tom has stepper motors for everything :). My bot will probably
just turn its whole body [initially].

thanks,
- dan michaels

--
http://www.piclist.com hint: The PICList is archived three different
ways.  See http://www.piclist.com/#archives for details.


<1.5.4.16.20001215111413.33ff5476@pop.dnvr.uswest.net>

See also: www.piclist.com/techref/io/sensors.htm?key=sensor
Reply You must be a member of the piclist mailing list (not only a www.piclist.com member) to post to the piclist. This form requires JavaScript and a browser/email client that can handle form mailto: posts.
Subject (change) Ultrasonic Sensors

month overview.

new search...