Re: [mowbot] A Lurker Says, "Hello".

Thomas A Maier (tmaier+ nospam at
Mon, 23 Sep 1996 15:23:10 -0400 (EDT)

> Most of the man-made surfaces are hard and flat and so should give a
> good ultrasound echo.

Good idea, I had considered that one myself. The only problem is that
most 40 KHz ultrasonic transducers have such a long "ringtime" (~1msec)
that they are blind to anything in the first ~.5 ft (.5msec out and
.5msec back). I expect that we're going to be closer to the ground
than that. The Polaroid style might be able to handle the up close
measurements but at higher cost. Perhaps mounting the sensor higher so
that it is looking farther down would unmask the ground return.

**** ATTENTION - Soapbox Erection Zone ******

Also, please, let's not let the the processor warz start here, too. You
can usually hear them coming when you start to hear comments like
"...well, the processor I pulled out of this here obsolete cruise missle
is cheaper, better and ______ (you fill in the blank) than brand X,
model Y that no one except the Joint Chiefs of Staff can purchase..."
etc. (no barbs intentionally aimed at anyone in particular).

Look, EVERYBODY has their pet processor and for their particular
needs/budget/level of expertise/development system/point of view/etc.
that IS the best one. Bar None!

BUT, The purpose of this group is, at least as I understand it, is to
discuss the general design issues peculiar robotic goats--I *still* like
that term better--not to build them for mass production. THAT is where
the processor selection discussion should start. If I am wrong then
please de-subscribe me because I wandered into the wrong group by


****** End of Soapbox Erection Area ****** where the heck did this soapbox come from??? Why, a guy could
get hurt if he climbed up on that thing. :-) :-) :-)