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From software algorithms to material selection, Mr. Roboto strives to meet you
where you are — and what more would you expect from a complex service droid?
by
Dennis Clark
The summer flew by, fall is flying by as well, and
competitions loom like the sword of Damocles over our
heads. Anyway, I have a couple of interesting questions,
some commentary, and a discovery to share this month!
Without further adieu, I shall move into the meat of my
column ...
Q. I would like some clarification and help, but I’ll be as brief as possible. I have seen a few different Polaroid sonar projects and yours is one of them.
The original Polaroid project that I saw was from Ciarcia’s
Circuit Cellar by Steve Ciarcia. I may be using a different
board all together, but how can you tell other than looking
at the pictures and compare? The ones I have looked at
are very much like what you and Steve are showing in
your articles.
I have the parts for the Polaroid 660 and the SUN
660 and One Step, which I would really like to get
working. However, I see discrepancies between each
one of these hacks and projects, and I have not been
Figure 1. 660 One Step sonar.
14 SERVO 11.2011
able to make any progress.
In your hack from “Polaroid Sonar hack.html” on
www.seattlerobotics.org/encoder/index.php, I am not
clear as to where you have the “-“ and the “+” terminals
of the “100 µf” capacitor attached to; the picture is very
hard to see.
In that picture, you are showing the pin-outs on the
Polaroid 660 board in Table 1. I am also showing what
Steve Ciarcia has in his Build the SonarTape article
( www.micromint.com/app_notes/ti01_data.htm) for the
“J1” connector in Table 2.
23 4
Vss BLINK BINH (PWR) INIT FIL
1
5
6
7
OSC Echo
8
Transmitter
Base
Table 1.
1
V+
234
ECHO OSC
5
INIT
Table 2.
6
BLNH
78
BLNK GND
So, as you can see I am left puzzled with yet another
mystery.
— Givi (via internet)
A. Let me answer your questions as best I can, in the order you gave them. I think that we can clear this right up. The SRS Encoder article you refer to
originated from my website where I posted the results of
weeks (maybe months) of experiments I did with at least
four different types of old Polaroid cameras that had
sonar boards in them. In those days, there weren’t a lot
of inexpensive options for sensors in general, and
sonar in particular (has it really been that long?). I
scoured the Web, called and talked to Polaroid folks,
and hunted down technical documents to get this
information, but still it was incomplete and I had to
experiment a bit when things didn’t work. My notes were
