SCIENCE
My
professional life was dedicated to the development and use
of acoustical systems to detect and classify biological
organisms in the oceans and in lakes. I did other things as
well, of course, but this was the topic that intrigued me
first in graduate school and was the main topic of my
interest until I retired in 2006. My education was in
Physics and Physical Oceanography but a chance opportunity
to work in underwater acoustics at the Applied Research
Laboratories at the University of Texas, coupled with my
lifelong interest in the sea (California beachbum, Navy,
skin-diver) provided a unique set of tools for me to use.
Then a required class at Oregon State University in
Biological Oceanography, taught by the highly-respected Dr.
Charlie Miller, showed me the wonders of marine life --
particularly the zooplankton -- and connected my
background, skills, and interests into a life-long pursuit.
Along the way, I have gained some experience in areas
related to the devices I created and/or adapted for this
work. Since acoustic systems rely upon transducers to both
produce sound and detect sound, I have used and built a
large number of transducers over frequency ranges from
audible to 10 MHz. Learning from the experts at
ARL,
principally, and reading the literature, I have come up
with some techniques for building and tuning transducers
for both laboratory and field use that may be of some
interest to other researchers.
I learned electronics in the Navy. Of course, the systems I
worked on aboard ship used vacuum tubes! Not very practical
for modern compact sensor systems operating on batteries.
But transistors were not that hard to learn to deal with
and integrated circuits made detailed design knowledge of
transistors less vital to circuit design. Plus, I learned
how to steal circuits and ideas from experts. Folks like
Frank Evans and Walt Dillon at OSU, for example.
Lately, no sensor is considered complete without an
embedded computer. My wife and I took only one class
together at UT and that was assembly-language programming
using a made-up language that was similar to that used on
the CDC-3200 computers of the era. Learning other machine
dialects proved pretty easy. My first high-level computer
language was GOTRAN, an interpreted subset of Fortran that
ran on an obsolete IBM computer that used decimal
arithmetic registers. At UT I took a class in Algol --
based on some wishful thinking by the teacher of the class
who recommended this language lab. I never wrote an Algol
program that accomplished anything but I did learn Fortran
on the CDC machines from a book at ARL. And later learned
Focal and Basic the same way. I learned Forth after
selecting a low-power CPU card for a project in 1990, which
came with this as the operating system. Ended up using
several of their cards (New Micros Inc, in Dallas -- who
seems to be out of business now) in later versions of
sensors and wrote a lot of Forth code. Turns out that Forth
is that dirty little secret buried in lots of consumer
items like digital cameras. It isn't advertised because it
isn't fashionable but it is a way to very rapidly produce
robust code in an embedded system. I cannot stand C or any
of it's derivatives -- it seems to be made up of the worst
parts of all the languages I've ever learned and makes me
crabby to deal with. Bah!
So … my plan is to fill this section of the website with
bits and bobs of stuff I've picked up over the years that I
think might be of interest to folks doing similar work in
biological remote sensing. Or who have a need to build a
laboratory ultrasonics device and don't want to become
experts on all aspects of the design. Also, to illustrate
some disparate applications of ultrasound in the ocean.
The links are organized around several systems that I
designed (TAPS, SandScan, WHAPS) and also by application
(CIRCUITS, TRANSDUCERS, FORTH). When this was written,
these sections were largely blank. I will work as
diligently as retirement allows to fill them up with
content. But ... my racecar beckons.