October 1962 Popular Electronics
Wax nostalgic about and learn from the history of early electronics. See articles
published October 1954 - April 1985. All copyrights are hereby acknowledged.
Here is an interesting article
that appeared in a 1962 issue of Popular Electronics magazine discussing some of the early electronic
system developments that were based on sensory elements found in nature. I'm a bit
surprised and disappointed that the author made the mistake of equating a bat's
sound-based detection and navigation system to radar rather than sonar. Yes, the
principles of operation are the same regarding transmitting a signal and then computing
the distance based on the round-trip time of the reflected signal, but there is
a fundamental difference between radar which uses radio (the 'ra' part of radar)
signals and sonar which uses the sound (the 'so' part of sonar) signals. I would
bet that if I had the following December or January edition of the magazine, I would
find a letter to the editor pointing out the error.
radar = radio detection
and ranging | sonar =
sound navigation and ranging
Frog's Eye Points the Way Toward New "Selective-See" Radar
Nature is the teacher, man the student, electronics the gainer in this strange
new scientific venture
Scientists who "invented" radar just before World
War II found themselves in for a surprise. Shortly after the first successful units
went into operation, they realized that their invention wasn't new at all. In fact,
it was millions of years old.
Bats, they discovered, had been using their own personal radar systems to steer
in the dark before man was even "out of the trees." Had we known as much about bats
as we do now, radar and sonar might have been developed decades earlier.
Are there other areas in which we can learn from nature? Researchers in the exciting
new field of bionics - the science of building electronic circuits that copy living
creatures - say there are hundreds, maybe thousands of such areas. Bionics scientists
are taking advantage of the fact that through millions of years of trial and error,
nature has developed creatures that can perform tasks of unbelievable precision
One example: a tiny hummingbird navigates 4000 miles so accurately that he ends
up in the same nest he left the season before. A second example: a mosquito can
detect the faint buzzing of another a hundred yards away, in spite of howling winds,
thunder, screaming sirens, and other ear-splitting noises loud enough to drown out
a brass band or a fire brigade!
Fly was source of "new" gyroscope developed by Sperry Rand, yet
insect's "flight instrument" is 50 million years old!
Incredibly complex but extremely effective, a frog's eye responds
only to the two things that interest a frog most: bugs (food) and large objects
Frog's eye center inhibition photocell illuminated.
Frog's eye center photocell in shadow.
Frog's eye center photocell and excitatory photocell in shadow.
Bat has used [son]ar - one of nature's many secrets - for countless
centuries, but man stumbled onto the technique only decades ago.
From Beetles to Flies. By studying these creatures and finding
out how they perform their seemingly impossible jobs so easily and accurately, bionics
scientists are getting clues on how to build better electronic gear. Here's what's
already happened .
Two scientists in Tubingen, Germany, wondered how one kind of beetle, being such
a little fellow, could keep such ac-curate track of his position. They put the bug
in the center of a revolving cylinder so that a moving pattern of lights played
over him. And they found that the way he turned depended on the direction and speed
of the moving lights. The beetle's eyes - multi-faceted like a cut diamond - could
accurately integrate information to judge speed and direction.
American engineers used the same principle to build an artificial two-faceted
eye which can also calculate the speed of moving-light patterns. Put it in a plane,
aim it toward the ground, and it becomes a highly accurate new kind of ground-speed
Why will frogs try to eat anything roughly bug-sized which moves into their range
of vision, yet starve to death when knee-deep in freshly killed insects? Investigators
at M.LT. moved objects of all sizes and shapes in front of frogs, then recorded
their brain waves. Their findings: a frog's eye doesn't see bugs at all. But it
is a cleverly designed sensor that detects two things: moving, bug-sized objects
within range of the frog's tongue, and large objects - an approaching bird, for
example, which might be an attacker. The first signal makes the frog try to eat
whatever comes within range; the second sends him hopping for cover. (One scientist
pointed out that the frog must also be able somehow to spot objects his own size,
or there wouldn't be any more frogs!)
Using the principles learned from the frog, RCA scientists are building an electronic
eye which will be able to spot moving targets and ignore all others. A new kind
of radar that will record only important data, and eliminate everything else from
the screen, could come out of this work.
Using a frog's eye as their model, scientists at Bell Laboratories have devised
an experimental electronic "bug detector" which may well form the basis of much
more important developments. Since the center photocell is connected to the "inhibitory"
input, the neuron will fire only when a small object cuts off the input to this
cell alone. Possible outgrowth of the study: a new kind of "selective-see" radar,
so discriminatory that it will show only the desired data, eliminate all extraneous
material from its screen.
Scientists at the Rockefeller Institute in New York found that the horseshoe
crab was perfectly adapted to seeing in a murky, underwater world. The reason: his
eyes automatically make objects stand out more clearly.
General Electric engineers took the basic principle and designed electronic equipment
to do the same job. They came up with gear that may help make weak TV pictures from
space satellites much sharper and therefore much easier to analyze and interpret.
At Sperry Rand, engineers wondered how a fly managed to flit around so erratically,
yet maintain perfect balance. The answer: flies have two tiny gyroscopes. Unlike
our rotating gyros, though, the flies' stabilizers vibrate like a tuning fork. Sperry
has built a model about the size of a flashlight for keeping missiles on course.
Jam-Proof Bats. Other scientists are
working overtime to uncover scores of natural "secrets" that may give clues toward
building more useful equipment. At Bell Labs, workers are trying to find out exactly
how a bat's super-sensitive hearing works. We already know about his radar, but
they think we may still be able to learn a trick or two from the furry flying mammals.
It's easy to see how a single bat flies into a cave, sends out his personal radar
bleeps, and spots obstructions. But bats seldom fly singly. Hundreds - or even thousands
- swarm into caves at once, all with their radars going full blast. With thousands
of nearly identical echoes bouncing in every direction, how does a bat spot his
To find out, Bell Labs scientists anesthetize bats, insert tiny microelectrodes
into their ear nerves, play recorded bat squeaks, and see what kind of signal the
nerve puts out. If they ever find out how the bat makes himself jam-proof, they
may be able to apply the same principle to radar.
Insect Guidance Systems. Electronics scientists have done wonders
with microminiaturization, but Mother Nature makes their efforts seem clumsy. Take
navigational gear, for instance. A reasonably accurate guidance system which takes
bearings on the moon or stars can be built to fit into an airplane or missile. With
latest miniaturization techniques, it may be only as big as a football and weigh
hardly more than five pounds.
The common sand flea navigates around the beach by taking bearings on the moon,
too. Yet his entire navigation system is smaller and weighs less than the period
at the end of this sentence.
A gentleman silk moth, looking for his girl friend, spots her a mile away by
her aroma. His sensitive smeller detects as little as one or two molecules of scent
floating in the air. By comparison, our noses require thousands of molecules before
we become aware of even the faintest odor. An electronic nose as sensitive as the
moth's would make a dandy gas detector. It could analyze unknown compounds in the
laboratory by sniffing them, identify a handkerchief's owner more quickly and accurately
than a bloodhound, and detect the first hint of food spoilage long before noticeable
or harmful decay could set in.
The praying mantis houses a computer of unbelievable
speed and accuracy in his match-head sized cranium. The insect's eyes see a bug,
and transmit data on the size, speed and trajectory of the flying snack to his brain.
Instantly, the brain goes into action, processes the information like a gun-aiming
computer, and tells him where the bug will be a fraction of a second later. His
head shoots out, and the flying bug becomes lunch. The whole operation takes one-twentieth
of a second. Our tracking systems, weighing tons, aren't that good.
Neuron Nets. All the projects mentioned so far have to do with
receptors: the devices living creatures use to see, hear and feel. But what really
gets bionicists excited is the more far-reaching problem: how do they think, reason
and learn? With answers to questions such as these, we'll be able to build computers
that are not simply souped-up adding machines, but which can reason and learn like
living things .
Key "switch" in living creatures is neuron cell. When impulses
come in on dendrites (D), body of cell (B) "fires." Output pulse leaves on axion
(A), passes along to the next cell via synapse (C).
The secrets are locked in the basic nerve cell, the neuron. These tiny building
blocks of all living brain and nerve systems, scientists now know, are basically
switches. A neuron has many inputs (perhaps several thousand) and one output. Some
of the inputs tend to turn it on - make it "fire" or generate an output pulse. Others
tend to keep it from firing. Whether it fires or not depends on the balance of "ons"
and "offs" at the inputs at any given moment.
Some two to three billion neuron pulses are shooting through your nerve/ brain
system every second. Your eyes alone may generate as many as two billion and send
them streaming along the incredibly complex interconnected nerve pathways to your
brain. Still only dimly understood is what the brain does with all these pulses
- how it tells from a lot of little spikes of electricity what your eyes are seeing.
Big hurdle for electronics scientists "copying" nature is in
perfecting devices which can "think," just as nature's can. Progress in this area
is far from scanty: bionic "mouse" pictured here can learn to run maze just like
real mouse. Apparatus in background is bionic mouse's "brain."
Electronic neuron in schematic above was developed by Bell Laboratories,
works much like natural neuron. When enough signals appear at its five inputs, circuit
generates a single output pulse; device requires bigger signal at excitatory inputs
if signal appears at inhibitory input. Mounted on printed-circuit board (left),
electronic neurons are assembled into experimental networks (one appears in background).
Bionic machine built by Ford Motor's Aeroneutronic Division,
uses artificial neurons, can learn to recognize letters of the alphabet.
But with an increasing understanding of the operation of neuron nets, scientists
are beginning to be able to duplicate some nerve cell functions in an elementary
way. An artificial neuron designed by L. D. Harmon of Bell Labs has five inputs
which can be stimulated to fire the neurons, and one which inhibits firing. Bell
scientists used this artificial neuron to build a simple "bug detector" similar
to the frog's.
Bionic "Mouse." As mentioned earlier, RCA is working on a far
more complicated moving-target indicator containing hundreds of neurons which operates
on the same principle. But perhaps the most important piece of neural-bionic hardware
to come out of the laboratories so far is a "bionic mouse" built by the Mel-par
Corporation. The "mouse" is housed in a small red plastic case about the size of
a matchbox, mounted on wheels. A thin umbilical cord of control wires, suspended
from a freely moving arm above, allows complete freedom of movement and connects
the mouse with its "brain" mounted in a relay rack.
Although the mouse looks like a toy, U. S. Air Force scientists working with
it aren't playing. They are convinced that the mouse is the first step toward a
completely new kind of thinking machine, as different from today's conventional
computers as a superhettfrom a crystal set.from a crystal set.
Not long ago, in a laboratory at the Wright Air Development Center in Dayton,
Ohio, the author saw this "mouse" put through its paces. A technician placed it
in a maze and flipped a switch. The mouse ran down alleys, turned corners, came
to dead ends and backtracked, and tried other routes. Forty-five minutes later,
after exploring scores of wrong turns and dead ends, it reached the end of the maze.
The operator picked it up, and set it back at the beginning.
The second time round the mouse made fewer mistakes, and covered the course in
about half the time. On the third attempt it ran through in eight minutes. Six tries
later, it whizzed through the course in 45 seconds flat without a single error.
The mouse had learned the maze, just as a live mouse would!
Bionic devices display true - though limited-intelligence in the animal sense.
The bionic mouse has only 10 neurons in contrast to our 10 billion, but like an
animal it can adapt to changing conditions and learn from experience. Change the
maze, and it's confused - at first. But then it settles down and learns the new
A bionic "brain," in other words, can operate from generalized instructions.
In the case of the "mouse," the only command was "learn to run the maze." Scientists
call the mouse a self-organizing system which, on the basis of generalized instructions,
figures out how to do the job. Human beings are self-organizing, too. A computer,
on the other hand, has to be "programmed"-instructed in detail on every step. It
must be told when to turn, when to store correct steps in its memory, and so on.
Pattern Recognizers. Bionic brains will eventually take over
hundreds of jobs which are now too complex for computers. They will, for example,
work perfectly as pattern recognizers. Airborne Instruments Laboratory already has
a bionic pattern recognizer which peeks through a microscope and tells cancerous
cells from healthy ones by their size, shape, and general appearance. A Lincoln
Lab version looks over electroencephalograms and spots abnormal brain waves.
Bionic pattern recognizers may someday approach the capabilities of the best
pattern recognizers to date: human beings. Even a baby not yet able to coordinate
well enough to put one block on top of another can instantly differentiate between
his mother and any other human being. Yet the most advanced computer can't approach
this kind of precision.
Future bionic pattern recognizers, though, will distinguish faces or objects
of any kind. Such a device could be put in a missile, shown a map with an "X" at
one point and told to fly over enemy territory until the ground pattern matched
the map, and then zero in.
Handwriting is a pattern, too. An "a" made by one person is very different from
an "a" made by another, yet human beings recognize "a's" easily and read handwriting.
A computer can't do it nearly as accurately as a person can, but there's no reason
a bionic brain won't be able to - and do it much faster than people.
Speech is little more than a pattern of sound waves - also recognizable by a
bionic brain. Dr. Frank Putzrath of RCA is building an electronic ear which will
use a network of artificial neurons to tell one word from another in much the same
way human beings do. With a bionic listener, a business man could dictate letters
to his typewriter. Similarly, a battle commander could direct automatic tanks, missiles,
and guns - just by talking to them.
Educating Bionic Brains. Such brains would share many characteristics
with human brains, among them, the necessity to learn. Today's computers are ready
for operation as soon as the last soldered joint cools. A bionic brain, though,
said Captain Leslie Knapp, one of the Air Force's top bionic scientists, might have
to sit on the shelf for a year or more to become educated. During that time, 24
hours a day, and at electronic speed, it would soak up libraries of information
about scores of different subjects. Then, when given instructions to translate a
paper from one language to another, for example, it would know how.
The usefulness of such bionic machines can hardly be overestimated. A bionic
robot, for instance, could be sent to explore the moon. No computer small enough
to fly in a space ship could possibly be programmed to know how to deal with every
possible condition it might encounter. A relatively small bionic brain, though,
able to adapt to conditions as it found them, would be a perfect agent for the job
of taking man's place on the moon.
Bionic machines may help keep man from being overwhelmed by the fantastic amount
of information he has to receive, analyze, and digest in this age of science. TIROS
weather satellites, for example, have helped weathermen sharpen their weather eyes,
but they've brought problems, too. The flying weather station spews forth thousands
of pictures every day - so many that it becomes almost impossible just to look at
and interpret each one. As more weather stations go into operation, the situation
could become unmanageable.
With a bionic brain aboard, a TIROS satellite could look over each picture to
see if it contained important information. Then only pictures with special patterns
- those showing incipient hurricanes, for example - would be transmitted to the
ground. Similarly, a Midas "spy-in-the-sky" satellite could be directed to be on
the lookout for troop movements and ICBM launchings.
We can expect bionic brains to run factories and offices, control traffic, keep
track of national production, forecast weather, and do thousands of other jobs in
our society. As the industrial revolution produced machines to relieve men of physical
drudgery, the coming bionics revolution should bring forth devices to relieve him
of mental drudgery.
Posted May 3, 2021(original