Ready, Aim, ID Check: In Wrong Hands, Gun Won't Fire

R.A. Hettinga rah at
Thu Jan 6 08:47:57 PST 2005

Ah... Book-entry to the trigger.

The ganglia, as the man said, twitch.

Whole new meaning to digital "rights" management.



The New York Times

January 6, 2005

Ready, Aim, ID Check: In Wrong Hands, Gun Won't Fire

HE computer circuits that control hand-held music players, cellphones and
organizers may soon be in a new location: inside electronically controlled

Researchers at the New Jersey Institute of Technology in Newark are
building a handgun designed to fire only when its circuitry and software
recognize the grip of an authorized shooter.

 Sensors in the handle measure the pressure the hand exerts as it squeezes
the trigger. Then algorithms check the shooter's grip with stored,
authorized patterns to give the go-ahead.

"We can build a brain inside the gun," said Timothy N. Chang, a professor
of electrical engineering at the New Jersey Institute of Technology who
devised the hardware for the grip-recognition system. "The technology is
becoming so cheap that we can have not just a computer in every home, but a
computer in every gun."

The main function of the system is to distinguish a legitimate shooter
from, for example, a child who comes upon a handgun in a drawer.
Electronics within the gun could one day include Global Positioning System
receivers, accelerometers and other devices that could record the time and
direction of gunfire and help reconstruct events in a crime investigation.

For a decade, researchers at many labs have been working on so-called smart
or personalized handguns designed to prevent accidents. These use
fingerprint scanners to recognize authorized shooters, or require the
shooter to wear a small token on the hand that wirelessly transmits an
unlocking code to the weapon.

At the New Jersey Institute of Technology, Michael L. Recce, an associate
professor in the department of information systems, decided instead to
concentrate on the shooter's characteristic grip. Dr. Recce created the
software that does the pattern recognition for the gun.

 Typically, it takes one-tenth of a second to pull a trigger, Dr. Recce
said. While that is a short period, it is long enough for a computer to
match the patterns and process the authorization.

 To bring Dr. Recce's recognition software to life, Dr. Chang created
several generations of circuits using off-the-shelf electronic components.
He equipped the grips of real and fake handguns with sensors that could
generate a charge proportional to the pressure put on them.

 The pressure on the grip and trigger are read during the beginning of the
trigger pull. The signals are sent to an analog-to-digital converter so
that they can be handled by the digital signal processor. Patterns of
different users can be stored, and the gun programmed to allow one or more

 At first the group worked mainly with a simulated shooting range designed
for police training. "You can't have guns in a university lab," Dr. Recce

The computer analysis of hand-pressure patterns showed that one person's
grip could be distinguished from another's. "A person grasps a tennis
racket or a pen or golf club in an individual, consistent way," he said.
"That's what we're counting on."

During the past year, the team has moved from simulators to tests with live
ammunition and real semiautomatic handguns fitted with pressure sensors in
the grip. For five months, five officers from the institute's campus police
force have been trying out the weaponry at a Bayonne firing range. "We've
been going once a month since June," said Mark J. Cyr, a sergeant in the
campus police. "I use a regular 9-millimeter Beretta weapon that fires like
any other weapon; it doesn't feel any different."

For now, a computer cord tethers the gun to a laptop that houses the
circuitry and pattern-recognition software. In the next three months,
though, Dr. Chang said, the circuits would move from the laptop into the
magazine of the gun. "All the digital signal processing will be built right
in," he said.

Michael Tocci, a captain in the Bayonne Police Department, recently saw a
demonstration of the technology. One shooter was authorized, Captain Tocci
said. When this person pulled the trigger, a green light flashed. "But when
other officers picked up the gun to fire, the computer flashed red to
register that they weren't authorized," he said.

 The system had a 90 percent recognition rate, said Donald H. Sebastian,
senior vice president for research and development at the institute.
"That's better fidelity than we expected with 16 sensors in the grip," Dr.
Sebastian said. "But we'll be adding more sensors, and that rate will

Dr. Chang said the grip for the wireless system would have 32 pressure
sensors. "Now, in the worst case, the system fails in one out of 10 cases,"
he said. "But we've already seen that with the new sensor array, the
recognition is much higher."

Dr. Sebastian said the team was considering adding palm recognition as a

To develop a future weapon, the university is working with a ballistics
research and development company,  Metal Storm, of Arlington, Va. "We'll
use our recognition system on their weapons platform," Dr. Sebastian said.

 The Metal Storm gun has plenty of room for the pattern-recognition
circuitry. Rounds are kept in the gun's barrel, not in a magazine in the
grip. There is a small amount of the gun's own electronic circuitry in the
handle to control the firing, said Arthur Schatz, senior vice president for
operations at the company. "Otherwise it's pretty much empty, allowing the
grip system to be housed within the handle," he said.

Captain Tocci of the Bayonne Police Department said the pattern-recognition
technology was promising, particularly because accidental deaths occur when
guns are not safely stored. "If a child picks up a gun that is not secured,
this way it can't be fired," he said. Guns taken from a home during a
robbery would be rendered useless, too.

"The premise the gun is based on has credibility," he said. When people see
a live demonstration of the pattern-recognition system working, he said,
"you think, yes, this is possible."

E-mail: Eisenberg at

R. A. Hettinga <mailto: rah at>
The Internet Bearer Underwriting Corporation <>
44 Farquhar Street, Boston, MA 02131 USA
"... however it may deserve respect for its usefulness and antiquity,
[predicting the end of the world] has not been found agreeable to
experience." -- Edward Gibbon, 'Decline and Fall of the Roman Empire'

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