"lifeguard(?)": bullet tracking system???

Hey guys, I heard a blurb on the radio a few days abo about something called
"lifeguard" which can track the source of gunfire.  My guess is that they
use acoustics for this.  I don't know how they can claim that it wouldn't be
confused by non-gun noises, nor what silencers would do to this thing.

They also mentioned that some models can be fitted with guns so as to auto
matically return fire...

Is this bullshit?  Anyone else hear about this?  I wish they'd given out
more info on this thing... I heard this on WCBS (AM) in NYC...

This can have some serious big brother is watching effects in bad neighborhoods.
Such a beast could be fitted with a machine gun to simply fire wherever it
hears a bullet come from, potentially killing anyone else who happens to be
near the source of the fired gun, more likely a hostage with a gun to his head
than the holder of the gun... :-(

Ugh, if this is what the crime bill means, I'm all for legalizing drugs just
to get the cops and criminals out of business...  Shit if every pharamacy
sold cheap drugs, or every liqour store, there'd be a gigantic drop ib
drug related murders.  Sure, the ammounts of stick ups and burglaries that
liquor stores would suffer would rise, but, if the FBI, CIA, ??? are already
involved in drug runnimg, they may as well make it legal and stop hiding their
activities.  (Of course if they did their economic strangleholds would drop)

Arsen Ray Arachelian writes:
 > Sure, the ammounts of stick ups and burglaries that liquor stores
 > would suffer would rise

How do you know?  In fact, why would you even suspect this to be the
case?  (Note that a significant motivator for such crimes---the need
for money to buy drugs---would diminish in importance considerably.)

--
| GOOD TIME FOR MOVIE - GOING ||| Mike McNally <m5@tivoli.com>       |
| TAKE TWA TO CAIRO.          ||| Tivoli Systems, Austin, TX:        |
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Oops.  I didn't mean to blast that note out to the list.  Sorry.

--
| GOOD TIME FOR MOVIE - GOING ||| Mike McNally <m5@tivoli.com>       |
| TAKE TWA TO CAIRO.          ||| Tivoli Systems, Austin, TX:        |
|     (actual fortune cookie) ||| "Like A Little Bit of Semi-Heaven" |

C'punks,

On Sun, 29 May 1994, Arsen Ray Arachelian wrote:

> Hey guys, I heard a blurb on the radio a few days abo about something called
> "lifeguard" which can track the source of gunfire.  My guess is that they
> use acoustics for this.

It does.  I saw something about in Popular Science, I think.  It 
strategically placed microphones to triangulate the origin of the shots.

> I don't know how they can claim that it wouldn't be
> confused by non-gun noises, nor what silencers would do to this thing.

There aren't many sounds that are really that similar to gun shots.  For 
one thing most rounds are supersonic unlike firecrackers and car backfires.
There really is no such thing as a "silencer" outside of the movies.  
*Sound supressors* work marginally well for subsonic rounds.  They are 
pretty much useless for supersonic rounds.
 
> They also mentioned that some models can be fitted with guns so as to auto
> matically return fire...

Please.  This is the purest nonsense.  The microphone system only works 
well enough to get the cops to the general vacinity of the shooting.  
However the real issue is legal presumptions and liability.  Ain't gonna 
happen here pardner.


 S a n d y

[With apologies -- no, it's not cryptography.]

Considering the wide variety of gun noises and urban noise
artifacts, a lot of false alarms would be expected.  On the other
hand some of them might be worth responding to from the police
perspective.  It might be preferable to respond to firecrackers
early in the evening and discourage accidental or deliberate
arson later.

On Sun, 29 May 1994, Sandy Sandfort wrote:

> 
> There aren't many sounds that are really that similar to gun shots.  For 
> one thing most rounds are supersonic unlike firecrackers and car backfires.
> There really is no such thing as a "silencer" outside of the movies.  
> *Sound supressors* work marginally well for subsonic rounds.  They are 
> pretty much useless for supersonic rounds.
>  
The above is is a bit of an oversimplification.  Most of what these
gadgets would be listening for are .22/.32/.38/9mm/.45 etcetera.
9mm and 22LR could easily be supersonic, but the other common
ones tend to be slower.  .45ACP, for example, is usually in the
900fps range (or slower), and won't give any sonic signature other
than the shot itself.

Regarding automatic shoot-back> 
> Please.  This is the purest nonsense.  The microphone system only works 
> well enough to get the cops to the general vacinity of the shooting.  
> However the real issue is legal presumptions and liability.  Ain't gonna 
> happen here pardner.
> 
> 
>  S a n d y
> 
As several people pointed out, arming a mechanical device would be
litigationally unacceptable.  Worry about it when private
security firms are allowed to employ mine fields.  Furthermore,
how long would an audio monitor last in the company of a
stealable weapon?  15 minutes?  A more reasonable concern would be
future "upgrades" of the system for greater sensitivity and a wider
range of uses.

  Regards,
    JMJ

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> [With apologies -- no, it's not cryptography.]

> Considering the wide variety of gun noises and urban noise
> artifacts, a lot of false alarms would be expected.  On the other
> hand some of them might be worth responding to from the police
> perspective.  It might be preferable to respond to firecrackers
> early in the evening and discourage accidental or deliberate
> arson later.

The original report on CNN said that LLNL claimed their system didn't use
sound for tracking. They wouldn't discuss further details, since the system
hasn't been patented yet.

Sci.military readers might remember that a debate about these types of
acoustic locating systems took place there a couple of months ago.
Apparently the UK has a vehicle-mounted system that they use to sniff
out snipers in Northern Ireland.

- -Paul

- -- 
Paul Robichaux, KD4JZG      | Out the 10Base-T port, through the router, 
perobich@ingr.com           | over the leased line, off the bridge, past
Intergraph Federal Systems  | the firewall... nothing but net.
	       Of course I don't speak for Intergraph.

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