South Carolina: "North Charleston to test new gunfire detection system"

[cuchulainn]

http://www.heraldtribune.com/apps/pbcs.dll/article?Date=20030128&Category=APN&ArtNo=301280827&Ref=AR

North Charleston to test new gunfire detection systemBy BRUCE SMITH
Associated Press Writer

A new system that will allow police to pinpoint gunshots is ready to be tested in North Charleston and a similar system will be in operation in Charleston this spring, U.S. Attorney Strom Thurmond Jr. said Tuesday.

The detection system, called ShotSpotter, is manufactured by a company of the same name and uses elevated acoustic sensors in neighborhoods where there often is gunfire.

The six to 10 sensors per square mile are connected by phone lines to a computer in a 911 dispatch center. Using the information from the sensors, the computer can triangulate the location of the gunfire and display the location, accurate to within about 40 feet, on a computer map.

While the sensors pick up the loud crack of gunfire, they also record quieter noise like speech, according to the company's Web site.

Thurmond announced last year the systems would be put in place as part of Project Cease Fire, a local-state-federal government effort to crack down on those who commit crimes with guns.

Under Project Cease Fire, which started in the Lowcountry in 2001 and was expanded statewide last year, state and federal prosecutors cooperate to bring cases in either federal or state courts, wherever the sentence for the gun crime is the toughest.

In South Carolina, firearms are involved in 23 percent of violent crimes, and in 1999, 72 percent of all armed robberies were committed using firearms, Thurmond said at the time.

ShotSpotters are in use in communities in Arizona and California, Thurmond said.

According to the company's Web site, communities that have used the system have reported sharp drops in gunfire incidents. In a square-mile area of south-central Los Angeles, about 1,100 gunshots were reported on New Year's Eve 1991. The next year, there were only four.

 

[TexasVet]

Please, please tell me that these things can't discriminate between gunfire and firecrackers! There is SO much fun going to be had there!

"they also record quieter noise like speech"...

Please don't shoot me, Mr Robber! (snicker, snicker) then the sound of six firecrackers.

I wonder what happens to them when they detect the sound of a cherry bomb TAPED to the detector?

I don't know what the heck is with me tonight. I've got this huge civil disobedience feeling for some reason! Maybe it's because of all the dumb politicians on TV all evening.

 

[Waitone]

And that sir will be a problem in SC since the state has virtually no restrictions on fireworks. This oughta be rich.

 

[Hand_Rifle_Guy]

Got these widgets in my town. Palo Alto's affluent like that.

Dunno about their relative sensitivities, but in my experience, gunshots are several orders of magnitude louder than firecrackers. Additionally, fireworks of the unsafe and insane variety are unavailable in this state.

And the little boxes are mounted on the booms of the streetlights, making them unnaccessable except to the likes of a hydraulic bucket lift.

But faking 'em out is an interesting thought...

 

[Blackhawk]

Big Brother is listening....

 

[m.i.sanders]

I'm not all that suprised about it starting down in the Low Country. Place has been overran with Yankees and Democrats for years. I expect those sensors will get a lot of use from bored teenagers. Seriously, I wonder at the constitutionallity of the whole project. If they start listening for guns shots, what's going to be next, listening to conversations in attempt to catch illegal activities?

 

[DadOfThree]

Dunno about their relative sensitivities, but in my experience, gunshots are several orders of magnitude louder than firecrackers.

They are if the firecracker and gunshot are the same distance away but how would the machine tell the difference between a cherry bomb next to the detector and a gunshot from 3 blocks away? Trying to trick it was what came to my mind before I even finished reading the article

 

[foghornl]

Hmmmmmmmmmm............

the average range of the $2/dozen bottle rocket before explosion is about 150 feet vertical, so launched from a 45 degree angle.....

 

[Chris Rhines]

I have a feeling that some of these things are going to meet the same fate as those video traffic cameras...

- Chris

 

[jrhines]

Most of these types of acoustic sensors detect rise time (how fast does a sound occur), as well as amplitude (how loud was it?). The rise time will give a good indication of what caused the bang (i.e. gun or firework). There are remote detonators that will discriminate between gunshots and HE. To do the whole job there needs to be multiple sensors measuring the difference in time of arrival (TOA) of the particular incident. The standard bug-a-boo for these things is what is called multipath. A bang will echo off buildings and bounce around so you don't really know where it's coming from. But that being said, a loud bang right next to one sensor would indicate such a short TOA compared to other sensors in the matrix that it could be localized to that single sensor pretty quickly.
Now you guys go shooting off fireworks around these things are only gonna' get fireworks banned, too! My suggestion, use that energy to go to the range and practice

 

[dev_null]

Seriously, I wonder at the constitutionallity of the whole project. If they start listening for guns shots, what's going to be next, listening to conversations in attempt to catch illegal activities?

You'd best believe it. All for our own good, of course.

"Winston Smith, you're not doing your exercises!"

-0-

 

[LawDog]

Would it be considered poetic justice of the ShotSpotter records the gunshot that launches a .22LR through the ShotSpotter microphone?

Creatively articulating, of course.

LawDog

 

[PATH]

I beleieve it would be the height of Irony and thus I believe poetic justice would be an apt description. Imagine the locals shooting the sensors!

 

[m.i.sanders]

I CAN imagine that. No one's ever said Southerners were always the sanest people

 

[Waitone]

If traffic signs are any indicator, those sensors will have short, tough life.