Gunshot detection

[MasterVision_Tech 0]

Hey Guys,

Im looking for a external interface that has the capability to send out a pulse or voltage(trigger) when a decibel of 140 or higher is reached. Gunshot detection is the name of the game here. The industry leader is a company called ShotSpotter but their prices are out of range for the average consumer. Ive been looking for different alternatives like a sound meter that would measure up to 140db but have been unable to find a device that would.

 

Does anyone have any ideas? Maybe an existing device that I could tweak and run it into the alarm inputs of a DVR?

 

Thanks,

Josh

[Soundy 1]

Would be interesting to take a look at their technology and see what kind of system they're using.

 

I can think of a couple possibilities...

 

When I worked in car electronics, some alarms used a glass-break sensor that was essentially just a microphone in a housing tuned to a certain frequency band - a noise of sufficient level within that band (corresponding to the frequency generated by breaking glass) would generate an output sufficient to trigger the alarm input. You could use a similar concept, feeding the mic into an op-amp comparator, and adjusting the input trigger level as needed.

 

Something else that MIGHT work would be a piezo pickup - a buddy once made a set of "cymbal" pads for an electronic drum kit using these: he cut out a plywood disk, glued a Frisbee or plastic container lid to the top, and attached a piezo pickup to the bottom. Hitting the "cymbal" would cause the piezo to generate an output voltage that triggered the input on the drum brain... in you case, it could be used to trigger an op-amp comparator as well. You'd just need to attach it to some sort of diaphragm that would respond appropriately to the gunshot sound... alas, I have no idea what that would be.

[Malloot 0]

 

This product might be suitable for your case.

[rory 0]

I guess that will work in a perfect world, or a controlled environment.

[bpzle 0]

A device to alarm at 140dB or higher is only going to work if the shots are in extreamly close range... I think the key would listening for certain freqencies past say 95dB...

[rory 0]

also how does it tell the difference between firecrackers, backfiring from vehicles, extremely loud exhausts from both cars and even worse from motorbikes (down here they all have exhausts to make your head explode), and base from the music in cars the kind of base that makes your windows rattle in your home as they pass a hundred feet away. Not to mention most gun shots go off in areas one would never put such an expensive camera, though i guess this is specifically for certain location like a mall parking lot. I like the bit about the response team though, we normally see the cops an hour or so after an incident, if we are lucky, ambulances take about 1-2 hours to turn up also. I guess it would work well in the perfect little neighborhood, the kind that doesnt get much gun shots to begin with.

[Malloot 0]

also how does it tell the difference between firecrackers, backfiring from vehicles, extremely loud exhausts from both cars and even worse from motorbikes (down here they all have exhausts to make your head explode), and base from the music in cars the kind of base that makes your windows rattle in your home as they pass a hundred feet away. Not to mention most gun shots go off in areas one would never put such an expensive camera, though i guess this is specifically for certain location like a mall parking lot. I like the bit about the response team though, we normally see the cops an hour or so after an incident, if we are lucky, ambulances take about 1-2 hours to turn up also. I guess it would work well in the perfect little neighborhood, the kind that doesnt get much gun shots to begin with.

 

It depends on how you want to use the system. I think you should use it as an support for a video surveillance service. So they can check visual if the alarm was caused by a gunshot or due to firecrackers, etc.

 

I think it might be helpful system in certain high risk situation where for example a drive-by shooting can occur.

 

I will never trust a videosystem without a visual check by a human.

 

I think such a system could be a nice addition for certain situations.

[thewireguys 3]

[tomcctv 190]

Hey Guys,

Im looking for a external interface that has the capability to send out a pulse or voltage(trigger) when a decibel of 140 or higher is reached. Gunshot detection is the name of the game here. The industry leader is a company called ShotSpotter but their prices are out of range for the average consumer. Ive been looking for different alternatives like a sound meter that would measure up to 140db but have been unable to find a device that would.

 

Does anyone have any ideas? Maybe an existing device that I could tweak and run it into the alarm inputs of a DVR?

 

Thanks,

Josh

 

 

i was not to shure about this post and how anything like this could work without false alarms. like comments made ... fire works / car backfire. but i read the papers here in the uk to find they have just installed a massive system in birmingham. all done by an american company http://www.shotspotter.com/

 

uk papers

 

State of the art gunshot sensors have been installed for the first time in a British city in a new approach to tackling gun crime.

 

Project Safe and Sound" in Birmingham uses technology which records an audio clip of any gunshot fire and sends police its GPS location, helping them decide how to respond.

 

It can tell if multiple shots were fired, whether they were fired from a stationary or moving location, the number of weapons used, and the order in which they were fired, according to the manufacturers.

 

West Midlands Police said the sensors had been placed high up on buildings in northwestern areas of the city.

 

"This technology will enable us to respond faster and more effectively to firearms incidents, therefore minimising the harm to local communities and maximising the opportunity to seize illegal firearms, catch offenders and potentially save lives," said West Midlands Police Chief Chris McKeogh.

 

The Shotspotter Gunshot Location System is already used in U.S. cities.

 

U.S.-based firm Shotstopper Inc designed the technology, which can pick up gunshot fire within a 25 metre radius from a distance of two kilometres.

 

Police responded to some Birmingham residents' concern that the sensors would be used for surveillance, saying they record decibels, not voices.

[rory 0]

The Shotspotter Gunshot Location System is already used in U.S. cities.

Thats great but is it working?

[tomcctv 190]

The Shotspotter Gunshot Location System is already used in U.S. cities.

Thats great but is it working?

 

 

dont know i havent got a gun . to try it.

[techuser 0]

look at http://www.aurislink.com they provides an interesting alternative. probably cheaper...

Edited February 26, 2012 by Guest

[excableguy 0]

This is the mack daddy of gunshot detection..

 

http://www.dailymail.co.uk/sciencetech/article-2022615/Sniper-snooper-Boomerang-tell-Taliban-marksmen-listening-enemy-gunfire.html

 

 

However.. for CCTV purposes: