Oh i can see this being a
right laff on 5th Nov 2011....
The Safer Birmingham Partnership has begun to use communications technology developed in the US to locate the source of gunfire in the city. Birmingham is the first UK city to install the Shotspotter Gunshot Location System. The technology can locate gunshot fire within a 25-metre radius from up to 2km (1.24 miles) away. It …
Now, maybe I'm being thick here, but I assume this is working through some sort of triangulation of the sound? Given that this is a city location, with plenty of buildings etc., surely the sound must rebound around so much as to make this very problematic? Also, doesn't this just make a silencer the object of desire in Birmingham?
A supressor acts by slowing down the projectile so that it does not break the sound barrier. The crack you refer to is the bulllet breaking the sound barrier.
With a subsonic round yoru only really going to hear the propellent going off and the air / gas wooshing out.
So correct in that a supressor does not silence the weapon, but does significantly reduce the acoustic effect of the projectile.
I think that a supressor would defeat this new toy from america.
This is the same Birmingham who installed, and them deactivated, 280+ cameras to keep an eye on Muslim earlier this year. Three million pounds of technology wasted that time:
http://www.theregister.co.uk/2010/06/17/birmingham_cctv/
It's time Birmingham's police weaned themselves off hi visibility, hi risk, hi cost, hi failure, hi tech solutions and tried policing instead.
In response to privacy concerns it was stated that the system only started monitoring sound when it picked up a loud noise.
The more astute reader will not require my asking; Which came first the chicken or the egg?
As always some research is in order rather than trusting in press releases.
in that they could be said to "only monitor speeds when high speed is detected", ie they (generally) only record/transmit speed/numberplate data* when their internal logic is activated by a speed >x.
It would be trivial and the best technical solution to have each of the microphones in the network sit dormant until activated by a sound >XdB, and then they begin processing/recording the sound input and transmitting the appropiate data to HQ.
I imagine the processing involves a little DSP to differentiate 'gunshot' type cracks from all other loud noises, and precise timing of the sound against something like a GPS clock. If you get the precise time that a given sound has reached at least 3 known points, the origin can then be calculated.
*referring to 'traditional' Gatso-type cameras, not ANPR or other hi-tech trickery.
According to the Beeb news website (http://www.bbc.co.uk/news/uk-england-birmingham-11950517), before the 12.07 update and after I enquired about it, the police were apparently quoted to saying that surveillance was not an issue as the sensors recorded decibels and not voices. Needlessly to say I was rather confused and worried by this claim. To add to this rather odd claim, the BBC news website included a clip which clearly showed that the sounds are recorded in full glory, can displayed as waveforms, analysed, and played back.
as yesterday we hear 400 officers are going in Birmingham, due to the spending review. Doubtless this is their PR fightback ...
Well if that means there are fewer plod to harass photographers, and waste their and every body elses time nicking people for a puff of a joint, I won't cry.
Lets see. From newspapers I gather that the majority of inner city shootings are gang/drug related account settling so they are detecting gang on gang shootings which, quite honestly, I couldn't give two hoots about. Now compare the number of these shootings with the number of muggings which occur in Birmingham. Now think which would be more welcome by the general public, extra police patrolling the streets as a visible deterrent to prevent crime or detecting after the fact that some low life has shot on of their peers?
I think the Safer Birmingham Partnership need a very big clue bat.
Blah blah, coppers on beat, blah blah... waffle, outrage, in my day waffle, clip round the ear...
Seriously though, this sounds like a huge waste of time and money that would be far better spent on getting more coppers out of the station instead of stuck behind desks or on the sick. It's really rather scary how thin the cover is for the urban areas I know of (and I know of plenty, just don't ask me how)
The real benefit of installing this (no doubt expensive) system is to the employment prospects of a handful of Birmingham rozzers when they take their early retirement.
"Yes, chief inspector, I'm sure your purchase of this wonderful system will lead to the future expansion of our UK sales team"...........
Back handers are my only explanation for installation of expensive high-tech crap like those huge motorway signs which tell me "beware of spray" when is it pissing down or "14 minutes to J14" when I have no idea where J14 is.
Like all technologies it works but not in the magic/movie sense that this article implies. I can see we're going to have some fun with this system -- it responds to the crack of the gun being fired so I can see a future in tin cans / carbide and propane / air mixtures ("bird scarers") . Certainly if I were planning a hit I'd want to swamp the system, "just in case".
You've got some ace salesmen in the UK. They can sell government *anything*!
We have this system in some of the more crime-ridden areas of the city nearest to me. It DOES cost a lot, break down a lot and yes, it does find gunfire. What it does NOT do is operate effectively - CERTAINLY not effectively for the cost.
Baton Rouge, LA USA. initial cost $3.5million, annual maintenance costs over $450,000 to cover an area roughly EIGHT square miles. Birmingham should save the money and, perhaps, spend it on more [leather shoes*] on the ground.
http://www.2theadvocate.com/news/101233734.html?index=1&c=y
<excerpt>In an April 2008 e-mail, Nick Pizzalato, network administrator for the city-parish’s Information Services department, sent an e-mail to a representative of ShotSpotter.
“How can I convince the police that this is going to help them?” Pizzalato wrote. “They don’t want the system and they don’t think it’s going to be any benefit. I guess when I say they I mean the dispatchers because the field officers don’t even know about it yet.” </excerpt>
* unless, of course, the Birmingham constabulary actually DOES wear boots. Then, the old adage stands as is.
How long before they decide to feed in a voice print and try to match "known criminals".... and then monitor "potential terrorists"... and then say "these are required for the detection of serious and organised crime"... and then, "we heard you say you wanted to blow up the airport if they didn't stay open during the snow-storm!"