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Why are you so skeptical of their technology? Look how accurate raspberry pi powered ADSB plane tracking networks are — and that’s a much harder problem: they

Why are you so skeptical of their technology? Look how accurate raspberry pi powered ADSB plane tracking networks are — and that’s a much harder problem: they have no funding, they’re doing triangulation at the speed of light, and they’re doing it without GPS clock sources. You could also point to the lightning tracker networks that work in roughly the same way. Given a few million dollars to outfit their nodes with good GPS units and good microphone arrays, I’d expect their technology to be very good.

danuker 4y ago
In ADS-B, planes broadcast their locations.
- nickysielicki 4y ago
  MLAT time-difference-of-arrival improves the accuracy substantially. Edit: not true, but can provide equivalent accuracy. https://www.flightradar24.com/blog/how-we-track-flights-with-mlat/ https://www.flightradar24.com/blog/how-we-track-flights-with...
  - thethirdone 4y ago
    Your link does not support that assertion. It states that MLAT is used for planes without ADS-B and that it only matches the precision of ADS-B.
    - nickysielicki 4y ago
      Sorry, was going off memory. Thanks for calling me out.
      - danuker 4y ago
        Hats off for graciously accepting cold feedback! Sometimes my HN replies sound more like compiler errors.
sbierwagen 4y ago
I wonder if cell site networks could collect the same data. Cell towers are already mounted high up, have data connections and high precision GPS data. Adding a microphone array seems like it would be cheap and easy.
trs8080 4y ago
"[Office of Inspector General] Finds That ShotSpotter Alerts Rarely Lead to Evidence of a Gun-Related Crime and That Presence of the Technology Changes Police Behavior" - https://igchicago.org/2021/08/24/oig-finds-that-shotspotter-alerts-rarely-lead-to-evidence-of-a-gun-related-crime-and-that-presence-of-the-technology-changes-police-behavior/ https://igchicago.org/2021/08/24/oig-finds-that-shotspotter-... "Police watchdogs in Chicago have issued a report about the city’s use of ShotSpotter’s acoustic gunshot detection system, finding that only 9 percent of ShotSpotter alerts led to evidence of gun crime." - https://www.vice.com/en/article/5db8vk/police-are-using-gunshot-detection-tech-to-justify-stop-and-frisks https://www.vice.com/en/article/5db8vk/police-are-using-guns... "Court documents recently reviewed by VICE have revealed that ShotSpotter, a company that makes and sells audio gunshot detection to cities and police departments, may not be as accurate or reliable as the company claims. In fact, the documents reveal that employees at ShotSpotter may be altering alerts generated by the technology in order to justify arrests and buttress prosecutors’ cases." "And according to the testimony of a ShotSpotter employee and expert witness in court documents reviewed by VICE, claims about the accuracy of the classification come from the marketing department of the company—not from engineers." - https://www.eff.org/deeplinks/2021/07/its-time-police-stop-using-shotspotter https://www.eff.org/deeplinks/2021/07/its-time-police-stop-u...
solardev 4y ago
I'm not skeptical of the technology. Acoustic triangulation has been around a long time. I'm skeptical of this company in particular. See this other comment: https://news.ycombinator.com/item?id=32259253 https://news.ycombinator.com/item?id=32259253 Edit: I think a novel implementation here is that they often use one mic array (several mics mounted around one tower or vehicle) as opposed to a dispersed network at them. If they made that work effectively, I think IMO it's different enough as to be novel and patent worthy. But it also strikes me as the kind of technology that should be defensible on its own merits, and legitimate copycats easy enough to identify, rather than blanket squelching tactics and going after journalists. That's what snake oil salesman do, not companies with actually superior technology. Read the Vice reports. Their effectiveness record isn't great except in their first party sponsored research.
woodruffw 4y ago
Just to point out: on a signals processing level, I suspect that monitoring a signal that's designed to be tracked is much simpler than triangulating a sound using an incomplete acoustic profile. We can track planes via ADS-B with consumer hardware because it's a constrained and well-defined problem that was designed with automation in mind; this is not the case for the noises made by guns in an unknown environment.
daenz 4y ago
Regardless of if it works or not, I suspect some people don't actually want it to work because of the implications: it means there is another viable method for tackling gun crime than "take all the guns." It's easier if it doesn't work, then the only solution is a total gun ban.

danuker 4y ago

In ADS-B, planes broadcast their locations.

nickysielicki 4y ago
MLAT time-difference-of-arrival improves the accuracy substantially. Edit: not true, but can provide equivalent accuracy. https://www.flightradar24.com/blog/how-we-track-flights-with-mlat/ https://www.flightradar24.com/blog/how-we-track-flights-with...
- thethirdone 4y ago
  Your link does not support that assertion. It states that MLAT is used for planes without ADS-B and that it only matches the precision of ADS-B.
  - nickysielicki 4y ago
    Sorry, was going off memory. Thanks for calling me out.
    - danuker 4y ago
      Hats off for graciously accepting cold feedback! Sometimes my HN replies sound more like compiler errors.

sbierwagen 4y ago

I wonder if cell site networks could collect the same data. Cell towers are already mounted high up, have data connections and high precision GPS data. Adding a microphone array seems like it would be cheap and easy.

trs8080 4y ago

"[Office of Inspector General] Finds That ShotSpotter Alerts Rarely Lead to Evidence of a Gun-Related Crime and That Presence of the Technology Changes Police Behavior" - https://igchicago.org/2021/08/24/oig-finds-that-shotspotter-alerts-rarely-lead-to-evidence-of-a-gun-related-crime-and-that-presence-of-the-technology-changes-police-behavior/ https://igchicago.org/2021/08/24/oig-finds-that-shotspotter-... "Police watchdogs in Chicago have issued a report about the city’s use of ShotSpotter’s acoustic gunshot detection system, finding that only 9 percent of ShotSpotter alerts led to evidence of gun crime." - https://www.vice.com/en/article/5db8vk/police-are-using-gunshot-detection-tech-to-justify-stop-and-frisks https://www.vice.com/en/article/5db8vk/police-are-using-guns... "Court documents recently reviewed by VICE have revealed that ShotSpotter, a company that makes and sells audio gunshot detection to cities and police departments, may not be as accurate or reliable as the company claims. In fact, the documents reveal that employees at ShotSpotter may be altering alerts generated by the technology in order to justify arrests and buttress prosecutors’ cases." "And according to the testimony of a ShotSpotter employee and expert witness in court documents reviewed by VICE, claims about the accuracy of the classification come from the marketing department of the company—not from engineers." - https://www.eff.org/deeplinks/2021/07/its-time-police-stop-using-shotspotter https://www.eff.org/deeplinks/2021/07/its-time-police-stop-u...

solardev 4y ago

I'm not skeptical of the technology. Acoustic triangulation has been around a long time. I'm skeptical of this company in particular. See this other comment: https://news.ycombinator.com/item?id=32259253 https://news.ycombinator.com/item?id=32259253 Edit: I think a novel implementation here is that they often use one mic array (several mics mounted around one tower or vehicle) as opposed to a dispersed network at them. If they made that work effectively, I think IMO it's different enough as to be novel and patent worthy. But it also strikes me as the kind of technology that should be defensible on its own merits, and legitimate copycats easy enough to identify, rather than blanket squelching tactics and going after journalists. That's what snake oil salesman do, not companies with actually superior technology. Read the Vice reports. Their effectiveness record isn't great except in their first party sponsored research.

woodruffw 4y ago

Just to point out: on a signals processing level, I suspect that monitoring a signal that's designed to be tracked is much simpler than triangulating a sound using an incomplete acoustic profile. We can track planes via ADS-B with consumer hardware because it's a constrained and well-defined problem that was designed with automation in mind; this is not the case for the noises made by guns in an unknown environment.

daenz 4y ago

Regardless of if it works or not, I suspect some people don't actually want it to work because of the implications: it means there is another viable method for tackling gun crime than "take all the guns." It's easier if it doesn't work, then the only solution is a total gun ban.