Spotting with sound?

[.20calguy]

A nearby powder burner club is inviting me out for a look see.
Their range is out to 800 yards, and he was explaining his accomplisments, and vision to complete it.
He said that members can shoot electronic targets out there. ?? Ok what are electronic targets?
He said "basicly," that there are four microphones at each corner of the target. Each mic hears the bullet penetrate the target at at different times, according to their distance from the POImpact. That info is fed into a computer which recreates the target and the POI, at the shooters bench.

I'm wondering what the speed limitations of that device would be? I know their targets are huge creating a longer sound travel time?

Thats the first I've heard of this one.
That is similar to the technology used in Arak to locate enemy fire positions, for targeting.

 

[delooper]

I'm wondering what the speed limitations of that device would be? I know their targets are huge creating a longer sound travel time?

What do you mean by speed limitations? It looks like the only speed relevant for this kind of target is the speed of sound. The speed of sound varies a tiny bit, but it's not all that relevant for these triangulation computations. The speed of your projectile isn't relevant -- it will tell you where a bowling ball hits, just as easily as a 50 BMG. The microphones each pick up the sound of the impact, and they compare the time recorded at each mic. You really only need 3 mics for this computation, but 4 likely adds quite a bit of stability and redundancy to the system.

 

[woogie_man]

I have a eange in my area that has targets like this. Even at 100 yards the detection is spotty at best with an airgun.

 

[.20calguy]

What do you mean by speed limitations? It looks like the only speed relevant for this kind of target is the speed of sound. The speed of sound varies a tiny bit, but it's not all that relevant for these triangulation computations. The speed of your projectile isn't relevant -- it will tell you where a bowling ball hits, just as easily as a 50 BMG. The microphones each pick up the sound of the impact, and they compare the time recorded at each mic. You really only need 3 mics for this computation, but 4 likely adds quite a bit of stability and redundancy to the system.

Speed limitations? Of the technology with the idea that it could be emlpoyed on smaller targets, for airgun use.
On smaller targets the distance from the sensors to the POI, would require a finer sensitivity for the time measurement.


I never really mentioned projectile speeda.

 

[.20calguy]

I have a eange in my area that has targets like this. Even at 100 yards the detection is spotty at best with an airgun.

That was my question.

 

[Bam86]

This is the technology they use for the indoor 10m air rifle/pistol matches. It is what they use in the ISSF matches for the official scoring. The targets don’t even have scoring rings on them. I didn’t know it was used for powder burners at longer ranges. Neat.

The microphones just need to be able to hear the bullet smack the paper. I assume they need to filter out the background noise on an outdoor range. Probably the light smack of a pellet at 100 yards is being filtered out.

Never actually seen them used in person, but used to watch a lot of the air pistol matches on YouTube.

 

[dv8eod]

There is another system that uses a backstop with accelerometers attached. Targets are attached in front and pellet smacks the backstop, the accelerometers pick up the vibrations then all sorts of mathmagics goes on giving the same results as the microphones. Downside of the microphones is passing through a previous hole. Downside of the other is replacing the backstop.

 

[Long_Gun_Dallas]

I imagine the calibration relating to sound signature or volume would be most relevant. If it's calibrated for much louder projectiles (heavy lead/metal slapping steel) lighter, smaller sound signatures may not be detected as well/easily.

 

[Northwoods22]

Here's an interesting article about electronic target scoring systems (e-targets) and how they work-

An NRA Shooting Sports Journal | Electronic Targets—Coming to a range near you?

With their ability to instantly display the shots of every shooter on a scoreboard, will e-target systems increase participation?

www.ssusa.org

 

[.20calguy]

Here's an interesting article about electronic target scoring systems (e-targets) and how they work-

An NRA Shooting Sports Journal | Electronic Targets—Coming to a range near you?

With their ability to instantly display the shots of every shooter on a scoreboard, will e-target systems increase participation?

www.ssusa.org

Yes I started reading this one, but haven’t finished it yet.
The club who is using this system is NRA affiliated, with several NRA matches coming up.

 

[dv8eod]

The systems that the NRA and CMP use are pretty expensive, so I came up with the idea to use LEDs. Had everything working in that it would tell me I hit the target, just not where. Something about my knowing absolutely nothing about how to program a Basic Stamp (the only thing I have on hand).
It was setup as if the sensors from a chrony were 90⁰ to each other.
If you participate in the CMP matches and don't have the electronic system, they will send you serialized targets that you can scan and send in.