Interest in personal acoustic target

[JonnyVang]

Ohler has something along those lines. I know it's under there professional series but might be worth checking out to make sure it's in the clear as far as patents. What kind of target area would you build?

Yes you are right. Oehler Research, Inc.--Shooting Bench
The Oehler 86 is a similar system. I tok a quick patent search on Oehler and it seems that they don't use the same algorithms to calculate the hits. But it is a real patent jungle when it comes to acoustic targets. Lots of patents but not many products?

The target are could be several square meters, but the accuracy of the measurement is best right above the microphone array and then it degrades on the sides.

However the Oehler 86 seems like it is targeting very different market than I was thinking of. But I guess it would be smart to seek advice with patent expertise.

 

[JonnyVang]

Here is a pic of my new 12-sensor prototype. Hopefully I will have time to do some test shots over it this week.

 

[royinidaho]

Sheesssh! Everyone is working on the same thing. Great idea. Bryan Litz uses something acoustic.

I've been playing with the same thing.

Way different approach. I tend to way under engineer.

I've put together a system that works in the apartment as a proof of concept.

Using a 5 buck blowgun with darts as a test device. (wife is about to have me committed - need way more space!)

Components include the following LEGOs components:

NXT brick
Sound sensor (microphone)
Piezio sound sensor (fasten to target)

Problems: Down range detection information back to the bench.
Easily fixed with WIFI.

Deal breaker: NXT Mindstorms only counts milliseconds. Not nearly accurate enough for high velocity projectiles.

However, there is a gps on the market that is configured to output microseconds which would, over a period of time, provide for a distance value more reliable than a LRF in addition to the accurate time stamp.

Thus: Time of impact - Time bullet exits muzzle = Time of Flight.

Solution:

Arduino with GPS recording time to the microsecond level. WIFI to xmit back to host Arduino. Increases base cost by 80 bucks.

Another way is use Arduino and piezio sound detector "super glued" to target. WIFI to xmit pluse to stop count at the host.

Start count - Stop Count = microseconds travel time.

Sure wish it were that easy.

If yur into programming (C++ or similar) this is straight forward and quite affordable.

I'd jump on it but I have too many other irons in the fire..............

 

[Wingnut]

Keep working on it!!!!! An affordable acoustic chronograph and group plotter would be the most accurate way to measure accuracy and BC of bullets. I think dopler radar is the most accurate but requires a ton of money and security clearance! You could sell a ton of them if you could keep it under $1000. Keep us all in the loop!

 

[djtjr]

Sounds cool to me. Keep us posted I could be in

 

[JonnyVang]

Teaser from the shooting range:

I have logged 10 shots today, but I have to calculate hits manually to get the result.
The first and only shot I had time to calculate from these 10 was very promising.

2 mm horizontal and 3 mm vertical offset between measured and calculated hit

Hopfully I will have time to look at the 9 other shots later today or tomorrow.

 

[royinidaho]

Good goin'!

It sure looks like you work is paying off.

Never, never, never give up!