Need A Little Electronics Help To Measure Barrel Vibration

[CharlieNC]

I acquired a new high speed ADXL1002 evaluation board accelerometer from Analog Devices. It looks like it should be straightforward to wire up, but I cannot get it to work. It is a high speed device with analog output, but I only get a constant voltage output and probably am not interpreting the schematic properly. Unfortunately AD has not been any help.

I know there are some electrical / electronic gurus here; please send me a PM if you can look at the schematic and advise how I should connect this.

Thanks.... Charlie

 

[MGMIAM]

Hi charlie,may I ask what your trying to get results for. I did vibration analysis years ago, and have looked up many articles etc on using accelerometers to do barrel testing, that is if this is what you might be using it for, if not I apologize. I believe to get the results one would need would take very expensive equipment analyzers to read data etc. and you would need a 3 way, x, y,z planes to get data you need. i could be wrong but just trying to help
https://www.jvejournals.com/article/20370
https://www.scielo.br/scielo.php?pid=S1679-78252018000900500&script=sci_arttext
just examples.
Its really hi tech

 

[MGMIAM]

look up modal analysis, this is very interesting, would give you resonant frequencies of item you are using it with.
https://aip.scitation.org/doi/pdf/10.1063/1.4979749
http://citeseerx.ist.psu.edu/viewdoc/download?doi=10.1.1.868.1800&rep=rep1&type=pdf

 

[CharlieNC]

Hi charlie,may I ask what your trying to get results for. I did vibration analysis years ago, and have looked up many articles etc on using accelerometers to do barrel testing, that is if this is what you might be using it for, if not I apologize. I believe to get the results one would need would take very expensive equipment analyzers to read data etc. and you would need a 3 way, x, y,z planes to get data you need. i could be wrong but just trying to help
https://www.jvejournals.com/article/20370
https://www.scielo.br/scielo.php?pid=S1679-78252018000900500&script=sci_arttext
just examples.
Its really hi tech

Thank you, those are excellent resources. I want to use the accel to look at the vertical movement while shooting a ladder test as the point of impact maps out a sine wave, just to see how well the point of impact and barrel movement agree. The parts are so cheap these days I couldn't resist, but the wiring has me stumped (not difficult to do).

 

[CharlieNC]

look up modal analysis, this is very interesting, would give you resonant frequencies of item you are using it with.
https://aip.scitation.org/doi/pdf/10.1063/1.4979749
http://citeseerx.ist.psu.edu/viewdoc/download?doi=10.1.1.868.1800&rep=rep1&type=pdf

Its been 45 years since I studied the calculus; I remember the principles but can not go beyond the basics these days. Thank goodness for computers to bail me out.

 

[MGMIAM]

this is another good article.
http://www.geoffrey-kolbe.com/articles/rimfire_accuracy/tuning_a_barrel.htm

 

[BoydAllen]

Years ago, on a practice day before a match, one of the competitors, who was an actual scientist, was shooting his benchrest rifle with an accelerometer taped to the muzzle, wired to a recording oscilloscope. The rifle was built around a panda action, which of course makes moving rings easy, and so I asked him if the position of the rings and the scope affected barrel vibration. He said that they did. That was at least 20 years ago, at the Visalia range. The fellow's name was Don Jackson, and at the time he lived in Redondo Beach, and posted on Benchrest Central as Don from Redondo.

 

[MGMIAM]

Boyd, could you tune for vertical dispersion with different powder loads ?

 

[MGMIAM]

Charlie, i queried vertical dispersion and powder loads and guess what. a post from you

http://forum.accurateshooter.com/threads/vertical-with-powder-horizontal-with-seating-depth.3955530/

 

[CharlieNC]

Charlie, i queried vertical dispersion and powder loads and guess what. a post from you

http://forum.accurateshooter.com/threads/vertical-with-powder-horizontal-with-seating-depth.3955530/

Yes there is a ton of info about tuners and load development based on barrel harmonics. The literature probably exists as Boyd mentioned the results by Don Jackson, but I have not been able to find it except Kolbe for a rimfire. I like to piddle around and this is an area of interest for me.

 

[Pawnee Bill]

Years ago, we used Sapphire rod vibration transducers to check vibration on J-79 jet engines. Maybe something like that would work.

 

[CharlieNC]

Years ago, we used Sapphire rod vibration transducers to check vibration on J-79 jet engines. Maybe something like that would work.

More than one way to skin a cat. I'm just not smart enough to figure out how to operate this thing.

 

[SGK]

Vout is flat on your oscilloscope?

 

[itchyTF]

What output voltage are you getting? I assume you’re supplying it with 3.3 - 5 vdc?

 

[itchyTF]

Do you have Standby or Selftest connected to anything?

How are you determining it doesn’t work? How are you stimulating it and what are you expecting for an output?

 

[TheOtherZilla]

Hi charlie,may I ask what your trying to get results for. I did vibration analysis years ago, and have looked up many articles etc on using accelerometers to do barrel testing, that is if this is what you might be using it for, if not I apologize. I believe to get the results one would need would take very expensive equipment analyzers to read data etc. and you would need a 3 way, x, y,z planes to get data you need. i could be wrong but just trying to help
https://www.jvejournals.com/article/20370
https://www.scielo.br/scielo.php?pid=S1679-78252018000900500&script=sci_arttext
just examples.
Its really hi tech

I too was into Vibration analysis and monitoring.. You need some high dollar equipment and software to get results.. The accepted methods are used on rotating equipment as far as I know. Personally I don't see it happnin.

 

[itchyTF]

The datasheet states that the zero g bias is half the supply voltage. Is that what you are seeing?

 

[Aceball]

A study of the Ladder Test pattern should reveal the muzzle moment position at the release point. You'll need to connect your board to a good DC power supply, and a Oscilloscope or appropriate Analyzer. If you can get thru to an engineering department with one of the analyzer equipment companies might find a sympathetic ear? I'm a retired Process Control Systems Engineer but this has already strained my three remaining brain cells. (one to eat, one to sleep, one to poop. Sometimes I shoot the poop.) Good luck, wish I could get more involved.

 

[243Mendoza]

Is there a way to change the max and min amplitude of the display? There may also be way to modify the frequencies/wavelengths that can be displayed (filters)?

 

[AllThingsAI]

I’m an Electrical Engineer and have been in the semiconductor industry for a long time. I’ve thought about this measurement a lot. You probably don’t want to attach anything to the barrel itself as this will affect the harmonics. You should look at a device like TI’s LDC or LMP Inductive sensors. The coil doesn’t actually need to touch the barrel and they are highly sensitive to tiny deviations of a metal object.