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Shock Sensors

TheRacket

Dec 21, 2015
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Dear All

Very first post and first foray into the world of electronics. My son (13 years old) has had a couple of ideas and we wanted to start learning about electronics with a small project. I know nothing about electronics either.

Firstly, we want to detect a small shock - say from a coin dropping on to a piece of wood - and then have an action based on that shock - A sound is played on a speaker.

Is this the correct forum to be asking these questions? If so, what do you recommend for we buy to build our prototype?

Doing our initial research it looked like the following was a good cheap way of detecting a shock:

http://www.farnell.com/datasheets/43406.pdf

P. 26 - Piezo electric ceramic - But dont know how to order this or equivalent.

I imagine I would have to relay this sound to a micro controller, and then play a selection of sounds on a speaker.

Many thanks for any pointers you can give - trying to support my son in learning about this stuff, and trying to get my grey matter up to speed as well.

Racket.
 

dorke

Jun 20, 2015
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Welcome to our world.
I think that this projcet is not at all for beginners.

First,you may try activating a LED with a light sensor.
Then do that with a transistor.
And then go a bit more "advanced"
 

TheRacket

Dec 21, 2015
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I'm afraid unless he starts working on an element of his idea, hes gonna fizzle out quickly. What about a shock sensor lighting a light?
 

Bluejets

Oct 5, 2014
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Firstly, we want to detect a small shock - say from a coin dropping on to a piece of wood - and then have an action based on that shock - A sound is played on a speaker.

Why overcomplicate the circuit.
If you want the above then just a microphone and small amp with the microphone taped to the wood block ?
 

Anon_LG

Jun 24, 2014
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This project could be very complex if you wish to use a digital output. This requires op-amps with overvoltage protection and massive impedance inputs to prevent the piezo element from frying the control circuitry. I agree with dorke, the project you describe is far too complex for a beginner.

However, if you are dead set on your goal see below.

Attach the output of your piezoelectric element to a neon bulb, neon bulbs take an input of approximately 80 volts to llight in order for any useful current to flow (a non-ohmic component). The impact should light the bulb momentarily.

The above is in itself a working circuit, you might have to experiment with resistors to ensure that the element does not produce a voltage so high as to fry the bulb, to limit the current, but most probably no resistor will be required.

Finally, if you also wish to produce a more complex output (eg sounds), position an LDR next to the neon bulb to form an optocoupler. This optocoupler can feed into an analogue input on a microcontroller, triggering any desired output. This final section is no small task, you would have to be committed to research. You may want to stick with the first section for now, the simple circuit.

The above circuitry described assumes that the coin impact produces a useful voltage (80V <) across the piezo element.

I am 15 myself and my interest in electronics was initiated by this site at the age of 12. It is very important that your son get a working project of some sort. It takes patience however to construct working circuitry and learn the theory that is required to design your own. Is your son interested in reading? If so ensure that he finds a suitable book on the subject, I would recommend Electronics for Dummies. Also ensure that nobody is overambitious in aims. You would not expect a beginner carpenter to craft a life-like sculpture of an ostrich (or something along those lines). Find some more basic circuitry online, a 555 astable circuit is a rewarding build for any skill level. I recommend this particular circuit as a starter project to display the usefulness of electronics.

I hope this helps,
 
Last edited:

dorke

Jun 20, 2015
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I am 15 myself and my interest in electronics was initiated by this site at the age of 12. It is very important that your son get a working project of some sort.
,

Long,Long ago when I was 13, my intrest in Electronics was started in a hobbiest club by...
building a very crud wood hendle 80W soldering iron...I still remember how proud I was of that :).

Good on you,
from your posts, I could have never think you are only 15;)
 
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