Piezo sensor

All discussions here

Piezo sensor

Unread postby Henrique » Sun Feb 23, 2014 5:55 pm

Is it possible to get "close"signal from a piezo sensor?

I would like to use Xnote as a Steel Challenge Timer. I need to capture the close from stop plate hit.
As the plates are fixed ( they do not fall as poppers ) the impact itself should produce some vibration that could be captured by a Piezo sensor attached to backside of the plate.

Can I connect the piezo sensor directly to pins 7 and 8 from a female DB9 connector?
Any clue if this may work or would it be necessary to add some circuitry of some kind?

Thank you
Henrique
 
Posts: 5
Joined: Sun Feb 23, 2014 5:44 pm

Re: Piezo sensor

Unread postby Stopwatch » Mon Feb 24, 2014 3:47 pm

Henrique wrote:Can I connect the piezo sensor directly to pins 7 and 8 from a female DB9 connector?

Yes if your piezo sensor works as a simple on/off switch.
Other option - sound/noise sensor that is supported by Windows 7 (i.e. available under Start->Control Panel->Hardware and Sound->Location and Other Sensors). Unfortunately I know none of them.
Stopwatch
Site Admin
 
Posts: 424
Joined: Thu Feb 19, 2009 6:25 pm

Re: Piezo sensor

Unread postby Henrique » Mon Feb 24, 2014 3:56 pm

Interesting.

On this Windows 7 sensor thing, is this a different connection (physical),or is it just a configuration and de should still work through COM port?
Henrique
 
Posts: 5
Joined: Sun Feb 23, 2014 5:44 pm

Re: Piezo sensor

Unread postby Stopwatch » Wed Feb 26, 2014 7:12 pm

Different connection. Most likely - USB.
Stopwatch
Site Admin
 
Posts: 424
Joined: Thu Feb 19, 2009 6:25 pm

Re: Piezo sensor

Unread postby Henrique » Wed Feb 26, 2014 7:22 pm

I don´t have enough electronics knowledge to play with USB connections.

But for now, I have ordered 25mm piezoelectric discs. I try to use them to close the circuit as an On/Off switch. If this works, I´ll be fine. Otherwise I´ll try to use a mouse circuitry.

I´ll bring my results here.
Henrique
 
Posts: 5
Joined: Sun Feb 23, 2014 5:44 pm

Re: Piezo sensor

Unread postby Henrique » Thu Mar 13, 2014 2:14 pm

Question:

Regarding piezoelectric sensors, If they don´t provide a way to work as on/off switch, I may connect them to an Arduino board so it would read voltage from an analog input( impact in the target plate captured by piezo sensor) and transform it to 0 if there is no input voltage and 1 if there is any volage. This 0/1 from the arduino should be able to communicate with pins 4/6 from DB9 cable. Does it make sense?
Henrique
 
Posts: 5
Joined: Sun Feb 23, 2014 5:44 pm

Re: Piezo sensor

Unread postby Stopwatch » Sat Mar 15, 2014 3:05 pm

Henrique wrote:This 0/1 from the arduino should be able to communicate with pins 4/6 from DB9 cable. Does it make sense?

Try out. You must supply -15..-3 volts as 0 and +3..+15 volts as 1 (see here: http://en.wikipedia.org/wiki/RS-232#Voltage_levels) to 6 pin (DSR) or 8 pin (CTS) with respect to 5 pin (GROUND). Actually 4 pin (DTR) and 7 pin (RTS) already provide always 1 therefore you would need only an on/off switch.
Stopwatch
Site Admin
 
Posts: 424
Joined: Thu Feb 19, 2009 6:25 pm

Re: Piezo sensor

Unread postby Henrique » Mon Apr 07, 2014 4:08 pm

I´ve tested the piezoelectric sensor with direct connection to DB9 female pins 7,8. It has worked flawlessly !
I did a I video but it is in Portuguese and I´m explanining connections and details so it is probably boring for you. but it works.

http://youtu.be/x5TdR1ygQhs

Now I´ll try to put 4 sensors behind the plate in order to avoid blind spots.
Henrique
 
Posts: 5
Joined: Sun Feb 23, 2014 5:44 pm


Return to Main forum

Who is online

Users browsing this forum: Bing [Bot] and 2 guests

cron