HI GUYS I need  your help with our project. our project is entitled energy gathered from doormats using piezoelectric discs. We're having some problem with connecting the discs in series with the regulator, rectifier and battery. we're already running out of time so it would be a big help if anyone would reply with any suggestion or any literature/link/articles/guide... thank you!

sort by: active | newest | oldest
iceng1 year ago

Here is a video of a piezo disc using any DC bridge to charge a 1uFcapacitor.


GretelC1 (author)  iceng1 year ago


iceng iceng1 year ago

This works with any size piezo and any tiny DC bridge you can find.

The circuit is just one section of the piezo generator... Do note a small NIB magnet is holding the disc in place anchored to the metal plate as in the first picture.

BTW I tried series piezo discs and the result was less output, even though I tried to synchronize the mechanical movement.

Keep in mind the piezo is a very high value resistor at no_motion rest..

GretelC1 (author) 1 year ago

guys we really need your help. like right now ty!

iceng GretelC11 year ago


But one piezo can pass a minutiae of current through a diode or several diodes


The circuit below just try a single piezo bridge and a film capacitor, NO Battery yet, see the cap increase with a very high impedance volt meter.

What will happen when there are lots in parallel ?

By the way what are you using to agitate the piezo discs ?

iceng iceng1 year ago

Click the picture to see the entire Image....

GretelC1 (author) 1 year ago

thank guys for the help. unfortunately our work was a failure. we connected our piezo discs in series. and then we connected a 7805 regulator, 0.33 and 0.1 capacitor, in4001 rectifier diode. our plan is to connect an usb extension on its end and see if it could charge a cellphone

Piezos are fairly high impedance output devices. The maximum power you can transfer out happens when ? How can you minimise the output impedance ?

What IS the output impedance of a piezo ? How will you measure it ?

How will you optimise the power transfer ?

What is an energy harvesting device, and where can you find one, quickly ?

What is maximum power point tracking, will it help ?

GretelC1 (author)  steveastrouk1 year ago
the piezo connected in series will be connected in a usb extenion so that we could directly charge a cellphone from the energy fron the piezo

No you won't, no chance in hell.

Get to work on working out the answers to my questions, and you'll begin to see answers.

GretelC1 (author)  steveastrouk1 year ago
at first we got 3 v from 15 piezos connected in series. but yesterday, we only got .3 V MAXIMUM. instead of storing the energy, we connected a usb extension that would directly charge a cellphone with the energy from piezo. i dont know if this would work

How many volts are you getting off the piezo stack ?

What circuit are you using ? What regulator ?

GretelC1 (author)  steveastrouk1 year ago

ok so we tried to connect 15 piezo and we got almost 5 V, But when we tried we cant produce any current. we connected them in series as what our adviser said and we used 7805 regulator. ty!

There isn't a worse part you could use than a 7805. Why ?

Let me guess: another school project gone wrong?

GretelC1 (author)  Downunder35m1 year ago


iceng1 year ago

Piezo discs generate high voltage they can easily each be paralleled with a diode to charge a cap or battery.

" frameborder="0" allowfullscreen>

Sorry about the shaky nature of punching holes in a cardstock with the hole punched holding camera and spark pump freehand.

iceng iceng1 year ago

Here is my concept of a Piezoelectric Generator ...


High voltage bridges too.

I was hoping the12 volt battery would absorb any voltages from going above 25V because the piezo low power output with its high resistance would not overcome a battery comparatively lower resistance, otherwise the generator would be costly...?


BTW were you able to view the video ?

My PC errors me out of any youtube....

Interesting. Any idea just how small you can zap holes like that ?

Glad you could see it... A single shot with the voltage points very close would take a microscope to see a hole but then it may be squirmed around the paper fibers.

Obviously I was going for the biggest hole in a dark cardstock to demo see the miniature lightning holes which occurs as you squeeze the piezo cylinders and again as you release pressure on them. Every time a bolt fires my hand feels a pressure reduction... In a dry winter I can easily spark an inch long arc... Some materials like a glass block or run around an edge..

There's this problem in amateur telescope making, where you need tiny pin-holes to produce a light source. Making tiny holes is an issue. This might work nicely :-)

What material are the pin-holes usually placed into ?

Usually aluminium foil. The standard trick is a needle in a cork.