Re: Low cost weight sensor ?

Roberto Waltman wrote:
Anton Erasmus wrote:
... Have anyone used piezo electric material to
measure weight ?

Yes, there are piezoelectric load cells. They may be difficult to use
because they require very high impedance analog circuitry to read the
output. ("Charge Amplifiers") See:

http://www.kistler.com/do.productfinder.us.en-us?content=833_ProductFinder_Force&param=3XXX.9021A

Would a piezo speaker be suitable ?

May be... How stable will that be?

Anton, I just read again your original post: "I am trying to provide a
indication of the amount of paper available. The empty container is
approx. 1kg, and approx. 10kg full of paper."

(Stepping out from the box and trying to think.) You choose weight as
the parameter to be measured. What other options are there?
It would be very easy to measure the height of the stack of paper.
(Measure the angle of a hinged rod lying on top of the stack,
ultrasound sensors, etc.)
Light transmitted through the stack will probably not work with 10kg
of paper.
Anybody has any suggestion other than weight?
.

Relevant Pages

  • Re: Add/Subtract or Leave Weight the Same
    ... Standard pulley with a weight stack. ... concentric and compared that to distance of the point A and B ... Then a 25 kg plate. ...
    (misc.fitness.weights)
  • Re: Add/Subtract or Leave Weight the Same
    ... Standard pulley with a weight stack. ... Have you measured the distance of, for instance, the feet during the ... plate. ...
    (misc.fitness.weights)
  • Re: Add/Subtract or Leave Weight the Same
    ... plates actually are in *real* weight equivalence, ... Just the distance they move during the concentric or eccentric. ... Just the distance the stack travels. ... It doesnt matter how many plates you use. ...
    (misc.fitness.weights)
  • Re: Add/Subtract or Leave Weight the Same
    ... plates actually are in *real* weight equivalence, ... Just the distance they move during the concentric or eccentric. ... Just the distance the stack travels. ... It doesnt matter how many plates you use. ...
    (misc.fitness.weights)
  • Re: Low cost weight sensor ?
    ... weight cab be calculated. ... Have anyone used piezo electric material to ... How about placing a piezo disk under the paper stack with the piezo wired as ... a piezo sensor is a "change" sensor: ...
    (comp.arch.embedded)