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Have a good idea for a new product for SFE or Olimex? Let us know!
By fuzzoli
#104974
Are there any simple (i.e. cheap) sensors that, along with some uC intelligence, determine that someone is shaking it? I seem to remember a sensor a while back that had a little steel ball inside it along with several wires. A simple program could then be written to figure out when a "shake" occurred.

Anyone have ideas? I'm looking for small and low cost.

Thanks,

-Frank
Holland, PA
By Philipf
#105014
A small spring. My kids have countless toys that operate this way, alot of the time they have 2 springs, 1 either side of the board.
By mikeselectricstuff
#105488
How low cost? Accelerometers are pretty cheap nowadays.
A piezo element with a weight on is another possible.
By dez.ellis
#105500
fuzzoli wrote: A simple program could then be written to figure out when a "shake" occurred.

Anyone have ideas? I'm looking for small and low cost.
Low cost? Depends on your budget but they do exactly what you require. The first link is to the SQ-SEN-200 and similar the second link is to an algorithm to help determine the level of activity that you wish to detect.

http://www.signalquest.com/product_selection.htm
http://www.signalquest.com/datasheets/D ... orithm.pdf
By RonnyM
#105553
The Signalquest devices are small, easy to use, and have a current draw less than 1uA. They are a few bucks a piece though. I have used dozens of them and they are reliable.
Ron
dez.ellis wrote:
fuzzoli wrote: A simple program could then be written to figure out when a "shake" occurred.

Anyone have ideas? I'm looking for small and low cost.
Low cost? Depends on your budget but they do exactly what you require. The first link is to the SQ-SEN-200 and similar the second link is to an algorithm to help determine the level of activity that you wish to detect.

http://www.signalquest.com/product_selection.htm
http://www.signalquest.com/datasheets/D ... orithm.pdf
User avatar
By Conrthomas
#106121
Expanding on what Philipf said...
I would imagine a spring from a ballpoint pen on a metal rod, with a spacer between the rod and the spring so that when the spring shakes, you make a connection...also look at some pinball "knock sensors" or "tilt sensors" for good electromechanical ideas. I have seen the spring and rod setup in a couple kids toys before, and they're fairly reliable.