Sip-and-Puff (SNP) controllers are nothing new – you’ve probably seen one in action yourself. SNPs are often seen on electric wheelchairs and allow individuals who can’t use their hands to control their wheelchairs (or whatever else) by either “sipping” (inhaling) or “puffing” (exhaling) into a straw. Depending on how hard the individual inhales or exhales, it makes the wheelchair respond differently. It’s a pretty amazing technology that has changed the lives of millions of people for the better.
If you are counting on a sip-and-puff switch for something like controlling a wheelchair, it is probably in your best interest to have a professionally built one that can be perfectly calibrated. But what if you want to build an SNP controller for something else? SNP controllers can run upwards of $400 and if you want to, say, build an SNP controlled joystick for a video game or some other use, buying an actual SNP might be cost prohibitive.
For more detail: Arduino Controlled Sip-and-Puff
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