Any sportsman, mountaineer, fell-walker, soldier etc can tell you that a dry mouth is a poor indication of dehydration. My idea is a wearable alarm that indicates you are dehydrated. My wife bought a high-end set of bathroom scales not so long ago, that tells you (as well as weight) your fat content (weight and percent), BMI and water content (percent). It is the water content I am interested in. I am not proposing a new technology, just a new application of an existing one. The dehydration verifier would have a couple of skin-contact sensors, a small processor that learns your average hydration level, and an indicator that alerts you when your hydration level falls out of the programmed acceptable range. A sportsman would then know it is time to neck some more of his isotonic lucozade, whereas the rest of us will know that it is time for a cup of tea and a HobNob. Boss: The oily water separator has broken down and the bilge tank is overflowing. Quick. Quick. Employee: Sorry Boss, my dehydration verification alarm has gone off and I need a cuppa. Boss: Good idea, I’ll have two sugars in mine.-- skegger, May 15 2009 //The dehydration verifyer would have a couple of skin-contact sensors
Will this work? Explain more about this, Harry Potter.-- leinypoo13, May 15 2009 Well the bathroom scales have two metal strips so that each foot is in contact with one of them. I suppose the measurement is based on conductivity. That being the case, the skin-contact sensors could not be connected too close together, otherwise your sweat would create a false reading.-- skegger, May 15 2009 + I think getting your weight would be necessary for calculating the water content.
The machine (gets your height right?) probably calculates your skin amount for your height, gives a constant for the skin resistance including organs and what not. Any increase from that presumption is calculated to be % fat.
From that you get BMI and another calculation of whatever left over is "water weight".
Since , I think that the water content calculation is a function of the resistance changes induced by "fat", I don't think it would work in this scheme.
Indeed your electrodes would have to be placed further apart, weight calculated etc. Perhaps in each shoe?-- leinypoo13, May 15 2009 While in hospital a nurse once pinched me (oo-er)... in the hand as a test for dehydration. The idea was to look at the skin elasticity. If it took too long to snap back into place then it was a sign you were dehydrated. Perhaps skin tension could be used in some kind of sensor?-- Jinbish, May 15 2009 Shoe sensors. Not that appealing, but ok. I take your point [leinypoo] about multiple calculations. I think the way to make it workable would be to have personalised devices where your statistics (height etc) are programmed in. I was hoping for a much simpler device than that though.-- skegger, May 15 2009 //I was hoping for a much simpler device than that though.
It's entirely possible (probably IMO, it has too) that dehydration changes skin resistance osmotically in epidermal cells, but to what extent it affects resistance as per a livable amount of dehydration (milli-microohms?) and the engineering it takes for a public product would be significant.-- leinypoo13, May 15 2009 Could one find a way to use thirst as an indicator of dehydration?-- MaxwellBuchanan, May 15 2009 As far as I know, by the time you are thirsty, you may have been dehydrated for hours.-- Jinbish, May 15 2009 Sorry [MB] but that is as unreliable as my proposed device seems to be. HobNob anyone?-- skegger, May 15 2009 How about an armpit saline/moisture sensor?-- 2 fries shy of a happy meal, May 15 2009 random, halfbakery