This is a cool scale mod. The Weight Logging Bathroom Scale saves the the time stamped weight for each use to an SD card. This allows the data to be plotted and analyzed. The method that the weight was taken from the existing digital scale platform is real interesting. The original LCD data lines were snooped on to determine what value is being displayed!
Thanks Jorge.
"First I thought that I could read the sensors and got an analog voltage relative to weight but I couldn’t find a way to do it. Next a friend at work give me the idea to try read the signals that went to original LCD, and it was a simple and easy way to have what I need 🙂 The original LCD have 15 pins, 3 backplanes and 12 segments. I did understand how the LCD signals works reading this application note. The segments signals have voltage that can be read directly by the LPC2103. The backplanes signals can’t be ready directly by the LPC2103 (I think) and then I made a very simple voltage detector using a LM258 opamp so I get a "trigger" signal every time the backplane signal get near is maximum value."
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oh no, no, no, no, no! I really don’t need something to remind me that I’m not losing weight. The only reason my scale isn’t covered in dust is because my daughter uses it. Though I don’t understand why, since she weighs 115lbs with wet clothes.
Very nicely done tho, even if esthetically rough on the eyes. nice tool for weight loss tracking, or maybe to shame you out of the cookies you really want to eat.
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It is a MASS logger actually.
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Hack off the weight! Just program in what the diet promises.
No exercise and I can still “lose 10 lbs/week” in only 20 weeks I’ll be weightless and can fly to work!!!!
Few lines of code (no reality required) = happiness
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Pete: No, the scale measures weight, the force applied to it.
If it could somehow magically measure mass, it would display the same thing for a given mass on earth and on the moon, without adjustment.
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Anon: Agreed, I guess I got ahead of my self and didn’t fully explain what I meant. And that is that “weight” is meaningless without supplemental information such as local gravity.
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@Pete(2) wahahahahahahahahahahaha =p
@Anonm,@Pete(5), i think you’re both right and wrong! If you go really down deep into the scale measurement system, it actually measures voltage. Everything else is conversion, manipulation or display, according to Doebelin! (Measurement Systems : Application and Design, by Ernest Doebelin)
Mass*Gravity(Weight)=>Deflection=>Resistance Change(Strain-gage)=>Voltage Change(Wheatstone bridge)
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Its name is funny
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