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I need to make a "notification system" for a pass door in a medical facility.?
There is a little 3x9 tray inside, so I've thought about some type of momentary switch with a little LED light and a battery, but I'm not sure how to fabricate it.
2 Answers
- ?Lv 75 years agoFavorite Answer
One simple way would be to make a scale that weighs the items on the 3 x 9 tray. If the item weighs more than usual, have a light come on indicating a specimen is ready. You can build one out of an Arduino, a hx711 amplifier, a 1 Kg load cell (or 4 load cells depending on your requirements), an led light, and 5 volt power supply. The total cost should be less than $15.00 if you buy direct from China.
- ?Lv 75 years ago
Since you have no idea how to design and make it works, why taking this project.
This device existed in market, most store uses it at the front door. Why bother to make it.
