Digital medicine scale recommendation - Page 1
Forum section: electronics / projects

author: waoj
author_rank: Contributor
timestamp: May 21, 2025, 03:53:45 am
content: I'd like to automate the inventory and measurement and reminders for medicines my mother in law regularly takes.My idea is to keep all medicines on a scale and use software to monitor the weight every second. When it's time to take a medication it will chime repeatedly and then wait for the weight to reduce as she picks it up.If the weight change is implausible for the correct medication then it will beep angrily. If it's plausible then the reminder chime stops. When the weight goes back up, it will calculate how much she took based on the weight difference and record in a csv the amount and time.She's not senile. But I just want to keep detailed records without burdening her to write it down all the time. And one med is an eye drop which makes it hard for her to see for a few minutes anyway.So I'm looking for a recommendation for a "medicine scale" (meaning it can measure micrograms), that has a digital output of some sort.There are myriad options super cheap that just have a digital display. But the ones with a serial port I've seen are Huge Industrial looking things for over a hundred dollars.Is there something with wifi or BT perhaps that's small, pocket size? Or micro/c USB?I've also given thought to using a cheap camera (wyze v2 with rtsp fw) and computer vision to read the scale and keep snapshot of the meds themselves too. That might be the better option for photographic certainty and just put the scale and camera inside a box or frame of sorts. Cameras use way to much power to be battery operated though so that's a downside. But so does Wi-Fi basically....

author: Doctorandus_P
author_rank: Super Contributor
timestamp: May 23, 2025, 06:36:50 pm
content: Years ago I had medication I had to take twice a day, and I'm also a bit forgetful, so I made a pill timer for myself. I don't like noise, so I just used a micro switch and a LED. The LED goes on when it's time to take the medicine, and it goes off when I lift the bottle from it's holder. And this was good enough for me. Years later I changed that to once a day for other medicines. And I trust myself enough so that once I redirect my attention to the medicines, I take them all, and in the right quantities.I also sort of like the commercial pill boxes. They have for example a weekly grid. Sometimes one week, sometimes 4 x 7 for a month. You fill it up once a week (or month) and you can see in the box whether you've forgotten a day or not.More invasive options I only see as an option if it's really mandatory, such as slowly progressing alzheimers.If you want to go the weight scale direction. I would start with a cheap scale from Aliexpress, and put in my own microcontroller. If battery power is a wish, I would probably put a microswitch on it too, that is activated by removing the bottle. This wakes up the uC from deep sleep, and only then it starts monitoring the scale. This way it can run multiple years on a set of two AA's. (Size is not a big constraint for such a device, you can even make it look like nice and put it in a prominent place.I don't like LiPo because of their fire hazards when abused, misused, or when electronic fails etc. LiFePo is quite nice. It's voltage is also a bit lower, and this makes it directly compatible with 3V3 logic. Low power design is an art in itself, and just the idle current of a linear voltage regulator or a leaky electrolytic capacitor can decimate battery life. Most 5V (capable) micocontollers also keep on working to below 2V so they can make use of the full capacity of either LiPo or LiFePo. When you use rechargable batteries make sure you have an under voltage cutout protection and decent charging circuit. a single 18650 cell (or such a bag battery) can probably last several years on a single charge, but topping it off once a year is a simple and solid strategy.I have an ebook reader and it's battery behavior is extremely annoying. At some point it starts begging for a charger, starts blinking the screen repeatedly on each page change (which wastes more battery current) and quite quickly turns off If I don't put it on a charger immediately. Having it give a single notification when the battery is around 30% would give me enough of a reminder to put the thing on a charger at the end of a few hours of reading without being tethered to a wall. It's a really stupid design flaw.