You are reading a single comment by @user96191 and its replies.
Click here to read the full conversation.
-
Thanks for your feedback, Gordon!
The watch case looks nice, so we may give that a try. If so, we'll let you know if we need a spare plastic case.
The DS18B20 TO-92 temperature sensor looks promising.
Turning it off between readings will indeed extend the battery life. The monitoring should only be necessary for some days in a row (and perhaps even only during the night time), so the battery should not be a problem.
We'll discuss the possibilities and let you know the outcome.
Thanks again for your help!
user96191
Wow, that's a great use.
With the Pucks, there is a 'watch case' by @MaBe that can be 3D printed: https://www.thingiverse.com/thing:2095572
That could either go around her wrist, or you could sew it on. I do sell spare plastic cases so you could also just drill some holes in a normal one and sew through if needed though.
Actually measuring the temperature could be a bit prone to error. While the Puck can measure temperature pretty well once you calibrate the offset (eg, take a temperature reading with it at a known temperature) the sensor is on the chip so won't directly be in contact with your grandchild's skin and would I imagine take a while to respond to any temperature changes.
You could add something like a DS18B20 though - the TO-92 versions are the size of a small transistor, respond quite quickly, and are calibrated and pretty accurate. You could just wire one onto the Puck and cut a small hole in the case so it was extremely close to your granddaughter's skin.
The only gotcha is the DS18B20 draws around 1mA when on, so would flatten the battery in ~7 days. You'd just need to power it from an IO pin so you can turn it off between readings.