The problem I try to solve Looking for a temperature sensor using Bluetooth that can report to Home Assistant through my phone when out and about and preferably (but not necessarily) report through my ESPhome BT-proxies at home.
Background I have a 3 year old son with type 1 diabetes. As a result I always have to carry insulin, a temperature sensitive medication. The vials are stored long term in the door of my fridge together with a ZigBee sensor monitoring the temperature of the insulin. If it freezes the Insulin denatures and won’t have any relevant effect if used. The vial that I carry with me will last for around a month as long as it stays above 0 °C (and under around 25-30 °C). My son uses a CGM/pump-based system, creating a BAN that also involves his smartphone. This means that phone is always near the vial and could record temperature (and send telemetry data) continuously, even away from home. I want to use a temperature sensor to identify spoiled medication due to thermal conditions even when my son leaves our home.
My current (imperfect) solution I currently deploy a solution where I use a Meshtastic node with a BME280 sensor. It reports through the mesh to a node at home. This node uses MQTT to talk to Home Assistant. The problem with this system (although nice being totally independent from the Internet) is limited coverage of the surroundings as well as very infrequent telemetry reporting to not overload the common mesh in my city.
Is there an easier solution? Preferably one that uses the smartphones bluetooth (BLE?) and reports back over the Internet.
I know this is technically not an answer to your question, but as a fellow T1 diabetic (for 20+ years) and dad to diabetic child (currently 2½ years old): Is this something that regularly happens to you? I don’t know where you live, but in over 20 years of being a T1 diabetic I never had a vial of regular insulin go bad. I don’t have to worry about the cost of insulin as my insurance would without any questions replace any medications gone bad for me, but I understand that this is a luxury not everyone shares.
There are products (but I have to assume you are aware of this) that can help you with the temperature safe transport of insulin for everyday use (basically insulated pouches with an integrated cooling pad). That may be something you can look into if this is something you need to worry about.
Thanks for the answer! I’ve yet to experience ruined insulin due to thermal conditions. My son recently debuted but will soon go back to kindergarten and they will need to handle the medication during the day. Both me and my wife are medical doctors but the staff at kindergarten are not well experienced with medicine and may accidentally leave it outside for too long.
In Sweden where I live the medication and equipment is free so that’s not the reason to watch the temperature. Looking outside my window right now there’s snow everywhere and -19 °C. In the maternal line of my son T1D is common and frozen insulin is not too uncommon, heat damage not a problem.
I realize this is not of great concert but I’d like the challenge of creating a monitoring system.
I totally understand your concerns. We just don’t have such cold winters here in Germany. And I also understand your point more (also after having read your other comments). If the insulin vial in question is a spare it will most likely not being noticed if it freezes until it is needed.
In theory you could use the Bluetooth sensors of the companion app which can be used to detect BLE beacons. But that would require a special Bluetooth device that activates once a threshold temperature has been detected. Maybe such things exist (I’m thinking of (food) supply chain monitoring), but I am not aware of any.
It’s always hard to describe the use case in enough detail without being so boring that other people will read to the end ;)
Didn’t know about the companion app being able to detect BLE beacons. I have never heard about a beavon coming to life if outside set twmperature range. If such a product were to exist it would be great.