this post was submitted on 24 Dec 2024
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homeassistant

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Home Assistant is open source home automation that puts local control and privacy first. Powered by a worldwide community of tinkerers and DIY enthusiasts. Perfect to run on a Raspberry Pi or a local server. Available for free at home-assistant.io

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Only Sensor (5, 4, 8-AQ, and 2-TH): The only DIY home automation sensor you'll ever need (lemmy-ui.nowsci.com:33443)
submitted 1 day ago by [email protected] to c/[email protected]
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Hey all,

A couple of weeks ago I posted my 3D printable pegboard organizers, and today I’m releasing the Only Sensor line of home automation sensors.

Fully free and open, complete with wiring diagrams, cases, component bill of materials, and instructions for assembly.

You source and build them yourself, with acquisition costs ranging from $2-$35 to build, and options for:

  • mmWave presence
  • PIR motion detection
  • Temperature
  • Humidity
  • LUX
  • PM <10µm AQI
  • PM <2.5µm AQI
  • PM <1µm AQI
  • NOX
  • VOC

All integrate with Home Assistant via ESPHome.

All the details can be found at: https://nowsci.com/only-sensor/

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[–] [email protected] 2 points 5 minutes ago

Cool. A few years ago I made similar sensors (but just PIR, LUX, esp8266 board, jumper wires, and some with ultrasonic proximity). Attached them to the wall with those 3m velcro things. ESPHome makes things so easy; didn't even have to write code. Hardest thing was designing and iterating over the case to get the tolerances just right.

[–] [email protected] 3 points 4 hours ago (1 children)

The neatest part of this is finding out about GAM.

[–] [email protected] 1 points 4 hours ago (1 children)

Hah, yea I released that at the same time as WinApps so it didn't get as much fanfare. Glad you like it!

[–] [email protected] 1 points 29 minutes ago

Pretty sweet script, I might fork and see if I can adapt it to my Forgejo instance.

[–] [email protected] 7 points 5 hours ago

This is some peak Lemmy. Thanks for the good work!

[–] [email protected] 12 points 10 hours ago (2 children)

Those dht11 sensors are garbage tho. Best case they are wildly off on their humidity sensor. Worst case they keep breaking and shows nonsense readings. I would recommend bme280 sensor instead. If you read about them you might see people complain that they are reading too high temperatures, but in my experience its because they are misconfigured. Default settings have a very high sampling rate of multiple samples per second that heats up the sensor a tiny bit giving you the offset. Lowering the sampling rate or turn the sensor off completely in between readings gives really precise measurements on both temperatures and humidity.

[–] [email protected] 3 points 4 hours ago

+1 on BME280 vs the DHT. I don't know why the DHT are so expensive, they're pretty bad.

[–] [email protected] 4 points 7 hours ago (1 children)

Yea I've considered recommending thr DHT22 instead, but I was trying to keep costs as low as possible, and honestly I've had pretty good results thus far (calibrating with other systems, anyway).

[–] [email protected] 8 points 6 hours ago (1 children)

Bme280 is actually just as cheap if not cheaper than the dht sensors. But its a fair point trying to keep the cost down. I definitely like that philosophy, but if the quality suffers too much it's just not worth the trouble. Keep up the good work. 😎

[–] [email protected] 4 points 6 hours ago

Oh good to know, will investigate!

[–] [email protected] 11 points 13 hours ago (1 children)

Very nice.

It's missing CO2, but those are expensive so that's understandable. If you need one of those, I think https://www.airgradient.com/ is a great choice.

[–] [email protected] 4 points 11 hours ago (2 children)

I've had another user say the same thing, so I've considered investigating CO2. What's the rationale to you for wanting it?

[–] [email protected] 1 points 10 hours ago (1 children)

I don't have HVAC, so I'm just using it to see when the air at my desk is getting stale so I remember to open the window. I mostly use homeassistant for the configuration, although I might also set up a notification at some point (I only got my sensor 2 days ago)

[–] [email protected] 1 points 7 hours ago

Interesting. The AirGradient sensors are exactly what I'm trying to avoid with the OS, considering their price tag. MH-Z19 sensors might be a good direction for me to go.

[–] [email protected] 9 points 11 hours ago (2 children)

Not speaking for Mr Lemon, but for me CO2 levels are an interesting metric to trigger my air exchanger / HVAC fan combo for in a given zone, since it indicates stale air in general.

[–] [email protected] 2 points 7 hours ago

Good to know, maybe I'll add a MH-Z19.

[–] [email protected] 2 points 10 hours ago

Same ^

CO2 sensor for me is the most important.

[–] [email protected] 5 points 15 hours ago (2 children)

you will need to update the firmware on the LD2450. You do this with a mobile app called HLKRadarTool

Does this seem sketchy to anyone?

[–] [email protected] 6 points 11 hours ago

It certainly did to me when I made these. I ended up using an old Android phone for that part, but many members of the ESPHome community working with these sensors use it and have never reported a problem. HLK are the original manufacturers of the LD radar chips.

[–] [email protected] 4 points 14 hours ago (1 children)

No, why?

[–] [email protected] 2 points 4 hours ago

Because DFU exists. We shouldn't need an idle Bluetooth radio and proprietary arbitrary code execution to update the firmware on a device.

There are so many unnecessary attack vectors involved in this process, it should raise some red flags.

[–] [email protected] 4 points 23 hours ago (1 children)

Man, I wish this had been a thing ~8 months ago when I was building these for my stuff.

....mine are awful, and these look awesome, so maybe it's time to re-do that.

[–] [email protected] 4 points 23 hours ago

Weellll... In usual fashion for my projects, I made these about that long ago, just tested them for a long time before doing the write-ups.

[–] [email protected] 18 points 23 hours ago (1 children)

If anyone like me is wondering what:

  • PM <10µm AQI
  • PM <2.5µm AQI
  • PM <1µm AQI

…means it’s air quality. These measurements are referring to different sizes of particulate matter (PM) and their corresponding Air Quality Index (AQI) value

[–] [email protected] 8 points 23 hours ago

Yup! The ESPHome config also converts these into a standard AQI that you're used to seeing.

[–] [email protected] 8 points 1 day ago (1 children)

Hey now! The only sensor I’ll need is actually 4?! /jk

This is awesome!

[–] [email protected] 4 points 23 hours ago

Thanks!

[–] [email protected] 7 points 1 day ago (1 children)

This is incredible!

[–] [email protected] 3 points 23 hours ago

Thanks!

[–] [email protected] 23 points 1 day ago (1 children)

Amazing! This is great work!

[–] [email protected] 5 points 23 hours ago

Thanks! They were fun to build and design for sure.