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Comment by minimalist | Hacker News Reader

Andreas Spiess' recent video [0] covered some milimetre-wave radar chips whose application includes presence detection at a distance (including if the bed is occupied).

Does anyone know of any bed automatable bed heating/cooling solution (DIY or otherwise) that can work offline of with Home Assistant? I had my eyes on E*ght Sleep but it looks like a lot of the functionality is behind a subscription wall [1] and the device is very chatty [2] and I haven't been able to find any API reverse engineering / firmware mods.

[0]: https://www.youtube.com/watch?v=s-GzUTyIH9c

[1]: https://old.reddit.com/r/EightSleep/comments/1248wgz/buyer_b...

[2]: https://old.reddit.com/r/EightSleep/comments/185cgm4/pod_3_t...

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On the bed heating/cooling front, you might try the Ooler series from sleep.me

The older generation Oolers use bluetooth and there are a fair number of integrations including an [MQTT bridge](https://github.com/turmoni/ooler-mqtt-bridge) and a [HomeAssistant integration](https://github.com/PostLogical/ooler).

I'm less familiar with their latest generation which uses WiFi, though there [seems to be an API](https://docs.developer.sleep.me/api/ ) available for it now.

I looked at mmwave stuff for my own setup but I just couldn't get over it triggering on things like ceiling fans etc moving, curtains rustling.

I think the idea of presence detection is such an interesting problem, really an AI camera is the best solution but nobody wants cameras all over their house. There's also thermal imaging with sensors like MLX90640 which is a very low res thermal sensor.

Seems to work pretty well for the most part, had a bit of a play with it but not actually built something to be put in the home yet but the only drawback is static heat sources like radiators obscuring moving heat sources like a person.

there's bedjet. i find that it doesnt work well with adjustable beds though because when you raise the leg part up, the bedjet hose thing tends to slip off.

https://github.com/pjt0620/Home-Assistant-Bedjet/

I suspect the sleep.me chilipad systems (ooler/dock pro) would work pretty well with adjustable beds since they just run a pair of insulated water hoses to a capillary tube network in a mattress pad. Further, if the hose routing didn't work for you out of the box with those you could DIY something else pretty easily since they use off the shelf connectors (https://www.cpcworldwide.com/General-Purpose/Products/Multil...)

Does anyone know if mmWave could differentiate between my cat and I?

In theory, but probably not in practice. The fancy non-metal-detector airport security scanners use mmWave to detect object through clothing, so the light itself capable of producing high-resolution images. However, cheap home automation sensors are probably not imaging, so you're probably going to be stuck with a single depth measurement.

HomeSeer manufactures a Z-Wave millimeter wave radar sensor that uses imaging techniques to detect motion in specified zones, and they intend to release pet differentiation as a firmware update. I'm seeing enough negative reviews of how it works in practice that I haven't dropped the money on one, but I'm hoping that the technology will improve quickly. It's only $59 too, which isn't much more than PIR Z-Wave sensors. Maybe I will buy one to try out...

Possibly at shorter ranges. Those devices are essentially ‘bag of water’ detectors. You can get some data out of most of them that pertains to distance and approximate size of the ‘bag’.

They generally suffer from exact counts of objects. 2 people close to each other will read like one large person. A large cat close to the sensor could read like a large human at a greater distance.

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