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Ask HN: What do you do with your Raspberry Pi?

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Re: Ask HN: What do you do with your Raspberry Pi?

#771
I used a Raspberry Pi to solve the problem that the trash can in front of the building where I lived was often overflowing when I tried to take out the trash:

I connected a 20x4 character LCD to the Pi and put it next to the bathroom mirror. The display displays some useful info: - Estimated garbage can levels (interpolated based on the trash calendar) - weather forecast - cryptocurrency prices

So when I notice that the trash can level is low I can take out the trash without troubles.

(These days I use my Pis for more simple things like RetroPie+Kodi and PiHole)

Re: Ask HN: What do you do with your Raspberry Pi?

#773
I'm still using an old 1B (512MB version) for Kodi, almost on a daily basis. Playing back stuff from an NFS share. I'm limited to 1080p but that's still fine with me, I'd need a TV upgrade first anyways.

It's showing its age though, and I had to hack up some stuff to use it properly:

I'm controlling Kodi via Yatse (Android app), and mostly just use the file mode to browse Movies and TV shows. I have them sorted and named properly anyways so that's not that much of an inconvenience to me. Using the fancy views that show artwork and IMDB metadata is still working but a little to slow.

But even in plain "file mode" Yatse was a little to slow and sometimes timing out when listing directories with 200+ items. This is where the hacky stuff comes to play: I built a simple proxy that intercepts the requests from Yatse and modifies them, namely, when Yatse is listing a directory it sets some field in the JSON that says "media type video" for example, when browsing for videos (forgot what the key is called exactly; currently at work). So I simply strip that key entirely from the request, and now listings take 1-2 seconds for large directories.

While I was at it I also started to intercept links to youtube videos and instead call youtube-dl to download them first and then have Kodi play them back via NFS. This way I get 1080p instead of just 720p and also have a history of everything I watched on YouTube, in case I can't find it anymore, or it gets deleted etc. It's pretty brittle since it doesn't properly track state or prevent you from triggering a second download while the first one is still active, also if you request a 50min video it will take a while until playback actually starts, since it needs to download it fully first. But at least it recognizes if a video has already been downloaded and just starts playback instantly. Turning this into a proper project is on my TODO list, but that list is mighty long.

Re: Ask HN: What do you do with your Raspberry Pi?

#775

2 Pis for dealing with ADS-B (airplane data), one for 1090Mhz, the other for 978Mhz. I could run that on the same one, but seemed easier to just split them up given some of the software is a bit picky with device IDs. The 978Mhz is much quieter than the 1090Mhz, so I also run a private SpyServer ( https://github.com/lloydpick/docker-spyserver ) for listening to radio transmissions. 1 Raspberry Pi for a running a very…

This reminds me of this project I saw on twitter a while ago where a small arduino with a motion sensor would play the Seinfeld bass riff every time someone entered a room.

Re: Ask HN: What do you do with your Raspberry Pi?

#776
post #732

I started a company that constructed booths which used 70 accurately sync'd Pis with custom PiCams (fitted with lenses) to take pictures of human subjects, for turning them into avatars like this: https://sketchfab.com/3d-models/pete-swagger-walk-a55d807de1... At the beginning of the project, I'd barely powered up the Pis I had collecting dust in my drawer. By the end, I was a legitimate domain expert in several nich…

Could something like this be used for synchronization in such a scenario? https://ncase.me/fireflies/

I think the problem here is not that the clocks are out of sync, but rather that the actual clock frequencies are voltage-controlled.

With the firefly analogy, it's like having one firefly flashing at 1.73513x (random number) faster than it's neighbor - can't easily have them persistently synchronized.

Re: Ask HN: What do you do with your Raspberry Pi?

#777

I used my Raspberry Pi 3 B+ to control all Fish tank equipments remotely. We live in a city (Chennai, India) and my family usually goes to our native for 2 months every year during summer vacation. During these times, it find it very difficult to manage the equipments. The Raspberry Pi controls 2 Lights, 2 Filter pumps, Cooler, Fish feeder, and CO2 cylinder. Am planning to attach a camera and some sensors to the syst…

I always wanted an aquarium and this was the sole reason I never got one, thanks I'll look into it. Can you tell what are your equipements and whats the setup like? (sorry, if already mentioned in github I can't open at work)

The config file in GitHub already has the schedule for each component.

Equipements: 1. Lights 2 (One for plants and another colour LED light that came by default with the tank) 2. Filters 2 (One Canister filter and another top filter) 3. Cooler 4. CO2 cylinder 5. Fish feeder (Built myself)

Currently, some equipment are always ON but planning to allowing to control remotely in future for triggering automated maintenance routine.

The Pi is controlling an power extension box using a 8 relay module.

Re: Ask HN: What do you do with your Raspberry Pi?

#778

I started a company that constructed booths which used 70 accurately sync'd Pis with custom PiCams (fitted with lenses) to take pictures of human subjects, for turning them into avatars like this: https://sketchfab.com/3d-models/pete-swagger-walk-a55d807de1... At the beginning of the project, I'd barely powered up the Pis I had collecting dust in my drawer. By the end, I was a legitimate domain expert in several nich…

What you call UBEC is just a switch mode DC-DC buck converter. They are used everywhere in electronics, and you could probably save money buying general puprose 5V buck converter modules instead of modules made specifically for RC. Anyway, that's very interesting info about supply voltage affecting Raspberry Pi speed and timekeeping, thanks!

Re: Ask HN: What do you do with your Raspberry Pi?

#779
post #641

I have 13 in service right now: - Outdoor irrigation control via OpenSprinkler Pi: https://opensprinkler.com/product/opensprinkler-pi/ - Z-Wave home automation via ZWay: https://z-wave.me/products/razberry/ - 2 Custom HAVC thermostats using: https://github.com/jeffmcfadden/PiThermostat - An NTP server with GPS attached for a time source. - 2 for weather monitoring (one directly attached to sensors, one that aggregate…

You are a kindred spirit. I have: 2 pi NTP servers - one running a GPS hat + PPS wired up, one using a USB gps receiver. a "workhorse" pi - 2 wired ds18b20 temperature sensors, cron jobs, email generators, weather page generator, connectivity monitor. One pi running piubos + nextcloud. One pi running as a clock. One pi running as a wireless temperature receiver. a few floating pis running media center or retropie or…

Just curious, what kind of firewalls are you running?
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