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Ask HN: Most interesting tech you built for just yourself?

1901 points l2silver | 3 comments | 27 Apr 23 15:04 UTC | HN request time: 0s | source

Maybe you've created your own AR program for wearables that shows the definition of a word when you highlight it IRL, or you've built a personal calendar app for your family to display on a monitor in the kitchen. Whatever it is, I'd love to hear it.
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steve_adams_86 ◴[28 Apr 23 06:27 UTC] No.35738121[source]▶
I built myself an automated hydroponic grow tent.

It measures and corrects pH, electrical conductivity, oxidation reduction potential, temperature of the air and water, water level, and humidity. It also automates pumps, lights, and fans (I know people normally advise against this). None of it is particularly sophisticated, but I’m really proud of it.

I initially used a deep water culture and later moved on to the nutrient film technique. It produces a lot of greens and herbs — way more than I ever expected — and it’s remarkably hands off. I recently left it to do its thing for almost 3 months before I had to intervene, and the problem wasn’t the water, nutrients, or the system failing explicitly. The plants just got too big for their channels and as they became stressed, they developed some pest issues. It was such a cool and empowering experience to see real world automation Just Work.

The whole thing is powered by an Arduino Nano RP2040 Connect. It’s a great little controller.

I’m currently designing my first PCB to consolidate the system onto a single board so my friends can easily build their own. It’s not extremely cheap, but it’s not too expensive either and you get a tremendous amount of food from it. It’s such a fun hobby.

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Aerbil313 ◴[28 Apr 23 07:19 UTC] No.35738466[source]▶
I’m very interested, is it possible for you to open-source it? Also, what are its absolute dependencies? Does it depend on daylight? Fresh air from outside? Stored chemicals? Is water/air recyled? What is the reason behind you making this? I’m preparing for Collapse and want to do such a thing soon. If you can open-source it, it would be very cool and helpful.
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uuuuuuuuuuuuuuu ◴[30 Apr 23 07:16 UTC] No.35760325[source]▶
The main resource that you need in steady state is always electricity. For light, heat, pumps. And a lot of it, especially in winter time. The rest is mostly closed loop.

If you are preparing for Collapse, ensure you have multiple independent sources of electricity available. Solar, hydro, wind. If you are in a city you are better off with a storage room full of canned food since your hydroponic plants wont give you much food after power goes out.

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1. Aerbil313 ◴[30 Apr 23 19:26 UTC] No.35765800[source]▶
Thanks. I don't want to be anywhere near any population centre, the biggest threat by far is masses of hungry people imo. I'll build an open-source food production system with only dependency being sunlight later this year inshaAllah, everything else will be closed loop. I don't think any amount of canned food will cut it either, this is Collapse of the entire civilization we are talking about. Maybe 10 years of canned food will let me and my family ride out the initial population decline, but there's always the possibility that armed groups will take it, not to mention I can't not share it with those in need (read: everybody) as a muslim.
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2. steve_adams_86 ◴[01 May 23 03:43 UTC] No.35768870[source]▶
I can’t not share with others, either. To me a collapse means bringing everything I’ve got to the table for my family and community — no hoarding, no hiding. I really believe these skills (hydroponics, basic automation, growing food) will matter if something happens.

People who can help and provide actually stepping up to support less able people is the best thing we can use to prevent real catastrophe, I think.

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3. Aerbil313 ◴[01 May 23 15:39 UTC] No.35774371[source]▶
> to prevent real catastrophe

I guess we'll agree to disagree on this, I don't think we can prevent real catasthrophe. We can prevent some (relatively small) amount of suffering though, and all that matters is we do the best we can. A mind-opening must-read imo article on Collapse: https://medium.com/@CollapseSurvival/overshoot-why-its-alrea...