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Building an occupancy sensor with a $5 ESP32 and a serverless DB

matthew.science

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Re: Building an occupancy sensor with a $5 ESP32 and a serverless DB

#81

Post by lostapathy »

szundi wrote: post #78
lostapathy wrote: post #53

Earlier quoted context omitted.

As somebody else mentioned, you can hire it out. There's a lot of files running around with existing models for common projects, so you probably don't need to design your own enclosures a lot of the time unless you want to. And printers have gotten cheap, like $99 gets you a jumping off point into the hobby.

$99 is just enough to jump into the hobby of fixing your printer all the time - and that's what hobbyists are actually looking for solving something would be like $700 calibrated out of the box, like the old prusa 3 something or the bambu p1something.

I'm well aware. I think of the $99 printer as a filter - either it's going to catch your interest enough to justify jumping to a $600+ printer, or 3d printing isn't for you and you aren't out much.

Re: Building an occupancy sensor with a $5 ESP32 and a serverless DB

#82

Post by jetbalsa »

filterfiber wrote: post #2

This is an excellent write up! > Seeed Studio XIAO ESP32S3/C3, WaveShare ESP32S3 Zero, Unbranded ESP32-WROOM with OLED, Orange Pi Zero W (untouched), Raspberry Pi Zero W (L->R, T->D) After testing all of these, the only one reliable to work for long periods of time (one month currently) was the XIAO ESP32C3/S3. I suspect they may be having power issues? For the ESP32's specifically I highly recommend adding a beefy c…

I'm a huge fan of using Alpine with the RPi due to reducing writes to the SDCard. it will only save data to disk with a lbu commit -d and by default boots into a kind of tempfs.

Re: Building an occupancy sensor with a $5 ESP32 and a serverless DB

#83

Post by Johnny555 »

davidw wrote: post #47
lostapathy wrote: post #45

Earlier quoted context omitted.

3d printed enclosure?

That sounds like one of those "I have a problem... now I have two problems" jokes. I wanted something simple and cheap and now I need to go deal with this whole other thing I don't know much about and either rent or buy into it?

If you're looking for an enclosure for your hobby ESP32 project, there are lots of off the shelf, small enclosures available:

https://www.amazon.com/s?k=esp32+enclosure

If you want to sell a more finished commercial quality project and don't want to print your own, there are places that will fabricate one for you (but in low quantities, having them 3d print it probably cheaper)

Re: Building an occupancy sensor with a $5 ESP32 and a serverless DB

#84

Post by morphle »

szundi wrote: post #75
morphle wrote: post #66

Earlier quoted context omitted.

As others point out: you could hire someone to do it. Based on my custom 1 cent ASIC (custom chip) I would design, test and build your (moisture or other) sensor for €3000 excluding tax and price of all the needed tools. Usually more like $6000 because they want to outsource all the problems (like mass production and sales) to me morphle@ziggo.nl if you want me to design it

Mine would be 0.3 cent per chip and would need $50k investment. Jokes aside, if you know how to design a custom chip for 3k USD, I would like to know about it.

it is not a joke, you can do as low as 1.10870 cent per custom chip or 2 cent per off the shelf chip. 0.03 cent is impossible, the minimum size of a chip is .625 mm2 and that sets the minimum price.

Designing one for $3K is possible because I already have a tested chip design that I just have to modify for you.

A master student project is usually a free design with a free tapeout at Google MPW, Mosys of Europractice.

I also design bigger chips and $500 wafer scale integration with 10000 cores : https://vimeo.com/731037615

Re: Building an occupancy sensor with a $5 ESP32 and a serverless DB

#85

Post by kube-system »

davidw wrote: post #57
lostapathy wrote: post #53

Earlier quoted context omitted.

As somebody else mentioned, you can hire it out. There's a lot of files running around with existing models for common projects, so you probably don't need to design your own enclosures a lot of the time unless you want to. And printers have gotten cheap, like $99 gets you a jumping off point into the hobby.

Do people not just sell like "complete package" things? The board in the article is $13.49 ( https://www.amazon.com/dp/B072HBW53G ). If you could get an enclosed, complete thing for $20, including the board and whatever you need for it to run, that'd be much less of a PITA than "brand new hobby" or "find someone to 3D print stuff for me locally and deal with that whole hassle".

The thing about enclosures is that they are pretty design dependent. Nobody knows what you are hooking up to your board or what the intended purpose is. Some boards do have generic type cases, e.g. raspberry pi cases.

Re: Building an occupancy sensor with a $5 ESP32 and a serverless DB

#86

Post by morphle »

davidw wrote: post #43

How do people "productize" their ESP32 projects? (Edit: not talking about mass-producing something, I just want a self-contained unit rather than a board with a bunch of wires sticking out) I see a lot of pages where they show some bare-looking board, but in the real world you want to package that up. If you're a software guy like me, you would likely prefer to pay a bit extra to just have that tidied up for you rath…

You shouldn't productise anything with ESP32, its just an overprized bloated hobby pcb, very unprofessional.

See my comment below on how to productize this: use a 4 cent off the shelf microcontroller on a 10 cent pcb or much better: make a custom chip with all the sensors on board but with $25K minimum Capex but tiny Opex

Re: Building an occupancy sensor with a $5 ESP32 and a serverless DB

#88

Post by landemva »

ThrowAway1922A wrote: post #69
j1elo wrote: post #64

Always surprised to see people running around with their Bluetooth needlessly enabled. Maybe I worry to much about battery usage, but I just got used to always enable WiFi, Bluetooth, or NFC, only at the moment of usage, and disabled afterwards.

I have a smartwatch and airpods, turning off Bluetooth would cause both not to work. I'm more surprised that anyone ever turns it off, battery use is negligible compared to the cellular modem as I browse the web/listen to music.

I use Bluetooth maybe once or twice a year because I don't want to be tracked everwhere. Wired headphones. Phone in airplane mode much of the day. I suppose I am a privacy outlier, and I'm also not a slave responding to calls/texts.

Re: Building an occupancy sensor with a $5 ESP32 and a serverless DB

#89

Post by morphle »

szundi wrote: post #75
morphle wrote: post #66

Earlier quoted context omitted.

As others point out: you could hire someone to do it. Based on my custom 1 cent ASIC (custom chip) I would design, test and build your (moisture or other) sensor for €3000 excluding tax and price of all the needed tools. Usually more like $6000 because they want to outsource all the problems (like mass production and sales) to me morphle@ziggo.nl if you want me to design it

Mine would be 0.3 cent per chip and would need $50k investment. Jokes aside, if you know how to design a custom chip for 3k USD, I would like to know about it.

if you like to know more about it: morphle at ziggo dot nl to make a video conf appointment and get a demo. Or ask email questions, but that takes more effort for us both.

Re: Building an occupancy sensor with a $5 ESP32 and a serverless DB

#90

Post by neilv »

Since this was done by a student at a university, and at some level this involves tracking people, that's an opportunity to ask a professor about what human subjects protocols you'd need if this was research.

(A professor might be easier to ask than the university human subjects board -- who might refuse to talk with you because this isn't under their jurisdiction, or might get alarmed because you didn't talk with them sooner.)

There might also be campus IT privacy&security policies that apply. Of course people are getting violated much harder by ordinary Web sites, apps, and IoT devices, but sometimes universities aspire to be better than the outer world.

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