Ask HN: What cool projects do you suggest I build with a Raspberry Pi 2W

24 points by vivegi ↗ HN
I just got a Raspberry Pi 2W. What are some cool project ideas for building with it?

19 comments

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I want to put one on a model train, with camera; possibly with pan & tilt on the camera. have it stream video, offer camera controls, maybe put audio output on it.

I wanna do this in N scale.

I doubt i'll ever get the full vision of the idea realized but i've got a few seconds of footage from train POV as it runs around the table from a taped together prototype test and that may be enough to keep me interested in the idea.

If you want a simple off-the-shelf solution, Eachine TX06 or similar 5.8GHz FPV cameras + Skydroid receiver are cheap (~$15 + $25 shipped) and offer decent image quality (PAL or NTSC resolution) that you can view on many phones.

- https://www.youtube.com/watch?v=nrK3tGIC33E

- https://www.aliexpress.com/wholesale?SearchText=Eachine+TX06

- Eachine TX06: https://www.aliexpress.com/item/2255800455864759.html

- SkyDroid Receiver: https://www.aliexpress.com/item/2255800153959032.html

For pan/tilt, you could wire up a servo motor to an RC receiver.

Almost same question, but quite tangential: I'd like to have a plant watering system with least complexity involved. I would assume a fish tank pump plugged into any PC. The plugging part however is not quite-well thought out, neither the output to multiple pots. Could you suggest some ideas? Arduinos, valves, etc? The watering is not automatic and should happen with a push of a PC keyboard key.
I recommend you look into Blumats [1] - no electronics required watering system.

[1] https://blumat.com/

(comment deleted)
I’ve recently contemplated a submersible pump in a bucket (to limit the water in the event of a leak), and just using one of those $10 cloud-enabled switchable plug outlets, with fan-out drip tubing and a suitably-sized flow regulators going to each plant.

Eventually perhaps building in some moisture sensors and some pi/arduino logic to then control the pump.

You can get watering timers in home depot, you could try hacking one of those? The hard piece to get is probably the electronic valve.
The easiest solution would be to buy a smartplug and integrate it into one of the smarthome ecosystems like Google Home, Amazon Alexa, Apple HomeKit.

For a more DIY solution you can install Node-RED onto a Raspberry Pi for a GUI flow editor: https://hackaday.com/2020/01/15/automate-your-life-with-node...

Alternatively, if you'd like to do everything on the Raspberry Pi, use its GPIOs to control a relay module with optocoupler isolation (~$4) which can turn the pump on or off: https://www.aliexpress.com/item/2251832713449142.html

If you're more hardcore, you could flash a smartplug like Sonoff S31 with Tasmota and add rules that trigger based on various events (eg: timer). https://tasmota.github.io/docs/Rules/#rule-variables https://tinkerman.cat/post/sonoff-s31-now-serious

Buy a bunch of cheap sensors from Amazon and learn to interact with them. Learn what I2C is, and learn how to chain a bunch of devices together. Get a few relays or servos and you can learn how to start interacting with the physical world through machines. Find a recurring task in your life and automate it
Something like "The Clapper" but more elaborate, to scare away burglars

https://en.wikipedia.org/wiki/The_Clapper

I'm very anti "internet of things" but I used to wire that to an AM/FM radio and/or lamp so it would give the appearance of someone waking up if you jiggled the door handle at night, after one too many times exactly that happened when I was home.

(Just before I came to town a white woman had gone missing, so I was surprised at how many weirdos they let just wander around under the pretense they were selling magazines or Jesus or whatever.)

Out of morbid curiosity…what is the alternative to letting people wander around?

—edit—

And the doorknob thing, just balance an aluminum can on it so it makes a terrible racket if someone messes with the knob. Wakes you up, they’ll hear it and having a shotgun handy will make them seriously reconsider their life choices if it comes to that.

> Out of morbid curiosity…what is the alternative to letting people wander around?

Citing them for disorderly conduct, ticketing them if they blow a stop sign or something, or otherwise making them feel unwelcome if someone reports they're literally wandering around trying doorknobs under the pretense they're selling something

+100

There’s something so fun about using small, cheap, and efficient hardware for interacting with the real world.

It’s also a good stepping stone to the world of esp32 (which is more suited to most tasks like this, IMO).

Warning to OP: it can get really addictive! Next thing you know you have entire collections of random microcontrollers, SBCs, and drawers full of relays, sensors, servos, etc!

Attach a battery, a camera, a 1 inch screen and a big button -- make a doorbell.
Automate parts of your home life with Node-RED:

https://hackaday.com/2020/01/15/automate-your-life-with-node...

Alternatively, if you are interested in making or playing back music, one idea is to turn the Raspberry Pi into a MIDI synthesizer:

MiniDexed: 8 DX7 Tone Generators

- https://github.com/probonopd/MiniDexed

- https://www.youtube.com/watch?v=Z3t94ceMHJo

MT32-Pi: Roland MT-32 emulator

- https://github.com/dwhinham/mt32-pi

- https://www.youtube.com/watch?v=vaSD_wbzJRw

Optionally, buy a PCM5102/PCM5122 or ES9018K2M I2S DAC to improve the output sound quality:

https://raspberrypi.stackexchange.com/questions/76188/how-to...

PCM5102 (~$7): https://www.aliexpress.com/wholesale?SearchText=PCM5102+DAC

ES9018K2M (~$12): https://www.aliexpress.com/wholesale?SearchText=es9018k2m+i2...