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Best Raspberry Pi Projects (tomshardware.com)
239 points by Zaplanincan on May 4, 2022 | hide | past | favorite | 67 comments


See also RaspAP - turns your raspberry pi into a wireless access point.

I have one setup in a Raspberry Pi 400 for when I travel - it's configured as a wireguard peer back to inside my home network so any devices I connect to it are being routed securely to there before out to the internet (and I can also access my network from the road, including backups and media).


I stayed in a hotel over easter, the wifi in the hotel did not allow outgoing ICMP, tcp/22 or udp on any port. The only traffic I could find allowed outbound was on tcp/80 and tcp/443

udptunnel did the job, although I had to tether off my phone to get the server up and running.


One of the recent ones I did was a Pi-KVM.

https://imgur.com/a/AVxuR0d

Im honestly considering deploying these at work to replace some aging (and expensive) dell, java based ipkvms. I like it enough i made a second one to attach to a small headless desktop. Mainly just as a cheap quasi-OOB management.

Mine use h.264/webrtc or html5/mjpeg and on one i even hooked it up to a smaller kvm to give me a 4 port switcher via the webUI. Pretty slick and all told was under $400 for a 4-port model. A single pikvm, including the case and everything was about 100 bucks.

With some systems (ie: supermicro) and a ribbon cable, you could rig up ATX controls as well.


On the subject of IP-KVMs, I miss¹ something that I can plug on the USB of several computers, and access them by the bare serial interface, without messing with video capture and peripheral emulation. It would be something much simpler than the things available today, even requiring less wires.

The main issue I see with it is that it would need to connect to multiple host USBs and only one client.

1 - I actually don't miss it anymore because I'm not in a situation to use it, but I used to miss it.


Not sure i follow.

In this case. Its basically a single USB cable and a HDMI/Video cable.

All the Mouse/Keyboard etc is emulated through USB. Which is pretty nice. That was the best part for me. And with modern standards the lag was noticeable, but minimal. That said, in my cases, im just using SSH or something anyway. This was more for outage situations, or in a situation where i need to make a BIOS change remotely etc.


Oh, you have 1 of those for each server, like a normal IP-KVM. So there's a network, a video and a USB cable for each server, plus the server cables.

It should be able to build a device where you use an extra USB for each server plus one network cable for each 4, 8, whatever (if you push it, your entire hack).

To use it, you would SSH into the pi, and use a command to get a server.

The serial interface is quite old, everything tends to be accessible there. But now that you mentioned, I'm not sure you can update the BIOS with it.


So you can do that if you want, you would probably need some USB hubs to accomplish, and probably a logical way to map out your serial connections, but it should be doable.

https://docs.pikvm.org/usb_serial/

Or in the case of how I did it, i setup a multi-port KVM, that allowed me to manage x number of devices (with video) from a single unit. In this instance, a serial connection was used from the pi to the actual KVM which allowed me to switch inputs etc, from the gui.

https://docs.pikvm.org/multiport/

https://docs.pikvm.org/ezcoo/

https://docs.pikvm.org/multiport/


If you want to monitor things around you, and you have an SDR dongle set up, rtl_433 is handy. I have a Pi 3 running it to graph temperature and humidity readings from a couple of remote-reading sensors, plus barometric pressure from a Sense Hat and voltage, load, and battery readings from my UPS. It will display selected readings on the LED display, but I mostly just let mrtg/rrdtool do its thing.

https://github.com/merbanan/rtl_433


My first thought was, "Why would I need SDR to read temperature/humidity from sensors", then I realized these are more like wireless weather stations.

Out of curiosity: why did you decide to purchase ready solutions instead of rolling your own using ESP32 for a fraction of the price?


These devices actually end up being kind of hard to engineer, measuring air temperature accurately especially can be kind of tricky. And then add in that for a weather station it has to be resistant to the elements and low power. Speaking from experience, you end up spending more money and a lot more work going the DIY route except maybe at the high end. You can get an Acurite temp/humidity/lightning sensor that is fine outdoors and batteries last for ages for like $25.

Not that there isn't value to rolling your own, just I wouldn't assume it's as cheap and easy as you might originally.


It's not likely going to be cheaper to roll your own once you add a case and weather proofing and battery handling. These things can be had for as cheap as $15 on amazon, https://www.amazon.com/Crosse-Technology-308-1409WT-CBP-308-... or even down to $5 on aliexpress, https://www.aliexpress.com/item/1005003408554165.html

Along with that using 433MHz means that there's a much longer range, and they generally also have much lower power usage compared to doing wifi, which makes the batteries last a lot longer.


Not the person you replied to, but someone who did the same thing:

Most of the things inside my house are ESP32 or zigbee things I put together myself. Things that go outdoors, though, I'm much more likely to purchase an off-the-shelf solution for longevity's sake. Especially if the whole point of the item is to be rained/snowed on, be left in direct sunlight, and so forth.


You can always build a tiny little house for your outside ESP and leave it outside.


Yeah, mine's under a deck, in a travel soap dish with holes drilled in it. Works great! Power for that one is one of those little solar panels with a micro-USB port on it, used for battery-powered security cameras.


Love that! Battery backup for night & downcast days?


Yes, I have a 2200 mAh 18650 cell in there too, which the panel will mostly keep charged. In the darker, cloudier winter, I swap in a battery and recharge manually if it's not keeping up.

Running on an Adafruit ESP32 Feather board, it wakes up, sends its current readings over Wi-Fi to an MQTT service (that is on a Raspberry Pi), and goes back to sleep for 10 minutes. A little daemon running saves to Sqlite database, and another ESP32 unit inside has its own sensor, as well as displaying both (outside pulled from MQTT).

I've got some pictures and such, though haven't quite gotten to the much-belated blog post yet.


> haven't quite gotten to the much-belated blog post yet.

Thanks for the preview. Looking forward to it.


Thought about getting a bigger solar panel for those cloudy days?


Cloudy season, more like it, BC coast. ;) Really, if I do it every couple weeks or so, it isn't a big deal. I charge the inside one periodically as well, as I don't leave it plugged in. For that one though, I added a last-update time; with the e-paper display, it's not immediately obvious when it has run out of juice.


> why did you decide to purchase ready solutions instead of rolling your own using ESP32 for a fraction of the price?

I already had the sensors long before I had the SDR; they're paired with display units as well.


Many cool ones in this list! Other great ones:

  - https://birdnetpi.com — Bird call logging
  - https://flightaware.com/adsb/piaware/ — ADS-B Tracking
  - https://pi-hole.net — Network wide ad blocking
  - https://homebridge.io — HomeKit bridge for many devices/services


https://birdnetpi.com — Bird call logging

I love this idea. I've just started getting into birds, and I wish I had steady enough hands to build a solar+battery version of this I could stash in the woods for a week.


I've set this up recently with a cheap(~$20) USB microphone and just have it running on the back porch and it's been such a delight. Loving it!


You might be interested in picking up an AudioMoth [0]. A bit more work as you’d have to manually push through BirdNET, but easier to deploy.

https://www.openacousticdevices.info/audiomoth


Is there anything like birdnetpi, but with an ultrasound transducer for bats? I know I have them zooming around, but rarely see them, and would love to know more what their activity is like here.

Oh, checking out the AudioMoth linked elsewhere, looks like that works for recording birds and bats. Down the rabbit hole I go.


Oh this sounds fun!


Along the lines of piaware, also checkout https://liveatc.net. If you live near an airport that's not currently served by the site you can set one up moderately easy.


No blog post or pictures but I have taped an ADXL345(accelerometer) on the back of my washing + dryer and I'm using a pi to notify me when a load is done.

Didn't have the time to put a fancy algorithm to detect movement so it's rough, but it has been working perfectly for the past 4 years with no false positive/negative.

https://github.com/jebeaudet/time-to-fold-alerter


Why not detect current in the power cable? Or tap into an indicator light or relay? Way easier.


Absolutely, however I already had the accelerometer in hand for another project.


Where can I get a Pi these days. I have a work project (low volume need about 5 Pi) where I replaced a Matrix Orbital LED display and custom membrane keypad with a Pi and touchscreen. I used my own personal Pi model B but I need a few for the company and they are out of stock everywhere. (displays are not a problem, just the Pi itself)


I need a couple for a project, and yeah... good luck.

RPI400 is available pretty much everywhere, but rpi3, 4 or zeroW like they never existed.


For anyone thinking "I'll just get a 400 and open it up and pull the Pi", the 400 motherboard isn't remotely the same form factor as the usual RPi's.


I actually bought an PRi 4 8GB 2 weeks ago at my local MicroCenter, so they're definitely making (and selling) them.

I decided to check on my phone on a whim. They showed 8 in stock. By the time I got there, 30 minutes later, they had 3 left.

That PiLocator site does show the last time they've been in stock, and from my non-scientific assessment, it looks like availability is slightly getting better.


It's difficult. You can try your luck with https://rpilocator.com/


FWIW I found better luck looking for "Starter kits" that are the board + power supply + case etc. There were a couple of sites that rpilocator checked that didn't have stock listed, but did have 8gb 4bs as part of a "Starter kit" for ~£15 more.

I assume it's some agreement not to list all the variants to try to allow hobbyists to still get some.


I bought Pi Zero 2 on aliexpress few weeks ago. Can't say whether it's genuine as it's not arrived yet. But I did not find it anywhere else.


Depends on where you live, but here in Canada, PiShop (https://pishop.ca) usually has 4B kits in stock. I haven't seen single boards being available for a long time though.


Any kits with the 7" touch screen? I need some of those anyway.


Many typical Raspberry pi IOT projects can be done with ESP32/ESP8266 based boards which are highly available and very cheap.



I'll hijack this thread to ask: What are some good Pi alternatives that don't need blobs to boot and run, and that use mainline (or more-or-less mainline) kernels?

I don't need any video output, and I'm happy to pay double. What are my options?



Those look like good sources for a variety of SBCs. Thanks! But how do I narrow the selection down to my criteria?


If you just need a tiny, fanless board that runs linux, like-new Wyse3040 can be had in any quantity you like for ~$30 - $40 (ethernet only, though). Wyse5010 is a bit bigger and more capable (and has built-in wifi) around the same price.


Where are you seeing these for those prices? ebay? It'd be interesting to see what could be done with boards like this


yes. I've picked up a few on ebay:

https://www.ebay.com/sch/i.html?_nkw=wyse+3040

Many listings will not include the power supply, but if you have a drawer full of wall warts, you can probably find something that works.


Can you explain a little more? I don't know what you mean by 'blobs to boot and run'. As far as I know, the latest Linux kernel supports the raspberry pi.


The Pi actually boots from the GPU, which runs a closed-source binary blob. The GPU then starts up the ARM cores, and that's where Linux boots.


The FSF has a page on single-board computers that might be helpful, at least to narrow down your options by discarding the worse options. https://www.fsf.org/resources/hw/single-board-computers

>Some have workarounds, but some are fatally flawed and none are fully free.



Thanks! That's exactly the kind of advice I was looking for!


I wish I could find a project that would recognise a cat by its appearance and open / close a cat flap based on that. It could also make a noise or other distraction at cats that are recognised to deter them from tampering with the cat flap. The cat flaps available on the market use a chip to identify a cat, but this is a terrible method - it doesn't work more often than it does. Many times my cat was attacked by other cats because it couldn't get in and now it is scared of cat flaps.


Use a Pi with a camera module and a passive infrared motion sensor. Take a bunch of photos of your cat and other cats, using the module and the PIR to trigger it. Manually label photos as `your cat` and `not your cat` and then use https://teachablemachine.withgoogle.com/ to retrain a model based on your cat's image. Then rig a big enough servo or stepper motor to open a cat door, and a big buzzer for other cats.


Maybe this could be a starting point: https://joakimsoderberg.github.io/catcierge/ ?


Have a look at Lobe [0]. I haven't found a use case for it personally but it looks promising. The caveat is that this would only handle cat identification, you would need to build & implement the opening mechanism.

[0] https://www.lobe.ai/


Also looking for something similar. Our cat never comes indoors and therefore has a food bowl on our porch. Several other cats eat her cat food every day and it feels like we are feeding half a dozen mouths, including birds.


Maybe things have changed, but when I was looking for doggy doors I was dismayed nobody made one that would automatically open in case of a fire.


I'm no expert, but I can imagine that automatically opening an air vent to the outdoors, when a fire is detected, isn't a great idea.


On that note, one that could open in one direction only would let the pet out, but not open inwards. To the extent that this helps though, I'd wonder more about other things that are risky, like flammable furniture foam/curtains. A room and contents fire gets out of hand faster now than they used to, because the old wood furniture and natural materials are much less immediately flammable. Either way, once the heat breaks a window, that room at least will suddenly have lots of air.

I did subscribe to a monitored alarm service specifically for the smoke detectors, on the theory that while I have little need for a burglar alarm here, I would really want the fire department sent if something started while I was out. I'm on my local department, and usually home, but the neighbours wouldn't know quickly if something happened while we're away.


What we bought has several flaps (to help with insulation) and a plastic cover we can put over it at night. The flaps would still be there; I just wanted a "cover" that would come off in an emergency.


Raspis are universally unavailable and scalped for 4-6x original cost. The projects are cool but for current seekers it's essentially vaporware.


What would make the best platform for building some kind of personal dashboard/radiator on an e-ink screen?

I guess ideally I'd spend as little time as possible on tinkering with low-level rendering code.


I bought an inky 7 colour e-ink screen for rpi [0]. Pimoroni offers a python library that can write any image (jpg, png) to the screen.

Any rpi just fits with the gpio pins like a typically HAT. I'm using an rpi zero 2 w. Setup was less than 5 minutes.

I'm now hooking up a system that will take screenshots from a home assistant dashboard and push that to the display every 5 minutes.

[0] https://shop.pimoroni.com/products/inky-impression-5-7?varia...


Inkplate, with Esphome. Expensive, but a lot of the other large-ish epaper all in one boards are not the best quality or have bad library support. LilyGo makes some nice boards too but I (and others) have had variable quality for the display itself and software support is kinda eh, though there is an Esphome component in the works that is basically complete but not yet merged. Shopping for epaper boards is a pain because there are a lot of different driver ICs with varying degrees of support/open source code; even the same model of board might use the different and incompatible drivers. Inkplate basically just works and have good QC because the displays are harvested from recycled Kindles.

https://e-radionica.com/en/catalogsearch/result/?q=inkplate

https://esphome.io/components/display/inkplate6.html


Does anyone know of groovebox / OP-1 or MPC-like projects you can do with a raspi? That seems like a very fun application.


with the explosion in popularity of the pi in both home and commercial use I wonder if it makes sense for the pi foundation to shift more towards the compute module style and let the market handle the io/specialization aspect? id assume the CM4 would be less constrained by shortages since theres a simpler BOM?




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