Hearing Plants Giggle Is Just As Creepy As You Think

While best known for Charlie and the Chocolate Factory, Roald Dahl wrote quite a few similarly oddball stories in his time. One of them, The Sound Machine, is about a device that allowed the user to hear the anguished screams of trees as they were cut down. Sounds kind of weird to us, but [Roni Bandini] liked the idea so much he decided to build his own version.

Now to be fair, the device doesn’t only scream in pain. In fact, most of the time it should be emitting laughs and happy noises. Using a moisture sensor driven into the soil of a plant’s pot, the device uses these audio cues to tell you the relative health of your leafy friend. So assuming you’ve got any sort of green thumb at all, things should be fine.

But once the soil gets too dry and the device determines the plant is in “pain”, things take a turn for the worse. We suppose it doesn’t technically scream out so much as grunt like a zombie, but it’s still not a noise we’d want to hear while walking through the house at night. Luckily, it seems you need to hit the button on the front of the 3D printed enclosure to get it to play the appropriate sound track from its DFPlayer module.

Personally we’d rather build something that makes sure the plants are being taken care of automatically than a gadget that cries out in anguish to remind us that we don’t know what we’re doing. But hey, everyone gets inspired in their own way.

Continue reading “Hearing Plants Giggle Is Just As Creepy As You Think”

Open-Source ARM Development Simplified

The ARM series of processors are an industry standard of sorts for a vast array of applications. Virtually anything requiring good power or heat management, or any embedded system which needs more computing power than an 8-bit microcontroller is a place where an ARM is likely found. While they do appear in various personal computers and laptops, [Pieter] felt that their documentation for embedded processors wasn’t quite as straightforward as it could be and created this development board which will hopefully help newbies to ARM learn the environment more easily.

Called the PX-HER0, it’s an ARM development board with an STM32 at its core and a small screen built in. The real work went in to the documentation for this board, though. Since it’s supposed to be a way to become more proficient in the platform, [Pieter] has gone to great lengths to make sure that all the hardware, software, and documentation are easily accessible. It also comes with the Command Line Interpreter (CLI) App which allows a user to operate the device in a Unix-like environment. The Arduino IDE is also available for use with some PX-HER0-specific examples.

[Pieter] has been around before, too. The CLI is based on work he did previously which gave an Arduino a Unix-like shell as well. Moving that to the STM32 is a useful tool to have for this board, and as a bonus everything is open source and available on his site including the hardware schematics and code.

A Smart Controller For Your DIY UV Cure Box

Resin 3D printers are finally cheap enough that peons like us can finally buy them without skipping too many meals, and what means we’re starting to see more and more of them in the hands of hackers. But to get good results you’ll also want a machine to cure the prints with UV light; an added expense compared to more traditional FDM printers. Of course you could always build one yourself to try and save some money.

An earlier prototype build of the interface.

To that end, [sjm4306] is working on a very impressive controller for all your homebrew UV curing needs. The device is designed to work with cheap UV strip lights that can easily be sourced online, and all you need to bring to the table is a suitable enclosure to install them in. Here he’s using a metal paint can with a lid to keep from burning his eyes out, but we imagine the good readers of Hackaday could come up with something slightly more substantial while still taking the necessary precautions to not cook the only set of eyes you’ll ever have.

Of course, the enclosure isn’t what this project is really about. The focus here is on a general purpose controller, and it looks like [sjm4306] has really gone the extra mile with this one. Using a common OLED display module, the controller provides a very concise and professional graphical user interface for setting parameters such as light intensity and cure time. While the part is cooking, there’s even a nice little progress bar which makes it easy to see how much time is left even if you’re across the room.

At this point we’ve seen a number of hacked together UV cure boxes, but many of them skip the controller and just run the lights full time. That’s fine for a quick and dirty build, but we think a controller like this one could help turn a simple hack into a proper tool.

Continue reading “A Smart Controller For Your DIY UV Cure Box”

A Super-Brain For An E-bike

There’s no better way of improving a project than logging data to make informed decisions on future improvements. When it came to [Brian]’s latest project, an electric bike, he wanted to get as much data as he could from the time he turned it on until the time he was finished riding. He turned to a custom pyBoard-based device (and wrote it up on Hackaday.io), but made it stackable in order to get as much information from his bike as possible.

This isn’t so much an ebike project as it is about a microcontroller platform that can be used as a general purpose device. All of the bike’s controls flow through this device as a logic layer, so everything that can possibly be logged is logged, including the status of the motor and battery at any given moment. This could be used for virtually any project, and the modular nature means that you could scale it up or down based on your specific needs. The device is based on an ARM microcontroller so it has plenty of power, too.

While the microcontroller part is exceptionally useful ([Brian] talks about some of its other uses here and gives us even more data on his personal webpage), we shouldn’t miss the incredible bike that [Brian] built either. It has a 3 kW rear hub motor and can reach speeds of around 60 mph. While we let the commenters below hash out the classic argument of “bicycle vs. motorcyle” we’ll be checking out some electric vehicles that are neither.

ESP8266 Adds Web Control To Old Home Theater

There was a time when you could hold onto a TV or A/V receiver for the better part of the decade and not feel as though you were missing out on the latest and greatest features. But today you’re lucky to get three years out of a “smart” TV before it’s either supplanted by a vastly improved version, or falls victim to some weird issue that (surprise, surprise) means you need to buy a new one.

A simple touch interface hosted on the ESP8266

Not content with the status quo of planned obsolescence, [aamarioneta] recently set out to add a sprinkling of modern convenience to a circa 2008 Denon AVR 2308 home theater receiver. Like any good A/V receiver, the AVR 2308 features a dizzying array of ports on the back panel, one of which happens to be for an external infrared receiver. This turned out to be the perfect place to jack in an ESP8266, earning this 12 year old receiver an honorary membership into the Internet of Things.

The interesting thing about this hack is that there’s actually no IR involved. Sure, the code could be used to drive an IR LED attached to the ESP8266’s GPIO pins, and the AVR 2308 would respond as if the original remote was being used; but where’s the fun in that? Thanks to the receiver port, they’re able to inject the IR codes directly into the device. It’s the same protocol, just without the photons.

With a simple web-interface running on the ESP8266, they can control the AVR 2308 from a smartphone’s browser anywhere in the house. From here it would only take a few more lines of code to tie it into an existing home automation system or add in support for Alexa voice control.

We love seeing projects that add modern features to older hardware, as that’s one less piece of gear sent to an early grave because its owner felt they were behind the curve. It’s getting a bit unfriendly out there for consumers, and anything that puts the power back into the owner’s hands is a step in the right direction.

Scott Shawcroft Is Programming Game Boys With CircuitPython

Some people like to do things the hard way. Maybe they drive a manual transmission, or they bust out the wire wrap tool instead of a soldering iron, or they code in assembly to stay close to the machine. Doing things the hard way certainly has its merits, and we are not here to argue about that. Scott Shawcroft — project lead for CircuitPython — on the other hand, makes a great case for doing things the easy way in his talk at the 2019 Hackaday Superconference.

In fact, he proved how easy it is right off the bat. There he stood at the podium, presenting in front of a room full of people, poised at an unfamiliar laptop with only the stock text editor. Yet with a single keystroke and a file save operation, Scott was able make the LEDs on his Adafruit Edge Badge — one of the other pieces of hackable hardware in the Supercon swag bag — go from off to battery-draining bright.

Code + Community

As Scott explains, CircuitPython prides itself on being equal parts code and community. In other words, it’s friendly and inviting all the way around. Developing in CircuitPython is easy because the entire environment — the code, toolchain, and the devices — are all extremely portable. Interacting with sensors and other doodads is easy because of the import and library mechanics Python is known for, both of which are growing within the CircuitPython ecosystem all the time.

CircuitPython is so friendly that it can even talk to old hardware relatively easily without devolving into a generational battle. To demonstrate this point, Scott whipped out an original Nintendo Game Boy and a custom cartridge, which he can use to play fun sounds via the Game Boy’s CPU.

Now You’re Playing With Python

It’s interesting to see the platforms on which Scott has used the power of CircuitPython. The Game Boy brings the hardware for sound and pixel generation along with some logic, but he says it’s the code on the cartridge that does the interesting stuff.

The CPU communicates with carts at a rate of 1MHz. As long as you can keep this rate up and the CPU understands your instructions, you can get it to do anything you want.

Scott’s custom cart has a 120MHz SAMD51. He spends a second explaining how he gets from Python libraries down to the wire that goes to the Game Boy’s brain — basically, the C code underneath CircuitPython accesses direct structs defined within the SAMD to do Direct Memory Access (DMA), which allows for jitter-free communication at 1MHz.

He’s using the chip’s lookup tables to generate a 1MHz signal out of clock, read, and A15 in order to send music-playing instructions to the sound register of the Game Boy’s CPU. It sounds like a lot of work, but CircuitPython helps to smooth over the dirty details, leaving behind a simpler interface.

If you want easy access to hardware no matter how new or nostalgic, the message is clear: snake your way in there with CircuitPython.

Continue reading “Scott Shawcroft Is Programming Game Boys With CircuitPython”

ESP32 Rover With PCB Chassis Is Ready To Roll

The microcontrollers are cheap, the sensors are cheap, even the motors are cheap. So why are all the good wheeled robotics platforms so expensive? [Dimitris Platis] wanted to develop an affordable platform for experimenting with rovers, but the cheap plastic chassis he was using gave him all sorts of problems. So he did what any good hacker would do, and built a better version himself.

Interestingly, [Dimitris] decided to go with a chassis made from two PCB panels. The motors, mounted to small angled brackets, bolt directly to the lower PCB. These aren’t your standard $2 DC cans either. Each JGB37-520 gearhead motor comes complete with an encoder that allows your software to determine speed, distance, and direction. The upper PCB connects to the lower with several rows of pin headers, and plays host to whatever electronics payload you might be experimenting with at the time.

For the controller, [Dimitris] says the ESP32 is hard to beat by pretty much any metric you want to use. With integrated wireless and considerable computational power, there’s plenty of options for controlling your little rover either remotely or autonomously. But he also says that every effort has been made to ensure that you could switch out the microcontroller with something else should you want to spin up a customized version.

The whole idea reminds us a bit of quadcopters we’ve seen in the past, where the PCB wasn’t just being used structurally as a place to bolt the motors and hardware to, but actually contained functional traces and components that reduced how much wiring you needed to do. Naturally, this means that any damage to the chassis might cripple the electronics, but presumably, that’s what the big foam bumpers are there for.

[Dimitris] designed this project for educational use, so he assumes you’ll want to build 10 or 12 of these for your whole classroom. In those quantities, he says each bot will cost around $60. If you wanted to reduce the price a bit more, he says swapping the motors would be your best bet as they’re the single most expensive component of the design. That said, $60 for a quality open source rover platform sounds pretty fair to us.

Still too much? You could check out one of the 3D printable rover designs we’ve covered over the years. Or see if you can get lucky and pick up a cheap robot from the clearance rack and hack it.