Home Safety Monitoring With IoT

Home automation is a popular project to undertake but its complexity can quickly become daunting, especially if you go further than controlling a few lights (or if you’re a renter). To test the waters you may want to start with something like this home safety monitor, which is an IoT device based on an Arduino. It allows remote monitoring of a home for things such as temperature, toxic gasses, light, and other variables, which is valuable even if you don’t need or want to control anything.

The device is built around an Arduino Nano 33 IOT which has WiFi and Bluetooth capabilities as well as some integrated security features. This build features a number of sensors including pressure/humidity, a gas/smoke detector, and a light sensor. To report all of the information it gathers around the home, an interface with Ubidots is configured to allow easy (and secure) access to the data gathered by the device.

The PCB and code for the project are all provided on the project page, and there are a number of other options available if Ubidots isn’t your preferred method of interfacing with the Internet of Things. You might even give Mozilla’s WebThings a shot if you’re so inclined.

Exploring Early ’90s Video Game Architecture With Another World

Curious about past computer architectures? Software engineer [Fabien Sanglard] has been experimenting with porting Another World, an action-adventure platformer, to different machines and comparing the results in his “Polygons of Another World” project.

The results are pretty interesting. Due to the game’s polygon-based graphics, optimizations vary widely across different architectures, with tricks allowing the software to run on hardware released five years before the game’s publication. The consoles explored are primarily from the early ’90s, ranging from the Amiga 500, Atari ST, IBM PC, and Super Nintendo to the Sega Genesis.

The actual game contains very little code, with the original version at 6000 lines of assembly and the PC DOS executable only containing 20 KiB. The executable simply exists as a virtual machine host that reads and executes uint8_t opcodes, with most of the business logic implemented with bytecode. The graphics use 16 palette-based colors, despite the Amiga 500 supporting up to 32 colors. However, the aesthetics still fit the game nicely, with some very pleasant pixel art.

There’s a plethora of cool tricks that emerge in each of the ports, starting with the original Amiga 500 execution. Prior to the existence of the CPU/GPU architecture, microprocessors had blitters – logic blocks that rapidly modified data within the memory, capable of copying large swathes of data in parallel with the CPU, freeing up the CPU for other operations.

To display the visuals, a framebuffer containing a bitmap drives the display. There are three framebuffers used, two for double buffering and one for saving the background composition to avoid redrawing static polygons. Within the framebuffer, several tricks are used to improve the graphical experience. For scenes with translucent hues, special values are interpreted from the framebuffer index by “reading the framebuffer index, adding 0x8 and writing back”.

Challenges also come when manipulating pixels given each machine’s CPU and bus bandwidth limitations. For filling in bits, the blitter uses a feature called “Area Fill Mode” that scans left to right to find edges, rendering the bit arrays with spaces between lines filled in. Since the framebuffer is stored in five separate areas of memory – or bitplanes – this requires drawing the lines and filling in areas four times, multiplying by the hundreds of polygons rendered by the engine. The solution was to set up a temporary “scratchpad” buffer and rendering a polygon into the clean space. The polygon can then get copied to the screen area with a masked blit operation since the blitter can render anywhere in memory.

Intrigued? The series continues with deep dives into Atari ST, IBM PC, and upcoming writeups on SEGA Genesis/MegaDrive.

Get Compressed Air From Falling Water With The Trompe

If you’re like us, understanding the processes and methods of the early Industrial Revolution involved some hand waving. Take the blast furnace, which relies on a steady supply of compressed air to stoke the fire and supply the oxygen needed to smelt iron from ore. How exactly was air compressed before electricity? We assumed it would have been from a set of bellows powered by a water wheel, and of course that method was used, but it turns out there’s another way to get compressed air from water: the trompe.

As [Grady] from Practical Engineering explains in the short video below, the trompe was a clever device used to create a steady supply of high-pressure compressed air. To demonstrate the process, he breaks out his seemingly inexhaustible supply of clear acrylic piping to build a small trompe. The idea is to use water falling around a series of tubes to create a partial vacuum and entrain air bubbles. The bubbles are pulled down a vertical tube by the turbulence of the water, and then enter a horizontal section where the flow evens out. The bubbles rise to the top of the horizontal tube where they are tapped off by another vertical tube, as the degassed water continues into a second vertical section, the height of which determines the pressure of the stored air. It’s ingenious, requiring no power and no moving parts, and scales up well – [Grady] relates a story about one trompe that provided compressed air commercially for mines in Canada.

Need an electricity-free way to pump water instead of air? Check out this hydraulic ram pump that takes its power from the water it pumps.

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A Simple Auger Pet Feeder

Pet feeders are a popular maker project. One can speculate that this shows the great self-confidence common to the maker set, who are willing to trust their own work to keep their animal companions alive for many days at a a time. [Darren Tarbard] is one such maker, who put together this simple auger build.

The project consists of a hopper for dry pet food, into which a screw auger is inserted. Both parts are 3D printed, making them easy to produce at home for the average maker. The build was designed specifically around the parts [Darren] had to hand, namely a 28BYJ-48 stepper motor, which is charged with turning the auger. Running the show is an Arduino, which can be run with whatever suitable timing code is necessary to feed the particular pet in question. There’s also a remixed version that adds a larger food storage dish on top for longer periods of unattended operation, created by [szuchid].

It’s a basic build, but one that would be readily achievable by most makers with little more than some junkbox components and a roll of filament. Of course, if your pet prefers wet food, you might need a different design. Video after the break.

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Jen Costillo Explains Why Hackers Thrive In A Recession

If you haven’t noticed, this is an absolutely fantastic time to be a hacker. The components are cheap, the software is usually free, and there’s so much information floating around online about how to pull it all together that even beginners can produce incredible projects their first time out of the gate. It’s no exaggeration to say that we’re seeing projects today which would have been all but impossible for an individual to pull off ten years ago.

But how did we get here, and perhaps more importantly, where are we going next? While we might arguably be in the Golden Age of DIY, creative folks putting together their own hardware and software is certainly nothing new. As for looking ahead, the hacker and maker movement is showing no signs of slowing down. If anything, we’re just getting started. With a wider array of ever more powerful tools at our disposal, the future is very literally whatever we decide it is.

In her talk at the 2019 Hackaday Superconference, The Future is Us: Why the Open Source And Hobbyist Community Drive Consumer Products, Jen Costillo not only presents us with an overview of hacker history thus far, but throws out a few predictions for how the DIY movement will impact the mainstream going forward. It’s always hard to see subtle changes over time, and it’s made even more difficult by the fact that most of us have our noses to the proverbial grindstone most of the time. Her presentation is an excellent way for those of us in the hacking community to take a big step back and look at the paradigm shifts that put such incredible power in the hands of so many.

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Who Invented The Mouse? Are You Sure?

If you ask most people who invented the mouse, they won’t know. Those that do know, will say that Doug Englebart did. In 1964 he had a box with two wheels that worked like a modern mouse as part of his work at Stanford Research Institute. There is a famous demo video from 1968 of him showing off what looks a lot like an old Mcintosh computer. Turns out, two other people may have an earlier claim to a mouse — or, at least, a trackball. So why did you never hear about those?

The UK Mouse

Ralph Benjamin worked for Britain’s Royal Navy, developing radar tracking systems for warships. Right after World War II, Ralph was working on the Comprehensive Display System — a way for ships to monitor attacking aircraft on a grid. They used a “ball tracker.” Unlike Engelbart’s mouse, it used a metallic ball riding on rubber-coated wheels. This is more like a modern non-optical mouse, although the ball tracker had you slide your hand across the ball instead of the other way around. Sort of a trackball arrangement.

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Hackaday Podcast 050: Counterfeit Chips, Servo Kalimba, Resistor Colors, Pi Emulation, And SED Maze Solver

Hackaday editors Elliot Williams and Mike Szczys work their way through a dizzying maze of great hacks this week, bringing you along for the ride. We take a look at simplifying home automation with Node-RED and marvel at the misuse of the SED — Linux’s stream editor for filtering and transforming text — to find your way through a maze. Have the hippest portable; grab your really old Apple laptop and stuff a not-so-old Apple desktop inside. We bring it on home with our love (or hate?) for the resistor color code.

Take a look at the links below if you want to follow along, and as always tell us what you think about this episode in the comments!

Direct download (60 MB)

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