Hackaday editors Mike Szczys and Elliot Williams marvel at a week packed full of great hardware hacks. Do you think the engineers who built the earliest home computers knew that their work would be dissected decades later for conference talks full of people hungry to learn the secret sauce? The only thing better than the actual engineering of the Commodore floppy drive is the care with which the ultimate hardware talk unpacks it all! We look upon a couple of EV hacks — one that replaces the inverter in a Leaf and the other details the design improvements to Telsa’s self-hiding door handles. Before we get to medieval surgery and USB-C power delivery, we stop for a look at a way to take snapshots of Game Boy gameplay and an electric plane engine that looks radial but is all gears.
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!
If you look around your desk right now, odds are you’ll see a 7-segment display or two showing you some vital information like the time or today’s weather. But think of how much information you could see with over 1,100 digits, like with [Chris Combs’] 7200-segment display.
For [Chris], this project started the same way that many of our projects start; finding components that were too good of a deal to pass up on. For just “a song or two plus shipping”, he was the proud owner of two boxes of 18:88 7-segment displays, 500 modules in total. Rather than sitting and using up precious shelf space, [Chris] decided to turn them into something fancy he could hang on the wall.
The IS31FL3733 can produce 8 levels of dimming 8-bit PWM, allowing [Chris] to display in grayscaleThe first challenge was trying to somehow get a signal to all of the individual segments. Solutions exist for running a handful of displays in one device, but there are certainly no off-the-shelf solutions for this many. Even the possible 16 addresses of the IS31FL3733 driver IC [Chris] chose for this project were not enough, so he had to get creative. Fearing potential capacitance issues with simply using an i2C multiplexer, he instead opted to run 3 different i2C busses off of a Raspberry Pi 4, to interface with all 48 controllers.
The second challenge was how to actually wire everything up. The finished display comes out to 26 inches across by 20.5 inches tall, much too large for a single PCB. Instead, [Chris] opted to design a series of self-contained panels, each with 6 of the display modules and an IS31FL3733 to drive them. While the multiplexing arrangement did leave space for more segments on each panel, he opted to go for this arrangement as it resulted in a nice, clean, 4:3 aspect ratio for the final display.
The end result was a unique and beautiful piece, which Chris titled “One-to-Many”. He uses it to display imagery and art related to the inevitability of automation, machines replacing humans, and other “nice heartwarming stuff like that”, as he puts it. There’a video after the break, but if you are interested in seeing the display for yourself, it will be on display at the VisArt’s Concourse Gallery in Rockville, MD from September 3 to October 17, 2021. More info on [Chris’s] website.
Imagine visiting a home that was off the grid, using hydroelectric power to run lights, a dishwasher, a vacuum cleaner, and a washing machine. There’s a system for watering the plants and an intercom between rooms. Not really a big deal, right? This is the twenty first century, after all.
Image of Armstrong and his 7-inch gun from an 1887 edition of Illustrated London News
But then imagine you’ve exited your time machine to find this house not in the present day, but in the year 1870. Suddenly things become quite a bit more impressive, and it is all thanks to a British electrical hacker named William Armstrong who built a house known as Cragside. Even if you’ve never been to Northumberland, Cragside might look familiar. It’s appeared in several TV shows, but — perhaps most notably — played the part of Lockwood Manor in the movie Jurassic World: Fallen Kingdom.
Armstrong was a lawyer by training but dabbled in science including hydraulics and electricity — a hot topic in the early 1800s. He finally abandoned his law practice to form W. G. Armstrong and Company, known for producing Armstrong guns, which were breech-loading artillery pieces ranging from 2.5 inch bores up to 7 inches. By 1859, he was knighted and became the principal supplier of armaments to both the Army and the Navy.
This series of monthly teardowns was started in early 2018 as an experiment, and since you fine folks keep reading them, I keep making them. But in truth, finding a new and interesting gadget every month can sometimes be a chore. Which is why I’m always so thankful when a reader actually sends something in that they’d like to see taken apart, as it absolves me from having to make the decision myself. Of course it also means I can’t be blamed if you don’t like it, so keep that in mind as well.
Coming our way from the tropical paradise of Eastern Pennsylvania, this month’s subject is an ADT branded Impassa SCW9057G-433 alarm system that was apparently pulled off the wall when our kind patron was moving house. As you might have guessed from the model number, this unit uses 433 MHz to communicate with various sensors and devices throughout the home, and also includes a 3G cellular connection that allows it to contact the alarm monitoring service even if the phone line has been cut.
The alarm can connect to a wide array of 433 MHz devices.
From how many of these are on eBay, and the research I’ve done on some home alarm system forums, it appears that you can actually pick one of these up on the second-hand market and spin your own whole-house alarm system without going through a monitoring company like ADT. The extensive documentation from Impassa covers how to wire and configure the device, and as long as the system isn’t locked when you get it, it seems like wiping the configuration and starting from scratch isn’t a problem.
If it’s possible to put together your own homebrew alarm system with one of these units at the core, then it seems the least we can do is take it apart and see what kind of potentially modifiable goodies are waiting under that shiny plastic exterior.
Over the years we’ve seen many takes on the 7-segment display. Among the most interesting are the mechanical versions of what is most often an LED-based item. This week’s offering is from [John Burd], who published a very odd video showing off the clock he made. But look beyond YouTuber antics and you’ll see the stepper motors he used to turn the segments are dripping with graceful beauty. (Video, embedded below.)
Okay if you want to hear [Charlie Sheen] say “Raspberry P-eye”, this is the video for you. [John] used Cameo to get the (former?) star to talk about what was used to build the clock. Like we said, the video is weird. Let’s embrace that right away and then never talk about it again.
The thing is, the build is such a good idea. [John] went with some stepper motors you can source relatively cheaply from Ali Express and the like. Typically they’re around a buck or two each and have a couple of wings for screw mounting brackets. This builds on the segment displays we’ve seen that use hobby servos by allowing you finer control of how the segments move. Sure, the 90° rotation isn’t all that much to work with, but it will be much smoother and you can get fancy with the kinematics you choose. The only place we see room for improvement is the alignment of the segments when they are turned “off” as you can see the center segment in the video thumbnail below is not quite level. Maybe a linkage mechanism would allow for a hing mechanism that aligns more accurately while hiding the servos themselves behind the mounting plate? It’s in your hands now!
In the demo video you’ll also find some interesting test rigs built to proof out the project. One just endurance tests the mechanism, but the other two envision water-actuated segments. One pumps a hollow, transparent segment with colored liquid. The other tried to use water droplets sprayed in the air to illuminate laser segments. Both are cool and we’d like to see more of the oddball approaches which remind us of the ferrofluid clock.
With some time to kill and an array of old Apple computers on hand, [Pierre Dandumont] wondered if he could continuously upgrade a single OS drive from the oldest system he had, System 7.1 on a Performa 630, to the latest version of MacOS on a MacBook Air. He recalled watching an old video which demonstrated a continuous upgrade from DOS to Windows 10 (we think this video from 2016 may be the one), which gave him the inspiration for this journey. [Pierre] documents his efforts on his blog (in French; English translated link is here).
Along the way, he installed 24 different operating systems
System 7.1.2, 7.5
Mac OS 7.6
Mac OS 8.0, 8.1, 8.5, 8.6
Mac OS 9.0, 9.1, 9.2
Mac OS X 10.0 – 10.11
macOS 10.12, 10.13
on seven Mac computers
Performa 630 (ca. 1994, Motorola 68040)
Power Mac G3 Beige (ca. 1997, Motorola PowerPC 730)
Power Mac G3 Blue (ca. 1999, Motorola PowerPC 730)
Power Mac G4 Digital Audio (ca. 2001, Motorola PowerPC 7400)
Mac mini G4 (ca. 2005, Motorola PowerPC 7447)
Mac mini 2009 (Intel Core 2 Duo Penryn)
MacBook Air 2012 (Intel Core i5/i7)
across three of the four processor families spanned by the Macintosh line of computers since their introduction in 1984. You can see in the lead photo the success, where the Mac OS 8 search tool Sherlock is shown in the dock of a MacBook Air running High Sierra.
[Francesco] developed a parametric design tool called SOL75 which aims to take the drudgery out of designing the basic mechanical parts used in projects. He knows how to design things like gears, pulleys, belts, brackets, enclosures, etc., but finds it repetitive and boring. He would rather spend his time on the interesting and challenging portions of his project instead.
The goal of SOL75 is to produce OpenSCAD and STL files of a part based on user requirements. These parameters go beyond the simple dimensional and include performance characteristics such as peak stress, rigidity, maximum temperature, etc. The program uses OpenSCAD to generate the geometries and a core module to evaluate candidate designs. In an attempt to overcome the curse of dimensionality, [Francesco] has trained an AI oracle to quickly accept or reject candidate solutions.
In the realm of parametric design aids, you have projects like NopSCADlib which dimensionally parameterize a large collection of common objects by numbers alone ( a 100 cm long, 6.35 mm diameter brass tube with 1.22 mm wall thickness ) or industry standard specifications ( a 10 mm long M3 socket head cap screw ). This approach doesn’t take into account whether the object will hold up in your application nor does it consider any 3D printing issues. At the other extreme, there are the generative design and optimization tools found in professional packages like Fusion 360 and SolidWorks which can make organic-looking items that are optimized precisely for the specified conditions.
SOL75 seems to fall in the middle, combine characteristics of both approaches. It gives you the freedom to select dimensional parameters and performance requirements, yet bounds the solution space by only offering objects that have been prepared ahead of time by domain experts — if you ask for an L-bracket, you’ll get an L-bracket and not something that looks like a spider web or frog leg.
Once you compile the design, SOL75 generates the OpenSCAD and/or STL files and a bill of materials. But wait — there’s more– it also makes a thorough design handbook documenting the part in great detail, including the various design considerations and notes on printing. Here is a demonstration link for an electronics enclosure which is pretty interesting. There is also an example of using SOL75 to make a glider, which you can read about on the Hackaday.io project page.
For now, [Francesco] has only made SOL75 available in a register-by-email online Beta version, as he’s still undecided on what form the final version will be. Do you have any success (or failure) stories regarding generative designs? Let us know in the comments below.
