Author: Bryan Cockfield

1852 Articles

Making Models With Lasers

November 16, 2019 by 4 Comments

Good design starts with a good idea, and being able to flesh that idea out with a model. In the electronics world, we would build a model on a breadboard before soldering everything together. In much the same way that the industrial designer [Eric Strebel] makes models of his creations before creating the final version. In his latest video, he demonstrates the use of a CO2 laser for model making.

While this video could be considered a primer for using a laser cutter, watching some of the fine detail work that [Eric] employs is interesting in the way that watching any master craftsman is. He builds several cubes out of various materials, demonstrating the operation of the laser cutter and showing how best to assemble the “models”. [Eric] starts with acrylic before moving to wood, cardboard, and finally his preferred material: foam core. The final model has beveled edges and an interior cylinder, demonstrating many “tricks of the trade” of model building.

Of course, you may wish to build models of more complex objects than cubes. If you have never had the opportunity to use a laser cutter, you will quickly realize how much simpler the design process is with high-quality tools like this one. It doesn’t hurt to have [Eric]’s experience and mastery of industrial design to help out, either.

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A Self-Expanding PWM Driver

November 15, 2019 by 8 Comments

For smaller microcontrollers, having enough outputs for the job is sometimes a challenge. A common solution is to do some sort of multiplexing with the available outputs or perhaps something more advanced such as Charlieplexing, but another good option is to use a specialized driver board. What’s even better is if you can daisy chain driver boards to get even more outputs.

[Eric] has been working on a 16 channel LED project but first wanted to build a driver board with 8 channels. Before building a full 16 channel version he realized that he could take the same 8 channel board, make a mirror image of it, and attach it underneath the first board with headers in order to double the number of channels available. Without having to build a separate 16-channel board, this shortcut saved [Eric] some time and a great deal of effort.

This is a great example of working smarter, not harder. Each of the 8 or 16 channels has full PWM support as well to support PWM dimming, and a similar board could be built for motor control as well. It’s a good illustration of how good design can end up working for you as well. And if you need even more outputs, Charlieplexing is one way to get them.

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Two Vintage Calculators In One

November 13, 2019 by 10 Comments

The FPGA revolution that occurred within the past few decades was a boon to many people interested in “antique” electronics. The devices “wire together” logic elements as needed rather than emulating chips completely in a software layer, which makes them uniquely suited for replicating chips that are rare, no longer in production, damaged, or otherwise lost. They also make it easy to experiment with hardware, like this project which combines two antique calculators into one single unit.

The two calculators used in this combination device are the TI Datamath and the Sinclair Scientific, both released in the early 1970s, the former of which has been extensively documented and reverse engineered on at least one occasion. The reproduction from [zpekic] has a toggle that allows the user to switch between the two “modes”. This showcases the power of microprogramming and microcode, and of the FPGA platform itself. Although both modes are functional, there are still a few bugs resulting from how different the two pieces of hardware were, which is really more of an interesting facet of this project than anything.

The build is a great showcase of FPGA technology, not to mention a great read-through for understanding these two calculators and their fundamental differences in data entry and manipulation, clock cycles, memory, and everything in between. It’s worth checking out, even if you don’t plan on using a decades-old calculator in your day-to-day life.

Bicycle Transforms Mid-Ride

November 13, 2019 by 9 Comments

For those of us who were children in the late 80s and early 90s, we may have dreamed of one day owning a gigantic tractor trailer that could transform into a colossal fighting robot. Or of simply having a toy that could approximate this change from one form into another. As adults, though, we have come to realize that this is wishful thinking. That is, unless we decide to build this transforming bicycle.

What starts out as a slightly unusual-looking low rider-style bike effortlessly turns into a tall bike by means of a gas cylinder fixed to the bike’s rear triangle. The bike started out as a full suspension mountain bike, but the rear spring was removed to make room for this cylinder. The pivoting action of the rear triangle in a mountain bike is the key design element here: it allows the frame to change shape easily, in this situation when pushed by the cylinder. Adding some longer forks in the front and a coat of paint finishes the build.

This bike was entered in the Make It Move contest on Instrucables, and has gotten some pretty wide recognition so far. It’s a unique bicycle to be sure, and we’ve seen a few. From Russian offroad electric utility bicycles to bicycles that keep drivers from speeding down roads, there have been lots of interesting bike-based builds.

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3D Print Your Very Own Mechanical Computer

November 10, 2019 by 30 Comments

Most Hackaday readers are familiar with computers from the 70s and 80s, but what about ones even older than that? The Digi Comp 1 was a commercially available computer from the 1960s that actually cost less than a modern-day microcontroller. The catch? It was mechanical rather than electrical. Thanks to retro-wizard [Mike Gardi], now anyone can build a replica of one.

Admittedly the Digi Comp 1 was more of a toy than a tool, but it was still a working computer. It contained three flip-flops (memory) and had a lever that acted as a clock, allowing the user to perform boolean operations and some addition and subtraction. Certainly not advanced, but interesting nonetheless. [Mike]’s version of the Digi Comp 1 has an extra bit when compared to the original and includes some other upgrades, but largely remains faithful to the original design.

If you want to print one of these on your own, [Mike] has made all of the files available on Thingiverse. He has also experimented with other mechanical computers as well, including the sequel Digi Comp 2. We’ve seen some recent interest in that mechanical computer lately as well.

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Weather Station Gets Much-Needed Upgrades

November 9, 2019 by 8 Comments

Weather stations are a popular project, partly because it’s helpful (and interesting) to know about the weather at your exact location rather than a forecast that might be vaguely in your zip code. They’re also popular because they’re a good way to get experience with microcontrollers, sensors, I/O, and communications protocols. Your own build may also be easily upgradeable as the years go by, and [Tysonpower] shows us some of the upgrades he’s made to the popular Sparkfun weather station from a few years ago.

The Sparkfun station is a good basis for a build though, it just needs some updates. The first was that the sensor package isn’t readily available though, but some hunting on Aliexpress netted a similar set of sensors from China. A Wemos D1 Mini was used as a replacement controller, and with it all buttoned up and programmed it turns out to be slightly cheaper (and more up-to-date) than the original Sparkfun station.

All of the parts and code for this new station are available on [Tysonpower]’s Github page, and if you want to take a look at a similar station that we’ve featured here before, there’s one from three years ago that’s also solar-powered.

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Hiring From A Makerspace Pays Off

November 7, 2019 by 12 Comments

A makerspace is a great place to use specialty tools that may be too expensive or large to own by oneself, but there are other perks that come with participation in that particular community. For example, all of the skills you’ve gained by using all that fancy equipment may make you employable in some very niche situations. [lukeiamyourfather] from the Dallas Makerspace recently found himself in just that situation, and was asked to image a two-million-year-old fossil.

The fossil was being placed into a CT machine for imaging, but was too thick to properly view. These things tend to be fragile, so he spent some time laser cutting an acrylic stand in order to image the fossil vertically instead of horizontally. Everything that wasn’t fossil had to be non-conductive for the CT machine, so lots of fishing line and foam was used as well. After the imaging was done, he was also asked to 3D print a model for a display in the museum.

This is all going on at the Perot Museum of Nature and Science if you happen to be in the Dallas area. It’s interesting to see these skills put to use out in the wild as well, especially for something as rare and fragile as studying an old fossil. Also, if you’d like to see if your local makerspace measures up to the Dallas makerspace, we featured a tour of it back in 2014, although they have probably made some updates since then.