In the ebike world, there are two paths. The first is a homemade kit bike with motors and controllers from China. The second is a prebuilt bike from a manufacturer like Giant, with motors and controllers from China, which will be half as fast and cost three times as much. The choice is obvious, and there are other benefits to taking the first path as well, such as using this equipment which now has an open source firmware option.
The Tong Sheng TSDZ2 drive is popular in the ebike world because it’s an affordable kit motor which has a pedal-assist mode using torque sensors, resulting in a more polished experience. In contrast, other popular kit motors tend to rely on less expensive cadence sensors which are not as smooth or intuitive. This new open source firmware for the TSDZ2 further improves on the ride by improving the motor responsiveness, improving battery efficiency, and opening up the ability to use any of a number of color displays. (More information is available on a separate Wiki.)
If you have a TSDZ2-based ebike it might be time to break out the laptop and get to work installing this firmware. If you’re behind the times and still haven’t figured out that ebikes are one of the best ways to travel, here is the proof you need.
Thanks to [coaxial] for the tip! Photo via Reddit user [PippyLongSausage].
Dovetails are a wedge-shaped joint found in woodworking. The wedge makes for strong joinery because a force that tries to pull it apart also increases the friction on the joint. This mallet has dovetails on either side that keep the head from flying off, but there’s also a through tenon in the center. This is an impossible joint as there’s no way to slide the mallet head onto the handle. The two pieces of wood must have grown that way!
The trick comes in the form of internal voids hidden from view once the two pieces of the mallet have been assembled. The through tenon is exactly as you’d expect: a straight tenon slides into a straight mortise in the mallet. The dovetails to either side of the handle and the pockets they mate with in the mallet head are not at all what you’d expect. The edges of the dovetail have been chamfered at 45 degrees so you can’t pull them to the outside of the mallet as you slide them into place. The opposite is the actual trick. Each of the dovetails bends inward until a ramp at the very end of the mallet pocket pushes it back into place.
Underside of mallet head shows “ramp” detail
Tenons clamped during assembly
The impossible mallet isn’t a new concept and stands as a formidable challenge for any accomplished woodworker. The images above are of [Jim Guilford’s] impossible mallet. Here the trick is fully exposed, showing the dovetail tenons of the handle clamped together as it is driven into place. Two things are striking here; the joints cannot be tested and must be perfect before assembly, and there is a real chance the tenons will break or the mallet head will split apart from the force of assembly. This project will test your courage as much as it will your patience.
The benefit of living in the modern era is that there are plenty of affordable machine tools on the market for the budding maker. However, to meet lower price points, products often forgo some of the nice-to-have features that make working easier. Of course, if you’ve got the skills to do it yourself, this needn’t be a problem, as [Zach] demonstrates.
[Zach] enjoyed using his wood lathe, but it didn’t come with a digital readout. Thankfully, retrofitting one was an easy, straightforward project. After a little research, a Hall effect sensor was chosen to detect the rotational speed of the lathe. The spindle was thus fitted with several magnets to trigger the sensor, allowing for higher resolution than just using a single device. An Arduino Nano was then used to monitor the output of the Hall effect sensor, displaying the rotational speed on a set of 7-segment displays. The project was then given its own custom PCB, and a nice 3D printed enclosure to fit it to the body of the lathe.
It’s a project that shows how easy it is to add functionality to basic machine tools using maker components. It also serves to demonstrate the value in giving a project a proper enclosure, to enable it to survive in a workshop environment. We’ve seen other hacky DRO mods before, too. Video after the break.
We use a microcontroller without a second thought, in applications where once we might have resorted to a brace of 74 logic chips. But how many of us have spared a thought for how the microcontroller evolved? It’s time to go back a few decades to look at the first commercially available microcontroller, the Texas Instruments TMS1000.
Imagine A World Without Microcontrollers
The Texas Instruments Speak & Spell from 1978 was a typical use for the TMS1000. FozzTexx (CC-SA 4.0)
It’s fair to say that without microcontrollers, many of the projects we feature on Hackaday would never be made. Those of us who remember the days before widely available and easy-to-program microcontrollers will tell you that computer control of a small hardware project was certainly possible, but instead of dropping in a single chip it would have involved constructing an entire computer system. I remember Z80 systems on stripboard, with the Z80 itself alongside an EPROM, RAM chips, 74-series decoder logic, and peripheral chips such as the 6402 UART or the 8255 I/O port. Flashing an LED or keeping an eye on a microswitch or two became a major undertaking in both construction and cost, so we’d only go to those lengths if the application really demanded it. This changed for me in the early 1990s when the first affordable microcontrollers with on-board EEPROM came to market, but by then these chips had already been with us for a couple of decades.
It seems strange to modern ears, but for an engineer around 1970 a desktop calculator was a more exciting prospect than a desktop computer. Yet many of the first microcomputers were designed with calculators in mind, as was for example the Intel 4004. Calculator manufacturers each drove advances in processor silicon, and at Texas Instruments this led to the first all-in-one single-chip microcontrollers being developed in 1971 as pre-programmed CPUs designed to provide a calculator on a chip. It would take a few more years until 1974 before they produced the TMS1000, a single-chip microcontroller intended for general purpose use, and the first such part to go on sale. Continue reading “The TMS1000: The First Commercially Available Microcontroller”→
Have you heard the exciting news about Betelgeuse? It’s been hard to miss these days, with reports of the red supergiant star suddenly dimming, and speculation growing that the star will go supernova sometime in the next 10,000 years. But the exciting part is that astronomers have gotten together and scheduled the Betelgeuse supernova for February 21, 2020. Or at least that’s how at least a half-dozen poorly written articles make it sound. We thought that seemed odd, so we dug a bit and the real story is more complicated and more interesting. Betelgeuse is normally a variable star that goes through complex cycles of brightening and dimming. Its current dimming is unprecedented in magnitude, but the timing coincides with its normal cycle. If this dimming is just a deepening of its normal cycle, the star should start brightening again on February 21. If it doesn’t, it could mean the star is entering the next phase in its evolution. We’d love to see a star so bright it’s visible in daylight and casts shadows at night, but we’ll just have to see what happens on Friday.
One of the last two factories in the world that makes the lacquer master discs needed to make vinyl records burned to the ground last week. Luckily nobody was hurt, but it took 82 firefighters hours to get the blaze under control. It remains to be seen how this loss will impact the vinyl record market, but since the appearance of a new star in the sky has long been seen as a bad omen and a portent of doom, if Betelgeuse does go boom next week, expect to hear the hipsters gnash their teeth and rend their man-buns. In the meantime, enjoy perhaps your last look at the fascinating vinyl manufacturing process.
Rent it once, rent it for life? Apparently, at least if you rent a Ford vehicle from Enterprise and install the FordPass app on your phone. That was the experience of one Masamba Sinclair when he rented a Ford Expedition in October and found that even five months later, the app – which he never unpaired from the rental vehicle – allowed him to start and stop the car’s engine, unlock the doors, and even track its location. The same thing even happened again this month when he rented a Mustang. Ford and Enterprise might both want to rethink the security model here; leaving it up to the customer to unlink the car from the app is a recipe for disaster.
Don’t forget that we have a really interesting contest going on right now: the Train All The Things machine learning contest. With so many different machine learning platforms and frameworks available today, you can surely find a way to build something that really shines. The early entries are interesting, with everything from an intelligent bat detector to sunglasses that give you control of the world. The contest is sponsored by Digi-Key and runs through April 7, so get started on your AI masterpiece and send it in.
Speaking of Digi-Key, they’ve put together a handy list of vendors from their line card who are reporting impacts from the Covid-19 outbreak in China. We wondered about supply chain effects from the outbreak recently, and this is confirmation that we’re starting to see a pinch. As of this writing, there are 62 vendors listed, with the majority reporting impacts from the extension of the Chinese New Year holiday. We’ll stay on top of this story, and of course we continue to wish our friends in China well.
When it comes to nuclear fusion, the most well-known reactor type today is no doubt the tokamak, due to its relatively straight-forward concept of plasma containment. That’s not to say that there aren’t other ways to accomplish nuclear fusion in a way that could conceivably be used in a commercial power plant in the near future.
As we covered previously, another fairly well-known type of fusion reactor is the stellarator, which much like the tokamak, has been around since the 1950s. There are other reactor types from that era, like the Z-pinch, but they seem to have all fallen into obscurity. That is not to say that research on Z-pinch reactors has ceased, or that other reactor concepts — some involving massive lasers — haven’t been investigated or even built since then.
In this article we’ll take a look at a range of nuclear fusion reactor types that definitely deserve a bit more time in the limelight.
It’s the end of another decade, and while we don’t have real hoverboards, flying cars, or affordable dental care, we do have multicolored lightbulbs you can control over WiFi. [Don Howdeshell] picked up a couple of cheap Merkury branded units in a Black Friday sale, and quickly set about hacking them.
By and large, many of these bulbs are manufactured by various companies and rebranded for whoever happens to place an order. The bulbs tend to use the Tuya IOT ecosystem. Based on the ESP8266, reflashing the bulbs with custom firmware is simple, thanks to the Tuya Convert project. Using a Linux computer with a WiFi card running in Access Point mode, it spoofs a server that tricks the Tuya product into downloading a firmware update. From there, the bulb is an open book, ready to do your bidding.
One of [Don]’s attempts didn’t go so swimmingly, however. Flashing the firmware failed and the bulb was non-functional. [Don] elected to to a teardown, photographing it for our perusal, before hooking up to the ESP8266 directly over its serial interface. From there, it was simple to reprogram the bulb with Tasmota firmware, getting it back up and running.
