The Next Best Thing To A Cybertruck

May 21, 2020 by Bryan Cockfield 14 Comments

While production of the Tesla Cybertruck won’t start production until 2021 (at the earliest), you can always try to build your own. Unless you have a really big spare parts drawer, though, it probably won’t be full sized, but you can at least build a model if you have a shop as well-stocked as [Emiel]. He took some time to build a model cybertruck out of a single sheet of aluminum. (Video, embedded below. You might want to turn on subtitles.)

This project is a great example of the fact that some projects that seem simple on the surface require some specialized tools to get just right. To start, the aluminum sheet was cut with a laser to get into the appropriate shape and include details like windows, and the bending points were marked with an engraver to help the bending process along. The one tool that [Emiel] was missing was a brake, but he got great results with a set of metal bending pliers.

Finishing the model didn’t go particularly smoothly, either. He had planned to braze the metal together, but the heat required kept warping the body panels. The solution was to epoxy it together and sand down the excess, and the results are hopefully stronger than brazing would have been since he added a cloth to the epoxy for extra strength. The windows are made from polycarbonate (and didn’t break during the durability test), and we hope that when [Emiel] is ready to put in a motor he uses one of his custom-built electric motors. Continue reading “The Next Best Thing To A Cybertruck” →

Electric Vehicles Continue The Same Wasteful Mistakes That Limit Longevity

May 15, 2020 by Jenny List 372 Comments

A while back, I sat in the newish electric car that was the pride and joy of a friend of mine, and had what was at the time an odd experience. Instead of getting in, turning the key, and driving off, the car instead had to boot up.

The feeling was of a piece of software rather than a piece of hardware, and there was a tangible wait before the start button could be pressed. It was a miracle of technology that could travel smoothly and quietly for all but the longest journeys I could possibly throw at it on relative pennies-worth of electricity, but I hated it. As a technologist and car enthusiast, I should be all over these types of motor vehicles. I live for new technology and I lust after its latest incarnations in many fields including automobiles.

I want my next car to have an electric motor, I want it to push the boundaries of what is capable with a battery and I want it to be an automotive tour de force. The switch to electric cars represents an opportunity like no other to deliver a new type of car that doesn’t carry the baggage of what has gone before, but in that car I saw a future in which they were going badly astray.

I don’t want my next vehicle to be a car like my friend’s one, and to understand why that is the case it’s worth going back a few decades to the cars my parents drove back when when jumpers were goalposts, and the home computer was just a gleam in the eye of a few long-haired outsiders in California.

Continue reading “Electric Vehicles Continue The Same Wasteful Mistakes That Limit Longevity” →

Foamboard Makes For A Light Hovercraft

May 12, 2020 by Al Williams 3 Comments

If we are to believe many science fiction movies, one day throngs of people wearing skin-tight silver spandex jumpsuits will be riding around on hovercraft. Hovercraft haven’t really taken the world by storm, but [Fitim-Halimi] built his own model version and shows you how he did it. You can see the little craft moving in the video below.

In theory, a hovercraft is pretty simple, but in practice they are not as easy as they look. For one thing, you need a lot of air to fill the plenum chamber to get lift. That’s usually a noisy operation. The solution? In this case, a hairdryer gave up its motor for the cause. In addition, once floating on a near-frictionless cushion of air, you have to actually move without contacting the ground. Like many real hovercraft, this design uses another fan to push it along. You can see in the video that the designer uses Jedi hand motions to control the vehicle.

Continue reading “Foamboard Makes For A Light Hovercraft” →

NASA Readies New Electric X-Plane For First Flight

April 28, 2020 by Tom Nardi 78 Comments

Since 1951, NASA (known in those pre-space days as NACA) and the United States Air Force have used the “X” designation for experimental aircraft that push technological boundaries. The best known of these vehicles, such as the X-1 and X-15, were used to study flight at extreme altitude and speed. Several fighter jets got their start as X-planes over the decades, and a number of hypersonic scramjet vehicles have flown under the banner. As such, the X-planes are often thought of as the epitome of speed and maneuverability.

So the X-57 Maxwell, NASA’s first piloted X-plane in two decades, might seem like something of a departure from the blistering performance of its predecessors. It’s not going to fly very fast, it won’t be making any high-G turns, and it certainly won’t be clawing its way through the upper atmosphere. The crew’s flight gear won’t even be anything more exotic than a polo and a pair of shorts. As far as cutting-edge experimental aircraft go, the X-57 is about as laid back as it gets.

But like previous X-planes, the Maxwell will one day be looked back on as a technological milestone of its own. Just as the X-1 helped usher in the era of supersonic flight, the X-57 has been developed so engineers can better understand the unique challenges of piloted electric aircraft. Before they can operate in the public airspace, the performance characteristics and limitations of electric planes must be explored in real-world scenarios. The experiments performed with the X-57 will help guide certification programs and government rule making that needs to be in place before such aircraft can operate on a large scale.

Continue reading “NASA Readies New Electric X-Plane For First Flight” →

Right To Repair: Tractor Manufacturers Might Have Met Their Match In Australia

April 21, 2020 by Jenny List 60 Comments

The simmering duel between farmers and agricultural machinery manufacturers over access to the software to unlock the DRM which excludes all but the manufacturer’s agents from performing repairs goes on. How this plays out will have implications for the right to repair for everyone on many more devices than simply tractors. Events so far have centred on the American Midwest, but there is an interesting new front opening up in Australia. The Aussie government consumer watchdog, the ACCC, is looking into the matter, and examining whether the tractor manufacturers are in breach of the country’s Competition and Consumer Act. As ABC News reports there is a dual focus, both of the DRM aspect and on the manufacturer’s harvesting and lock-in of customer farm data.

This is an exciting turn of events for anyone with an interest in the right to repair, because it takes the manufacturers out of the comfort zone of their home legal environment into one that may be less accommodating to their needs. If Aussie farmers force them to open up their platforms then it will benefit all of us, but even if it fails, the fact that the issue has received more publicity in a different part of the world can only be a good thing. There are still tractor manufacturers that do not load their machines with DRM, how long will it be we ask before the easy repairability of their products becomes a selling point?

There are many stories relating to this issue on these pages, our most recent followed the skirmishes in Nebraska.

Thanks Stuart Longland for the tip.

Header image, John Deere under Australian skies: Bahnfrend (CC BY-SA 4.0).

Huge 3D-Printed LEGO Go Kart Makes You The Minifig

April 19, 2020 by Mike Szczys 7 Comments

The LEGO Technic line is definitely the hacker’s flavor of LEGO. It brings a treasure trove of engineering uses that make axles, gears, pulleys, and motors a thing. The only problem is that it’s the inanimate minifigures having all of the fun. But not if [Matt Denton] has something to say about it. He’s building a huge 3D-printed go-kart with pieces scaled up 8.43 times the size of their LEGO equivalents. That’s large enough for an adult to fit!

You may remember seeing [Matt’s] previous attempt at something like this about three years back, but that was only around half the size of this one. He printed a blue kart for his nephew, but it didn’t quite scale up enough even for a child to ride. This one is impressively large, but that raises some interesting fabrication issues

The long beams that make up the frame of the vehicle and the axle piece (the black rods with an X-shaped profile) used for the steering column are far too long to print in one go. So the axle was printed in two parts with a square channel down the center that hides a single run of square tubing. But the beams are much more interesting. Printed in two parts, there’s a dovetail-shaped connector piece that holds the top joint together, and a hidden bolt for the bottom. Glue is also used along the joint to bolster the holding power of the mechanical fasteners.

In general, the weight and friction on this scaled up version need many considerations. [Matt] explains where he’s made design decisions — like perpendicular axle connectors that have proper bearings — to include mostly-hidden metal parts and fasteners to ensure the plastic doesn’t fail. The thing looks awesome, but just wait until you see the assembly process. It’s sooooo satisfying to watch the modular parts snap into place. The project’s still in progress and before he’s done he plans to add an electric motor to make the kart go.

Even if you’re not scaling a model up to full size, giant is a guaranteed recipe for fun. Case in point, [Matt’s] enlarged LEGO fork lift is a delight.

Continue reading “Huge 3D-Printed LEGO Go Kart Makes You The Minifig” →

A Broken Inductor As A Bike Chain Sensor

April 19, 2020 by Jenny List 31 Comments

If you have ever broken the ferrite core of an inductor, you’ll probably sympathize with [Oliver Mattos]. He accidentally stood on a ferrite-cored component, breaking it and rendering it useless. But utility is in the eye of the beholder, and instead of throwing it away he’s repurposed it as a chain sensor for his electric bicycle.

The broken inductor was positioned on the rear frame of the machine such that the chain passed through the area where the broken half of its core would once have been. As each link passes through the magnetic field it causes the inductance to change, and from this the speed, direction, and tension of the chain can be read.

Adding a 180 nF capacitor in parallel with the inductor creates a tuned circuit, and measuring the inductance is as straightforward as firing a single pulse at it and measuring the time it takes to go negative. Chain speed can be read by sensing the change in inductance as each link passes, tension by sensing the change in inductance as the chain is closer or further away, and direction by whether the chain is slack or not. It’s an ingenious and simple solution to measuring a bicycle chain, and we like it.

A lot of bicycle measurement systems have passed our way over the years, but it’s fair to say they have been more concerned with displays than sensors.