BikeBeamer Adds POV Display To Bicycle Wheels

June 11, 2024 by Bryan Cockfield 16 Comments

Unless you’re living in a bicycle paradise like the Netherlands, most people will choose to add some sort of illumination to their bicycle to help drivers take note that there’s something other than a car using the road. Generally, simple flashing LEDs for both the front and the rear is a pretty good start, but it doesn’t hurt to add a few more lights to the bicycle or increase their brightness. On the other hand, if you want to add some style to your bicycle lighting system then this persistence of vision (POV) display called the BikeBeamer from [locxter] might be just the thing.

The display uses four LED strips, each housed in their own 3D printed case which are installed at 90-degree angles from one another in between the spokes of a standard bicycle wheel. An ESP32 sits at the base of one of the strips and is responsible for storing the image and directing the four displays. This is a little more complex than a standard POV display as it’s also capable of keeping up with the changing rotational speeds of the bicycle wheels when in use. The design also incorporates batteries so that no wires need to route from the bike frame to the spinning wheels.

This is an ongoing project for [locxter] as well, meaning that there are some planned upgrades even to this model that should be in the pipe for the future. Improving the efficiency of the code will hopefully allow for more complex images and even animations to be displayed in the future, and there are also some plans to improve the PCB as well with all surface-mount components. There are a few other ways to upgrade your bike’s lighting as well, and we could recommend this heads-up headlight display to get started.

AI Kayak Controller Lets The Paddle Show The Way

June 10, 2024 by Dan Maloney 6 Comments

Controlling an e-bike is pretty straightforward. If you want to just let it rip, it’s a no-brainer — or rather, a one-thumber, as a thumb throttle is the way to go. Or, if you’re still looking for a bit of the experience of riding a bike, sensing when the pedals are turning and giving the rider a boost with the motor is a good option.

But what if your e-conveyance is more of the aquatic variety? That’s an interface design problem of a different color, as [Braden Sunwold] has discovered with his DIY e-kayak. We’ve detailed his work on this already, but for a short recap, his goal is to create an electric assist for his inflatable kayak, to give you a boost when you need it without taking away from the experience of kayaking. To that end, he used the motor and propeller from a hydrofoil to provide the needed thrust, while puzzling through the problem of building an unobtrusive yet flexible controller for the motor.

His answer is to mount an inertial measurement unit (IMU) in a waterproof container that can clamp to the kayak paddle. The controller is battery-powered and uses an nRF link to talk to a Raspberry Pi in the kayak’s waterproof electronics box. The sensor also has an LED ring light to provide feedback to the pilot. The controller is set up to support both a manual mode, which just turns on the motor and turns the kayak into a (low) power boat, and an automatic mode, which detects when the pilot is paddling and provides a little thrust in the desired direction of travel.

The video below shows the non-trivial amount of effort [Braden] and his project partner [Jordan] put into making the waterproof enclosure for the controller. The clamp is particularly interesting, especially since it has to keep the sensor properly oriented on the paddle. [Braden] is working on a machine-learning method to analyze paddle motions to discern what the pilot is doing and where the kayak goes. Once he has that model built, it should be time to hit the water and see what this thing can do. We’re eager to see the results.
Continue reading “AI Kayak Controller Lets The Paddle Show The Way” →

Reverse Engineering Keeps Early Ford EVs Rolling

June 7, 2024 by Dan Maloney 5 Comments

With all the EV hype in the air, you’d be forgiven for thinking electric vehicles are something new. But of course, EVs go way, way back, to the early 19th century by some reckonings. More recently but still pretty old-school were Ford’s Think line of NEVs, or neighborhood electric vehicles. These were commercially available in the early 2000s, and something like 7,200 of the slightly souped-up golf carts made it into retirement communities and gated neighborhoods.

But as Think aficionado [Hagan Walker] relates, the Achille’s heel of these quirky EVs was its instrument cluster, which had a nasty habit of going bad and taking the whole vehicle down with it, sometimes in flames. So he undertook the effort of completely reverse engineering the original cluster, with the goal of building a plug-in replacement.

The reverse engineering effort itself is pretty interesting, and worth a watch. The microcontroller seems to be the primary point of failure on the cluster, probably getting fried by some stray transients. Luckily, the microcontroller is still available, and swapping it out is pretty easy thanks to chunky early-2000s SMD components. Programming the MCU, however, is a little tricky. [Hagan] extracted the code from a working cluster and created a hex file, making it easy to flash the new MCU. He has a bunch of other videos, too, covering everything from basic diagnostics to lithium battery swaps for the original golf cart batteries that powered the vehicle.

True, there weren’t many of these EVs made, and fewer still are on the road today. But they’re not without their charm, and keeping the ones that are still around from becoming lawn ornaments — or worse — seems like a noble effort.

Continue reading “Reverse Engineering Keeps Early Ford EVs Rolling” →

Retrotechtacular: TVO

June 6, 2024 by Jenny List 18 Comments

Hardware hackers come from a variety of backgrounds, but among us there remains a significant number whose taste for making things was forged through growing up in a farm environment. If that’s you then like me it’s probable that you’ll melt a little at the sight of an older tractor, and remember pretending to drive one like it at pre-school age, and then proudly driving it for real a few years later before you were smart enough to realise you’d been given the tedious job of repeatedly traversing a field at a slow speed in the blazing sun. For me those machines were Ford Majors and 5000s, Nuffields, the ubiquitous red Fergusons, and usually relegated to yard duty by the 1970s, the small grey Ferguson TE20s that are in many ways the ancestor of all modern tractors.

The Black Art Of Mixing Your Own Fuel

There was something odd about some of those grey Fergies in the 1970s, they didn’t run on diesel like their newer bretheren, nor did they run on petrol or gasoline like the family Austin. Instead they ran on an unexpected mixture of petrol and heating oil, which as far as a youthful me could figure out, was something of a black art to get right. I’d had my first encounter with Tractor Vapour Oil, or TVO, a curious interlude in the history of agricultural engineering. It brings together an obscure product of the petrochemical industry, a moment when diesel engine technology hadn’t quite caught up with the on-farm requirement, and a governmental lust for a lower-tax tractor fuel that couldn’t be illicitly used in a car.

TVO is a fuel with a low octane rating, where the octane rating is the resistance to ignition through compression alone. In chemical terms octane rating a product of how many volatile aromatic hydrocarbons are in the fuel, and to illustrate it your petrol/gasoline has an octane rating in the high 90s, diesel fuel has one close to zero, and TVO has a figure in the 50s. In practice this was achieved at the refinery by taking paraffin, or kerosene for Americans, a heavier fraction than petrol/gasoline, and adding some of those aromatic hydrocarbons to it. The result was a fuel on which a standard car engine wouldn’t run, but which would run on a specially low-compression engine with a normal spark ignition. This made it the perfect tax exempt fuel for farmers because it could only be used in tractors equipped with these engines, and thus in the years after WW2 a significant proportion of those Fergies and other tractors were equipped to run on it. Continue reading “Retrotechtacular: TVO” →

The Dyke Delta: A DIY Flying Wing Fits Four

June 4, 2024 by Elliot Williams 24 Comments

The world of experimental self-built aircraft is full of oddities, but perhaps the most eye-catching of all is the JD-2 “Dyke Delta” designed and built by [John Dyke] in the 1960s. Built to copy some of the 1950’s era innovations in delta-style jet aircraft, the plane is essentially a flying wing that seats four.

And it’s not just all good looks: people who have flown them say they’re very gentle, they get exceptional gas mileage, and the light wing-loading means that they can land at a mellow 55 miles per hour (88 kph). And did we mention the wings fold up so you can store it in your garage?

Want to build your own? [John] still sells the plans. But don’t jump into this without testing the water first — the frame is entirely hand-welded and he estimates it takes between 4,000 and 5,000 hours to build. It’s a labor of love. Still, the design is time-tested, and over 50 of the planes have been built from the blueprints. Just be sure to adhere to the specs carefully!

It’s really fun to see how far people can push aerodynamics, and how innovative the experimental airplane scene really is. The JD-2 was (and probably still is!) certainly ahead of its time, and if we all end up in flying wings in the future, maybe this plane won’t look so oddball after all.

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This Mobile Hackerspace Can Be Yours

June 2, 2024 by Jenny List 22 Comments

Wandering round the field at EMF Camp, our eye was caught by an unusual sight, at least to European eyes. The type of campervan body which sits on the back of a pickup truck is not particularly common on this side of the Atlantic, but there one was, fitted out as a mobile makerspace. If that wasn’t enough, this one is for sale.

Here at Hackaday we’re neither estate agents or in the want-ads business, so we’re unaccustomed to property promotion. We’re still not immune to the attraction of a portable makerspace to take to events though, and this one provides a very practical basis. It started life as what Brits call a Luton van body, a box van, and inside it’s gained a small kitchen, benches and shelves either side, and up in the space over the cab, a double bed. Sadly the laser cutter and 3D printers aren’t included.

If you live in Southern England and you want to be the envy of everyone at your next hacker camp, an email to richjmaynard at gmail dot com with a sensible offer might secure it. We would be first in the queue if we had the space, because what Wrencher scribe wouldn’t want an office like this!

Quad-Motor Electric Kart Gets A Little Too Thrilling

May 21, 2024 by Donald Papp 38 Comments

[Peter Holderith] has been on a mission to unlock the full potential of a DIY quad-motor electric go-kart as a platform. This isn’t his first rodeo, either. His earlier vehicle designs were great educational fun, but were limited to about a kilowatt of power. His current platform is in theory capable of about twenty. The last big change he made was adding considerably more battery power, so that the under-used motors could stretch their legs a little, figuratively speaking.

How did that go? [Peter] puts it like this: “the result of [that] extra power, combined with other design flaws, is terror.” Don’t worry, no one’s been hurt or anything, but the kart did break in a few ways that highlighted some problems.

The keyed stainless steel bracket didn’t stay keyed for long.

One purpose of incremental prototyping is to bring problems to the surface, and it certainly did that. A number of design decisions that were fine on smaller karts showed themselves to be inadequate once the motors had more power.

For one thing, the increased torque meant the motors twisted themselves free from their mountings. The throttle revealed itself to be twitchy with a poor response, and steering didn’t feel very good. The steering got heavier as speed increased, but it also wanted to jerk all over the place. These are profoundly unwelcome feelings when driving a small and powerful vehicle that lurches into motion as soon as the accelerator is pressed.

Overall, one could say the experience populated the proverbial to-do list quite well. The earlier incarnation of [Peter]’s kart was a thrilling ride, but the challenge of maintaining adequate control over a moving platform serves as a reminder that design decisions that do the job under one circumstance might need revisiting in others.