Transportation Hacks

1507 Articles

A vaguely boat-shaped vehicle with three wheels and a mast. It sits in a barren-looking plain with short mountains in the distance

Sailing The High Steppes

October 10, 2024 by 27 Comments

Sails typically bring to mind the high seas, but wind power has been used to move craft on land as well. Honoring this rich tradition, [Falcon Riley] and [Amber Word] decided to sail across Mongolia in a sailing cart.

Built in a mere three days from $200 in materials they were able to scrounge up the week before, the cart served as their home for the 300 km (~186 mi) journey across the Mongolian countryside. Unsurprisingly, bodging together a sailing vessel in three days led to some mechanical failures along the way, mostly due to gopher holes, but friendly locals lent a hand to get them back on the road.

Built mostly out of plywood, the fully-laden cart tipped the scales at 225 kg (500 lbs) and didn’t roll well enough to tow by hand. Under sail, however, they managed to cover the distance in 46 days, including 70 km in one particularly windy day. Not the fastest way to travel by any means, but not bad given the quick build time. We suspect that a more lightweight and aerodynamic build could yield some impressive results. Maybe it’s time for a new class at Bonneville?

If you want to learn to sail in your own landlocked region, maybe learn a bit first? Instead you might want to build an autonomous sailing cart or take a gander at sailing out of this world?

3D Printed Bearings With Filament Rollers

October 9, 2024 by 24 Comments

Commodity bearings are a a boon for makers who to want something to rotate smoothly, but what if you don’t have one in a pinch? [Cliff] of might have the answer for you, in the form of 3D printed bearings with filament rollers.

With the exception of the raw filament rollers, the inner and outer race, roller cage and cap are all printed. It would also be possible to design some of the components right into a rotating assembly. [Cliff] makes it clear this experiment isn’t about replacing metal bearings — far from it. Instead, it’s an inquiry into how self-sufficient one can be with a FDM 3D printer. That didn’t stop him from torture testing the design to its limits as wheel bearings on an off-road go-cart. The first version wasn’t well supported against axial loads, and ripped apart during some more enthusiastic maneuvers.

[Cliff] improved it with a updated inner race and some 3D printed washers, which held up to 30 minutes of riding with only minimal signs of wear. He also made a slightly more practical 10 mm OD version that fits over an M3 bolt, and all the design files are downloadable for free. Cutting the many pieces of filament to length quickly turned into a chore, so a simple cutting jig is also included.

Let us know in the comments below where you think these would be practical. We’ve covered some other 3D printed bearing that use printed races, as well as a slew bearing that’s completely printed. Continue reading “3D Printed Bearings With Filament Rollers” →

Soaring At Scale: Modular Airship Design

October 8, 2024 by 32 Comments

If you’re looking for an intriguing aerial project, [DilshoD] has you covered with his unique twist on modular airships. The project, which you can explore in detail here, revolves around a modular airship composed of individual spherical bodies filled with helium or hydrogen—or even a vacuum—arranged in a 3x3x6 grid. The result? A potentially more efficient airship design that could pave the way for lighter-than-air exploration and transport.

The innovative setup features flexible connecting tubes linking each sphere to a central gondola, ensuring stable expansion without compromising the airship’s integrity. What’s particularly interesting is [DilshoD]’s use of hybrid spheres: a vacuum shell surrounded by a gas-filled shell. This dual-shell approach adds buoyancy while reducing overall weight, possibly making the craft more maneuverable than traditional airships. By leveraging materials like latex used in radiosonde balloons, this design also promises accessibility for makers, hackers, and tinkerers.

Though this concept was originally submitted as a patent in Uzbekistan, it was unfortunately rejected. Nevertheless, [DilshoD] is keen to see the design find new life in the hands of Hackaday readers. Imagine the possibilities with a modular airship that can be tailored for specific applications. Interested in airships or modular designs? Check out some past Hackaday articles on DIY airships like this one, and dive into [DilshoD]’s full project here to see how you might bring this concept to the skies.

Vehicle-To-Everything: The Looming Smart Traffic Experience

October 7, 2024 by 47 Comments

Much of a car’s interaction with the world around it is still a very stand-alone, analog experience, regardless of whether said car has a human driver or a self-driving computer system. Mark I eyeballs or equivalent computer-connected sensors perceive the world, including road markings, traffic signs and the locations of other road traffic. This information is processed and the car’s speed and trajectory are adjusted to ideally follow the traffic rules and avoid unpleasant conversations with police officers, insurance companies, and/or worse.

An idea that has been kicked around for a few years now has been to use wireless communication between cars and their environment to present this information more directly, including road and traffic conditions, independent from signs placed near or on the road. It would also enable vehicle-to-vehicle communication (V2V), which somewhat like the transponders in airplanes would give cars and other vehicles awareness of where other traffic is hanging out. Other than V2V, Vehicle-to-Everything (V2X) would also include communication regarding infrastructure (V2I), pedestrians (V2P) and an expansive vehicle-to-network (V2N) that gives off strong Ghost in the Shell vibes.

Is this is the future of road traffic? The US Department of Transport (DOT) seems to think that its deployment will be a good thing, but V2X has been stuck in regulatory hurdles. This may now change, with the DOT releasing a roadmap for its deployment.

Continue reading “Vehicle-To-Everything: The Looming Smart Traffic Experience” →

3D Printed Hydrofoil Goes From Model Scale To Human Scale With Flight Controller

October 6, 2024 by 5 Comments

Hydrofoils have been around for several decades, but watching a craft slice through the water with almost no wake never get old. In the videos after the break, [rctestflight] showcases his ambitious project: transforming a standup paddleboard into a rideable hydrofoil with active stabilization.

Unlike conventional electric hydrofoil boards that depend on rider skill for balance, [rctestflight] aims to create a self-stabilizing system. He began by designing a small-scale model, complete with servo-controlled ailerons and elevators, dual motors for differential thrust, and a dRehmFlight flight controller. A pair of sonar sensors help the flight controller maintain constant height above the water. The wings are completely 3D printed, with integrated hinges for flight control surfaces slots for wiring and control components. It’s better suited for 3D printing than RC aircraft since it’s significantly less sensitive to weight, allowing for more structural reinforcement. The small scale tests were very successful and allowed [rctestflight] to determine that he didn’t need the vertical stabilizer and rudder.

The full-sized version features a scaled up wing, larger servos and motors attached to an 11-foot standup paddleboard — minus its rear end — mounted on commercially available e-foil booms. A foam battery box stores a hefty LiFePO4 battery, while the electronics from the smaller version are repurposed here. Despite only catching glimpses of this larger setup in action at the end of the video, it promises an excitingly smooth lake ride we would certainly like to experience.

We’ve seen several 3D printed hydrofoils around here, but this promised to be the largest successful attempt. Don’t fail us [Daniel].

Continue reading “3D Printed Hydrofoil Goes From Model Scale To Human Scale With Flight Controller” →

Why Electric Trains Sound The Way They Do

October 5, 2024 by 20 Comments

If you’re a seasoned international rail traveler you will no doubt have become used to the various sounds of electric locomotives and multiple units as they start up. If you know anything about electronics you’ll probably have made the connection between the sounds and their associated motor control schemes, but unless you’re a railway engineer the chances are you’ll still be in the dark about just what’s going on. To throw light on the matter, [Z&F Railways] have a video explaining the various control schemes and the technologies behind them.

It’s made in Scotland, so the featured trains are largely British or in particular Scottish ones, but since the same systems can be found internationally it’s the sounds which matter rather than the trains themselves. Particularly interesting is the explanation of PWM versus pattern mode, the latter being a series of symmetrical pulses at different frequencies to create the same effect as PWM, but without relying on a single switching frequency as PWM does. This allows the controller to more efficiently match its drive to the AC frequency demanded by the motor at a particular speed, and is responsible for the “gear change” sound of many electric trains. We’re particularly taken by the sound of some German and Austrian locomotives (made by our corporate overlords Siemens, by coincidence) that step through the patterns in a musical scale.

Not for the first time we’re left wondering why electric vehicle manufacturers have considered fake internal combustion noises to make their cars sound sporty, when the sound of true electrical power is right there. The video is below the break.

Continue reading “Why Electric Trains Sound The Way They Do” →

Xiaomi M365 Battery Fault? Just Remove A Capacitor

October 1, 2024 by 11 Comments

Electric scooters have long been a hacker’s friend, Xiaomi ones in particular – starting with M365, the Xiaomi scooter family has expanded a fair bit. They do have a weak spot, like many other devices – the battery, something you expect to wear out.

Let’s say, one day the scooter’s diagnostics app shows one section of the battery going way below 3 volts. Was it a sudden failure of one of the cells that brought the whole stage down? Or perhaps, water damage after a hastily assembled scooter? Now, what if you measure the stages with a multimeter and it turns out they are perfectly fine?

Turns out, it might just be a single capacitor’s fault. In a YouTube video, [darieee] tells us all about debugging a Xiaomi M365 battery with such a fault – a BQ76930 controller being responsible for measuring battery voltages. The BMS (Battery Management System) board has capacitors in parallel with the cells, and it appears that some of these capacitors can go faulty.

Are you experiencing this particular fault? It’s easy to check – measure the battery stages and see if the information checks out with the readings in your scooter monitoring app of choice. Could this be a mechanical failure mode for this poor MLCC? Or maybe, a bad batch of capacitors? One thing is clear, this case is worth learning from, adding this kind of failure to your collection of fun LiIon pack tidbits. This pack seems pretty hacker-friendly – other packs lock up when anything is amiss, like the Ryobi batteries do, overdue for someone to really spill their secrets!

Continue reading “Xiaomi M365 Battery Fault? Just Remove A Capacitor” →