Transportation Hacks

1603 Articles

Styrofoam watercraft, PCB hydrofoil

A PCB Can Be A Hydrofoil, If It Really Wants To

November 23, 2025 by 8 Comments

You know those old cliche that the younger generations have begun to cynically despise: “follow your dreams!” “You can be anything you put your mind to!” — well, perhaps they are true on occasion. For instance when [rctestflight] had PCBs that dreamed of becoming a hydrofoil, he found a way to make that dream come true.

It’s kind of obvious in retrospect: printed circuit boards are made of FR4, which is a form of fiberglass, and you know what else is commonly made of fiberglass? Boats. So yes, the material is suited for this task. The fact that solder joints hold up to use in a little remote-control hydrofoil is less obvious, but good to know. It certainly makes for easier assembly for those of us who have developed an allergy to epoxy.

Ease of assembly wasn’t really the point here: the point was that by making the “mast” of the hydrofoil out of PCB– that’s the part that holds the underwater wing– [rctestflight] figured he could (shock!) print a circuit onto it. Specifically, a liquid-level sensor, and because microcontrollers are so cheap these days he went the “total overkill” route of embedding an ESP32 on each mast. He started with a resistive sensor, but since those self-corrode too quickly, the team switched to a capacitive sensor that doesn’t need to form a galvanic cell in salt water. Come to think of it, that might still be a problem with the solder joint between the PCBs. Good thing nobody will be riding this one.

Having such a sensor and brain close-coupled allows for a faster control loop than the sonar [rctestflight] had previously been using to control his hydrofoil’s altitude.. Pivoting each mast with its own servo made for a smooth flight over the water— well, once they got the PID tuning set, anyway. Check it out in the video embedded below.

We’ve seen PCB used for enclosures before, and even the chassis of a rover, but using it for a hydrofoil is a new hack. Continue reading “A PCB Can Be A Hydrofoil, If It Really Wants To” →

Saving A Rental Ebike From The Landfill

November 23, 2025 by 14 Comments

One of the hardest things about owning a classic car is finding replacement parts. Especially if the car is particularly old or rare, or if the parent company is now out of business, sometimes this can be literally impossible and a new part will have to be manufactured from scratch. The same is true of bicycles as well, and there are plenty of defunct bicycle manufacturers to choose from. [Berm Peak] found a couple old rental ebikes from a company that’s not in business anymore and set about trying to get them working again. (Video, embedded below.)

Of course, unlike many classic cars, ebikes are encumbered by proprietary electronics and software that are much harder to replace than most physical components. As a result, these bikes get most of their electronics pulled out and directly replaced. This bike also had a seized motor, so [Berm Peak] replaced it with another hub motor he had in his shop. Some of the other highlights in the build include a custom 3D-printed latching mechanism for the battery’s attachment point at the frame, a 3D printed bezel for the new display and control unit, and the reuse of some of the other fun parts of the bike like the front basket and integrated headlight.

There are a few reasons for putting so much work into a bike like this. For this specific bike at least, the underlying components are worth saving; the sturdy metal frame and belt drivetrain are robust and won’t need much maintenance in the long term. It also only cost around $500 in parts to build a bike that would take around $2,000 to purchase new, so there’s some economic incentive as well. And in general it’s more fun and better for the world to fix things like this up and get them running again rather than buying something new off the shelf. And while proprietary electronics like those found on this bike are ubiquitous in the ebike world, they’re not all completely closed-source.

Continue reading “Saving A Rental Ebike From The Landfill” →

Handling Human Waste In The Sky

November 21, 2025 by 24 Comments

Have you ever wondered what goes into making it possible to use the restroom at 30,000 feet (10,000 m)? [Jason Torchinsky] at the Autopian recently gave us an interesting look at the history of the loftiest of loos.

The first airline toilets were little more than buckets behind a curtain, but eventually the joys of indoor plumbing took to the skies. Several interim solutions like relief tubes that sent waste out into the wild blue yonder or simple chemical toilets that held waste like a flying porta-potty predated actual flush toilets, however. Then, in the 1980s, commercial aircraft started getting vacuum-driven toilets that reduce the amount of water needed, and thus the weight of the system.

These vacuum-assisted aircraft toilets have PTFE-lined bowls that are rinsed with blue cleaning fluid that helps everything flow down the drain when you flush. The waste and fluid goes into a central waste tank that is emptied into a “honey truck” while at the airport. While “blue ice” falling from the sky happens on occasion, it is rare that the waste tanks leak and drop frozen excrement from the sky, which is a lot better than when the lavatory was a funnel and tube.

The longest ever flight used a much simpler toilet, and given the aerospace industry’s love of 3D printing, maybe a 3D printed toilet is what’s coming to an airplane lavatory near you?

A baby blue hatchback with red accents drives down a road with blurry trees and a blue sky in the background.

Hyundai Paywalls Brake Pad Changes

November 15, 2025 by 93 Comments

Changing the pads on your car’s brakes is a pretty straightforward and inexpensive process on most vehicles. However, many modern vehicles having electronic parking brakes giving manufacturers a new avenue to paywall simple DIY repairs.

Most EVs will rarely, if ever, need to replace their mechanical brake pads as in most driving situations the car will be predominantly relying on regenerative braking to slow down. A hot hatch like the Ioniq 5N, however, might go through brakes a lot faster if it spends a lot of time at the track, which is what happened with Reddit user [SoultronicPear].

Much to their chagrin, despite buying the required $60/wk subscription to the National Automotive Service Task Force (NASTF) and the $2,000 interface tool, [SoultronicPear]’s account was suspended because it was not intended for use for anyone but “service professionals.” Not exactly a Right-to-Repair friendly move on Hyundai’s part. After trying a number of different third party tools, they finally found a Harbor Freight T7 bidirectional scan tool was able to issue the parking brake retract command to perform the pad swap, albeit not without throwing some error codes in the process.

Electrification of vehicles should simplify repairs, but manufacturers are using it to do the opposite. Perhaps they should read our Minimal Motoring Manifesto? There is a glimmer of hope in the promises of Slate and Telo, but we’ll have to see if they make it to production first.

BART Display

Real-Time BART In A Box Smaller Than Your Coffee Mug

November 11, 2025 by 27 Comments

Ever get to the train station on time, find your platform, and then stare at the board showing your train is 20 minutes late? Bay Area Rapid Transit (BART) may run like clockwork most days, but a heads-up before you leave the house is always nice. That’s exactly what [filbot] built: a real-time arrival display that looks like it was stolen from the platform itself.

The mini replica nails the official vibe — distinctive red text glowing inside a sheet-metal-style enclosure. The case is 3D printed, painted, and dressed up with tiny stickers to match the real deal. For that signature red glow, [filbot] chose a 20×4 character OLED. Since the display wants 5 V logic, a tiny level-shifter sits alongside an ESP32-C6 that runs the show. A lightweight middleware API [filbot] wrote simplifies grabbing just the data he needs from the official BART API and pushes it to the little screen.

We love how much effort went into shrinking a full-size transit sign into a desk-friendly package that only shows the info you actually care about. If you’re looking for more of an overview, we’re quite fond of PCB metro maps as well.

The Cardboard Airplane Saga Continues

November 9, 2025 by 24 Comments

History is full of engineers making (or attempting to make) things out of the wrong stuff, from massive wooden aircraft to boats made of ice and sawdust. [PeterSripol] is attempting to make an ultralight aircraft out of a rather wrong material: cardboard. In the previous installment of the project, a pair of wings was fabricated. In this installment, the wings find their home on an equally mostly cardboard fuselage, complete with rudder and elevator. 

The fuselage construction amounts to little more than a cardboard box in the shape of an RC airplane. Doublers provide additional strength in critical areas, and fillets provide a modicum of additional strength around seams. To support the weight of the pilot, a piece of corrugated cardboard is corrugated again, with an additional piece making up the floor. With the addition of a couple of side windows for comfort and visibility, the fuselage is completed, but additional components need to be added.

Continue reading “The Cardboard Airplane Saga Continues” →

What Has 5,000 Batteries And Floats?

November 8, 2025 by 72 Comments

While it sounds like the start of a joke, Australian shipmaker Incat Tasmania isn’t kidding around about electric ships. Hull 096 has started charging, although it has only 85% of the over 5,000 lithium-ion batteries it will have when complete. The ship has a 40 megawatt-hour storage system with 12 banks of batteries, each consisting of 418 modules for a total of 5,016 cells. [Vannessa Bates Ramierz] breaks it down in a recent post over on IEEE Spectrum. You can get an eyeful of the beast in the official launch video, below. The Incat Tasmania channel also has other videos about the ship.

The batteries use no racks to save weight. Good thing since they already weigh in at 250 tonnes. Of course, cooling is a problem, too. Each module has a fan, and special techniques prevent one hot cell from spreading. Charging in Australia comes from a grid running 100% renewable energy. When the ship enters service as a ferry between Argentina and Uruguay, a 40-minute charge will be different. Currently, Uruguay has about 92% of its power from renewable sources. Argentina still uses mostly natural gas, but 42% of its electricity is sourced from renewable generation.

The ship is 130 meters (426 feet) long, mostly aluminum, and has a reported capacity of 2,100 people and 225 vehicles per trip. Ferry service is perfect for electric ships — the distance is short, and it’s easy to schedule time to charge. Like all electric vehicles, though, the batteries won’t stay at full capacity for long. Typical ship design calls for a 20-year service life, and it’s not uncommon for a vessel to remain in service for 30 or even 40 years. But experts expect the batteries on the ferry will need to be replaced every 5 to 10 years.

While electric ferries may become common, we don’t expect to see electric cargo ships plying the ocean soon. Diesel is hard to beat for compact storage and high energy density. There are a few examples of cargo ships using electric, though. Of course, that doesn’t mean you can’t build your own electric watercraft.

Continue reading “What Has 5,000 Batteries And Floats?” →