Machine Vision Automates Trainspotting With Unique Full-Length Portraits

As hobbies go, trainspotting is just as valid a choice as any — we don’t judge. But it does present certain logistical challenges, such as having to be in visual range of a train to be able to spot it. There’s also the fact that trains are very large objects, and they tend to move very fast. What’s a railfan to do?

If you’re also technically minded, you might try building an automatic trainspotting bot like [jo-m] has. It looks like the hardware end of “Trainbot” is pretty simple since it has been tested on both x86 and Raspberry Pi, and supports both video4linux and Pi cam. The magic is in the software, which is able to detect a train entering the frame, record images, and then stitch them together into one long image. The whole thing is coded in Go and has some interesting bits, like a custom image patch mapping package.

Trainbot gives an unusual view of a train, one that most of us accustomed to watching a train pass at a crossing have never seen. By stitching small chunks of the train as it passes, Trainbot is able to show the entire train in a single image, which would be impossible to do except for being very, very far away from the track. [jo-m] also built a web interface for Trainbot where you can check out the comings and goings yourself. Each passing train’s image is accompanied by data like its velocity and acceleration, length of the train, and time of passage. There’s also a GIF of the original source video, which is pretty cool.

Here in the States, we don’t have a lot of passenger trains to spot, but we do have some really long freight trains. It’d be interesting to see how this works with a train that’s over a mile long; that would be quite an image. Looks like someone at least has the hardware in place to give it a try.

Fail Of The Week: Car Starter Motors Aren’t The Best Fit For EBikes

A lot of what real engineering is all about is designing to the limits of your materials, with a healthy margin for error. On the other hand, seat-of-the-pants engineering often takes the opposite tack — working with the materials you have and finding their limits after the fact. While the former is more rigorous and better suited to anything where life and limb are on the line, there’s something to be said for the flexibility that informal engineering offers.

[Austin Blake]’s latest eBike is a case study in informal engineering. [Austin] started out wondering if a starter motor from a car engine would make a decent electric bike motor. Our first instinct before watching the video below was to answer that question with a resounding “No!” Yes, starter motors seem like a natural for the job, delivering high torque in a compact package. But starting a car engine is the very definition of a low-duty-cycle application, since it should only take a second or two of cranking to get an engine started. Pressing a motor designed for such a task into continuous duty seems like, well, a non-starter.

And to be fair, [Austin] fully acknowledges this from the start. He even retrofits the motor, wisely replacing the shaft bushings with proper bearings in an attempt to get a better duty cycle. And it works, at least for a while — with the motor, a homebrew battery, and an ESC mounted to a bike frame, the bike was actually pretty peppy. But bearings aren’t the only thing limiting a starter motor to intermittent duty operation. The short drive really heated up the motor, and even with a few ventilation holes knocked in the motor housing, it eventually released the Magic Smoke. The video has all the gory details.

As always, we like to stress that “Fail of the Week” is not necessarily a badge of shame. We appreciate it whenever someone shows us the way not to go, as [Austin] did here. And let’s keep in mind that he’s had success with this approach before, albeit with a much, much bigger starter motor.

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It’s Opposite Day For This Novel Wankel Engine

The Wankel engine seems to pop up in surprising places every so often, only to disappear into the ether before someone ultimately resurrects it for a new application and swears to get it right this time. Ultimately they come across the same problems that other Wankels suffered from, namely poor fuel efficiency and issues with reliability. They do have a surprising power-to-weight ratio and a low parts count, though, which is why people keep returning to this well, although this time it seems like most of the problems might have been solved simply by turning the entire design inside out.

A traditional Wankel engine has a triangular-shaped rotor that rotates around a central shaft inside an oval-shaped housing. This creates three chambers which continually revolve around inside the engine as the rotor spins. The seals that separate the chambers are notoriously difficult to lubricate and maintain. Instead of using a rotor inside of a chamber, this design called the X-Engine essentially uses a chamber inside of a rotor, meaning that the combustion chamber and the seals stay in fixed locations instead of spinning around. This allows for much better lubrication of the engine and also much higher efficiency. By flipping the design on its head it is able to maintain a low moving parts count, high compression ratio, and small power-to-weight ratio all while improving reliability and performance and adding the ability to directly inject fuel rather than rely on carburetion or other less-ideal methods of fuel delivery that other Wankels require.

Astute internal combustion aficionados will note that this engine is still of a two-stroke design, and thus not likely to fully eliminate the emissions problems with Wankels in a way that is satisfactory to regulators of passenger vehicles. Instead, the company is focusing on military, commercial, and aerospace applications where weight is a key driver of design. We’ve seen time and time again how the Wankel fails to live up to its promises though, and we hope that finally someone has cracked the code on one that solves its key issues.

Electric Volkswagen Adds Rooftop Solar

Volkswagen has continually teased the release of a new Microbus in the same way that Duke Nukem Forever strung us all along in the 00s, but unlike the fated video game it seems as though Volkswagen is finally building a hip new van rather than continually teasing its release year after year. With the clunky name of I.D. Buzz, European drivers can expect to see them later this year while those in the North American market will have to wait until 2024. That release will have a camper-equipped option though, but you may also want to equip yours with some solar panels as well.

The German tuning shop ABT is behind this design, which adds 600 watts of solar fixed to the top of the van. The solar roof will generate electricity largely to power the van’s auxiliary systems and is being aimed at those who are looking to outfit this van as a camper and need something to power things like refrigerators, interior lighting, and various electronics while on extended stays. There is also some mention of a 1000 watt option but with the limited space available on the roof may involve a side panel of some sort.

ABT is also noting that this system can be used to extend the driving range and, while technically true, don’t expect to be driving an I.D. Buzz on entirely solar power unless you’re willing to let it sit to charge the battery for days at a time. Like other solar installations on vehicles we’ve seen from various ingenious builders, the lack of real estate available on passenger vehicles limits their use largely to auxiliary electrical loads, but it can be possible to drive a vehicle on solar energy alone with the right design.

Square-Wheeled Bike Is Actually An Amazing Tracked Build

The invention of the wheel is considered one of the crowning achievements of early humanity. Squares don’t roll, after all. [The Q] decided to build a square-wheeled bike anyway, with a neat tracked setup that makes for an awesome visual gag.

The wheels are made out of C-angle steel, making them both stout and incredibly heavy. While they don’t really need the additional structure for strength, they feature spokes which mount a central hub for attaching the “wheels” to a bicycle axle. The squares aren’t designed to roll, though. Instead, they are fitted with gears and rollers, upon which a track made of bicycle chain and tires is fitted. When the rider pedals, this turns the track, propelling the bike along. Cleverly, the track mechanism is neatly hidden by some framing, confusing passers-by.

The riding experience is noisy, thanks to the tracks. There’s also plenty of rolling resistance. It’s unlikely bikes like these will become mainstream transport anytime soon, nor will you see them at the velodrome. Regardless, it’s certainly a great way to turn heads at the park.

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Riding The Rails By Ebike

As most developed countries around the world continue to modernize their transportation infrastructure with passenger rail, countries in North America have been abandoning railroads for over a century now, assuming that just one more lane will finally solve their traffic problems. Essentially the only upside to the abandonment of railroads has been that it’s possible to build some unique vehicles to explore these tracks and the beautiful yet desolate areas they reach, and [Cam Engineering] is using an ebike to do that along the coast of central California.

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A Xiaomi 3 Lite dashboard with the panel taken off and the PCB visible, four wires connected to the SWD header.

Xiaomi Scooter Firmware Hacking Gets Hands-On

Scooter hacking is wonderful – you get to create a better scooter from a pre-made scooter platform, and sometimes you can do that purely through firmware modifications. Typically, hackers have been uploading firmware using Bluetooth OTA methods, and at some point, we’ve seen the always-popular Xiaomi scooters starting to get locked down. Today, we see [Daljeet Nandha] from [RoboCoffee] continue the research of the new Xiaomi scooter realities, where he finds that SWD flashing is way more of a viable avenue that we might’ve expected. Continue reading “Xiaomi Scooter Firmware Hacking Gets Hands-On”