Behold The Mega-Wheelie, A Huge One-Wheeled Electric Skateboard

October 29, 2023 by Donald Papp 8 Comments

DIY electric personal vehicles are a field where even hobbyists can meaningfully innovate, and that’s demonstrated by the Mega-Wheelie, a self-balancing one-wheeled skateboard constructed as an experiment in traversing off-road conditions.

[John Dingley] and [Nick Thatcher] have been building and testing self-balancing electric vehicles since 2008, with a beach being a common testing ground. They suspected that a larger wheel was the key to working better on rough ground and dry sand and tested this idea by creating a skateboard with a single wheel. A very big, very wide wheel, in fact.

The Mega-Wheelie houses a 24V LiFePO4 battery pack, 450 W gearmotor with chain and sprocket drive, SyRen motor controller from Dimension Engineering, Arduino microcontroller, and an inertial measurement unit to enable the self-balancing function. Steering is done by leaning, and the handheld controller is just a dead man’s switch that disables the vehicle if the person piloting it lets go.

Design-wise, a device like this has a few challenging constraints. A big wheel is essential for performance but takes up space that could otherwise be used for things like batteries. Also, the platform upon which the pilot stands needs to be as low to the ground as possible for maximum stability. Otherwise, it’s too easy to fall sideways. On the other hand, one must balance this against the need for sufficient ground clearance.

Beaches are rarely covered in perfectly smooth and firm sand, making them a good test area.

In the end, how well did it work? Well enough to warrant a future version, says [John]. We can’t wait to see what that looks like, considering their past 3000 W unicycle’s only limitation was “personal courage” and featured a slick mechanism that shifted the pilot’s weight subtly to aid steering. A video of the Mega-Wheelie (and a more recent unicycle design) is embedded just below the page break.

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Open Source Key Programmer For HiTag2 Keys

October 28, 2023 by Lewin Day 9 Comments

Hitag transponders have been used in a wide variety of car keys as a protective measure against hot-wiring and theft. They’re also a reason why it’s a lot more expensive to get car keys duplicated these days for many models that use this technology. However, there is now an open source programmer that works with these transponder keys, thanks to [Janne Kivijakola].

The hack uses an old reader device salvaged from a Renault in a scrapyard, hooked up to an Arduino Mega 2560 or Arduino Nano. With this setup, key transponders can be programmed via a tool called AESHitager, which runs on Windows. It’s compatible with a variety of Hitag transponders, including Hitag2, Hitag3, and Hitag AES, along with the VVDI Super Chip and certain types of BMW keys.

If you’ve been having issues with coded keys, this project might just be what you need to sort your car out. Everything you need is available on GitHub for those wishing to try this at home. We’ve seen some interesting hacks in this space before, too. Video after the break.

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Level Your Trailer Or RV With This Nifty Helper Device

October 25, 2023 by Lewin Day 30 Comments

Getting your RV or trailer parked nice and level is key to getting a good night’s sleep. Traditional methods involve bubble levels and trial and error, but [MJCulross] wanted something better. Enter the Teensy RV Leveling Helper.

The device uses an accelerometer to detect the pitch and roll angles of the RV. It then displays these on a small screen, and performs calculations on how much the RV must be raised at each corner to bring it level. The RV’s width and wheelbase can be entered via a simple touchscreen interface to ensure the calculations are correct. There’s also a trailer mode which calculates three-point leveling figures for the wheels and the hitch, as opposed to the four-wheeled RV mode.

The result is that the correct leveling blocks can be selected first time when parking up the RV or trailer. It’s a lot less tedious than the usual method of parking, leveling, checking, and then leveling again.

We don’t see a lot of camper hacks around here, but we’ve noticed a new trend towards lightweight cycle campers in recent years. If you’ve found your own nifty hacks for your home on the open road, don’t hesitate to let us know!

A Quick And Stealthy Mobile Slot Antenna From Copper Tape

October 25, 2023 by Dan Maloney 41 Comments

[Ben Eadie (VE6SFX)] is at it again with the foil tape, and this time he’s whipped up a stealthy mobile sunroof antenna for the amateur radio operator with the on-the-go lifestyle.

You may recall [Ben]’s recent duck tape antenna for the 70-cm ham band, an ultra-lightweight design that lends itself to easy packing for portable operation. The conductors in that antenna were made from copper foil tape, a material that’s perfect for all sorts of specialized applications, like the slot antenna that he builds in the video below. In the ham world, slot antennas are most frequently seen cut into the main reflector of a direct satellite dish, often in hopes of avoiding the homeowner association’s antenna police. Even in the weird world of RF, it’s a strange beast because it relies on the absence of material in a large planar (or planar-ish) conductive surface.

Rather than grabbing an angle grinder to make a slot in the roof of his car, [Ben] created a “virtual” slot with copper tape on the inside of his car’s sunroof. His design called for a 39″ (0.99-m) slot, so he laid out a U-shaped slot to fit the window and outlined it with copper foil tape. His method was a little complex; he applied the copper tape to a transparent transfer film first, then stuck the whole thing to the underside of the glass in one go. It didn’t quite go as planned, but as he learned in the duck tape antenna, the copper tape makes it easy to repair mistakes. A BNC connector with pigtails is attached across the slot about 4″ (10 cm) up from the end of one of the short legs of the slot; yes, this looks like a dead short, but such are the oddities of radio.

Is it a great antenna? By the numbers on [Ben]’s NanoVNA, not really. But any antenna that gets you heard is a good antenna, and this one was more than capable in that regard. We’ll have to keep this in mind for impromptu antennas and for those times when secrecy is a good idea.

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Flaming Skull Hood Ornament Is Not Suitable For Use In Traffic

October 24, 2023 by Lewin Day 16 Comments

It’s one thing to mount a big skull—human or animal—to the front of your car. Really, though, a good hood skull should breathe fire to truly inspire enmity or awe. Thankfully, when [Anthony] went about modifying his ex-school bus, he was sure to equip it with suitably flaming equipment. It’s dangerous, so don’t try this one at home and melt your car, you hear?

The build started with an off-the-shelf replica cow skull, in lovely flame-resistant metal. It was then plumbed with a propane feed that could be triggered by a 12-volt solenoid. This was combined with a high-voltage coil driving a grill igniter to provide the necessary initiating spark.

To go forth with flames, first, a missile switch must be flipped up and engaged to arm the system. Then, hitting the skull-and-crossbones button will send fire surging forth from the front of the vehicle.

Alternatively, a wireless keyfob can be used, which bypasses the arming system—so leaving the remote in a pocket is ill-advised.

Amazingly, a former project posted on Hackaday served as an inspiration for this build.

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Tank Boots Are A Dangerous Way To Get Around Town

October 19, 2023 by Lewin Day 12 Comments

Rollerskates are all well and good, but they’re even more fun when they’re powered. Then again, why stick with wheels, when you can have the off-road benefits of tracked propulsion? That’s precisely what [Joel] was thinking when he built this impressive set of Tank Boots.

The build uses a set of tracks from a tracked snowblower, sourced for $50. The tracks are a simple design sans suspension, consisting of a pair of plastic wheels inside the tracks and run via a chain drive. Each snowblower track was given a metal frame with a ski boot and a motor, gearbox, and controller straight out of a power drill. Power was courtesy of a lithium-polymer battery pack.

Riding the boots isn’t easy, with falls and tumbles rather common. Regardless, they get around great offroad in a way that regular rollerblades never could. Bolted together, they make a great tank chair, too. We’ve actually looked at the benefits of tracks versus wheels before, too. Video after the break.

Can A $3200 Kit Convert Your Car To Electric Power?

October 15, 2023 by Jenny List 114 Comments

Whether hardcore petrolheads like it or not, we appear to be living through the final years of the internal combustion engine. In many countries there are legislative timetables in place for their eventual phasing out, and even those which remain in production are subject to ever more stringent emissions legislation. If there’s a problem with the EVs with which we’re expected to replace our fossil fuel vehicles it’s the cost, those things are still very expensive. An Aussie student has an interesting idea that’s won the James Dyson Prize: a low cost conversion for existing vehicles that bolts onto their rear wheel hubs.

Electric conversion of fossil fuel cars is nothing new, indeed we’ve brought you news of units designed to replace the original engine and transmission. Neither are wheel hub motors new, but the difference with this system is that it doesn’t require significant mechanical modification to the vehicle. It retains the old engine, and this motor sits inside each rear wheel.

It almost seems too good to be true, but a closer reading shows the rotor bolted on one side to the old wheel hub and on the other side to the wheel. The stator meanwhile is bolted to the existing brake caliper mountings. This would lead to a slightly wider track and a greater unsprung weight, but we can see that it would work. Besides the motor there’s a battery pack for the spare wheel well and a set of electrically-powered systems to supply the brake servo vacuum and other services. The idea is that this whole kit could be fitted for 5000 Australian dollars, which is somewhere south of $3200 USD. It’s not perfect and it still involves hauling around the dead weight of an unused engine, but we can see it might still have a niche. If, and that’s a big if, it ever makes it to market, that is.