Fat Tire Bike Turned Hubless

June 24, 2021 by Danie Conradie 45 Comments

Bicycle wheels have looked pretty much the same for over a century, and for very good reason: It works. [The Q] decided to ignore reason for a bit and focus on looks, so he built a fat tire bike without any hubs or spokes.

To make this work, he fabricated two sets of ring shaped “hubs” about the size of the rims, with a series of ball bearings around the circumference for the rims to roll around. The original forks were cut short and welded to a set of brackets that bolt to new hubs. This further complicates the back end as there’s nowhere to attach the sprocket cassette. The original rear hub, cassette and disc brake was moved to the inside of the frame. This drives the rear wheel using a second chain attached to a large ring sprocket mounted directly on the rim. The front brake was simply eliminated.

While this new design won’t be taking on existing bicycles, we doubt practicality was a priority in the build. It’s definitely a head turner, and we can’t help but see an opportunity to go even further and build a TRON bicycle.

Just recently, [The Q] turned another fat tire bike into an all-wheel-drive extreme off-roader. For another pedal-powered head turner, check out the strandbeest bicycle.

Roller Skating, Wile E. Coyote-Style

June 13, 2021 by Kristina Panos 36 Comments

They say you learn something new every day, and they’re usually right about that. Today’s tidbit is that just anybody (including [Ian Charnas]) can exchange money for jet engines, no questions asked. Scary, huh? So once [Ian] secured the cutest little engine, he took a poll regarding possible uses for it. Jetpack rollerskating won, that’s obvious enough. So let’s get into those details.

[Ian] procured this particular jet engine from an outfit called CRX Turbines. It tops out at 98,000 RPM and 30 kg (66 lbs.) of thrust. Essentially, he is pulsing the engine’s ECU with PWM from an Adafruit RadioFruit and controlling it with a pair of stripped drills that are just being used for their convenient grips and switches. One is wired as a dead man’s switch, and the other controls the throttle signal.

In order to run the thing and test the thrust a bit before strapping it on his back, [Ian] went about this the smart way and welded together a sliding stand. And he didn’t use just any old Jansport backpack, he welded together a frame and roll cage for the engine and attached it to a full-body harness. There’s also a heat shield to keep his backside from catching fire.

At first he tested the jet pack with shoes instead of skates to make sure it was going to behave as he predicted. Then it was time to bust out the roller skates. [Ian] achieved a top speed of 17 MPH before losing his balance, but he knew it could go faster, so he invited some roller derby skaters to try it out. One of them went over 30 MPH! Be sure to check it out in the build and demo video after the break.

If you’re at all familiar with [Ian]’s videos, you know that he usually raffles off the build and gives the money to charity. Well, not this time! That wouldn’t be prudent. Instead, he’s going to choose the best suggestion for what to attach it to, build it, and raffle that off. Hopefully, he stays away from airports with that thing on his back.

Continue reading “Roller Skating, Wile E. Coyote-Style” →

A Self-Driving Bicycle Is Something To Marvel At

June 10, 2021 by Lewin Day 44 Comments

One of the most annoying things about bicycles is that they don’t stay up on their own, especially when they’re stationary. That’s why they come with stands, after all. That said, if you had plenty of advanced electronic and mechanical equipment fitted to one, you could do something about that, and that’s just what [稚晖君] did.

The video of the project comes without subtitles or any translation, but the gist of it is this. A reaction wheel is fitted to the seat tube, along with a motor which can turn the handlebars via a linkage attached to the head stem. There’s also a motor to drive the bicycle forward via a friction drive to the rear wheel. Combine these with an inertial measurement unit and suitable control system, and you have a bike that can balance while standing perfectly still.

The performance of the system is impressive, and is even able to hold the bike perfectly upright while balanced on a fence rail. Thanks to an onboard camera and LIDAR system, the bike can also drive itself around with no rider on board, which is quite a spooky image. Find a way to do the same while hiding the extra mechanics and you’d have one hell of a Halloween display.

Similar projects have been attempted in the past; we featured a self-balancing bike built as a university project back in the distant past of 2012. Video after the break.

Continue reading “A Self-Driving Bicycle Is Something To Marvel At” →

Tractors And The Right To Repair: It’s Going Global

June 8, 2021 by Jenny List 65 Comments

For more than a few years now, we’ve been covering the saga of tractors from the larger manufacturers on which all components are locked down by software to the extent that they can only be replaced by officially sanctioned dealers. We’re thus pleased to see a couple of moments when the story has broken out of the field of a few farmers and right-to-repair geeks and into the mainstream. First up: a segment on the subject from NPR is worth a listen, as the US public radio station interviews a Montana farmer hit by a $5k fuel sensor on his John Deere as a hook form which to examine the issue. Then there is a blog post from the National Farmers Union, the body representing UK farmers, in which they too lay out the situation and also highlight the data-grabbing aspects of these machines.

Continue reading “Tractors And The Right To Repair: It’s Going Global” →

Ryobi Power Packs As Ebike Batteries

June 7, 2021 by Jenny List 42 Comments

By now, the process of creating custom lithium-ion battery packs is well-known enough to be within the reach of most makers. But it’s not a path without hazard, and mistakes with battery protection and management can be costly. Happily for those who are apprehensive on the battery front there’s a solution courtesy of a group of engineering students from the University of Pittsburgh. Their project was to convert a pedal bicycle to electric assisted power, and in doing so they didn’t make their own pack but instead used off-the-shelf 40V Ryobi power tool packs.

The bike conversion is relatively conventional with the crank replaced by a crank and motor assembly, and a pair of the Ryobi packs in 3D-printed holders on the frame. The value in this is in its reminder that these packs have evolved to the point at which they make a viable alternative to a much more expensive bike-specific pack, and that their inclusion of all the balancing and protection circuitry make them also a much safer option than building your own pack. The benefits of this are immense as they bring a good-quality conversion within reach of many more bicycle owners, with all parts being only a simple online order away. Take a look at the video below the break for more details.

Those Ryobi cells certainly seem to have carved themselves a niche in our community!

Continue reading “Ryobi Power Packs As Ebike Batteries” →

Baby C-17 Sends Imaginations Soaring

June 6, 2021 by Roger Cheng 17 Comments

The C-17 Globemaster III is a military cargo jet that can carry what their commercial counterparts can’t, to places those other planes can’t go. The people who keep these planes flying are proud of their capable airlifter, but it’s hard to show them off. Solution: build a scaled-down version more suitable for driving off base for a parade down Main Street and other community events.

While the real thing was built under an expensive and contentious military procurement process, the miniature was built with volunteer labor using castoff materials. The volunteer force included maintenance crew whose job is to know the C-17 inside and out. Combined with fabrication skills that comes with the job, the impressive baby plane faithfully copied many curvatures and details from full-sized originals. (Albeit with some alteration for its cartoony proportions.) Underneath are mechanicals from a retired John Deere Gator utility vehicle. They usually resemble a large golf cart except with a cargo bed and more rugged suspension. Basically they are to golf carts as a C-17 is to a 767. Amusingly, the little plane has its own rear loading ramp, superficially preserving the cargo-carrying capacity of the original Gator chassis.

Interior features continue, though the official picture gallery doesn’t show them. There is a flight deck with control panels and various sights and sounds to keep visitors entertained. Enough details were poured into the exhibit that some people had to ask if the little plane can fly, and the answer is a very definite no. The wings, and the engine pods mounted to them, are only for show carrying The Spirit of Hope, Liberty & Freedom. It is quite a long official name for such a short stubby thing.

We always love to admire impressively put-together miniatures, and not all projects require skill of aircraft mechanics. Like this very approachable miniature forklift project. But there are plenty of other projects whose skills put us in awe, like this remote-control car powered by a miniature V-10 engine.

[via The Museum of Flight]

The Many Levels Of Autonomous Motoring

May 28, 2021 by Jenny List 40 Comments

For years now we have been told that self-driving cars will be the Next Big Thing, and we’ve seen some companies — yes, Tesla but others too — touting current and planned features with names like “Autopilot” and “self-driving”. Cutting through the marketing hype to unpacking what that really means is difficult. But there is a standard for describing these capabilities, assigning them as levels from zero to five.

Now we’re greeted with the news that Honda have put a small number of vehicles in the showrooms in Japan that are claimed to be the first commercially available level 3 autonomous cars. That claim is debatable as for example Audi briefly had level 3 capabilities on one of their luxury sedans despite having few places to sell it in which it could be legally used. But the Honda Legend SENSING Elite can justifiably claim to be the only car on the market to the general public with the feature at the moment. It has a battery of sensors to keep track of its driver, its position, and the road conditions surrounding it. The car boasts a “Traffic Jam Pilot” mode, which “enables the automated driving system to drive the vehicle under certain conditions, instead of the driver, such as when the vehicle is in congested traffic on an expressway“.

Sounds impressive, but just what is a level 3 autonomous car, and what are all the other levels?

Continue reading “The Many Levels Of Autonomous Motoring” →