All-Wheel Drive Bicycle Using Hand Drill Parts

May 26, 2021 by Danie Conradie 33 Comments

A skilled mountain biker can cross some extreme terrain, but [The Q] thought there might be room for improvement, so he converted a fat bike to all-wheel drive.

The major challenge here is transferring pedal power to the front wheels, especially around the headset. [The Q] solved this by effectively building a differential from the parts of a very old hand drill. Since the front wheel needs to rotate at the same speed as the rear, one long chain loops from the rear wheel to the headset, tensioned by a pair of derailleurs. This front sprocket turns a series of spur gears and bevel gear arranged around the headset, which transfers the power down to the front wheel via another chain.

It would be interesting to feel what the bike rides like in soft sand, mud, and over rocks. We can see it has some advantages in those conditions but were unsure if it would be enough to offset the penalty in weight and complexity. The additional chains and gears certainly look like they’re asking to catch foliage, clothing, and maybe even skin. However, we suspect [The Q] was more likely doing it for the challenge of the build, which we can certainly appreciate. With the rise of e-bikes, adding a hub motor to the front wheel seems like a simpler option.

We’ve seen several interesting bicycle hacks over the years, including a strandbeest rear end, 3D printed tires and an automatic shifter. Continue reading “All-Wheel Drive Bicycle Using Hand Drill Parts” →

Putting LEDs In Motorcyle Tail Light Shows How Trivial Becomes Tough

May 25, 2021 by Donald Papp 55 Comments

[Maarten Tromp]’s replacement of his motorcycle’s tail light with LED equivalents is a great example of something that every hacker learns sooner or later: interfacing to and working around existing parts can turn a trivial-seeming task into a much bigger job than expected. The more one has to work within the constraints of an existing system, the more opportunities there are for roadblocks and surprise issues to stall progress, and this project is a great example of that.

[Maarten]’s 1999 Honda ST1100 Pan European motorcycle had no aftermarket options for an LED rear light assembly, and he wasn’t too keen on just installing a generic module to replace the original. Instead, he resolved to purchase and disassemble a used factory assembly, and replace the incandescent lamps with some equivalent LEDs. Replacing bulbs with LEDs sounds easy, but doing the job right took [Maarten] almost two weeks in the end.

Problems started early with simple things like how to open up the light assembly itself. The unit isn’t user-serviceable and isn’t intended to be opened, and the parts are sealed shut with a waxy substance. Fortunately, heat does the trick. Another early hitch was the curved base of the light assembly, which made mounting flat perfboard or veroboard a challenge. In the end, [Maarten] settled on a triangular grid of high-brightness LEDs, driven with LM317 regulators configured as constant-current supplies, mounted on some protoboard cut to fit the unique curve of the assembly. The result accepts the wide voltage range of the motorcycle’s battery (from 10.5 V to 14.5 V) and can still function even if some individual LEDs stop working.

The project has one more example of how working around existing hardware can be a pain. [Maarten] had originally intended to swap out the turn signal lamps for LEDs as well, but there is a glitch. The motorcycle’s turn signal relay will do a fast blink pattern if burnt-out turn signal lamps are detected. Since LEDs consume considerably less current than the original bulbs, the relay will remain stuck in the fault condition. There are a few different ways around this, but it’s a problem for another day. For now, the tail light LED replacement is a success.

Working around existing hardware frequently brings unexpected challenges, but when safety systems (such as lights on a vehicle) are involved, it’s extra-important to make sure things are done right.

Ground Effect Drone Flies Autonomously

May 24, 2021 by Bryan Cockfield 14 Comments

There are a number of famous (yet fictional) sea monsters in the lakes and oceans around the world, but in the Caspian Sea one turned out to be real. This is where the first vehicles specifically built to take advantage of the ground effect were built by the Soviet Union, and one of the first was known as the Caspian Sea Monster due to the mystery surrounding its discovery. While these unique airplane/boat hybrids were eventually abandoned after several were built for military use, the style of aircraft still has some niche uses and can even be used as a platform for autonomous drones.

This build from [Think Flight] started off as a simple foam model of just such a ground effect vehicle (or “ekranoplan”) in his driveway. With a few test flights the model was refined enough to attach a small propeller and battery. The location of the propeller changed from rear-mounted to front-mounted and then back to rear-mounted for the final version, with each configuration having different advantages and disadvantages. The final model includes ~~an Arudino running~~ an autopilot program called Ardupilot, and with an air speed sensor installed the drone is able to maintain flight in the ground effect and autonomously navigate pre-programmed waypoints around a lake at high speed.

For a Cold War technology that’s been largely abandoned by militaries in favor of other modes of transportation due to its limited use case and extremely narrow flight tolerances, ground effect vehicles are relatively popular as remote controlled vehicles. This RC ekranoplan used the same Ardupilot software but paired with a LIDAR system instead of GPS to navigate its way around its environment.

Thanks to [TTN] for the tip!

Continue reading “Ground Effect Drone Flies Autonomously” →

Custom Keyfob Fixes Mazda Design Mistake

May 24, 2021 by Bryan Cockfield 60 Comments

While Mazda has made some incredible advances in fuel efficient gasoline engines over the past few years, their design group seems to have fallen asleep at the wheel in the meantime, specifically in regards to the modern keyfob design. The enormous size and buttons on the side rather than the face are contrary to what most people need in a keyfob: small size and buttons that don’t accidentally get pressed. Luckily, though, the PCB can be modified with some effort.

This particular keyfob has a relatively simple two-layer design which makes it easy to see where the connections are made. [Hack ‘n’ Tink] did not need the panic button or status LED which allowed him to simply cut away a section of the PCB, but changing the button layout was a little trickier. For that, buttons were soldered to existing leads on the face of the board using 30-gage magnet wire and silicone RTV. From there he simply needed to place the battery in its new location and 3D print the new enclosure.

The end result is a much smaller form factor keyfob with face buttons that are less likely to accidentally get pressed in a pocket. He also made sure that the battery and button relocation wouldn’t impact the antenna performance. It’s a much-needed improvement to a small but crucial part of the car; the only surprise is that a company that’s usually on point with technology and design would flop so badly on such a critical component.

Thanks to [Brian] for the tip!

Continue reading “Custom Keyfob Fixes Mazda Design Mistake” →

Scratch Built Tricycle Maximizes Fuel Efficiency

May 16, 2021 by Bryan Cockfield 27 Comments

While the bicycling community is welcoming an influx of electric bikes, there’s a group of tuners on the fringes that are still intent on strapping gas motors of all sizes to bicycles and buzzing down the roads in a loud and raucous fashion. Kits are readily available and are much cheaper than comparable e-bike kits, and with a little bit of work it’s possible to squeeze a lot of excitement from these small motors. With a lot of work, though, you might end up with something like this incredibly fuel efficient and fully customized reverse trike from [Paul Elkins].

The entire goal with this build was fuel efficiency, so the plan is to eventually enclose the vehicle in aerodynamic fairings, most likely using his favorite material, Coroplast. The frame itself is completely hand-made from square tube and welded by [Paul] himself to his own custom specifications. He bolts on a suspension and custom steering rack with levers to control the two front wheels, and the small engine and gas tank are attached to the back above the single drive wheel. The engine hadn’t been started in ten years, but once he got it all put together, it started right up and he was able to take his latest prototype out on the road for a test drive.

While the build isn’t completely finished, the video below (eleventh so far in the build log) is far enough along to show the fruits of years of [Paul]’s labor. It’s taken a while to get a design that worked like he wanted, but with this iteration, he finally has what he was looking for.

Continue reading “Scratch Built Tricycle Maximizes Fuel Efficiency” →

A DIY Enclosed Motorcycle To Keep You Dry In The Rain

May 5, 2021 by Danie Conradie 41 Comments

Motorcyclist’s vulnerability to bodily harm and weather has spawned several enclosed motorcycle designs over the years. Fascinated by the idea, [Meanwhile in the garage] finally got around to building his own. (Video, embedded below.)

The vehicle started life as a 125cc scooter, stripped of all the unnecessary bits, he welded a steel cockpit onto it. A windshield, doors, and side windows were also added. The ends of the handlebars were cut off and reattached at 90 degrees to fit inside the narrow cockpit. A pair of retractable “training wheels” keep the vehicle upright and at slow speeds.

Legalities aside, we can’t help but think that the first test drives should not have been on a public road. It almost ended in disaster when a loose axle nut on the front wheel caused steering oscillations which caused the vehicle to tip over. Fortunately, there were no injuries and only light cosmetic damage, so a more successful test followed the first.

While many companies have tried, enclosed motorcycles have never achieved much commercial success. Probably because they inhabit a no-mans-land between the rush and freedom of riding a motorcycle and the safety and comfort of a car.

For some less extreme conversion, check out this electric motorcycle, or a rideable tank track.

Continue reading “A DIY Enclosed Motorcycle To Keep You Dry In The Rain” →

Hoverboard Turned Heavy Duty Remote Control Rover

May 3, 2021 by Tom Nardi 20 Comments

They might not be the hoverboards we were promised in Back to the Future II, but the popular electric scooters that have commandeered the name are exciting pieces of tech in their own way. Not because we’re looking to make a fool of ourselves by actually riding one, but because they’re packed full of useful hardware that’s available for dirt cheap thanks to the economies of scale and the second-hand market.

In his latest video, the ever resourceful [MakerMan] turns a pair of hoverboards into a capable remote controlled mobile platform perfect for…well, whatever you want to move around. Its welded steel construction is certainly up for some heavy duty tasks, and while we can’t say we’d ever tow a SUV with it as shown in the video below, it’s nice to know we’d have the option.

The project starts by liberating the four wheel motors from the scooters and carefully cutting down the frame to preserve the mounting hardware. These mounts are ultimately welded to the frame of the rover, with a piece of diamond plate screwed down on top. On the bottom, [MakerMan] mounts the two control boards and a custom fabricated 36 V battery pack.

He doesn’t go into any detail on how he’s interfacing the RC hardware with the motor controllers, but as we’ve seen with past hacks, there’s open source firmware replacements for these boards that allow them to be controlled by external inputs. Presumably something similar is being used here, but we’d be interested to hear otherwise. Of course you could swap the RC hardware out for a microcontroller or Raspberry Pi if you were looking to make some kind of autonomous rover.

Don’t have a welder or convenient collection of scrap steel laying around? No worries. Prolific tinkerer [Aaron Christophel] put something very similar together using bolted aluminum extrusion.

Continue reading “Hoverboard Turned Heavy Duty Remote Control Rover” →