Image of an imagined DIY onewheel

Open Source Openwheel

The story is one we’ve all lived: We see a piece of commercial technology and we want it, but the price tag makes us wonder if it isn’t made with gold pressed latinum. The object of [Zach]’s desire? A single wheel powered skateboard sold by a company called Onewheel. But as you can see in the video below the break, and his excellent website, Zach took the wallet-light but time-heavy approach and built his own prototype he calls the Openwheel.

Starting with a single powered wheel, [Zach] used aluminum, very large 3D printed pieces, and a really slick off the shelf controller package to control the Openwheel. Balance is handled by the controller, while a massive 48 V LiPo battery is fed through a beefy electronic speed controller that allows advanced features like regenerative braking.

We won’t spoil the results, but [Zach]’s Openwheel came out very nice, even exceeding some specifications of the commercial unit. You’ll want to watch his YouTube series about the build to get an idea of all the work that goes into such a device even as a prototype.

If tank track tread is more your jam, check out this tank track skateboard that we featured some time back!

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Need A Small, Cheap Ammeter? Blinkenlights To The Rescue!

You know how it is. You’ve got that new project running, and while it doesn’t consume much power, it also doesn’t give much indication of whether it’s functioning or just sitting there with a dead battery. What you need is an ammeter to check power consumption, even from across the room. And it just so happens that [Manuka] has Just The Circuit You Need, complete with a demonstration in the video after the break!

Oh sure, you could grab a cheap ammeter at your favorite tool import store or site, but those are bulky and take batteries. You could put in an LED that gets dimmer as voltage drops. But wait- is that the sun shining on it? or is it on? Or has something gone awry and it’s consuming too much power?

What [Manuka] gives us is a circuit that is designed to be built into your project or project’s power supply. Using only an ultra-bright white LED, red blinking LED, PNP transistor, and a diode, the circuit gives a strong visual indication of current consumption by blinking brighter and more frequently as current increases. With a bit of calibration, accurate measurements can be obtained. All of this is made possible by using the Flashing LED as a driver for the ultra-bright LED, which is a pretty slick hack!

Flashing LEDs have a great number of uses, like protecting your family from lions. Yes, really. Got a cool tip for flashing LEDs, blinkenlights, 555’s, or any odd thing that strikes your hackers fancy? Let the tip line know!

Continue reading “Need A Small, Cheap Ammeter? Blinkenlights To The Rescue!”

Ski lift in at a European ski resort

Ski Lift Design Does The Impossible

Tis The Season, for those who are so inclined, to loft themselves to the top of a steep snow-covered hill and then go downhill, really fast. And if something gets in their way, turn. Whether they be on skis, a snowboard, or some other means, getting down usually involves using gravity. Getting up, on the other hand, usually involves a ski lift. And in the video by [kalsan15] after the break, we learn how technology has stepped in to make even the most inaccessible slopes just a lift ride away.

Ski lift in at a European ski resort
A ski lift that can only turn left.

In its most simple form, a ski lift is two pulleys connected by a steel cable. The pulley at the bottom of the hill is powered, and the pulley at the top of the hill serves as an idler. Attached to the steel cable are some means for a person to either sit down or grab a handle and be hoisted to the top of the hill.

Such a simple arrangement works fine if the geography allows for it, but what if there are turns, or there need to be multiple idlers to keep the wire taut but also close to the ground? Again, the most basic ski lifts have limitations. If the cable turns left around the idler, then the attachment for the handle or chair has to be on the right, making a right turn around the idler an impossibility.

How then can this problem be solved? We won’t spoil the outcome, but we recommend checking out [kalsan15]’s video for an excellent description of the problem and the solution that’ll leave you wondering “Why didn’t I think of that!?”

If you don’t find this hacky enough, then take a moment to learn how you too can not just make a gas-powered ski lift for your cabin in the woods, but then ride your slope down on your DIY Ski Bike!

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Virtual Eurorack Based CPU Computes To The Beat Of A Different Drum Module

In Arthur C. Clarke’s 1972 story “Dial F for Frankenstein”, the worlds first global network of phone exchanges was created by satellite link, and events happened that caused the characters in the story to wonder if the interconnected mesh of machinery had somehow become sentient. And that’s what we wondered when we saw this latest virtual CPU construction built by GitHub user [katef] and made from a virtual analog synthesizer software called VCV Rack.

Analogous to a Redstone computer in Minecraft, there’s no physical hardware involved. But instead of making crazy synth sounds for a music project, [katef] has built a functioning CPU complete with an Arithmetic Logic Unit, an adder, and other various things you’ll find in a real CPU such as registers and a clock.

While no mention is made of whether the construct is sentient, [katef] fully documented the build on their GitHub page, and so go check that out for animated pictures, links to more information, and more. It’s quite impressive, if not just a little bonkers. But most good hacks are, right?

We love unique CPU builds, and you might get a kick out of this one made from- that’s right- 555 timers. Thanks to [Myself] on the Hackaday Discord server for the tip, and be sure to send in your favorite outrageous projects to the Hackaday tip line!

Acordeonador, an 555 accordion powered by a CD player based genrator

CD Player Powered 555 Piano Goes Accordion To Plan

Ah yes, the 555 piano project. Be it the Atari Punk Console, or some other 555 based synthesizer, Hackers just love to hear what the 555 can do when attached to a few passives and a speaker. It’s a sound to behold. But for [Berna], that wasn’t quite enough! Below the break, you can see his creation, called the Acordeonador.

A portmanteau of the Spanish words for “Accordion” and Generator”, the Acordeonador does what no project we’ve seen so far can do: It turns a CD drive into a generator for a 555 based synthesizer.

To give the Acordeonador a more analog feeling, a large 4700uf electrolytic capacitor stores just enough energy to make the music generation more than an on/off affair. It’s a great effect, and it works well! Not being one to leave any details out, [Berna] prototyped the build on perf board and then covered the board in what appears to be an wood grained contact paper, giving it that 1970’s dual keyboard electric organ feel.

It really just goes to prove that a 555 project can be the source of a great time! Hackaday is rife with 555 projects, but if you enjoy this, be sure to check out The Most Important Device In the Universe, which is of course powered by a 555. Continue reading “CD Player Powered 555 Piano Goes Accordion To Plan”

A man welds on a chassis

Electric Wheelchair Dump Truck Hack Really Hauls

Have you ever looked at a derelict electric wheelchair and thought “I bet I could make something great with that!” Of course you have- this is Hackaday, after all! And so did [Made in Poland], who managed to get a hold of a broken down electric wheelchair and put the full utility of his well equipped metalworking shop to work. The results? Lets just say it hauls.

What we really enjoyed about the build was that there wasn’t much that couldn’t be done by an average garage hacker with a drill press, angle grinder, and a stick welder. While it’s definitely nicer to have a lathe and a high quality welding table, plasma cutter, and everything in between, nothing that [Made in Poland] did in the video is such high precision that it would require those extensive tools. There may be some parts that would be a lot more difficult, or lower precision, but still functional.

Another aspect of the build is of course the control circuitry and user interface. Keeping the skid steer and castor approach meant that each motor would need to be controllable independently. To achieve this, [Made in Poland] put together a purely electromechanical drive controlled with momentary rocker switches and automotive relays to form a simple H-Bridge for each motor.

Of course you just have to watch until the end, because it really proves that a man will do anything to get out of hauling wood around! Old electric wheelchairs can also make a great base for big robots, as it turns out.

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(Getting Rid Of) The Ghost In The LED

Multiplexing is a very old technology in which control signals are intermixed for the sake of being able to control more devices than there are control signals. For [mihai.cuciuc], the problems started when he multiplexed some very efficient LEDs.

The problem? In two banks of six LEDs each, both LEDs connected to a single Arduino pin would light, even when only one bank was turned on at the ground side. The LED In the bank that was switched on lit brightly, and its corresponding LED in the bank that was off would also be very dimly lit. [mihai] was able to determine that the problem was not due to a leaky transistor, but rather due to a quality of the LEDs themselves.

What is an LED but a diode, and it’s well known that diodes also have capacitance. In fact, this quality is exploited in varactor diodes, a specialty diode whose capacitance can be changed by varying the voltage on the cathode. [mihai] deduced that this capacitance was causing current to flow in the bank that was off. Where was the current going? From the Arduino pin that was on, through its attached LED, and then into the rest of the bank of LEDs, charging them like capacitors. [mihai] hasn’t seen this before, but theorizes that for the latest batch of high efficiency LEDs, this minute current is enough to light the LED through which the current is flowing.

[mihai]’s solution is an elegant hack which he’s made available for your perusal. You might also enjoy this introduction to diode basics by W2AEW. If you have any great diode or LED hacks of your own, be sure to drop us a line!