Really Easy Jacob’s Ladder

There was a time when making a high voltage project like a Jacob’s ladder took time to build or scrounge some kind of high voltage circuit. The neon sign transformer, Marx generator, or voltage multiplier was the hard part of the project. But nowadays you can get cheap high voltage modules that are quite inexpensive. [PaulGetson] picked up one for under $20 and turned it into a quick and easy Jacob’s ladder.

Honestly, once you have high voltage, making a Jacob’s ladder is pretty simple. [Paul] used a cheap plastic box, some coat hanger wire, and some stainless steel bolts.

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DIY Electric Pennyboard Can Hit 40Km/h!!

Home-made transportation is a thriving area for makers to flex their skills. Looking to shorten their university commute, [doublecloverleaf] modded his penny board by adding a motor that can have him zipping along at 40 Km/h!

The electric motor is mounted to the rear truck and delivers power to the wheel gear using a HTD 5 m pulley belt. Finding the deck too flexible to mount the battery pack under, [doublecloverleaf] strengthened it with a pair of carbon-fiber tubes bracketed on the underside. A few custom PCB boards connect ten 5 Ah LiPo battery cells in series to create two, five-cell packs which are kept safe by a thick housing mounted between the board’s trucks. [doublecloverleaf] calculates that they could make up to a 15 km trip on a single charge.

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Musical Proximity Detection Pet Bowls

An essential skill for a maker is the ability to improvise or re-purpose existing materials into new parts. Sometimes, one needn’t make many modifications to create something new, as is the case with [Robin Sterling] and his musical pet bowl.

Originally, it was a sealed pet bowl that opened when the proximity sensors detected an approaching pet. Having helped design the bowl, [Sterling] had a bit of an advantage when he decided to convert it into a theremin/light harp-esque instrument for the company BBQ. He routed the PWM outputs from each of the three proximity sensors (in each of the three bowls) to a small guitar amp, adjusting each sensor’s output to a different frequency. Despite the short amount of time [Sterling] had to practice, it works fairly well!

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Characterizing A Death Ray… Er, Solar Oven

Many of you will probably at some point have looked at a satellite dish antenna and idly wondered whether it would collect useful amounts of heat if you silvered it and pointed it at the sun. Perhaps you imagine a handy source of  solar-cooked hotdogs, or maybe you’re a bit of a pyromaniac.

[Charlie Soeder] didn’t just think about it, he did it. Finding a discarded offset-focus DirecTV dish, he glued a grid of 230 inch-square mirror tiles to it and set to investigating  the concentrated solar energy at its focus. 

Cotton waste, newspaper, and scraps of fabric char and burn with ease. A cigarette is lit almost from end to end, and it burns a hole right through a piece of bamboo. Most of the energy is in the form of light, so transparent or reflective items need a little help to absorb it from something dark. He demonstrated this by caramelizing some sugar through adding a few bits of charcoal to it, once the charcoal becomes hot enough to caramelize the sugar around it the spreading dark colour causes the rest of the sugar to caramelize without further help.

Solar furnace calculations
Solar furnace calculations

To gain some idea of the power of his solar furnace, he recorded a time series of temperature readings as it heated up some water darkened with a bit of charcoal to absorb heat. The resulting graph had a flat spot as a cloud had passed over the sun, but from it he was able to calculate instantaneous power figures from just below 30W to just below 50W depending on the sun.

He records his progress in the video you’ll find below the break. Will we be the only ones casting around for a surplus dish after watching it?

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How Accurate Is Microstepping Really?

Stepper motors divide a full rotation into hundreds of discrete steps, which makes them ideal to precisely control movements, be it in cars, robots, 3D printers or CNC machines. Most stepper motors you’ll encounter in DIY projects, 3D printers, and small CNC machines are bi-polar, 2-phase hybrid stepper motors, either with 200 or — in the high-res variant — with 400 steps per revolution. This results in a step angle of 1.8 °, respectively 0.9 °.

Can you increase the resolution of this stepper motor?

In a way, steps are the pixels of motion, and oftentimes, the given, physical resolution isn’t enough. Hard-switching a stepper motor’s coils in full-step mode (wave-drive) causes the motor to jump from one step position to the next, resulting in overshoot, torque ripple, and vibrations. Also, we want to increase the resolution of a stepper motor for more accurate positioning. Modern stepper motor drivers feature microstepping, a driving technique that squeezes arbitrary numbers of microsteps into every single full-step of a stepper motor, which noticeably reduces vibrations and (supposedly) increases the stepper motor’s resolution and accuracy.

On the one hand, microsteps are really steps that a stepper motor can physically execute, even under load. On the other hand, they usually don’t add to the stepper motor’s positioning accuracy. Microstepping is bound to cause confusion. This article is dedicated to clearing that up a bit and — since it’s a very driver dependent matter — I’ll also compare the microstepping capabilities of the commonly used A4988, DRV8825 and TB6560AHQ motor drivers.

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Hackaday Prize: 20 Projects That Are The Height Of Automation

Automation makes the world go around. Whether it’s replacing elevator attendants with buttons, replacing songwriters with computer algorithms, or giving rovers on Mars the same sense and avoid capability as a Tesla, Automation makes our lives easier and better. Today we’re excited to announce the twenty projects that best demonstrate the possibilities of Automation in the running for the 2016 Hackaday Prize. These projects tackled problems ranging from improving the common stepper motor to flying Lidar around a neighborhood on a gigantic ducted fan.

The winners of the Hackaday Prize automation challenge are, in no particular order:

If your project is on the list, congrats. You just won $1000 for your hardware project, and are now moving up to the Hackaday Prize finals where you’ll have a chance to win $150,000 and a residency at the Supplyframe DesignLab in Pasadena.

Assistive TechnologiesIf your project didn’t make the cut, there’s still an oppurtunity for you to build the next great piece of hardware for The Hackaday Prize. The Assistive Technologies Challenge is currently under way challenging you to build a project that helps others move better, see better, or live better.

We’re looking for exoskeletons, a real-life Iron Man, a better wheelchair, a digital braille display, or the best educational software you can imagine.

Like the Design Your ConceptAnything GoesCitizen Science, and Automation rounds of the the Hackaday Prize, the top twenty projects will each win $1000 and move on to the Hackaday Prize finals for a chance to win $150,000 and a residency at the Supplyframe DesignLab in Pasadena

If you don’t have a project up on Hackaday.io, you can start one right now and submit it to the Hackaday Prize. If you’re already working on the next great idea in assistive technologies, add it to the Assistive Technologies challenge using the dropdown menu on the sidebar of your project page.

The Hackaday Prize is the greatest hardware competition on Earth. We want to see the next great Open Hardware project benefit everyone. We’re working toward that by recognizing people who build, make, and design the coolest and most useful devices around.

Building Better Tube Amps With Heathkit Parts

[Justin] had been trying to find a good tube amp for years, but all the best examples were either expensive or a complete basket case. Instead of buying a vintage stereo tube amp, he decided to build his own using the guts of a Heathkit AA-100, a popular tube amp from the 60s and 70s that doesn’t have a great reputation for sound quality.

This project was based on an earlier project from a decade ago that replicated the very popular Dynaco ST-70 tube amp from parts taken from the Heathkit AA-100. The schematic for this conversion was readily available on the usual tube head message boards, and a few PCBs were available for the input stage.

With the schematic in hand, the next thing for [Justin] to do was get a nice enclosure. High quality tube amps are valued as much for their appearance as they are for their sound quality, and after giving his father-in-law a few sketches, a cherry hardwood chassis stained in a beautiful golden brown appeared on [Justin]’s workbench.

The big iron for this new tube amp was taken directly from the old Heathkit, and a few hours in front of a mill netted [Justin] a chassis panel drilled out for the transformers and tube sockets. The rest of the project was a bit of assembly, point-to-point wiring, and wire management giving [Justin] a fantastic amplifier that will last for another fifty years until someone decides to reuse the transformers.