Edge-Mounted LEDs Make This Spherical POV Look Fantastic

For as many of them as we’ve seen, we still love a good persistence of vision display project. There’s something fascinating about the combination of movement and light creating the illusion of solid surfaces, and there’s always fun to be had in electromechanical aspects of a POV build. This high-resolution spherical POV display pushes all those buttons, and more.

Called “Flicker” for obvious reasons by its creator [Dan Foisy], this POV display started with a pretty clear set of goals in terms of resolution and image quality, plus the need to support animated images, all in a spherical form factor. These goals dictated the final form of the display — a PCB disc spinning vertically. The shaft has the usual slip rings for power distribution and encoders for position feedback. The PCB, though, is where the interesting stuff is.

[Dan] chose to use an FPGA to slice and dice the images, which are fed from a Raspberry Pi’s HDMI port, to the LED drivers. And the LEDs themselves are pretty slick — he found parts with 1.6 mm lead spacing, making them a perfect fit for mounting on the rim of the PCB rather than on either side. A KiCAD script automated the process of laying out the 256 LEDs and their supporting components as evenly as possible, to avoid imbalance issues.

The video below shows Flicker in action — there are a few problem pixels, but on the whole, the display is pretty stunning. We’ve seen a few other spherical POV displays before, but none that look as good as this one does.

Continue reading “Edge-Mounted LEDs Make This Spherical POV Look Fantastic”

This Week In Security: SolarWinds And FireEye, WordPress DDoS, And Enhance!

The big story this week is Solarwinds. This IT management company supplies network monitoring and other security equipment, and it seems that malicious code was included in a product update as early as last spring. Their equipment is present in a multitude of high-profile networks, like Fireeye, many branches of the US government, and pretty much any other large company you can think of. To say that this supply chain attack is a big deal is an understatement. The blame has initially been placed on APT42, AKA, the Russian hacking pros.

The attack hasn’t been without some positive effects, as Fireeye has released some of their internal tooling as open source as a result. Microsoft has led the official response to the attack, managing to win control of the C&C domain in court, and black-holing it.

The last wrinkle to this story is the interesting timing of the sale of some Solarwinds stock by a pair of investment firms. If those firms were aware of the breech, and sold their shares before the news was made public, this would be a classic case of illegal insider trading. Continue reading “This Week In Security: SolarWinds And FireEye, WordPress DDoS, And Enhance!”

Building A Smash Bros. Controller With Keyswitches

When it comes to competitive fighting games, having the right controller in your hands can make the difference between victory and defeat. Many tournaments have strict rules around controllers for this very reason. [Akaki Kuumeri] has recently put together a custom controller, aimed at maximising performance in Super Smash Brothers: Ultimate on the Nintendo Switch. (Video, embedded below.)

The build is assembled in an attractive 3D-printed body, made to be reminiscent of the original Nintendo Entertainment System controller. Inside, a cheap third-party Gamecube controller is used to interface with the console. Mechanical keyboard switches are used to replace the buttons and even the analog sticks, with a special modifier key that enables walking and running across the stage. This is pulled off with a handful of resistors emulating the intermediate position of the analog sticks, and makes pulling off advanced combos easier.

It’s a fun build, and we can imagine the precise digital key inputs having some benefits over analog controls. It also pays to note that such a build wouldn’t be as easy without the ready supply of mechanical key switches thanks to the custom keyboard subculture. We’ve seen these satisfying switches cropping up in many controller builds in recent times.

Continue reading “Building A Smash Bros. Controller With Keyswitches”

Stacked Material Makes Kitchen Temperature Superconductors

Belgian, Italian, and Australian researchers are proposing that by stacking semiconductor sheets, they should be able to observe superconducting behavior at what is known as “kitchen temperature” or temperatures you could get in a household freezer. That’s not quite as good as room temperature, but it isn’t bad, either. The paper is a bit technical but there is a very accessible write-up at Sci-Tech Daily that gives a good explanation.

Superconductors show no loss but currently require very cold temperatures outside of a few special cases. The new material exploits the idea that an electron and a hole in a semiconducting material will have a strong attraction to each other and will form a pair known as an exciton. Excitons move in a superfluid state which should exhibit superconductivity regardless of the temperature. However, the attraction is so strong that in conventional materials, the excitons only exist for the briefest blip of time before they cancel each other out.

Continue reading “Stacked Material Makes Kitchen Temperature Superconductors”

900-Degree Racing Wheel Helps You Nail The Apex

There are many racing wheels on the market for the budding sim enthusiast. Unfortunately, lower end models tend to have a limited range of motion and ship with cheap plastic wheels that don’t feel good in the hand. As always, if what’s on the shelf doesn’t meet your needs, you can always build your own. [ilge]’s DIY racing wheel build is a great example of how to go about it. 

It’s a no-frills build, with an Arduino Leonardo doing the USB Human Interface Device duties in this case. It reads a standard 10K potentiometer via an analog input to determine wheel position. To enable a realistic 900 degrees of motion, unlike the standard 270 degree rotation of the potentiometer, [ilge] uses 3D printed gears of 15 and 54 degrees respectively. This also has the benefit of allowing the wheel to be mounted to a stout bearing for smooth motion. The steering wheel itself is a high quality drift wheel from MOMO, and the benefit of building your own setup is that you can choose whatever wheel you like to taste.

It’s a simple build both mechanically and electronically speaking, but one that serves as a great entry into building a DIY sim for the beginner. We’d love to see further upgrades towards force feedback, or even shift paddles added on the back. Those looking to go all out can even consider building a motion platform. Video after the break.

Continue reading “900-Degree Racing Wheel Helps You Nail The Apex”

BASH Template Promises Safer Scripts

Many bash scripts start out as something quick and dirty but then become so useful that they live for years, indeed sometimes seeing more use than our traditional programs. Now that you can even run bash well under Windows (although, you’ve always been able to run it there if you tried), there are even more opportunities for your five-minute bash script to proliferate. [Maciej] decided he was tired of always having to patch up his quick and dirty scripts to be more robust, so he created (and shared) his boilerplate template for scripts.

Probably most of us have at least some basic template we start with, even if it just our last script project. What’s nice about [Maciej’s] template is that he documents what’s going on with each part of it. It is also relatively short without a lot of excess stuff. Of course, you’ll probably customize it, but it is a great place to start.

Continue reading “BASH Template Promises Safer Scripts”

Hypercar Valve Technology On A Harbour Freight Engine

The inlet and exhaust valve timing of a piston engine plays a large role in engine performance. Many modern automotive engines have some sort of variable valve timing, but the valves are still mechanically coupled together and to the crankshaft. This means that there is always a degree of performance compromise for various operating conditions. [Wesley Kagan] took inspiration from Koenigsegg’s camless Freevalve technology, and converted a Harbour Freight engine to camless technology for individual valve control.

By eliminating the traditional camshaft and giving each valve its actuator, it is possible to tune valve timing for any specific operating condition or even for each cylinder. A cheap single-cylinder engine is a perfect testbed for the garage hacker. [Wesley] removed the rocker arms and pushrods, and replaced the stock rocker cover with a 3D printed rocker cover which contains two small pneumatic pistons that push against the spring-loaded valve stems. These pistons are controlled by high-speed pneumatic solenoid valves. A reference timing signal is still required from the crankshaft, so [Wesley] built a timing system with a 3D printed timing wheel containing a bunch of embedded magnets and being sensed by a stationary Hall effect sensor. An Arduino is used to read the timing wheel position and output the control signals to the solenoid valves. With a rough timing program he was able to get the engine running, although it wouldn’t accelerate.

In the second video after the break, he makes a digital copy of the engine’s existing camshaft. Using two potentiometers in a 3D printed bracket, he measured push rod motion for a complete engine cycle. He still plans to add position sensing for each of the valves, and after a bit more work on the single-cylinder motor he plans to convert a full-size car, which we are looking forward to.

People have been tinkering with cars in their garage for as long as cars have existed. [Lewin Day] has been doing a series on how to get into tinkering with cars yourself. With all the electronics in modern automobiles, messing around with their software has become a growing part of this age-old pastime. Continue reading “Hypercar Valve Technology On A Harbour Freight Engine”