Every hacker out there is familiar with the zaps and sizzles of the Tesla coil, or the crash and thunder of lighting strikes on our hallowed Earth. These phenomena all involve the physics of plasma, a subject near and dear to Jay Bowles’s heart. Thus, he graced Remoticon 2021 with a enlightening talk taking us on a Dip Into the Plasmaverse.
Jay’s passion for the topic is obvious, having fallen in love with high voltage physics as a teenager. He appreciated how tangible the science was, whether it’s the glow of neon lighting or the heating magic of the common microwave. His talk covers the experiments and science that he’s studied over the past 17 years and in the course of running his Plasma Channel YouTube channel.Continue reading “Remoticon 2021 // Jay Bowles Dips Into The Plasmaverse”→
Most of our projects are, to some extent, an exercise in glitch-reduction. Whether they’re self-inflicted software or hardware mistakes, or even if the glitches in question come from sources beyond our control, the whole point of the thing is to get it running smoothly and predictably.
That’s not always the case, though. Sometimes inducing a glitch on purpose can be a useful tool, especially when reverse engineering something. That’s where this low-cost electromagnetic fault injection tool could come in handy. EMFI is a way to disrupt the normal flow of a program running on an embedded system; properly applied and with a fair amount of luck, it can be used to put the system into an exploitable state. The PicoEMP, as [Colin O’Flynn] dubs his EMFI tool, is a somewhat tamer version of his previous ChipSHOUTER tool. PicoEMP focuses on user safety, an important consideration given that its business end can put about 250 volts across its output. Safety features include isolation for the Raspberry Pi Pico that generates the PWM signals for the HV section, a safety enclosure over the HV components, and a switch to discharge the capacitors and prevent unpleasant surprises.
In use, the high-voltage pulse is applied across an injection tip, which is basically a ferrite-core antenna. The tip concentrates the magnetic flux in a small area, which hopefully will cause the intended glitch in the target system. The video below shows the PicoEMP being used to glitch a Bitcoin wallet, as well as some tests on the HV pulse.
If you’re interested in the PicoEMP and glitching in general, be sure to watch out for [Colin]’s 2021 Remoticon talk on the subject. Until that comes out, you might want to look into glitching attacks on a Nintendo DSi and a USB glitch on a Wacom tablet.
When he’s not busy with his day job as professor of computer and automotive engineering at Weber State University, [John Kelly] is a prolific producer of educational videos. We found his video tracing out the 22+ meters of high voltage cabling in a Tesla Model S (below the break) quite interesting. [John] does warn that his videos are highly detailed and may not be for everyone:
This is not the Disney Channel. If you are looking to be entertained, this is not the channel for you.
We ignored the warning and jumped right in. The “high” voltages in the case of an electric vehicle (EV) like the Model S is approximately 400 volts. Briefly, external input via the charge connector can be single or three phase, 120 or 250 VAC, depending on your region and charging station. This get boosted to a nominal 400 VDC bus that is distributed around the various vehicle systems, including the motors and the battery pack.
Rear Modules
Charge receptacle
On-board charger module
Rapid splitter
Rear motor inverter
Front Modules
High voltage junction block
Cabin air heater
DC to DC converter
Battery coolant heater
Air conditioning compressor
Front motor inverter
He goes through each module, showing in detail the power routing and functionality, eventually assembling the whole system spanning two work benches. We liked his dive into the computer-controlled fuse that recently replaced the standard style one, and were impressed with his thorough use of labels.
If you’ve ever been curious about the high voltage distribution of a EV, grab some popcorn and check out this video. Glancing through his dozens of playlists, [John]’s channel would be a good place to visit if you’re interested any topic related to hybrids and electric vehicles, drive trains, and/or transmissions. We’ve written about some Tesla teardowns before, the Model 3 and the Model S battery packs. Have you worked on / hacked the high voltage system in your EV? Let us know in the comments below.
High-voltage experimenters have been using automotive ignition coils to generate impressive sparks in the home lab for decades, and why not? They’re cheap, easily obtainable, and at the end of the day, producing sparks is literally what they’re designed to do. But that doesn’t mean there isn’t room for improvement.
In his latest Plasma Channel video [Jay Bowles] revisits this classic experiment, bringing to bear the considerable high-voltage experience he’s gained over the last several years. Building on an earlier setup that used a single Honda ignition coil, this new dual-coil version can produce up to 60,000 volts and is driven by a cleaner and more reliable circuit based on the iconic 555 timer. A pair of potentiometers on the front of the driver can adjust its square wave output from 1 to 10 kilohertz manually, while a commercial Bluetooth audio receiver tied into the 555 circuit allows the output to be modulated by simply playing audio from a paired device.
It probably won’t come as much surprise to find that a blast of hot plasma can be used to sterilize a surface. Unfortunately, said surface is likely going to look a bit worse for wear afterwards, which limits the usefulness of this particular technique. But as it turns out, it’s possible to generate a so-called “cold” plasma that offers the same cleansing properties in a much friendlier form.
Cold plasma stopped bacterial growth in the circled area.
[Jay] takes viewers through a few of the different approaches he tried before finally settling on the winning combination of a glass pipette with a copper wire run down the center. When connected to a party store helium tank and the compact Slayer Exciter coil he built last year, the setup produced a focused jet of plasma that was cool enough to touch.
It’s beautiful to look at, but is a pretty light show all you get for your helium? To see if his device was capable of sterilizing surfaces, he inoculated a set of growth plates with bacteria collected from his hands and exposed them to the cold plasma stream. Compared to the untreated control group the reduction in bacterial growth certainly looks compelling, although the narrow jet does have a very localized effect.
If you’re just looking to keep your hands clean, some soap and warm water are probably a safer bet. But this technology does appear to have some fascinating medical applications, and as [Jay] points out, the European Space Agency has been researching the concept for some time now. Who knows? In the not so distant future, you may see a similar looking gadget at your doctor’s office. It certainly wouldn’t be the first time space-tested tech came down to us Earthlings.
Finding high voltage capacitors can be tricky. Sure, you can buy these capacitors, but they are often expensive and hard to find exactly what you want. [RachelAnne] needed some low-value variable capacitors that would work at 100 kV. So she made some.
Instead of fabricating the plates directly, these capacitors use laminations from a scrap power transformer. These usually have two types of plates, one of which looks like a letter “E” and the other just like a straight bar. For dielectric, the capacitors use common transparency film.
The average Hackaday user could probably piece together a rough model of a simple DC motor with what they’ve got kicking around the parts bin. We imagine some of you could even get a brushless one up and running without too much trouble. But what about an electrostatic corona motor? If your knowledge of turning high voltage into rotational energy is a bit rusty, let [Jay Bowles] show you the ropes in his latest Plasma Channel video.
Like many of his projects, this corona motor relies on a few sheets of acrylic, a handful of fasteners, and a healthy dose of physics. The actual construction and wiring of the motor is, if you’ll excuse the pun, shockingly simple. Of course part of that is due to the fact that the motor is only half the equation, you still need a high voltage source to get it running.
An earlier version of the motor ended up being too heavy.
In this case, [Jay] is revisiting his earlier experiments with atmospheric electricity to provide the necessary jolt. One side of the motor is connected to a metallic mesh electrode that’s carried 100 m into the air by a DJI Mini2 drone, while the other side is hooked up to several large nails driven into the ground.
The potential between the two gets the motor spinning, and makes for an impressive demonstration, but it’s not exactly the most practical way to experiment with your new corona motor. If you’d rather get it running on the workbench, he also shows that a more traditional high voltage source like a Van de Graaff generator will do the job nicely. As an added bonus, it can even power the device wirelessly from a few feet away.
So what can you do with a corona motor? While [Jay] is quick to explain that these sort of devices aren’t exactly known for their torque, he does show that his motor is able to lift a 45 gram weight suspended from a string. That’s frankly more power than we expected, and makes us wonder if there is some quasi-practical application for this contraption. If there is we suspect it’ll be featured in a future Plasma Channel video, so stay tuned.
