Trill: Easy Positional Touch Sensors For Your Projects

September 16, 2019 by Ted Yapo 8 Comments

Creating capacitive touch-sensitive buttons is easy these days; many microcontrollers have cap-sense hardware built-in. This will work for simple on/off control, but what if you want a linear, position-sensitive input, like you’d find on a computer touchpad or your smartphone screen? Not so easy — at least until now. Trill is a family of capacitive touch sensors you can add to your projects as a linear slider, a square touchpad, or by creating your own touch surface.

Trill was created by the same team that designed Bela, an embedded platform for low-latency interactive applications, especially with audio. The new trio of Trill sensors rely on capacitive sensing to track finger movement, and communicate over I2C with your microcontroller or development board of choice. The Trill I2C library targets Arduino and Bela, but should be easy to port to any I2C host.

The hardware and software are both open-source — or will be as the Kickstarter that launched this morning has already met its goal. The firmware for the Cypress CY8C20636A (PDF) controller that powers these sensors will be released CC-BY-NC-SA. But, starting with the controller itself sounds like a lot of work that Trill has already done for you, so let’s have a look at what we know so far, along with a healthy dose of speculation.

Continue reading “Trill: Easy Positional Touch Sensors For Your Projects” →

Norovirus Smartphone: Using Megapixels And Microfluidics To Fight The Other Kind Of Virus Infection

September 10, 2019 by Dan Maloney 8 Comments

Chances are pretty good that at some time in your life, you’ve crossed paths with a norovirus. And chances are that you remember the encounter vividly, or at least its aftermath. I recall a run-in with the bug one Christmas, when my parents brought over more than just toys for the kids when they visited. Within a day, everyone in the house was sharing the joy. Twas the season; they don’t call it the winter vomiting bug for nothing.

Most of the 685 million norovirus infections each year resolve after a few miserable days, but some require hospitalization and 200,000 of them result in death, mainly from dehydration and mainly children. An easy to use, cheap, and accurate means of detecting the virus in the field would be quite a boon to public health. And soon, smartphones may be able to do just that.

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This CT Scan Of A PCB Is The Accidental ASMR We Didn’t Know We Needed

September 9, 2019 by Daniel Bogdanoff 13 Comments

At risk of getting any ASMR buffs who might be reading cranky because there’s no audio, [Chris], or [@no1089] on Twitter, has gifted us with this visually stunning scan of his Maxim MAX86160 in-ear heart monitor mounted on a rigidflex PCB. You can take a look, in the video below the break.

If you’re wondering why anyone would scan a board, other than boredom, know that it’s actually quite common. X-Ray machines are commonly used as a quick, passive way to check a board that’s fresh off the production line. These aren’t the X-Rays like those of broken bones you’re (hopefully not too) used to seeing though, they’re Computed Tomography scans (CT scans, CAT scans), in effect just 3D X-Rays.

For electronics manufacturers and assemblers, CT scans are incredibly useful because they provide a non-destructive way to check for errors. For example, how do you know if that middle BGA pin is actually soldered correctly? You could run a functional test and make sure everything is working (at least, everything you check), but that takes time. The longer it takes to validate, the higher the manufacturing cost. In manager speak: “cost bad. Fast good.”

It’s also common to use a CT scan to create a full 3D model of a board. This makes it easy to check every little detail, especially the ones that are visually obscured by surface mount devices or critical signal paths that are buried under board layers.

Highlight of solder joints on small-outline integrated circuit (SOIC) to a PCB’s pads.

If you want to geek out on CT scans, you can learn more about the lab that did this scan or by wading into this unclassified research paper from Australia’s Cyber and Electronic Warfare Division.

But we know you really want more of this video, but better. And we’ve got the goods. For the chill folk among you, here’s a 55-minute version without all the CT scan info cluttering the screen. For those of you currently blasting eDM in your headphones, here’s a 30 second clip of it looping at ~5x speed. Eat your heart out:

Continue reading “This CT Scan Of A PCB Is The Accidental ASMR We Didn’t Know We Needed” →

Anatomy Of A Power Outage: Explaining The August Outage Affecting 5% Of Britain

September 7, 2019 by Jenny List 18 Comments

Without warning on an early August evening a significant proportion of the electricity grid in the UK went dark. It was still daylight so the disruption caused was not as large as it might have been, but it does highlight how we take a stable power grid for granted.

The story is a fascinating one of a 76-second chain of unexpected shutdown events in which individual systems reacted according to their programming, resulted in a partial grid load shedding — what we might refer to as a shutdown. [Mitch O’Neill] has provided an analysis of the official report which translates the timeline into easily accessible text.

It started with a lightning strike on a segment of the high-voltage National Grid, which triggered a transient surge and a consequent disconnect of about 500MW of small-scale generation such as solar farms. This in turn led to a large offshore wind farm deloading itself, and then a steam turbine at Little Barford power station. The grid responded by bringing emergency capacity online, presumably including the Dinorwig pumped-storage plant we visited back in 2017.

Perhaps the most interesting part followed is that the steam turbine was part of a combined cycle plant, processing the heat from a pair of gas turbine generators. As it came offline it caused the two gas turbines feeding it to experience high steam pressure, meaning that they too had to come offline. The grid had no further spare capacity at this point, and as its frequency dropped below a trigger point of 48.8 Hz an automatic deloading began, in effect a controlled shutdown of part of the grid to reduce load.

This is a hidden world that few outside the high-power generation and transmission industries will ever see, so it’s very much worth a read. It’s something we’ve touched on before with the South American grid shutdown back in June, and for entirely different reasons in 2018 when an international disagreement caused the entire European grid to slow down.

Header image: Little Barford combined-cycle power station against the sunset. Tony Foster, (CC BY-SA 2.0).

Open Source Intel Helps Reveal US Spy Sat Capabilities

September 5, 2019 by Lewin Day 28 Comments

On the 30th August 2019, the President of the United States tweeted an image of an Iranian spaceport, making note of the recent failed Safir launch at the site. The release of such an image prompted raised eyebrows, given the high resolution of the image, and that it appeared to be a smartphone photo taken of a classified intelligence document.

Inquisitive minds quickly leapt on the photo, seeking to determine the source of the image. While some speculated that it may have been taken from a surveillance aircraft or drone, analysis by the satellite tracking community disagreed.

A comparison of the actual image, top, and a simulation of what a shot from USA 224 would look like. Ignore the shadows, which are from an image taken at a different time of day. Note the very similar orientation of the features of the launchpad.

The angle of shadows in the image was used to determine the approximate time that the image was taken. Additionally, through careful comparison with existing satellite images from Google Maps, it was possible to infer the azimuth and elevation of the camera. Positions of military satellites aren’t made public, but amateur tracking networks had data placing satellite USA 224 at a similar azimuth and elevation around the time the image was taken.

With both the timing and positioning pointing to USA 224, evidence seems conclusive that this KH-11 satellite was responsible for taking the image. The last confirmed public leak of a Keyhole surveillance image was in 1984, making this an especially rare occurrence. Such leaks are often frowned upon in the intelligence community, as nation states prefer to keep surveillance capabilities close to their chest. The Safir images suggest that USA 224 has a resolution of 10cm per pixel or better – information that could prove useful to other intelligence organisations.

It’s not the first time we’ve covered formerly classified information, either – this teardown of a Soviet missile seeker bore many secrets.

RISC-V Uses Carbon Nanotubes

August 31, 2019 by Al Williams 3 Comments

In a recent article in Nature, you can find the details of a RISC-V CPU built using carbon nanotubes. Of course, Nature is a pricey proposition, but you can probably find the paper by its DOI number if you bother to look for it. The researchers point out that silicon transistors are rapidly reaching a point of diminishing returns. However, Carbon Nanotube Field Effect Transistors (CNFETs) overcome many of these disadvantages.

The disadvantage is that the fabrication of CNFETs has been somewhat elusive. The tubes tend to clump and yields are low. The paper describes a method that allowed the fabrication of a CPU with over 14,000 transistors. A wafer gets nanotubes grown all over it and then some of them are removed. In addition, some design rules mitigate other problems.

In particular, a small percentage of the CNFETs will become metallic and have little to no bandgap. However, the DREAM design rules can increase the tolerance of the design to metallic CNFETs with no process changes.

Before you get too excited, limitations in channel length and contact size keep the processor running at a blazing 10 kHz. To paraphrase Weird Al, your operating system boots in a day and a half. The density isn’t great either since working around stray and metallic CNFETs means each transistor has multiple nanotubes in use.

On the other hand, it works. New technology doesn’t always match old technology at first, but you have to crawl before you walk, and walk before you run.

We imagine you won’t be able to buy this for $8 any time soon even if you wanted to. At 10 kHz, it probably isn’t going to make much of a desktop PC anyway.

A Radio Transceiver From A Cable Modem Chipset

August 31, 2019 by Jenny List 11 Comments

It’s a staple of our community’s work, to make electronic devices do things their manufacturers never intended for them. Analogue synthesisers using CMOS logic chips for example, or microcontrollers that bitbang Ethernet packets without MAC hardware. One of the most fascinating corners of this field comes in the form of software defined radios (SDRs), with few of us not owning an RTL2832-based digital TV receiver repurposed as an SDR receiver.

The RTL SDR is not the only such example though, for there is an entire class of cable modem chipsets that contain the essential SDR building blocks. The Hermes-Lite is an HF amateur radio transceiver project that uses an AD9866 cable modem chip as the signal end for its 12-bit SDR transceiver hardware with an FPGA between it and an Ethernet interface. It covers frequencies from 0 to 38.4 MHz, has 384 kHz of bandwidth, and can muster up 5W of output power.

It’s a project that’s been on our radar for the past few years, though somewhat surprisingly this is the first mention of it here on Hackaday. Creator [Steve Haynal] has reminded us that version 2 is now a mature project on its 9th iteration, and says that over 100 “Hermes-Lite 2.0” units have been assembled to date. If you’d like a Hermes-Lite of your own it’s entirely open-source, and they organise group buys of the required components.

Of course, SDRs made from unexpected components don’t have to be exotic.