Space Garbage Truck Passes Its First Test

September 20, 2018 by 54 Comments

Back in April we reported on the successful launch of the SpaceX Falcon 9 rocket to the International Space Station which carried, along with supplies and experiments for the orbiting outpost, the RemoveDEBRIS spacecraft. Developed by the University of Surrey, RemoveDEBRIS was designed as the world’s first practical demonstration of what’s known as Active Debris Removal (ADR) technology. It included not only a number of different technologies for ensnaring nearby objects, it even brought along deployable targets to use them on.

Orbital debris (often referred to simply as “space junk”) is a serious threat to all space-faring nations, and has become even more pressing of a concern as the cost of orbital launches have dropped precipitously over the last few years, accelerating number and frequency of new objects entering orbit. The results of these first of their kind tests have therefore been hotly anticipated, as the technology to actively remove debris from Low Earth orbit (LEO) is seen by many in the industry to be a key element of expanding access to space for commercial purposes.

Six months after its arrival in space we’ve now starting to see the first results of the groundbreaking tests performed by the RemoveDEBRIS spacecraft, and so far it’s very promising.

Continue reading “Space Garbage Truck Passes Its First Test” →

Show That Sega Saturn Save Battery Who’s Boss

September 20, 2018 by 26 Comments

Breaking out the Sega Saturn out of the closet for a hit of 90’s nostalgia comes with its own set of compromises: the wired controllers, the composite video, and worst of all that dead CR2032 battery behind the backdoor. Along with the death of that battery went your clock and all those precious hours put into your game save files. While the bulk of us kept feeding the insatiable SRAM, a friendly Canadian engineer named [René] decided to fix the problem for good with FRAM.

The issue with the battery-backed memory in the Saturn stems from the particularly power-hungry factory installed SRAM chip. Normally when the console is plugged-in to a main power source the CR2032 battery is not in use, though after several weeks in storage the battery slowly discharges. [René’s] proposed solution was to use a non-volatile form of RAM chip that would match the pinout of the factory SRAM as close as possible. This would allow for easier install with the minimum number of jumper wires.

Enter the FM1808 FRAM chip complete with a whopping 256 kb of addressable memory. The ferroelectric chip operates at the same voltage as the Saturn’s factory SRAM, and has the added benefit of being able to use a read/write mode similar to that of the Saturn’s original memory chip. Both chips conform to a DIP-28 footprint, and only a single jumper wire on pin 22 was required to hold the FM1808 chip’s output-enable signal active-low as opposed to the active-high enable signal on the Saturn’s factory memory chip. The before and after motherboard photos are below:

After a quick test run of multiple successful read and writes to memory, [René] unplugged his Saturn for a couple days and found that his save files had been maintained. According to the FM1808 datasheet, they should be there for the next 45 years or so. The only downside to the upgrade is that the clock & calendar settings were not maintained upon boot-up and reset to the year 1996. But that’s nothing a bit of button-mashing through couldn’t solve, because after all wasn’t the point of all this to relive a piece of the 90s?

For more Sega Saturn goodness, check out how the Sega Saturn was finally cracked after 20 years.

Learn ARM Assembly With The Raspberry Pi

September 20, 2018 by 41 Comments

We live in a time when you don’t have to know assembly language to successfully work with embedded computers. The typical processor these days has resources that would shame early PCs and some of the larger ones are getting close to what was a powerful desktop machine only a few years ago. Even so, there are some cases where you really want to use assembly language. Maybe you need more speed. Or maybe you need very precise control over timing. Maybe you just like the challenge. [Robert G. Plantz] from Sonoma State University has an excellent book online titled “Introduction to Computer Organization: ARM Assembly Langauge Using the Raspberry Pi.” If you are interested in serious ARM assembly language, you really need to check out this book.

If you are more interested in x86-64 assembly and Linux [Plantz] has you covered there, too. Both books are free to read on the Internet, and you can pick up a printed version of the Linux book for a small payment if you want.

Continue reading “Learn ARM Assembly With The Raspberry Pi” →

Touch Anything And Everything

September 19, 2018 by 10 Comments

Powering IoT devices is often a question of batteries or mains power, but in rare exceptions to this rule there is no power supply (PDF Warning). At the University of Wisconsin-Madison and the University of California, San Diego, researchers have gone the extra mile to make advanced backscatter devices, and these new tags don’t need the discrete components we have seen in previous versions. They are calling it LiveTag, and it doesn’t need anything aside from a layer of foil printed or etched on a flexible ceramic-PTFE laminate. PTFE is mostly seen in the RF sector as a substrate for circuit boards.

We have seen some of the wild creations with wifi backscatter that range from dials to pushbuttons. RF backscatter works by modulating the RF signals in which we are continuously swimming. Those radio waves power the device and disrupt the ambient signals, which disruption can be detected by a receiver. With a BOM that looks like a statement more than a list, integration with many devices becomes a cost-effective reality. Do not however broadcast important data because you cannot expect great security from backscatter.

[Via IEEE Spectrum]

Advanced Techniques For Using Git With KiCAD

September 19, 2018 by 4 Comments

For most developers “distributed version control” probably means git. But by itself git doesn’t work very well with binary files such as images, zip files and the like because git doesn’t know how to make sense of the structure of an arbitrary blobs of bytes. So when trying to figure out how to track changes in design files created by most EDA tools git doesn’t get the nod and designers can be trapped in SVN hell. It turns out though KiCAD’s design files may not have obvious extensions like .txt, they are fundamentally text files (you might know that if you’ve ever tried to work around some of KiCAD’s limitations). And with a few tweaks from [jean-noël]’s guide you’ll be diffing and merging your .pro’s and .sch’s with aplomb.

There are a couple sections to the document (which is really meant as an on boarding to another tool, which we’ve gotten to in another post). The first chunk describes which files should be tracked by the repo and which the .gitignore can be configured to avoid. If that didn’t make any sense it’s worth the time learning how to keep a clean repo with the magic .gitignore file, which git will look for to see if there are any file types or paths it should avoid staging.

The second section describes how you can use two nifty git features, cleaning and smudging, to dynamically modify files as they are checked in and out of the repo. [jean-noël]’s observation is that certain files get touched by KiCAD even if there are no user facing changes, which can clutter patch sets with irrelevant changes. His suggested filters prevent this by stripping those changes out as files get checked in. Pretty slick.

Electric Wheelbarrow Makes Hauling Big Loads Easier

September 19, 2018 by 20 Comments

Gardening involves a depressing amount of physical activity: haul this over here, dump it there and then cover it with this. Things like wheelbarrows are still damn hard work, especially for people like who are somewhat physically compromised. That’s why we love this build from [Karl Gesslein]. He usually makes electronic bikes, adding motors to bicycles to roam the streets faster. But this time he applied his expertise to a wheelbarrow. He added a 3000W motor to the wheelbarrow, which drives the front wheel when triggered by the accelerator on the handle.

Continue reading “Electric Wheelbarrow Makes Hauling Big Loads Easier” →

Voice Controlled Stereo Balance With ESP8266

September 19, 2018 by 13 Comments

A stereo setup assumes that the listener is physically located between the speakers, that’s how it can deliver sound equally from both sides. It’s also why the receiver has a “Balance” adjustment, so the listener can virtually move the center point of the audio by changing the relative volume of the speakers. You should set your speaker balance so that your normal sitting location is centered, but of course you might not always be in that same position every time you listen to music or watch something.

[Vije Miller] writes in with his unique solution to the problem of the roving listener. He’s come up with a system that can adjust the volume of his speakers without having to touch the receiver’s setup, in fact, he doesn’t have to touch anything. By leveraging configurable voice control software running on his computer, his little ESP8266-based devices do all the work.

Each speaker has its own device which consists of a NodeMCU ESP8266 and X9C104 digital potentiometer inside of a 3D printed case. The audio terminal block on the gadget allows him to connect it inline between the speaker and the receiver, giving [Vije] the ability to adjust the volume through software. The source code, which he’s posted on the Hackaday.io project page, uses a very simple REST-style API to change speaker volume based on HTTP requests which hit the ESP8266’s IP address.

The second part of the project is a computer running VoiceAttack, which lets [Vije] assign different actions based on what the software hears. When he says the appropriate command, the software goes through and fires off HTTP requests to the nodes in the system. Everything is currently setup for two speakers, but it shouldn’t be too difficult to expand to more speakers (or even rooms) with some adjustment to the software.

It’s not the first voice controlled speaker we’ve ever seen, but it does solve a very specific problem in a unique way. We’d be interested in seeing the next logical step, which would see this technology integrated into the speaker itself.

Continue reading “Voice Controlled Stereo Balance With ESP8266” →