Open Hardware Board For Robust USB Power Monitoring

December 11, 2018 by 9 Comments

We’ve all seen the little USB power meters that have become popular since nearly every portable device has adopted some variation of USB for charging. Placed between the power source and the device under test, they allow you to see voltage and current in real time. Perfect for determining how long you’ll be able to run a USB powered device on batteries, or finding out if a USB power supply has enough current to do the business.

[Jonas Persson] liked the idea of these cheap little gadgets, but wanted something a bit more scientific. His design, which he refers to as UPM, is essentially a “smart” version of those ubiquitous USB gadgets. Instead of just showing the data on a little LCD screen, it can now be viewed on the computer and analyzed. His little gadget even allows you to cut power to the device under test, potentially allowing for automated testing of things such as inrush current.

Essentially the UPM works in much the same way as the simple USB meters: one side of the device goes towards the upstream power source, and the device under test plugs into the other side. Between the two devices is a 16 bit ADC and differential amplifier which measures the voltage and current. There’s a header on the board which connects to the ADC if you wanted to connect the UPM to an external microcontroller or other data logging device.

But most likely you would be using the internal microcontroller to analyze the output of the ADC over I2C, which [Jonas] very cleverly connected to the upstream port with an integrated USB hub. One side of the hub goes off to the device being tested, and the other to the microcontroller. So the host device will see both the UPM’s integrated microcontroller and the target device at the same time. From there, you can use the ncurses user interface to monitor and control the device in real-time.

While the hardware looks more or less finished, [Jonas] has some more plans for the software side of UPM, including support for remote control and monitoring over TCP/IP as well as robust logging capabilities. This is definitely a very interesting project, and we’re excited to see it develop further.

In the past we’ve seen homebrew USB power meter builds, and even commercial offerings which boasted computer-based logging and analysis, so it was only a matter of time before somebody combined them into one.

Modified F Clamp Is Wheely Good

December 11, 2018 by 18 Comments

Sometimes, a job is heavy, messy, or unwieldy, and having an extra pair of hands to help out makes the job more than twice as easy. However, help isn’t always easy to find. Faced with this problem, [create] came up with an ingenious solution to help move long and heavy objects without outside assistance.

Simple, and effective.

The build starts with a regular F-clamp  – a familiar tool to the home woodworker. The clamp is old and worn, making it the perfect candidate for some experimentation. First off, the handle is given a good sanding to avoid the likelihood of painful splinters. Then, the top bar is drilled and tapped, and some threaded rod fitted to act as an axle. A polyurethane wheel from a children’s scooter is then fitted, and held in place with a dome nut.

The final product is a wheel that can be clamped to just about anything, making it easier to move. [create] demonstrates using the wheelclamp to move a long piece of lumber, but we fully expect to see these on the shelf of Home Depot in 12 months for moving furniture around the house. With a few modifications to avoid marring furniture, these clamps could be a removalist’s dream.

While you’re busy hacking your tools, check out these useful bar clamps, too. Video after the break.

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Julius Lilienfeld And The First Transistor

December 11, 2018 by 31 Comments

Here’s a fun exercise: take a list of the 20th century’s inventions and innovations in electronics, communications, and computing. Make sure you include everything, especially the stuff we take for granted. Now, cross off everything that can’t trace its roots back to the AT&T Corporation’s research arm, the Bell Laboratories. We’d wager heavily that the list would still contain almost everything that built the electronics age: microwave communications, data networks, cellular telephone, solar cells, Unix, and, of course, the transistor.

But is that last one really true? We all know the story of Bardeen, Brattain, and Shockley, the brilliant team laboring through a blizzard in 1947 to breathe life into a scrap of germanium and wires, finally unleashing the transistor upon the world for Christmas, a gift to usher us into the age of solid state electronics. It’s not so simple, though. The quest for a replacement for the vacuum tube for switching and amplification goes back to the lab of  Julius Lilienfeld, the man who conceived the first field-effect transistor in the mid-1920s.

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Off Road Vehicle Has Six Wheels And Fluid Power

December 11, 2018 by 44 Comments

What has six wheels and runs on water? Azaris — a new off-road vehicle prototype from Ferox. Azaris has a rocker suspension modeled after the one on the Mars rover. The problem is, linking four drive wheels on a rocker suspension would be a nightmare. The usual solution? Motors directly in the wheels. But Ferrox has a different approach.

The vehicle has a conventional BMW motorcycle engine but instead of driving a wheel, it drives a pump. The pump moves fluid to the wheels where something similar to a water wheel around the diameter of the wheel causes rotation. The fluid is mostly water and the pressure is lower than a conventional hydraulic system. Auto Times has a video of some stills of the prototype and you can see it below. We haven’t actually seen it in motion, unfortunately.

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ABS: Three Plastics In One

December 11, 2018 by 31 Comments

It would be really hard to go through a typical day in the developed world without running across something made from ABS plastic. It’s literally all over the place, from toothbrush handles to refrigerator interiors to car dashboards to computer keyboards. Many houses are plumbed with pipes extruded from ABS, and it lives in rolls next to millions of 3D-printers, loved and hated by those who use and misuse it. And in the form of LEGO bricks, it lurks on carpets in the dark rooms of children around the world, ready to puncture the bare feet of their parents.

ABS is so ubiquitous that it makes sense to take a look at this material in terms of its chemistry and its properties. As we’ll see, ABS isn’t just a single plastic, but a mixture that takes the best properties of its components to create one of the most versatile plastics in the world.

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True Transparent Parts From A Desktop 3D Printer

December 11, 2018 by 14 Comments

We’re no strangers to seeing translucent 3D printed parts: if you print in a clear filament with thin enough walls you can sorta see through the resulting parts. It’s not perfect, but if you’re trying to make a lamp shade or decorative object, it’s good enough. You certainly couldn’t print anything practical like viewing windows or lenses, leaving “clear” 3D printing as more of a novelty than a practical process.

But after months of refining his process, [Tomer Glick] has finally put together his guide for creating transparent prints on a standard desktop FDM machine. It doesn’t even require any special filament, he says it will work on PLA, ABS, or PETG, though for the purposes of this demonstration he’s using the new Prusament ABS. The process requires some specific print settings and some post processing, but the results he’s achieved are well worth jumping though a few hoops.

According to [Tomer] the secret is in the print settings. Essentially, you want the printer to push the layers together far closer than normal, in combination with using a high hotend temperature and 100% infill. The end result (hopefully) is the plastic being laid down by the printer is completely fused with the preceding one, making a print that is more of a literal solid object than we’re used to seeing with FDM printing. In fact, you could argue these settings generate internal structures that are nearly the polar opposite of what you’d see on a normal print.

The downside with these unusual print settings is that the outside of the print is exceptionally rough and ugly (as you might expect when forcing as much plastic together as possible). To expose the clear internals, you’ll need to knock the outsides down with some fairly intense sanding. [Tomer] says he starts with 600 and works his way up to 4000, and even mentions that when you get up to the real high grits you might as well use a piece of cardboard to sand the print because that’s about how rough the sandpaper would be anyway.

[Tomer] goes on to demonstrate a printed laser lens, and even shows how you can recreate the effect of laser-engraved acrylic by intentionally putting voids inside the print in whatever shape you like. It’s a really awesome effect and honestly something we would never have believed came off a standard desktop 3D printer.

In the past we’ve seen specialized filament deliver some fairly translucent parts, but those results still weren’t as good as what [Tomer] is getting with standard filament. We’re very interested in seeing more of this process, and are excited to see what kind of applications hackers can come up with.

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Biology Lab On Your Christmas List

December 11, 2018 by 6 Comments

We hope you have been good this year because we have a list to start your own biology lab and not everything will fit into Santa’s bag (of holding). If you need some last minute goodie points, Santa loves open-source and people who share on our tip line. Our friends at [The Thought Emporium] have compiled a list of the necessary equipment for a biology lab. Chemistry labs-in-a-box have been the inspiration for many young chemists, but there are remarkable differences between a chemistry lab and a biology lab which are explained in the Youtube video linked above and embedded after the break.

If you are preparing to start a laboratory or wondering what to add to your fledging lab, this video is perfect. It comes from the perspective of a hacker not afraid to make tools like his heat block and incubator which should absolutely be built rather than purchased but certain things, like a centrifuge, should be purchased when the lab is mature. In the middle we have the autoclave where a used pressure cooker may do the trick or you may need a full-blown commercial model with lots of space and a high-pressure range.

Maybe this will take some of the mystique out of starting your own lab and help you understand what is happening with a gel dock or why a spectrophotometer is the bee’s knees. There are a handful of other tools not mentioned here so if this is resonating, it will be worth a watch.

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