Robot Arm Gives Kids The Roller Coaster Ride Of Their Lives

Unfortunately, [Dave Niewinski]’s kids are still too little to go on a real roller coaster. But they’re certainly big enough to be tossed around by this giant robot arm roller coaster simulator.

As to the question of why [Dave] has a Kuka KR 150 robot in his house, we prefer to leave that unasked and move forward. And apparently, this isn’t his first attempt at using the industrial robot as a motion simulator. That attempt revealed a few structural problems with the attachment between the rider’s chair and the robot’s wrist. After redesigning the frame with stouter metal and adding a small form-factor gaming PC and a curved monitor in front of the seat, [Dave] was ready to figure out how to make the arm simulate the motions of a roller coaster.

Now, if you ever thought the world would be a better place if only we had a roller coaster database complete with 4k 60 fps video captured from real coasters, you’re in luck. CoasterStats not only exists, but it also includes six-axis accelerometer data from real rides of coasters across Europe. That gave [Dave] the raw data he needed, but getting it translated into robot motions that simulate the feeling of the ride was a bit tricky. [Dave] goes into the physics of it all in the video below, but suffice it to say that the result is pretty cool.

More after the break.

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3D Printed Jet Engine Goes Turbo

Printing a model jet engine is quite an accomplishment. But it wasn’t enough for [linus3d]. He wanted to redesign it to have a turbojet, an afterburner, and a variable exhaust nozzle. You can see how it all goes together in the video below.

This took months of work and it shows. This probably won’t make a good rainy-day weekend project. You do need a few ball bearings and some M2 hardware, but it is mostly 3D printed.

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Be Your Own DJ With QN8066 And An Arduino Library

The QN8066 is a fun little FM transmitter chip. It covers the full FM broadcast band and has built-in DSP. You would find this sort of part in car cell phone adapters before every vehicle included Bluetooth or an AUX port.  [Ricardo] has created an Arduino library to bring the QN8066 to the masses.

The chip is rather easy to use – control is handled with a common I2C interface. All the complex parts – Phase Locked Loop (PLL), RF front end, power management, and audio processing are all hidden inside. [Ricardo’s] library makes it even easier to use. One of the awesome features of the 8066 is the fact that it handles Radio Data System (RDS). RDS is the subcarrier datastream that allows FM stations to inject information like song title and artist into the signal. The data is then displayed on your radio screen.

You can find the source to [Ricardo’s] library on GitHub. Using it is as simple as picking it up from the Arduino IDE.

If you are looking for an RDS-enabled radio to test out your QN8066 design, you wouldn’t do too bad with this Gameboy cartridge receiver.

Click through the break for a video from [Ricardo] explaining his QN8066 design. Continue reading “Be Your Own DJ With QN8066 And An Arduino Library”

Laser Fault Injection On The Cheap

One can only imagine the wonders held within the crypto labs of organizations like the CIA or NSA. Therein must be machines of such sophistication that no electronic device could resist their attempts to defeat whatever security is baked into their silicon. Machines such as these no doubt bear price tags that only a no-questions-asked budget could support, making their techniques firmly out of reach of even the most ambitious home gamer.

That might be changing, though, with this $500 DIY laser fault injection setup. It comes to us from Finnish cybersecurity group [Fraktal], who have started a series of blog posts detailing how they built their open-source reverse-engineering rig. LFI is similar to other “glitching” attacks we’ve covered before, such as EMP fault injection, except that a laser shining directly on a silicon die is used to disrupt its operation rather than a burst of electromagnetic energy.

Since LFI requires shining the laser very precisely on nanometer-scale elements of a bare silicon die, nanopositioning is the biggest challenge. Rather than moving the device under attack, the [Fraktal] rig uses a modified laser galvanometer to scan an IR laser over the device. The galvo and the optical components are all easily available online, and they’ve started a repo to document the modifications needed and the code to tire everything together.

Of course, this technique requires the die in the device under study to be exposed, but [Fraktal] has made that pretty approachable too. They include instructions for milling away the epoxy from the lead-frame side of a chip, which is safer for the delicate structures etched into the top of the die. The laser can then shine directly through the die from the bottom. For “flip-chip” packages like BGAs, the same milling technique would be done from the top of the package. Either way, we can imagine a small CNC mill making the process safer and quicker, even though they seem to have done pretty well with a Dremel.

This looks like a fantastic reverse engineering tool, and we’re really looking forward to the rest of the story.
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The Waveguide Explanation You Wish You’d Had At School

Anyone who has done an electronic engineering qualification will at some point have had to get to grips with transmission lines, and then if they are really lucky, waveguides. Perhaps there should be one of those immutable Laws stating that for each step in learning about these essential parts, the level of the maths you are expected to learn goes up in an exponential curve, for it’s certainly true that most of us breathe a hefty sigh of relief when that particular course ends. It’s not impossible to understand waveguides though, and [Old Hack EE] is here to slice through the formulae with some straightforward explanations.

First of all we learn about the basics of propagation in a waveguide, then we look at the effects of dimension on frequency. Again, there’s little in the way of head-hurting maths, just real-world explanations of cutt-off frequencies, and of coupling techniques. For the first time we’ve seen, here are simple and understandable explanations of the different types of splitter, followed up by the famous Magic T. It’s all in the phase, this is exactly the stuff we wish we’d had at university.

The world needs more of this type of explanation, after all it’s rare to watch a YouTube video and gain an understanding of something once badly taught. Take a look, the video is below the break.

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500cc Of 4-Wheel Off-Road Fun

Who among us hasn’t at some point thought of building a little vehicle, and better still, a little off-road vehicle for a few high-octane rough-terrain adventures. [Made in Poland] has, and there he is in a new video with a little off-road buggy.

The video which we’ve paced below the break is quite long, and it’s one of those restful metalworking films in which we see the finished project take shape bit by bit. In this case the buggy has a tubular spaceframe, with front suspension taken from a scrap quad and a home-made solid rear axle. For power there’s a 500cc Suzuki two-cylinder motorcycle engine, with a very short chain drive from its gearbox to that axle. The controls are conventional up to a point, though we’d have probably gone for motorcycle style handlebars with a foot shift rather than the hand-grip shift.

The final machine is a pocket drift monster, and one we’d certainly like to have a play with. We’d prefer some roll-over protection and we wonder whether the handling might be improved were the engine sprung rather than being part of a huge swing-arm, but it doesn’t appear to interfere with the fun. If you fancy a go yourself it’s surprisingly affordable to make a small vehicle, just build a Hacky Racer.

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Custom Pneumatic Cylinders Lock This Monitor Arm In Place

Few consumer-grade PCs are what you’d categorize as built to last. Most office-grade machines are as likely as not to give up the ghost after ingesting a few too many dust bunnies, and the average laptop can barely handle a few drops of latte and some muffin crumbs before croaking. Sticking a machine like that in the shop, especially a metal shop, is pretty much a death sentence.

And yet, computers are so useful in the shop that [Lucas] from “Cranktown City” built this neat industrial-strength monitor arm. His design will look familiar to anyone with a swing-arm mic or desk light, although his home-brew parallelogram arm is far sturdier thanks to the weight of the monitor and sheet-metal enclosure it supports. All that weight exceeded the ability of the springs [Lucas] had on hand, which led to the most interesting aspect of the build — a pair of pneumatic locks. These were turned from a scrap of aluminum rod and an old flange-head bolt; when air pressure is applied, the bolt is drawn into the cylinder, which locks the arm in place. To make it easy to unlock the arm, a pneumatic solenoid releases the pressure on the system at the touch of a button. The video below has a full explanation and demonstration.

While we love the idea, there are a few potential problems with the design. The first is that this isn’t a fail-safe design, since pressure is needed to keep the arm locked. That means if the air pressure drops the arm could unlock, letting gravity do a number on your nice monitor. Second is the more serious problem [Lucas] alluded to when he mentioned not wanting to be in the line of fire of those locks should something fail and the piston comes flying out under pressure. That could be fixed with a slight design change to retain the piston in the event of a catastrophic failure.

Problems aside, this was a great build, and we always love [Lucas]’ seat-of-the-pants engineering and his obvious gift for fabrication, of which his wall-mount plasma cutter is a perfect example.

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