Cheap Big Servo For Robot Arm

November 19, 2021 by 10 Comments

[Skyentific] is looking to push the hobbyist robotics state of the art. Motors and their gears, the actuators, are typically the most expensive part. For his build, he realised he needed big servos capable of delivering plenty of torque. Thus, he set about creating a 3D-printed design to get the job done on a budget. (Video, embedded below.)

Stepper motors are the order of the day here, chosen for their low cost compared to brushless solutions, particularly when taking control hardware into account. In this design, the stepper motor drives a sun gear as part of a bigger planetary gearbox with a high gear ratio. Cross-roller bearings are used to allow the servo to effectively handle both radial and axial loads. The servo as a whole is designed to fit neatly into the joints of the robot arm itself, and has external mounting points provisioned as such.

It’s a neat servo that somewhat apes those used on full-sized industrial designs, at least in the sense of being an integrated part of the joints of a robot arm. It also comes in at a relatively-cheap $32 based on the materials used by [Skyentific].

We’ve seen some related work from [Skyentific] before, too – like this interesting cable-driven joint. Video after the break.

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A Nintendo 64 console with modern hardware internals

N64 Mini PC Conversion Includes All The Trimmings

November 18, 2021 by 8 Comments

We’ve seen quite a few retro gaming consoles physically modded to house modern emulation hardware, but the NUC-64 by [RetroModder] stands out as one of the most impressive Nintendo 64 guttings that we’ve seen to date.

Observed from the front, the NUC-64 almost resembles a stock Nintendo console. The project’s name is printed across the vestigial cartridge slot, and two suspiciously modern wireless networking antennas can be seen poking out from the back. The console’s modifications are fully revealed when looking at it from the rear – gone is the power brick socket, which now houses the I/O for the replacement motherboard. A custom 3D printed I/O shield keeps everything looking neat and tidy.

Internally, the new hardware is no slouch. The Intel NUC is a small-form-factor PC, and this miniature battlestation sports an 1.6GHz Intel N3700 Pentium processor, 4GB of DDR3 RAM, WiFi/Bluetooth connectivity and an M.2 SSD. This hardware runs circles around the original Nintendo 64, and is more than capable of emulating games from that system.

Most total conversions would call it a day here, however [RetroModder] has taken it a step further by producing a custom PCB that neatly ties together the console’s front I/O. Most importantly, two Mayflash N64-to-USB converters means that your favorite 1990s games can be enjoyed with the original controllers. The original power LED and reset switch are present, as is the sliding power switch which retains its original purpose, thanks to a simple 555 circuit that sends the expected power-on and power-off signals to the motherboard with each slide of the power switch. Additionally, a system of 3D printed mounts and brackets keeps everything secure inside the case.

All the build details can be found here. The NUC-64 follows on from last month’s GamecubePC. The build quality and attention to detail makes this conversion rather special, and it’s clear that a lot of care and planning was taken to pull this off. Hopefully the original N64 hardware can be repurposed as well, perhaps as a new portable console?

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There Were Almost Jet Packs On The Moon

November 18, 2021 by 21 Comments

Here it is almost 2022 and we still don’t have our jet packs. But don’t feel bad. NASA astronauts wanted a lunar jetpack, but they didn’t get one either. [Amy] at The Vintage Space has an interesting video about what almost was, and you can see it below.

Of course, a jet pack on the moon would be easier than an Earthbound one. The goal was to allow the crew to range further from their lander since they couldn’t carry very much and the lander didn’t have a lot of consumables, either. In addition, if you lost sight of the lander, getting back could be a problem since navigating on the moon was an unknown skill.

In 1969 awarded exploratory contracts for lunar personal flying vehicles including one to Bell who had their Earth-bound jet pack that shows up every so often for example in Bond movies.

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Isolated Oscilloscope Design Process Shows How It’s Done

November 18, 2021 by 31 Comments

[Bart Schroder] was busy designing high voltage variable speed motor drives and was lamenting the inability of a standard scope to visualise the waveforms around the switch transistors. This is due to the three phase nature of such motors being driven with three current waveforms, out of phase with each other by 120 degrees, where current flows between each pair of winding taps, without being referenced to a common notion of ground. The average scope on your bench however, definitely is ground-referenced, so visualising such waveforms is a bit of a faff. Then there’s the fact that the motors run at many hundreds of volts, and the prospect of probing that with your precious bench instrument is a little nerve-wracking to say the least. The solution to the issue was obvious, build your own isolated high voltage oscilloscope, and here is the Cleverscope CS448 development journey for your viewing pleasure.

The scope itself is specification-wise nothing too flash, it’s the isolated channels that make it special. It does however have some niceties such as an extra eight 100 Mbps digital inputs and a handy 65 MHz signal generator. Also, don’t reach for your wallets just yet, as this is a specialised instrument with an even smaller potential user base than a normal scope, so these units are rather pricey. That all said, it’s not the existence of the scope that is the focus here, it’s the journey from problem to solution that interests us the most. There is much to learn from [Bart’s] journey, for example, where to place the frontend ADC? Isolated side or not? The noise floor of the signal chain dictated the former.

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Minty Tunes Is Wireless Audio In An Altoids Tin

November 18, 2021 by 15 Comments

These days, a lot of phones don’t have audio jacks anymore. It can make it hard to listen to music if your favorite headphones aren’t already wireless-enabled. Minty Tunes solves that problem, combined with a little Altoids tin flair.

Yes, the long and the short of it is that this is a Bluetooth audio receiver built into a tin of mints. The build is relatively simple, hooking up a cheap Bluetooth audio decoder module to a lithium-polymer battery. This is paired with a TP4056 battery charger IC to allow the battery to be topped off easily. It’s all then wired up and stuck in everyone’s favorite hacker electronics enclosure.

For those who aren’t fans of wireless earbuds like AirPods and the like, it’s a useful solution for listening to music from a smartphone. As the builder notes, it’s also a great way to play music over a hi-fi or car stereo with an aux port. Alternatively, you could always build your own pocket MP3 player from scratch. Video after the break.

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Light projected through prisms on to laser-cut letters submerged in water.

YOU Are A Projection Of Your Influences

November 18, 2021 by 5 Comments

Who are you? No, who are you really? You’re an amalgamation of influences from your family, your friends, the media, and the parasocial relationships you have with fictional characters. It’s okay; we all are. It can’t be helped that there’s a lot of it about.

[Kim Pimmel]’s YOU examines this question of identity in the form of  projected typography. YOU are solidly laser-cut at birth, but then come the influences — the water of everyday life that surrounds you, the lights that mask your dread or lay you bare, and the prisms of circumstance that twist the light into brilliant patterns that burn memories into your brain.

In this case, the light comes from a hacked camping headlamp that was past its prime. [Kim] laser-cut the letters from acrylic and submerged them in water, which can be manipulated to enhance the effect and mimic the turmoil of life. For added effect, [Kim] held prisms in the light’s path to refract it and cause the patterns to dance. Be sure to check it out after the break, and don’t forget to turn on the sound so you can hear [Kim]’s original composition.

Want to see more trippy typography? Check out this vector art that started as Perlin noise.

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Privacy Report: What Android Does In The Background

November 18, 2021 by 76 Comments

We’ve come a long way from the Internet of the 90s and early 00s. Not just in terms of technology, capabilities, and culture, but in the attitude most of us take when accessing the ‘net. In those early days most users had a militant drive to keep any personal or identifying information to themselves beyond the occasional (and often completely fictional) a/s/l, and before eBay and Amazon normalized online shopping it was unheard of to even type in a credit card number. On today’s internet we do all of these things with reckless abandon, and to make matters worse most of us carry around a device which not only holds all of our personal information but also reports everything about us, from our browsing habits to our locations, back to databases to be stored indefinitely.

It was always known that both popular mobile operating systems for these devices, iOS and Android, “phone home” or report data about us back to various servers. But just how much the operating systems themselves did was largely a matter of speculation, especially for Apple devices which are doing things that only Apple can really know for sure. While Apple keeps their mysteries to themselves and thus can’t be fully trusted, Android is much more open which paradoxically makes it easier for companies (and malicious users) to spy on users but also makes it easier for those users to secure their privacy on their own. Thanks to this recent privacy report on several different flavors of Android (PDF warning) we know a little bit more on specifically what the system apps are doing, what information they’re gathering and where they’re sending it, and exactly which versions of Android are best for those of us who take privacy seriously.

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