Switching Regulators For Dummies

We often use linear regulators in our designs. They are cheap and simple – you put the regulator chip itself on the board, add two capacitors, and get a voltage. Linear regulators are imperfect, of course – they can’t help but waste the voltage difference as heat, for a start, which straight up excludes them for high-current purposes, or significant voltage difference conversions, unless you have a hefty heatsink handy. They also can’t boost voltage, which means you can only go from high to low – a bit of a disappointment.

Of course, we haven’t been just throwing our hands up in the air if a linear regulator doesn’t fit our purpose. Switching regulators have none of these disadvantages, which is why your mobile phone alone has a few dozen of these. They are way more efficient and hi-tec, able to convert one voltage into another while losing hardly any power into heat. All that you need to do is switch an inductor at a somewhat high frequency!

However, for some, switching regulators might look a bit intimidating. They tend to have higher standards for board layout compared to linear regulators, and, they do need an inductor – sometimes, a few more components too. Inductors alone are somewhat intimidating components, with a fair few more parameters than we’d expect, and you might get confused when looking into adding a switching regulator to your circuit.

No more! In this article, I shall give you the switching regulator basics, remove any fog of war that might be clouding your vision, and show you just how easily you can get a good few amps at your favourite voltage whenever you need it. Continue reading “Switching Regulators For Dummies”

3D Printed Screw Compressor Revisited

[Indeterminate Design] tried to 3D print a screw compressor some time ago but wasn’t satisfied with the result. He’s trying it again, and you can check it out in the video below. You can also download the 3D printable files.

This isn’t a 3D-printed keychain. The screw threads have to mesh with a small space between them, and the design is not trivial. Even if you don’t want to build your own, the look inside the engineering behind these devices is interesting, and there is quite a bit of background about how the rotor’s shapes are optimized.

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‘Radar’ Glasses Grant Vision-free Distance Sensing

[tpsully]’s Radar Glasses are designed as a way of sensing the world without the benefits of normal vision. They consist of a distance sensor on the front and a vibration motor mounted to the bridge for haptic feedback. The little motor vibrates in proportion to the sensor’s readings, providing hands-free and intuitive feedback to the wearer. Inspired in part by his own experiences with temporary blindness, [tpsully] prototyped the glasses from an accessibility perspective.

The sensor is a VL53L1X time-of-flight sensor, a LiDAR sensor that measures distances with the help of pulsed laser light. The glasses do not actually use RADAR (which is radio-based), but the operation is in a sense quite similar.

The VL53L1X has a maximum range of up to 4 meters (roughly 13 feet) in a relatively narrow field of view. A user therefore scans their surroundings by sweeping their head across a desired area, feeling the vibration intensity change in response, and allowing them to build up a sort of mental depth map of the immediate area. This physical scanning resembles RADAR antenna sweeps, and serves essentially the same purpose.

There are some other projects with similar ideas, such as the wrist-mounted digital white cane and the hip-mounted Walk-Bot which integrates multiple angles of sensing, but something about the glasses form factor seems attractively intuitive.

Thanks to [Daniel] for the tip, and remember that if you have something you’d like to let us know about, the tips line is where you can do that.

Sun On The Run: Diving Into Solar With A Mobile PV System

For obvious reasons, there has been a lot of interest in small-scale residential solar power systems lately. Even in my neck of the woods, where the sun doesn’t shine much from October to April, solar arrays are sprouting up on rooftops in a lot of local neighborhoods. And it’s not just here in suburbia; drive a little way out into the country or spend some time looking around in Google maps and it won’t take long to spy a sizable array of PV panels sitting in a field next to someone’s ranch house or barn.

Solar has gotten to the point where the expense of an installation is no longer a serious barrier to entry, at least if you’re willing to put in a little sweat equity and not farm the project out to a contractor. Doing it yourself requires some specialized tools and knowledge, though, over and above your standard suite of DIY skills. So, in the spirit of sharing hard-won knowledge, I decided to take the somewhat unusual step of writing up one of my personal projects, which has been in progress for a couple of years now and resulted in a solar power system that isn’t on a rooftop or a ground-mounted array at all, but rather is completely mobile: my solar trailer.

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Vroomba Gets Upgrades And A Spoiler

[Electrosync] is the creator and driver of the world’s fastest robotic vaccum cleaner, the Vroomba. It’s a heavily modified roomba capable of speeds of around 60 kph, well beyond the pedaling speed of most bicyclists. Despite being rejected by Guinness for a world record, we’re fairly confident that no other vacuum cleaners have gotten up to these speeds since the Vroomba first hit the streets. That’s not going to stop [electrosync] from trying to top his own record, though, and he’s brought the Vroomba some much needed upgrades.

The first, and perhaps most important, upgrades are to some of the structural components and wheels. The robot is much heavier than comparable RC vehicles and is under much greater strain than typical parts are meant to endure, so he’s 3D printed some parts of the chassis and some new wheels using a nylon-carbon fiber filament for improved strength. The wheels get a custom polyurethane coating similar to last time.

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Simulating A Time-Keeping Radio Signal

As far as timekeeping goes, there’s nothing more accurate and precise than an atomic clock. Unfortunately, we can’t all have blocks of cesium in our basements, so various agencies around the world have maintained radio stations which, combined with an on-site atomic clock, send out timekeeping signals over the air. In the United States, this is the WWVB station located in Colorado which is generally receivable anywhere in the US but can be hard to hear on the East Coast. That’s why [JonMackey], who lives in northern New Hampshire, built this WWVB simulator.

Normally, clocks built to synchronize with the WWVB station include a small radio antenna to receive the 60 kHz signal and the 1-bit-per-second data transmission which is then decoded and used to update the time shown on the clock. Most of these clocks have internal (but much less precise) timekeeping circuitry to keep themselves going if they lose this signal, but [JonMackey] can go several days without his clocks hearing it. To make up for that he built a small transmitter that generates the proper timekeeping code for his clocks. The system is based on an STM32 which receives its time from GPS and broadcasts it on the correct frequency so that these clocks can get updates.

The small radio transmitter is built using one of the pins on the STM32 using PWM to get its frequency exactly at 60 kHz, which then can have the data modulated onto it. The radiating area is much less than a meter, so this isn’t likely to upset any neighbors, NIST, or the FCC, and the clocks need to be right beside it to update. Part of the reason why range is so limited is that very low frequency (VLF) radios typically require enormous antennas to be useful, so if you want to listen to more than timekeeping standards you’ll need a little bit of gear.

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Hackaday Links: January 14, 2024

How long does it take a team of rocket scientists to remove two screws? When the screws they’re working on are keeping a priceless sample of asteroid safe, it’s about three months. That’s how long NASA has been working on the OSIRIS-REx sample return canister, which came back to Earth from asteroid Bennu back in September. The container was crammed full of asteroid bits, thanks in part to an overly energetic impact between the sample-collecting boom and Bennu. There was so much stuff that planetary scientists were able to recover about 70 grams of material that was covering the outside of the sealed container; this must have been a boon to the engineers, who got to figure out how to open the jammed cover of the container without anyone breathing down their necks for samples to study. The problem was a pair of stuck fasteners out of the 35 holding the lid on the container; the solution was far more complicated than a spritz of WD-40 and a little bit of heating with an oxy-acetylene torch. Engineers had to design two “clamp-like tools” and test them on a mock-up to make sure they wouldn’t contaminate the sample. We’d love to know more about these tools; trust us, we’ll be looking into this closely. If we find anything, a full article will be forthcoming.

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