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Wind Power Is Taking Off In China– All The Way to 2000 m AGL

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2000 m above ground level (AGL), winds are stronger and much, much more consistent than they are at surface. Even if the Earth were a perfect sphere, there’d be a sluggish boundry layer at the surface, but since it’s got all these interesting bumps and bits and bobs, it’s not just sluggish but horribly turbulent, too. Getting above that, as much as possible, is why wind turbines are on big towers. Rather than build really big tower, Beijing Lanyi Yunchuan Energy Technology Co. has gone for a more ambitious approach: an aerostat to take power from the steady winds found at high altitude. Ambitiously called the Stratosphere Airborne Wind Energy System (SAWES) , the megawatt-scale prototype has recently begun feeding into the grid in Yibin, Sichuan Province. The name might be a bit ambitious, since its 2000 m test flight is only one tenth of the way to the stratosphere, but Yibin isn’t a bad choice for testing: as it is well inland, the S2000 prototype won’t have to contend with typhoon...
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Robot Looks Exactly Like a Roll of Filament, If Filament Had Eyes

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[Matt Denton]’s SpoolBot is a surprisingly agile remote-controlled robot that doesn’t just repurpose filament spool leftovers. It looks exactly like a 2 kg spool of filament; that’s real filament wound around the outside of the drum. In fact, Spoolie the SpoolBot looks so much like the real thing that [Matt] designed a googly-eye add-on, because the robot is so easily misplaced. The robot’s mass rotates around a central hub in order to move forward or back. SpoolBot works by rotating its mass around the central hub, which causes it to roll forward or back. Steering is accomplished by tank-style turning of the independent spool ends. While conceptually simple, quite a bit of work is necessary to ensure SpoolBot rolls true, and doesn’t loop itself around inside the shell during maneuvers. Doing that means sensors, and software work. To that end, a couple of rotary encoders complement the gearmotors and an IMU takes care of overall positional sensing while an ESP32 runs the show. ...
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Driving WS2812Bs With Pure Logic

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The WS2812B has become one of the most popular addressable LEDs out there. They’re easy to drive from just about any microcontroller you can think of. But what if you have a microcontroller at all? [Povilas Dumcius] decided to try and drive the LEDs with raw logic only. The project consists of a small board full of old-school ICs that can be used to drive WS2812Bs in a simplistic manner. A 74HC14 Schmitt trigger oscillator provides the necessary beat for this tune, generating an 800 kHz clock to keep everything in time and provide the longer pulse trains that represent logic one to a WS2812B. A phase-shifted AND gate generates the shorter pulses necessary to indicate logic zero. Meanwhile, a binary counter cycles through 24 bits (8 per R, G, and B) to handle color. Pressing each one of the three pushbuttons allows each color channel to be activated or deactivated as desired. It can make the strip red, green, or blue, or combine the channels if you press multiple buttons at once. That...
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Building the Haxocorder

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The Haxophone is an open source MIDI saxophone project that has achieved some popularity. It’s caught the attention of [Shieladixon] not because she is a saxophonist but because she plays the recorder and is dissatisfied with existing MIDI recorder peripherals. She’s set about modifying the device to produce the Haxocorder, a better MIDI recorder . The video below the break is the third of a series, of which part one and part two deal with the Haxophone and the shortcomings of her existing recorder peripheral. She’s replacing the Pi Zero of the Haxophone with a Pi Pico in a Zero form factor, and simplifying its design significantly to remove unnecessary features. The result is a versatile instrument capable at a touch of becoming the full range of recorders, which she demonstrates with some nifty duet work. The upstream Haxophone project can be found here if you are interested, and we hope she follows this up with a release of her mods to make the Haxocorder. Meanwhile if you fee...
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Adding a Panadapter to a Classic Receiver

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There was a time when only the richest ham radio operators could have a radio with a panadapter. Back in the day, this was basically a spectrum analyzer that monitored a broad slice of the receiver’s intermediate frequency so you could see signals on either side of the receiver’s actual frequency. Today, with SDR technology and computers, this is an easy thing for receivers to implement. But what if you want to refit a classic radio? It isn’t that hard, and [Mirko Pavleski] shares his notes on how he tackled the project . You can also check it out in the video below. The plan is simple. A FET amplifier taps the radio’s IF stage before the first IF filter. This provides good isolation and buffering. Then, an emitter follower stage provides a matched output to the SDR through a low-pass filter. The SDR remains tuned to the IF frequency, of course. The rest is essentially software and procedures. Of course, your exact connection to your radio will differ unless you have the same recei...
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Random Number Generator Uses Camera Noise

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Random numbers are very important to us in this computer age, being used for all sorts of security and cryptographic tasks. [Theory to Thing] recently built a device to generate random numbers using nothing more complicated than simple camera noise. The heart of the build is an ESP32 microcontroller, which [Theory to Thing] first paired with a temperature sensor as a source of randomness. However, it was quickly obvious that a thermocouple in a cup of tea wasn’t going to produce nice, jittery, noisy data that would make for good random numbers. Then, inspiration struck, when looking at vision from a camera with the lens cap on. Particularly at higher temperatures, speckles of noise were visible in the blackness—thermal noise, which was just what the doctor ordered. Thus, the ESP32 was instead hooked up to an OV3660 camera, which was then covered up with a piece of black electrical tape. By looking at the least significant bits of the pixels in the image, it was possible to pick up ...
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Stop Ironing 3D Prints

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If you want smooth top surfaces on your 3D printed parts, a common technique is to turn on ironing in your slicer. This causes the head to drag through the top of the part, emitting a small amount of plastic to smooth the surface. [Make Wonderful Things] asserts that you don’t need to do this time-consuming step. Instead, he proposes using statistical analysis to identify the optimal settings to place the top layer correctly the first time , as shown in the video below. The parameters he thinks make a difference are line width, flow ratio, and print speed. Picking reasonable step sizes suggested that there were 19,200 combinations of settings to test. Obviously, that’s too many, so he picked up techniques from famous mathematician [George E. P. Box] and also used Bayesian analysis to reduce the amount of printing required to converge on the perfect settings. Did it work? Judging from the video, it appears to have done so. The best test pieces looked as good as the one that used trad...
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