Day: May 7, 2019

Supercapacitors Propel Rocket To The Skies

May 7, 2019 by 33 Comments

OK, so this isn’t really a rocket. In the strictest definition, rockets are vehicles or projectiles that propel themselves through jettisoning mass, usually through the combustion of fuel. But with electric motors getting stronger and stronger, folks are building craft that look a lot more like rockets than airplanes. [Tom Stanton] is one such person (Youtube link, embedded below).

We’ve seen “electric rocket” builds before, but where others have used lithium batteries, [Tom] has used supercapacitors instead. Six supercaps are installed in a 3D printed mount, and supply power to a 500 W brushless outrunner motor which gives the rocket the thrust to climb into the sky.

In testing, [Tom] estimates the rocket was able to reach an altitude of approximately 60 m, or 200 ft. That’s not particularly astounding, but it does prove that supercaps can run a high current load in a real world situation. Additionally, their fast recharge rate allows [Tom] to make a repeat flights in just about the time it takes to repack the parachute. Video after the break.

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How Art Became Science In Machining

May 7, 2019 by 57 Comments

Machining is one of those fascinating fields that bridges the pre-scientific and scientific eras. As such, it has gone from a discipline full of home-spun acquired wisdom and crusty old superstitions to one of rigorously analyzed physics and crusty old superstitions.

The earliest machinists figured out most of what you need to know just by jamming a tool bit into spinning stock and seeing what happens. Change a few things, and see what happens next. There is a kind of informal experimentation taking place here. People are gradually controlling for variables and getting better at the craft as they learn what seems to affect what. However, the difference between fumbling around and actually knowing something is controlling for one’s own biases in a reproducible and falsifiable way. It’s the only way to know for sure what is true, and we call this “science”. It also means being willing to let go of ideas you had because the double-blinded evidence clearly says they are wrong.

That last part is where human nature lets us down the most. We really want to believe things that confirm our preconceived notions about the world, justify our emotions, or make us feel better. The funny thing about science, though, is that it doesn’t care whether you believe in it or not. So go get your kids vaccinated, and up your machining game with scientific precision. Let’s take a look.

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Lots Of Blinky! ESP32 Drives 20,000 WS2812 LEDs

May 7, 2019 by 17 Comments

20,000 LEDs sounds like an amazing amount of blink. When we start to consider the process of putting together 20,000 of anything, and then controlling them all with a small piece of electronics the size of a postage stamp, we get a little bit dizzy. Continue reading “Lots Of Blinky! ESP32 Drives 20,000 WS2812 LEDs” →

Add USB-C To Your Laptop (Almost)

May 7, 2019 by 24 Comments

It’s a very brave person who takes a Dremel or similar to the case of their svelte new laptop in the quest for a new connector, it sounds as foolhardy as that hoax from a while back in which people tried to drill a 3.5mm jack into their new iPhones. But that’s what [BogdanTheGeek] has done, in adding a USB-C port to his Acer.

Of course, the port in question isn’t a fully functioning USB-C one, it’s a power supply jack, and it replaces the extremely unreliable barrel jack the machine was shipped with. He’s incorporated one of those little “ZYPDS” USB-C power delivery modules we’ve no-doubt all seen in the usual cheap electronic sources, and in a move of breathtaking audacity he’s cut away part of the Acer mainboard  to do so. He’s relying on the laptop’s ability to accept a range of voltages, and presumably trusting his steady hand with a rotary tool. Some Kapton tape and a bit of wire completes the work, and with a carefully reshaped hole in the outer case he’s good to go.

The result is beautifully done, and a casual observer would be hard pressed to know that it hadn’t always been a USB-C port. We’re sure there will come a moment at which someone will plug in a USB-C peripheral and expect it to work, it’s that good.

If you’d like to know a little bit more about USB-C, we’d like to direct you to our in-depth look at the subject.