Day: December 27, 2016

200 Years Of The Stirling Engine

December 27, 2016 by 56 Comments

In the early years of the nineteenth century, steam engines were at work in a variety of practical uses. However, they were still imperfect in many ways. One particular problem were the boilers, that had a tendency to explode, causing injuries and fatalities. Reverend Dr. Robert Stirling, a Scottish clergyman, was concerned about the death toll from exploding boilers. Based on previous work by George Cayley (known for his pioneering work on aeronautics), Stirling filed his patent for a safer engine in 1816. That makes this year the bicentenary of this engine. The Stirling engine has the highest theoretical efficiency of any thermal engine. It is also a relatively simple machine. Unlike other types of engines, there are no valves, and that makes the mechanical design much simpler.

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Long-range Electric Longboard Outlasts Rider

December 27, 2016 by 24 Comments

What could be better than a holiday ride past the palm trees and blue waters of a Mediterranean resort town? Perhaps making that ride on a long-range electric longboard of your own design will ice that particular cake.

And when we say long range, we mean it – an estimated 25 miles. The only reason [overclocker_kris] couldn’t come up with an exact number in the test drive seen below is that he got too tired to continue after mile 20. With a bit of juice left in the 64-cell battery pack, built from 18650s harvested from old laptops, the board was sure to have another five miles in it. A custom molded underslung carbon fiber enclosure houses the battery pack and electronics, including the receiver for the handheld remote control and the ESCs for the two motors. Motor mounts were fabbed from aluminum and welded to the trucks, with power transmission through timing belts to 3D-printed pulleys. It’s a good-looking build, and topping out at 22 MPH isn’t too shabby either.

We’ve covered fleets of electric longboards before, from those with entirely 3D-printed decks to one with a flexible battery pack. But we doubt any have the endurance and performance of this board.

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Hacking Together A Temperature Sensor For Boiling Milk

December 27, 2016 by 13 Comments

Ever have trouble justifying your hacking to anyone from another generation? [Domen] presented his mother with a custom-made device that monitors the milk temperature as it boils on the stove, preventing boil-over. And he made the device robust, simple to use, and foolproof. To his mom, it must look like he’s a wizard — able to conjure up home electronics out of solder smoke and some plywood.

Of course, we know better. Inside his gadget is a simple temperature sensor, an ATtiny841, a very nice home-made PCB, a buzzer, an LCD, and some pushbuttons. [Domen] rubbed together a few pre-existing libraries, and had a working prototype inside a nice wooden box on the quick. It’s a simple hack, but imagine how this must look to a muggle. For the detailed incantations, check out [Domen]’s GitHub for the project.

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