The diesel engine was, like many things, born of necessity. The main engine types of the day—hot bulb oil, steam, coal gas, and gasoline—were not so thermally efficient or ideal for doing heavy-duty work like driving large-scale electrical generators. But how did the diesel engine come about? Settle in and watch the 1952 documentary “The Diesel Story“, produced by Shell Oil.
The diesel engine is founded on the principle of internal combustion. Throughout the Industrial Age, technology was developing at breakneck pace. While steam power was a great boon to many burgeoning industries, engineers wanted to get away from using boilers. The atmospheric gas engine fit the bill, but it simply wasn’t powerful enough to replace the steam engine.
By 1877, [Nikolaus Otto] had completed work on his coal gas engine built on four-stroke theory. This was the first really useful internal combustion engine and the precursor of modern four-stroke engines. It was eventually adapted for transportation with gasoline fuel. In 1890, the hot bulb oil engine was developed under the name Hornsby-Akroyd and primarily used in stationary power plants. Their flywheels had to be started manually, but once the engine was going, the bulb that drove combustion required no further heating.
Continue reading “Retrotechtacular: The Diesel Story”
Bicycling at night can be a potentially hazardous endeavor for several reasons, but primarily because well, it’s dark. Inattentive drivers, weather, and other factors aside, the most important thing you can do to keep yourself safe is to ensure that you can see and that you are seen by others.
Revolights, an invention put together by [Kent Frankovich, Adam Pettler, and Jim Houk], is an ingenious way of accomplishing both of those things. The ring-shaped system attaches to nearly any bike tire, and includes LEDs that shine like a car’s head and taillights. A magnet attached to the bike’s fork triggers the onboard microcontroller to light only 4 LEDs at a time, letting persistence of vision take care of the rest.
We think it’s a great idea, and clearly others do as well. With nearly a month left on their Kickstarter page, they have nearly doubled their initial funding goal.
Check out the video presentation on their Kickstarter page to get a better look at the Revolights project.
When traveling around the city or even rural areas in a wheelchair, we imagine it can be pretty easy to get overlooked. [Rui] was asked to add some lights and sounds to an electric wheelchair in order to ensure that its rider remained visible to those around him.
The system uses several different components to ensure that the driver can be seen. The first is a message board strapped to the back of the chair which was constructed from a pre-made 8×32 LED matrix enclosed in an acrylic project box. The board uses a PIC16F88 to store and display messages, which are triggered by a control board mounted near the chair’s joystick. He also added headlights and taillights, using bright white and red LEDs, respectively. A 107dB horn was mounted on the chair to ensure that if the driver is not seen, he will certainly be heard.
Everything looks like it fits nicely, without hindering the operation or looks of the chair. Check out the video below to see his high-visibility system in action.
Continue reading “Making wheelchairs more safe through high visibility”
While the Segway enjoyed a few years of fame before falling off the radar, [Marcelo Fornaso] is hoping his creation has quite a bit more staying power. Inspired by the Segway’s ability to balance itself, he started thinking about how the concept could be improved. He felt that one of the Segway’s shortcomings arose out of the fact that the base platform was rigid and required the user to lean back and forth outside the device’s frame in order to turn it. He thought that this made the riding experience uncomfortable as well as risked causing the rider to fall over.
His creation, the Tilto, aims to both improve on the turning ability of the Segway while eliminating the need for handlebars. Based on a tilting mountain board design he had been tossing around for a while, the Tilto uses accelerometers and gyros to keep its balance, much like the Segway. His goal was to keep the vehicle balanced while traveling forwards and backwards, but also allowing the device to tilt from side to side without tipping over. This design keeps the rider mostly upright, allowing the user to direct the vehicle by leaning much like you would on a bicycle.
As you can see in the video below, the Tilto works pretty well, even in its prototype form.
Finally, a people mover that lets us get our gangsta lean on!
Continue reading “Watch out Segway, here comes Tilto”
For day two of Black Hat, we sat in on on [Joe Grand], [Jacob Appelbaum], and [Chris Tarnovsky]’s study of the electronic parking meter industry. They decided to study parking meters because they are available everywhere, but rarely considered from a security perspective.
Continue reading “Black Hat 2009: Parking meter hacking”