Since Cameron Hoerig is an engineering student at the University of Cincinnati, the idea of building a typical beer pong table was out of the question. "I'm an electrical engineering student, so I should have a table that stands out," says Hoerig.
He built an interactive table. On either end of the table - where the cups stand - there are 10 LED rings composed of eight LEDs each. In the middle of each ring there's a photocell. The Ping-Pong ball triggers the sensors and the gadget's software rotates the LEDs, giving the illusion of a light spinning around the cup.
It's impossible to read the documentation but I'm responding to your problem with inconsistent linearity of photocells. Yes, photocells are imprecise and non-linear. Much of the voltage appears across the limiting resistor. Consider putting a transistor as a constant current source in series with photocells, eliminating the resistor. The voltage across the transistor will be a consistent two diode drops. That way, all the voltage change appears across the photocell. I hope I have understood your problem.
Advertised as the "Most Powerful Tablet Under $100," the Kindle Fire HD 6 was too tempting for the team at iFixit to pass up. Join us to find out if inexpensive means cheap, irreparable, or just down right economical. It's teardown time!
The first photos made with a 3D-printed telescope are here and they're not as fuzzy as you might expect. A team from the University of Sheffield beat NASA to the goal. The photos of the Moon were made with a reflecting telescope that cost the research team £100 to make (about $161 US).
The increased adoption of wireless technology for mission-critical applications has revved up the global market for dynamic electronic general purpose (GP) test equipment. As the link between cloud networks and devices -- smartphones, tablets, and notebooks -- results in more complex devices under test, the demand for radio frequency test equipment is starting to intensify.
Much of the research on lithium-ion batteries is focused on how to make the batteries charge more quickly and last longer than they currently do, work that would significantly improve the experience of mobile device users, as well EV and hybrid car drivers. Researchers in Singapore have come up with what seems like the best solution so far -- a battery that can recharge itself in mere minutes and has a potential lifespan of 20 years.
Focus on Fundamentals consists of 45-minute on-line classes that cover a host of technologies. You learn without leaving the comfort of your desk. All classes are taught by subject-matter experts and all are archived. So if you can't attend live, attend at your convenience.