Virtual Pool, Real-world Interface

[youtube=http://www.youtube.com/watch?v=2Wc_DXGe2fQ]

Sunday we saw robots playing pool and an augmented reality pool game. Today we’ll complete the pool trifecta: virtual pool using a real cue stick and ball in another vintage video from Hack a Day’s secret underground vault. The video is noteworthy for a couple of reasons:

First is the year it was made: 1990. There’s been much buzz lately over real-world gaming interfaces like the Nintendo Wii motion controller or Microsoft’s Project Natal. Here we’re seeing a much simpler but very effective physical interface nearly twenty years prior.

Second: the middle section of the video reveals the trick behind it all, and it turns out to be surprisingly simple. No complex sensors or computer vision algorithms; the ball’s speed and direction are calculated by an 8-bit processor and a clever arrangement of four infrared emitter/detector pairs.

The visuals may be dated, but the interface itself is ingenious and impressive even today, and the approach is easily within reach of the casual garage tinkerer. What could you make of this? Is it just a matter of time before we see a reader’s Mini-Golf Hero III game here?

Touch Sensitive Keypad

capacitive_keypad

[Viacheslav] built a keypad that uses human capacitance to detect key presses. Unlike normal keys which close a physical connection, his project detects touch through the PCB substrate. He uses the analog comparator of an AVR ATmega8 to detect the moment of zero crossing and then measures the time it takes to discharge in order to detect key presses.

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Vintage Video: Computing Across America

roberts

in 1983, [Steve Roberts] packed up a Tandy 100 laptop and a 5-watt solar panel, fleeing suburbia on his recumbent bicycle on what would become a 17,000 mile journey that forever cemented his place in the geek pantheon…not just as a technology hacker, but as one of the preeminent “life hackers,” pursuing his own dreams on his own terms and inspiring others to do the same.

In this 1989 video, recently unearthed by Hack a Day, [Roberts] reflects on the first 16,000 miles of his voyage, detailing some of the technology that went into his then-current ride, the Winnebiko II.

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Build Your Own Joystick

macgyver_joystick

What can you build with a ballpoint pen and some extra parts? [gzip] found himself with a bonus box of right angle switches and other miscellaneous parts and set out to build a joystick. Simple arcade joysticks use switches that are actuated by the movement of the stick and this design embraces the concept. The four tactile switches are mounted on protoboard facing each other with part of a ballpoint pen in the middle. When the pen is moved it presses against one or more switches to close, completing a circuit. For good measure he even incorporated a fire button into the top of the “stick”. Now we just need someone to make this work with a tiny Ms. Pac-Man emulator.

8-bit Binary Calculator

binary_calculator

Don’t feel like shelling out $5 for a fancy factory made calculator that won’t even do binary math? [Jeff] decided to prove his mastery of gates and his disdain for base 10 by building a binary calculator using XOR, AND, and OR chips. Calculations can be input in two ways: through digital logic headers or by three banks of DIP switches used to enter the operator and the two operands. Although limited to addition and subtraction, this is a great way to make sure you really understand digital logic. Take a look at the rough design schematics in his album. The design is modular so if you have one of each gate and a few LEDs sitting around you can give this a whirl.

Grow Box Controls Heater, Fans, And Water

grow_box_controller

The Cheap Vegetable Gardner wanted more automation than their previous PS2 controller based grow system. This time they set out to design a full featured, compact grow controller that can measure temperature and humidity as well as control a heat lamp, fan, and water pump. An Arduino provides USB connectivity and interfaces the solid state relays and sensors. The assembled project all fits in a box but we are left wondering how much heat the four SSRs generate and will it be a problem?

[Thanks shawn]

Color Changing Paint Display

heat_actuated_display

We’ve seen several creative projects from [Sprite_tm] and this one sets a new bar. He got his hands on some paint that changes color with temperature. By covering a circuit board with the paint then heating the circuits he’s created a heat actuated 7-segment display (his post is in Dutch). Three seconds at about 1 amp is enough to turn the black paint white. When the segment has been disconnected for about one minute the paint fades back to black. Now that we’ve seen his concept, leave a comment and tell us how you’d use it.