Arcade Cabinet Build Takes Quarters, Dispenses Fun

October 9, 2016 by 15 Comments

Building an arcade cabinet seems to be a rite of passage for many hackers and woodworkers. Not that there is anything wrong with that: as this series of posts from [Alessandro] at boxedcnc shows, there is an art to doing it well.

His final build is impressive, with quality buttons, a genuine-looking banner, and even a coin slot so he can charge people to play. His build log covers both the carpentry and electronic aspects of the build, from cutting the panels to his own code for running the coin acceptor that takes your quarter (or, as he is in Italy, Euro coins) and triggers the game to play.

To extract money from his family, he used the Sparkfun COM-1719 coin acceptor, which can be programmed to send different pulses for different coins, connected to an Arduino which is also connected to the joystick and buttons. The Arduino emulates a USB keyboard and is connected to an old PC running MAME with the Attract Mode front end. It’s a quality build, down to the Bubble Bobble banner, and the coin slot means that it might even make some money back eventually.

Cheap 360 Degree Camera

October 9, 2016 by 11 Comments

How much would you pay for a 360 degree camera? How about $15 if you already have a Raspberry Pi and a Pi camera hanging around? If you don’t, you’ll have to add that minimal cost into the build. [Gigafide] noticed how a spherical mirror, made to see around corners, showed an all-around view if you took a picture of it from below. He snagged a panoramic lens made for an iPhone and stripped it for its optics. Some custom software and a little work resulted in a usable 360 degree camera.

SimpleCV (a light version of OpenCV) provides the algorithms to unwrap the frames and you can take video with the setup (see the video below). Mounting the optics took some 3D printing and the Pi operates as a hot spot to send the video out.

Continue reading “Cheap 360 Degree Camera” →

Simulate Your Robot Before You Build It

October 9, 2016 by 12 Comments

[Nurgak] shows how one can use some of the great robotic tools out there to simulate a robot before you even build it. To drive this point home he builds the tutorial off of the easily 3D printable and buildable Robopoly platform.

The robot runs on Robot Operating System at its core. ROS is interesting because of its decentralized and input/output agnostic messaging system. For example, if you leave everything alone but swap out the motor output from actual motors to a simulator, you can see how the robot would respond to any arbitrary input.

[Nurgak] uses another piece of software called V-REP to demonstrate this. V-REP is a simulation suite for robotics and has a few ROS nodes built in. So in order to make a simulated line-following robot, [Nurgak] tells V-REP to send a simulated camera image to the decision making node of the robot in ROS. It then sends the movement messages back to V-REP which drives the pretend robot around.

He runs through a few more examples, proving that it’s entirely possible to become if not a roboticist, at least a really good AI programmer without ever dropping the big money on parts to build a robot.

Two Words That Don’t Mean What You Think They Do

October 9, 2016 by 23 Comments

sprites_enhanced_stripWhen you hear “gravity waves” or “sprites”, you’d think you would know what is being discussed. After all, those ripples in space-time that Einstein predicted would emanate from twin, colliding, black holes were recently observed to much fanfare. And who doesn’t love early 8-bit computer animations? So when we were browsing over at SpaceWeather we were shocked to find that we were wrong twice, in one photo (on the right). Continue reading “Two Words That Don’t Mean What You Think They Do” →

Hackaday Prize Entry: Raspberry Pi Zero Smart Glass

October 8, 2016 by 4 Comments

Some of the more interesting consumer hardware devices of recent years have been smart glasses. Devices like Google Glass or Snapchat Spectacles, eyewear incorporating a display and computing power to deliver information or provide augmented reality on an unobtrusive wearable platform.

Raspberry Pi Zero Smart Glass aims to provide an entry into this world, with image recognition and OCR text recognition in a pair of glasses courtesy of a Raspberry Pi Zero. Unusually though it does not take the display option of other devices of having a mirror or prism in the user’s field of view, instead it replaces the user’s entire field of view with a display and re-connects them to the world through the Raspberry Pi camera.

The display in question is an inexpensive set of “3D Virtual Stereo Digital Video glasses”, of the type that can be found fairly easily on your favourite auction site. They aren’t particularly high-resolution, but the Pi can easily drive them with its composite video output. The electronics and camera are mounted on a headband, in a custom 3D-printed enclosure. All files can be downloaded from the project page.

There is some Python software, but it’s fair to say that there is not a clear demo on the project page showing it working. However this is no reason to disregard this project, because even if its software has yet to achieve its full potential there is value elsewhere. The 3D-printed Raspberry Pi enclosure should be of use to many other similar wearable projects, and we’d almost say it’s worthy of a project all of its own.

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DIY Plant LED Light Prototype Lights Up The Winter

October 8, 2016 by 25 Comments

With winter on the way, our thoughts turn to indoor hacks. And what could be better in the cold winter than fresh veggies? This can be done by replacing the sun with an LED light, and [Margaret Johnson], aka [Bitknitting] has been working on building her own LED plant light.

She’s using a combination of red and blue LEDs that produce the ratio of light frequencies that plants thrive on, and has been experimenting with how bright to make them and how long to run them. This combination of factors determines how much light the plants get every day, called the Daily Light Integral, or DLI, and has a huge effect on how well the plants grow.

Her latest prototype uses nine red and two blue 3 Watt LEDs which run for about twenty hours a day. These lights shine onto the growing area, a bucket filled with nutrient solution. [Margaret] has done an excellent job of outlining why and how she made the choices she did and providing lots of links to more information for the home grower. It’s a great place to start for anyone looking to get something growing indoors in the depths of winter.