Ridiculous Exerciser Becomes Useful As A Charger

November 22, 2010 by Mike Szczys 41 Comments

[Scott Nietfeld] built a charger from a Dyna-flex wrist exerciser. We hadn’t heard of a these gyroscopic devices before but once we saw the promo video (embedded after the break) we realized that this is the kind of thing that infomercials were made to sell. [Scott] knew the internals spun to fairly high RPM and figured that adding a few magnets on the inside and coils on the outside would turn this thing into a generator. Four rare-earth magnets fit the bill, with two external coils feeding a rectifier and linear regulator. Below you can see his demonstration video where he takes the orb apart, then spins it up, generating 250 mA at about 7.5 volts to drive the regulator and charge a cellphone. Not bad!

Continue reading “Ridiculous Exerciser Becomes Useful As A Charger” →

SmartLCD Makes Video For Microcontrollers Easy

November 21, 2010 by Mike Szczys 28 Comments

[Rossum] developed a host board that makes it easy to drive a TFT screen using an inexpensive microcontroller. He’s looked around at a bunch of LCD’s that are easy to get your hands on and decided that the iPod Nano 2G screens are the right balance of performance (176×132 TFT) and low cost ($1-$5). They’re not particularly difficult to talk to, but with 22 pins they’re a bit hardware hungry.

He takes us through the signal sniffing he used to figure out the communications process. From there he harness the power of an ARM Cortex M0 processor, which he’s worked with in the past, to drive the screen. His implementation results in a driver board called the SmartLCD that takes care of the screen’s parallel protocol, power, and backlight. From there it’s just four connections and you can use a small microcontroller like the Arduino seen above with ease. See what it can do after the break.

Continue reading “SmartLCD Makes Video For Microcontrollers Easy” →

LED Wall And Kinect Join Forces

November 21, 2010 by Mike Szczys 11 Comments

[Alex] wrote in to let us know about this Kinect controlled LED wall that was whipped up at the Tetalab hackerspace in Toulouse, France. The wall, which was built earlier in the year, uses some MAX7313 LED intensity controlling shift registers. Each gets its own board and controls the intensity of sixteen different red LEDs. They’re embedded in the wall module and covered with ping-pong balls as diffusers.

The recent activity on the project takes advantage of the Xbox Kinect. As you can see in the video after the break, they’ve used the open source Kinect drivers to capture 3D environment data, processing it into color gradients which are displayed on the Pong wall. Shouldn’t be long before they someone comes knocking on their door to install this in a dance club. We love the effect, especially because it works in a dark room and the LEDs don’t cause any interference with the video capture.

Continue reading “LED Wall And Kinect Join Forces” →

Motion Activated Wildlife Camera (or A Spy Device)

November 21, 2010 by Mike Szczys 20 Comments

Now you can capture pictures of our furry friends by building a motion activated wildlife camera. [Doug Paradis] took his Air Freshener hack and used it to trigger a camera. The white dome in the picture above is the PIR sensor from an Air Wick Freshmatic, along with a cheap keychain camera and an MSP430 microcontroller. He used one of the chips that came with the TI Launchpad, a transistor, and some discreet components to interface the devices and then put them into a project box. Now he’s got a fully configurable motion-sensing camera.

Adding Pan And Tilt To A Webcam

November 21, 2010 by Mike Szczys 11 Comments

[Brent] and his wife wanted a way to provide more family time for Grandparents that lived far away. They tried a webcam, but their daughter just didn’t oblige by staying in the frame. Instead of chasing her around the room with with the camera he added pan and tilt features to the device. He settled on IR control using a common television remote, similar to our USB remote control receiver tutorial except that it drives servo motors instead of forwarding signals over the serial connection. [Brent] used a Picaxe 08M, connecting two servos together as a base on top of the project box. If you try this yourself there’s a lot of room to grow. Once you’ve assembled the hardware it wouldn’t be too hard to make this web enabled so that Grandpa can click on a web interface to look around the room.

AVR Programming 04: Writing Code, Etc.

November 19, 2010 by Mike Szczys 24 Comments

Welcome back to this fourth and final installment of the series. The first three parts should have been enough to get you off the ground, but a few more learning examples wouldn’t hurt. It’s also a good time to discuss some of the other things these little chips can do. Join me after the break to:

Expand the sample code, adding features to our simple program while I challenge you to write the code yourself.
Discuss AVR fuse bits, how to use them, and what to watch out for
Touch on some of the peripherals you’ll come across in these chips

As a grand flourish to the series, I’ve used the example hardware from this final part to build a bicycle tail light. Hopefully this will inspire you to create something much more clever.

Series roadmap:

Continue reading “AVR Programming 04: Writing Code, Etc.” →

Communicating With An LED Matrix

November 19, 2010 by Mike Szczys 9 Comments

Most of the LED matrix posts we run delve into the hardware design. This time around [J Bremnant] used prefab modules and focused on writing code to address the display. The hardware combines two 24×16 LED boards from Sure Electronics with a Teensy 2.0 to drive the display and provide a USB connection. The firmware comes in just under 8k, leaving graphic manipulation up to a PC.

[J Bremnant’s] Python script offers a lot of flexibility when working with the display. There are three modes selectable through a terminal interface. One just tests the display and then drops into Conway’s Game of Life. The second mode lets you send commands via serial interface so it can be used as a message ticker. The final feature is frame addressing that allows graphics to be dropped into the display. See each of these featured in the video after the break.

Continue reading “Communicating With An LED Matrix” →