We have featured DIY Induction Heaters here before. There is something about heating a big chunk of metal with no contact that is so appealing. Uzzors2k has a great write-up about his experiments with his Induction Heater, it is filled with trial and error which we can all learn from. 

"To test my new driver I had a large work coil and tank capacitor already built for a previous induction heater project. The tank capacitor was made up of 50x 22nF and 50x 12nF mini capacitors I purchased cheaply off ebay, giving a total of 1.7µF at 600V. So far I’ve had 3 capacitor failures, all of them with the small 12nF ones. Other than that the bank has held up well and doesn’t seem very lossy. The most difficult component to construct was the matching inductor, which dissipates surprising amounts of power due to the large current flow. After a few failed attempts I had to use 32 strands of 0.3mm magnet wire, wrapped together as litz wire. Even with just 8.6 milli-Ohms of DC resistance I still had to use a fan to keep the inductor temperature low enough."

Using a hall effect device a magnet is allowed to hover in mid air. A microcontroller monitors the hall effect feedback to determine how close the magnet is and adjusts the strength of the electromagnet to attract the magnet or allow it to drop. This calculation and adjustment is performed so quickly that the magnet appears to remain at a constant height.

Project Page

Thanks for the tip Chris.

Greg Pyes has done a great job of hiding a huge Subwoofer in a Floor Cavity. He took pictures along the way so that you too can have your thumping bass and no big speakers in sight.

David from Volunteer Lab Rats is playing with his new ADXL202 Accelerometer. He documented the results so that we can be a few steps closer to getting it to work when we rig one up.

"The board is supplied with +5v and ground. There are two output pins on the board. They each output the square shaped signal seen on the picture below. The duty cycle of the signal corresonds to the acceleration in the X- and Y- direction. The duty cycle grows when the accelerometer is moved in the one direction, and shrinks when moved in the opposite direction."

MechRC is a cool new robot that is very technical but unlike other applications of technology where the product becomes more complex this device is simplified by it. Unlike most programming where you need to enter complex commands to be executed with this robot you simply show it what you would like! Our friends over at Trossen Robotics are the first in the United States to offer the robot, it isn’t cheap though. At almost $600.00 I hope you have a bit saved up in your robot fund already.

"High torque metal gear servos, LiPo batteries for longer run times, a fluid 3D visual software programming interface for easy custom motions, and a remote control unit are included. Everything you need to have you own walking robot is included in this ready-to-walk kit! With over a hundred pre-installed motions and sounds you can get this robot throwing some dance floor shapes or some killer fighting moves straight from the box.

Features:

• The MechRC Robot comes pre-assembled.
• Designed by the Transformer artist so there is a startling likeness to the Transformer form.
• The ‘bot sports 17 servos with 180 degree movement..
• Metal Gear Servos with 13kg-cm torque!
• Audio can be played through the speaker in the robot’s chest.
• More than 100 moves are pre-stored on the robot – see him throw some serious shapes fit for the dance floor or reveal his killer fighting moves.
• An easy to use 3D visual interface is used for programming.
• The robot is manipulated in an animation film strip making customizing seriously user-friendly.
• IR remote control.
• Lithium battery pack and charger.
• MechRC Commander software CD ROM.
• USB/Serial communications cable.
• User Guide.
• Requires a PC (not Mac compatible).
• Suitable for ages 14 years+.
• Size: 36 x 32 x 15cm."

Cisco is running a cool contest with some wicked prizes. The top prizes are two $10,000 giveaways! All you need to do is record a 3 minute video about either your digital heaven or hell. You have until November 26th to enter so you will have to act fast.

Here are two of my favorite videos:
Ken’s Retro Crib
Fully Automated and Wired House!

"Submit a video (up to 3 minutes long) showing off your digital crib for an opportunity to win. Show us how clever and efficient you are with consumer technology and your home network or issue a plaintive cry for professional help. The Grand Prize Winners (one for Heaven and one for Hell) will each receive a prize of $10,000. Additionally, ten finalists (five in each category) win a $500 gift card."

Thanks for the tip Shawn.

Steve from Finkbuilt has put together a cool DIY FOG Screen, unlike the commercial models that cost tens of thousands he built his on a DIY hobbyist budget. The video shows a perfect application which is a scary Halloween evil eye.

"The effect uses rear-projection video, shined onto a screen of water vapor created by ultrasonic atomization, that is sandwiched between 2 laminar airflows, which keep the sheet of fog contained. The commercial Fog Screen that spits out this screen costs tens of thousands of dollars for the small one."

(more…)