Guysoft shows us how to create a Bumble-b LED Matrix Computer Interface. I have never used a Bumble-b but for $17 how could you go wrong? It seams like one of the best ways to communicate directly via USB to a computer.

Via: HG Forum

"After getting my LED matrix to display messages, I wanted to make use of the USB port, and get the matrix to work as a USB device, this was much simpler than I expected. Once I had the code to control the matrix, it was simply a matter of copying it and using LUFA. LUFA (Lightweight USB Framework for AVRs) is a library that will let you get the Bumble-b to work as a USB device."

This POV Fan Display Hack by Hacking with Gum required a bit of reverse engineering to determine how the device worked in the first place, then a way to re-program the operation of the device to display a new message.

 Thanks Craig.

"It turns out that Cenzic made it very easy to access the fan’s EEPROM chip, and with a simple RS232-to-I2C interface you can re-write the EEPROM on this device to make it display whatever you like. "

This is a cool scale mod. The Weight Logging Bathroom Scale saves the the time stamped weight for each use to an SD card. This allows the data to be plotted and analyzed. The method that the weight was taken from the existing digital scale platform is real interesting. The original LCD data lines were snooped on to determine what value is being displayed!

Thanks Jorge.

"First I thought that I could read the sensors and got an analog voltage relative to weight but I couldn’t find a way to do it. Next a friend at work give me the idea to try read the signals that went to original LCD, and it was a simple and easy way to have what I need The original LCD have 15 pins, 3 backplanes and 12 segments. I did understand how the LCD signals works reading this application note. The segments signals have voltage that can be read directly by the LPC2103. The backplanes signals can’t be ready directly by the LPC2103 (I think) and then I made a very simple voltage detector using a LM258 opamp so I get a "trigger" signal every time the backplane signal get near is maximum value."

Norris Labs has created an interesting Robot called the ChessBot. It doesn’t actually play the game but rather has the ability to move the chess pieces around the board. Just imagine playing a game of chess on this system via webcam instead of playing virtual chess on the net.

"ChessBot takes a hybrid approach that produces a more visually interesting way to move a chess pieces. It uses a Lynxmotion AL5D robotic arm to pick up and place pieces but does not rely totally on the arm to provide placement. The arm itself is mounted on a mobile platform (called the Cart) that can align the arm precisely with any row or column (called Rank and File in the chess world) on the chessboard."

In the video the Spooky Dropper is setup to deliver a bat right in front of the victim. It could drop a spider, ghost, rat or anything else you can dream up! It can reset itself automatically using one normal servo and one that has been modified for continuous operation. This is begging to be hooked up to a motion detector or even the door bell circuit to launch at just the right time. To see the full documentation of Vern Graner’s project have a look at the Halloween edition of Nuts and Volts Magazine.

If you have a Halloween project of your own, why not add it to the list of projects in the Show us your Halloween Project Contest.

Remember Carl that made the Spinning RGB LED Ball Display? He has also built a wicked RGV Laser System! I can just imagine using this at the center of a big party. You would have to pass out eye protection though.

"Three laser beams in primary red, green and violet are combined with the optics harvested from an HD-DVD drive to make white. The total output is 350-400mW, and wavelengths are 660, 532 and 405nm. The homemade TTL constant current driver modulates the lasers to simulate over 16 million colours from an ordinary RGB LED-circuit with PWM, amplified by transistors."

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I shudder at the thought of soldering up this Surface Mount LED Array from bear24rw. Have a look at the build, the circuit board was designed and etched by hand and the picture documentation is very good. These are the same guys that made the RFID Doorm Room Unlocker.

Thanks Max.

"The driver we choose to design was highly inspired from this one. The basic idea is that you use shift registers to sink the columns and a line driver of some sort to source the rows (we chose to use a Darlington array).

There where a lot of changes from the Instructables design that that we had to make however. The matrix in the Instructables was a lot smaller than ours and used 8 IO lines to drive each row. Since our matrix has 16 rows this was completely infeasible using just an ATMega168. To solve this issue we choose to use a 4:16 de-mux to control all sixteen rows with only 4 IO pins."