LED matrix shield starts with a very loud snap

We see a lot of LED matrix projects. They’re fun, and you can learn a lot of basic lessons during the build. But this one is out of the ordinary. [Rtty21] built an oddly sized, and sound controlled matrix shield for his Arduino. That’s it right there, the shield is the large chunk of protoboard but you can just see the Arduino peeking up over the top of it.

Now we say oddly sized because a 9×9 matrix doesn’t make much sense with an 8-bit micro controller. There’s no schematic but in the clip after the break he mentions that the columns and rows are driven by a decade counter and shift register and that’s what makes it possible to drive nine bits easily. Also of note on the board is that washer above and to the right of the matrix. It’s a touch-sensitive reset button. But the main control mechanism is a Clapper clone circuit. Just snap your fingers and it turns the project on or off. [Rtty21] based the design on this step-by-step sound input build.

[Read more…]

Reinventing The Clapper with a knock-based home automation controller

Clap On!… Clap Off!… was super awesome when The Clapper came out in the mid-eighties. Now [Mathieu Stephan] is trying to make the concept much more functional. He put together a controller that lets you knoch on walls to control things around the house. It’s called the Toktoktok project and uses small boxes to receive user input and control items like lamps and computers.

A piezo element picks up the noises made by a user. Above [Mathieu] demonstrates how sensitive the element is, picking up scratching and knocking anywhere along this wall and displaying it as a waveform on the computer monitor. Clever processing and filtering of these noises lets the device convert them into different commands. He covers all of this in the video after the break, then demonstrates a bunch of functionality such as waking up and starting audio playback from a computer just by tapping on the coffee table.

This isn’t the first time we’ve seen the concept. One of our favorites is this door lock which listens for the secret knock. But [Mathieu] is trying to extend the functionality and bring it to a more general market. [Read more…]