Reverse engineering radio controlled outlets

[Chr] picked up a pack of remote control outlets in order to reverse engineer them and build control into his own projects. These can be plugged into outlets around your house and a relay inside each module will switch whatever device is plugged into it after receiving a command from the remote. Once he cracked open the control housing it was easy to find the data line for the RF module which was on its own board. He used a logic analyzer to capture data from various button presses and then spent some time¬†deciphering¬†the communication protocol. He used what he learned to roll the module and code into an interface box where an ATmega8 connects via USB and passes commands from a computer to the RF board. Now he’s added home automation via a computer quite inexpensively. After the break you can watch a clip of the outlets switched using a smartphone.

So why not just patch into the buttons on the remote? Well, this same project was attempted at our local hackerspace earlier this month and the buttons don’t just pull a pin to ground. They use tri-state logic and are arranged into a matrix that is a lot harder to mimic (if not impossible) with a microcontroller. Analyzing the communications going into the RF module is definitely the less labor-intensive of the two approaches.

Continue reading “Reverse engineering radio controlled outlets”

12 foot LED display keeps your office informed

Don’t reach for a sticky note when you need to leave a message for your office mates, write it down on a 12 foot LED marquee. [Kitesurfer1404] built this for his home office, but we’re sure he’ll find fun stuff to use it for. The display has 512 LEDs driven by plain old 595 shift registers for the high-side columns, with an ULN2803A Darlington Array to pull the eight rows to ground. The whole thing is controlled by an ATmega8 via a serial connection. Our compliments to the builder for accurately drilling a grid of 64×8 holes in each hardboard panel of the display. The buses for each row and column also look nice and clean. For the final look a 79% light transmittance frosted acrylic panel was added to diffuse the light.

We used the same method to build our LED pumpkin. Transistors ran the low side, and if we had needed more columns, shift registers are a popular go-to for I/O expansion. Check out that project to learn more about display multiplexing.

ROS gains full body telemetry

[Taylor Veldrop] has been playing with an NAO robot and ROS, mixed with a Kinect to get some pretty amazing results. The last time we saw any work done with ROS and the Kinect, it was allowing some basic telemetry using the PR2. [Tyler] has taken this a step further allowing for full body control of the NAO robot. Basic mimicking mixed with a little bit of autonomy allow the NAO to follow his steps around a room and even slice a bananna, or hammer nails. We think this is pretty impressive, especially if he were to mix it together with a motion tracking stereoscopic display. Follow along after the break to see it pull off some of these cool feats.

Continue reading “ROS gains full body telemetry”