Transmitting Power And Data Through Thick Metal Enclosures

So let’s say you have a submarine, or a nuclear containment chamber which has walls made of thick metal. Now let’s say you want to transmit power or data through this wall. Obviously you’re not going to want to drill a hole since this wall is either keeping seawater out, or potential contamination in, but wireless signals aren’t going to travel well through dense metal. [Tristan Lawry’s] entry in the Lamelson-MIT Rensselaer Student Prize seeks to address this issue by using ultrasound waves to transmit data and power.

In the video after the break [Tristan] speaks briefly about his project, then demonstrates the transmission of power and digital audio simultaneously through a two-inch thick steel plate. This is accomplished with a set of piezo transducers attached to both the inside and outside of the plate. Communications originate by feeding electricity to one transducer, which sends ultrasonic vibrations through the material to be received by its counterpart on the other side. It’s easy for us to understand data transmission conducted in this manner, after all that’s how the knock block receives information. What we don’t understand is how it can “transfer large amounts of electrical power”. If you can explain it in layman’s terms please do so in the comments.

Continue reading “Transmitting Power And Data Through Thick Metal Enclosures”

Sound-sensitive Android Figure Speaks In Morse Code

mechanized_android_figure

Instructables user [tanbata] recently got his hands on a Google Anroid figurine and thought that while it looked great, it served no real purpose. He decided to change that, and converted this once-useless hunk of plastic into a miniature robot that moves and responds to sound.

He pried of the head of the figure and got busy fitting a servo into the Android’s body to enable head movement. An ATiny was added to control the figure, along with a microphone to enable it to respond to sound. A piezo was inserted to relay Morse code messages, and a handful of LEDs were installed in the body cavity and eyes of the figure just for kicks.

When the bot is powered on and senses a loud enough sound, the eyes light, the head spins from side to side, and the robot spouts off a random message in Morse code as you can see in the video below.

It’s not the most advanced project out there, but with a few tweaks, it could make for a great USB-powered email or IM notification system for your PC. Better yet, it’s a great project to do with a child who is interested in electronics, since they get to make a cool robot toy they can keep.

Continue reading “Sound-sensitive Android Figure Speaks In Morse Code”

Multitool Alarm System

Here’s a way to make sure you don’t leave your Leatherman multitool somewhere. It’s an alarm system that will start a timer when the tool is removed from the holster. After five minutes the module beeps to remind you to put the tool back where it belongs. Annoying? Possibly, but if you’re not done with your work just press the reed leaf switch on the module to reset the timer. A PIC 12F683 handles the timing and generates the waveform for the piezo buzzer. Perhaps this could have been accomplished with a dual 555 chip like the LM556 (one timer for the countdown and another for the piezo waveform) but the PIC has power-down modes available that should make the button batteries last a long time.

Radios Without Power Sources

[Goodhart] is sharing his process for building a couple different AM radios. It’s surprising how few components he’s using; the first build is just a germanium diode, some wire, and a piezo earpiece. But it strikes us that both of the radios he gives build instructions for have no power source. We’re also amused by the process of selecting the station. His example uses 770 AM, and requires you to take the wire and place it up in a tree with the two ends about 1216 feet apart. We think there’s something a bit off with the math, but with that much conductor to start with there might be enough induced current for you to actually hear something come out the piezo. We don’t think we’ll be trying this anytime soon, but we’d like to hear comments from those of you who do (or already have).

Hackaday Unleashes A Troll Sniffing Rat

Sometimes we like to take a few minutes away from Hackaday to spend time with our families. But just when you take your eyes off of the incoming comments, Trolls are bound to strike. Well, [Caleb] and I found a solution to the problem in the form of a troll sniffing rat. This beady-eyed vermin sits on my desk and waits. When a trolling comment is detected its eyes glow red and an alarm is sounded. Join us after the break for more about this silly project.

Continue reading “Hackaday Unleashes A Troll Sniffing Rat”

Inkjet Print Head Made With A 3D Printer

This is an inkjet print head made using a RepRap. The manufacturing process is both simple and ingenious. It uses a vibrating piezo buzzer to pump printing liquid through a tiny nozzle. The red disc seen above is exactly the same diameter as the piezo that resides behind it. There is a hole offset from the center to feed ink in between the two discs. Take a look at the test footage after the break.

To make the nozzle a hole was cut in the plastic disc, then a pin inserted and the whole thing was covered with hot glue. The next step was to remove the pin and shave down the glue until the narrow aperture is open. [Adrian Bowyer] is still in the testing phase for this assembly, but once he gets the bugs worked out he plans to test it with a heating element so that it can print using wax and other materials that are liquid when hot.

[Vik] tipped us off about this one after seeing the printable transistors from the other day.

Continue reading “Inkjet Print Head Made With A 3D Printer”

Power All Over Your Body

We know that you can transform the mechanical motions of your body into electrical energy, like when you turn the crank or shake a mechanically-powered flashlight. These types of mechanical motions are quite large compared to many of the day-to-day (and minute-to-minute) actions you perform–for example walking, breathing, and thumb wrestling.

What if we could harvest energy from these tiny movements? Researchers at the Korea Advanced Institute of Science and Technology are seeking the answer to this question with piezoelectric barium titanate. The electrical output of their devices is very small (in the nanoAmps) but over a long period and over many repetitions it would be possible to run a small electric device–even a biologically-embedded one. An alternative to blood power?

There is clearly a lot of potential in this technology, and we’ll be interested to see if and when we can start messing around with this stuff. Heck, it’s already been used to power a small LED and you all know just how much everyone would jump at the chance to cover themselves in self-powered LEDs…