” One definition given in a recent review on graphene is:
Graphene is a flat monolayer of carbon atoms tightly packed into a two-dimensional (2D) honeycomb lattice, and is a basic building block for graphitic materials of all other dimensionalities. It can be wrapped up into 0D fullerenes, rolled into 1D nanotubes or stacked into 3D graphite.
A previous definition is:
A single carbon layer of the graphitic structure can be considered as the final member of the series naphthalene, anthracene, coronene, etc. and the term graphene should therefore be used to designate the individual carbon layers in graphite intercalation compounds. Use of the term “graphene layer” is also considered for the general terminology of carbons.”
Right now Diveduino will not replace your dive computer, but it can log your depth and temperature during your dive, saving it to a MicroSd Card in a TEXT file format so you can import it to excel and do your fancy dive profile graphics, no need of special $100 USD cables that all the diving equipment manufacturing companies sell. Plus it has a display for that information with a actual graph of your dive profile.How it came to my mind?
DiveDuino came to my mind since I am an active diver and I enjoy the sport. I am an electrical engineer and at work I came across with the Arduino platform. Dive computers are expensive, if you want all the fancy features, you can find some computers for about $150 USD and others for about $1500 USD. Every basic dive computer has this indicators: No Decompression Limit(NDL), depth, temperature and elapsed time. So why not create something with the help of the Arduino open source platform, I found a sensor that could interact with Arduino and the rest is the prototype that I am building.”
How to make a very slim watch and keep battery life long? In this Hack-a-Gecko project, they tried to catch two birds with one stone.
We thought it would be cool to utilize the extremely low power EFM32 in combination with an extremely low power display to create a wrist watch demo application. And usually, the smaller and thinner something is, the cooler it is. (Admittedly, wrist watches do not necessarily follow this trend… big watches.)
Anyway, we wanted it slim. The starting point was the memory LCD display from Sharp (link). It is truly a Nano ampere display technology. And it is also thin, only 0.75 mm. A watch also needs a battery, cool new technologies exist such as the Thinergy battery, but the voltage of 4.1 V is a bit awkward. We decided to use a standard 3.0V CR1616 cell as it can power the EFM32 and display directly. Thickness of battery + display is 2.35 mm, is it possible to design the electronics as well within this thickness limit…? Challenge accepted!”
That’s cool, on http://blog.section9.co.uk/2010/03/iphone-rfid-reader.html you can see the work process in pictures. The RFID chip is from http://www.id-innovations.com/new%20launch.htm.
“The idea behind this project is to see what the iPhone’s serial is capable of and to try and have a little fun with RFID along the way. This reader works with the low frequency (125Khz) tags but I have a half working version for MiFARE Hi-Frequency as well.”
“It has 2 analog inputs and can supply 5V ont the 4 pins header on the right.One of the inputs can be scaled down with the trim pot.
The firmware in the Tiny45 is written in C and compiled with Winavr and usb source code from obdev. As you can see, there is no crystal , the software sync the internal 16.5Mhz pll clock with the USB clock.
The cost with a home made pcb is around 5€.
Of course, do not expect 1Gs/s HID does not alow that data rate ! But it is using a 10bits AD.”
“My Z80 microcomputer is hand wired using the wire-wrap prototyping technique. This method uses thin 30 gauge wire, a special wire-wrap tool, and wire-wrap sockets. The sockets have 1/2 inch long square posts, which you use the tool to wrap (or twist) the wire onto the post. As long as you have 5 or more wraps on the post for a single wire, the connection is semi-perminant. This method was used because it’s easy to change connections and is faster than soldering each wire. Wire-wrapping was a popular method used in building early computers. In fact, the AGC computer used for the NASA Apollo missions were completely wire-wrapped! After I finished my computer, I went through more than 350 feet of wire!”
“This article shows how to build a small, cheap and simple frequency meter, without any fancy, out of reach components. The simple proposed design can measure frequencies up to 40 Mhz with errors below 1%! This degree of precision will be more than enough to debug most of your analog and digital circuits, and will give you the ability to analyze many aspects that you were unable to see before.”
“Essentially he took the MyVu headset, removed one of the eye pieces, and mounted the other to his glasses to that he could see his surroundings and the UX’s screen at the same time. The MyVu is attached to the UX through the A/V output port on the UX’s port replicator dongle. With some additional addons he provided his UX with extra battery life via an external battery, and several input methods to communicate with the UX while the rest of the kit resides within the backpack.
Battery geek: BG 14-18-60External battery (60wh)
Motorola iDen i425 (for next-to-nothing (but half dial up speed) always-on internet access)
Modified MyVu Crystal Head Mounted Display
Bluetooth enabled cellphone (text and mouse input)
Bluetooth stereo headset (voice input and stereo output)
“Familiar with the concept of hardware keylogging? A hardware keylogger is a perfect solution for monitoring user activity, at very low risk of disclosure. A hardware keylogger is a purely electronic device, so no access to the operating system is required, no traces are left, and software has no possibility of detecting such a device. However, the hardware keylogger concept inherits one weakness: physical access to the keylogger is required for retrieving captured data. This problem has finally found it’s solution: a Wireless Keylogger.”
“This article is the first of a series that will document the development of a low cost, open source wireless streaming internet radio receiver. All construction details, including schematics, source code, and even the design process itself will be documented on this blog.”
“This is a Propeller laptop – with a 6502 co-processor and 64K of static RAM! The Propeller handles all I/O for the 6502 and runs an integrated debugger so you can program the computer. The Propeller serves as the programmable chipset for this 6502 laptop. You could use an FPGA in this capacity, but could you easily do this and implement visual debugger software inside an FPGA? Over the years hardware prototyping has evolved from building-block hardware (TTL) to programmable hardware (PLA’s and FPGA’s). I believe the Propeller represents the next revolution: 100% software-based virtual hardware – and I built this laptop to prove it!
I’ve always want to design a computer from scratch, but modern CPU’s are too complex, run too fast, and have too many fiddly little pins to be any use in a DIY project. An older processor like the 6502 is much easier to work with, yet you can still learn about computer architecture from it. If you think an 8 bit processor is irrelevant because it is old, consider that just because 8 bit technology is out of fashion, does not mean the principles of computing have changed. These principles, like mathematical concepts such as π and square roots, do not become obsolete just because they are old.”
“We bridge the gap between the virtual world and the real world
Our purpose at ioBridge is to remove all the hurdles involved with connecting DIY projects to the web. This goal has been out of reach for all but the most tech savvy. Controlling or monitoring devices over the web requires proficiency in circuit design, network architecture, scripting languages and website design. Even if all those requirements are met, connectivity issues between devices on a local network and the web render many projects impractical.”
“A few years back a good friend of my said to me “I have this great idea, lets mount a paint ball gun on an X,Y turret and make a huge inkjet printer!” After a little research we found that it had already been done… (and the time that it has taken me to get this published the MythBusters have done it as well, search youtube)
Eventually we setteled on a servo driven mirror to aim laser light at photo paper to create a “Laser Printer”"
“A desktop machine that will measure out a length of wire and strip a length from either end.
To create lengths of wire that fit perfectly into an electronics breadboard. (we produce kits and you can only hand cut and strip so many wires before you go crazy)
This is also the first item in a concept oomlout.com is working on dubbed “open manufacturing”. (more to follow)
It breaks down into three parts
1. Wire Feeder – This feeds the wire in measured lengths forwards and backwards (uses a stepper motor)
2. Wire Stripper – This runs an exacto knife blade around the insulation of the wire twice. (uses a small servo motor and normal sized servo motor)
3. Wire Snipper – Snips the wire at the end. (uses a pair of wire cutters and a cheap handheld drill motor)”
“The “Ethernet Picture Viewer” is a low cost device that allows a user to visualize graphic content stored on a computer in an LAN. A server application that runs on a PC serves requests from the “Picture Viewer” and provides image data to be displayed on the device’s LCD. The user is offered the possibility to browse among the various pictures that are made public by the server application , choose one and scroll the displayed image.”
“The PIR sensor is used to detect when someone enters the room, the system will then turn on the lights, the door contacts and the pressure sensor will be used in conjuction with the PIR to determine if someone is still in the room, (possibly sitting on the toilet!) so the lights wont turn off while the person is still in the room. Each user will have an RFID tag or iButton , so each users utility usage can be datalogged on the PC. Each user will have a preset amount of time in the shower, the system will alert the user when their time is almost up. The Proximity sensor will be used to detect a user and control the faucet water flow. The humidity sensor will be used to control the exhaust fan, if someone is using the shower, or steam builds up in the room, the exhaust fan will be turned on automatically. An application on the PC side will enable the Administrator to override any functions remotely, or view”