Robotic Advances Promise Artificial Legs That Emulate Healthy Limbs

Robotic Advances Promise Artificial Legs That Emulate Healthy Limbs

 Recent advances in robotics technology make it possible to create prosthetics that can duplicate the natural movement of human legs. This capability promises to dramatically improve the mobility of lower-limb amputees, allowing them to negotiate stairs and slopes and uneven ground, significantly reducing their risk of falling as well as reducing stress on the rest of their bodies.

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For the last decade, Goldfarb's team has been doing pioneering research in lower-limb prosthetics. It developed the first robotic prosthesis with both powered knee and ankle joints. And the design became the first artificial leg controlled by thought when researchers at the Rehabilitation Institute of Chicago created a neural interface for it.

In the article, Goldfarb and graduate students Brian Lawson and Amanda Shultz describe the technological advances that have made robotic prostheses viable. These include lithium-ion batteries that can store more electricity, powerful brushless electric motors with rare-Earth magnets, miniaturized sensors built into semiconductor chips, particularly accelerometers and gyroscopes, and low-power computer chips.

The size and weight of these components is small enough so that they can be combined into a package comparable to that of a biological leg and they can duplicate all of its basic functions. The electric motors play the role of muscles. The batteries store enough power so the robot legs can operate for a full day on a single charge. The sensors serve the function of the nerves in the peripheral nervous system, providing vital information such as the angle between the thigh and lower leg and the force being exerted on the bottom of the foot, etc. The microprocessor provides the coordination function normally provided by the central nervous system. And, in the most advanced systems, a neural interface enhances integration with the brain.

Unlike passive artificial legs, robotic legs have the capability of moving independently and out of sync with its users movements. So the development of a system that integrates the movement of the prosthesis with the movement of the user is "substantially more important with a robotic leg," according to the authors.

Not only must this control system coordinate the actions of the prosthesis within an activity, such as walking, but it must also recognize a user's intent to change from one activity to another, such as moving from walking to stair climbing.

Identifying the user's intent requires some connection with the central nervous system. Currently, there are several different approaches to establishing this connection that vary greatly in invasiveness. The least invasive method uses physical sensors that divine the user's intent from his or her body language. Another method -- the electromyography interface -- uses electrodes implanted into the user's leg muscles. The most invasive techniques involve implanting electrodes directly into a patient's peripheral nerves or directly into his or her brain. The jury is still out on which of these approaches will prove to be best. "Approaches that entail a greater degree of invasiveness must obviously justify the invasiveness with substantial functional advantage…," the article states.

There are a number of potential advantages of bionic legs, the authors point out.

Studies have shown that users equipped with the lower-limb prostheses with powered knee and heel joints naturally walk faster with decreased hip effort while expending less energy than when they are using passive prostheses.

In addition, amputees using conventional artificial legs experience falls that lead to hospitalization at a higher rate than elderly living in institutions. The rate is actually highest among younger amputees, presumably because they are less likely to limit their activities and terrain. There are several reasons why a robotic prosthesis should decrease the rate of falls: Users don't have to compensate for deficiencies in its movement like they do for passive legs because it moves like a natural leg. Both walking and standing, it can compensate better for uneven ground. Active responses can be programmed into the robotic leg that helps users recover from stumbles.

Before individuals in the U.S. can begin realizing these benefits, however, the new devices must be approved by the U.S. Food and Drug Administration (FDA).

Single-joint devices are currently considered to be Class I medical devices, so they are subject to the least amount of regulatory control. Currently, transfemoral prostheses are generally constructed by combining two, single-joint prostheses. As a result, they have also been considered Class I devices.

In robotic legs the knee and ankle joints are electronically linked. According to the FDA that makes them multi-joint devices, which are considered Class II medical devices. This means that they must meet a number of additional regulatory requirements, including the development of performance standards, post-market surveillance, establishing patient registries and special labeling requirements.

Another translational issue that must be resolved before robotic prostheses can become viable products is the need to provide additional training for the clinicians who prescribe prostheses. Because the new devices are substantially more complex than standard prostheses, the clinicians will need additional training in robotics, the authors point out.

In addition to the robotics leg, Goldfarb's Center for Intelligent Mechatronics has developed an advanced exoskeleton that allows paraplegics to stand up and walk, which led Popular Mechanics magazine to name him as one of the 10 innovators who changed the world in 2013, and a robotic hand with a dexterity that approaches that of the human hand.

New Hologram Technology Created With Tiny Nanoantennas

New Hologram Technology Created With Tiny Nanoantennas

Researchers have created tiny holograms using a "metasurface" capable of the ultra-efficient control of light, representing a potential new technology for advanced sensors, high-resolution displays and information processing.

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The metasurface, thousands of V-shaped nanoantennas formed into an ultrathin gold foil, could make possible "planar photonics" devices and optical switches small enough to be integrated into computer chips for information processing, sensing and telecommunications, said Alexander Kildishev, associate research professor of electrical and computer engineering at Purdue University.

Laser light shines through the nanoantennas, creating the hologram 10 microns above the metasurface. To demonstrate the technology, researchers created a hologram of the word PURDUE smaller than 100 microns wide, or roughly the width of a human hair.

"If we can shape characters, we can shape different types of light beams for sensing or recording, or, for example, pixels for 3-D displays. Another potential application is the transmission and processing of data inside chips for information technology," Kildishev said. "The smallest features -- the strokes of the letters -- displayed in our experiment are only 1 micron wide. This is a quite remarkable spatial resolution."

Findings are detailed in a research paper appearing on Friday (Nov. 15) in the journal Nature Communications.

Metasurfaces could make it possible to use single photons -- the particles that make up light -- for switching and routing in future computers. While using photons would dramatically speed up computers and telecommunications, conventional photonic devices cannot be miniaturized because the wavelength of light is too large to fit in tiny components needed for integrated circuits.

Nanostructured metamaterials, however, are making it possible to reduce the wavelength of light, allowing the creation of new types of nanophotonic devices, said Vladimir M. Shalaev, scientific director of nanophotonics at Purdue's Birck Nanotechnology Center and a distinguished professor of electrical and computer engineering.

"The most important thing is that we can do this with a very thin layer, only 30 nanometers, and this is unprecedented," Shalaev said. "This means you can start to embed it in electronics, to marry it with electronics."

The layer is about 1/23rd the width of the wavelength of light used to create the holograms.

The Nature Communications article was co-authored by former Purdue doctoral student Xingjie Ni, who is now a postdoctoral researcher at the University of California, Berkeley; Kildishev; and Shalaev.

Under development for about 15 years, metamaterials owe their unusual potential to precision design on the scale of nanometers. Optical nanophotonic circuits might harness clouds of electrons called "surface plasmons" to manipulate and control the routing of light in devices too tiny for conventional lasers.

The researchers have shown how to control the intensity and phase, or timing, of laser light as it passes through the nanoantennas. Each antenna has its own "phase delay" -- how much light is slowed as it passes through the structure. Controlling the intensity and phase is essential for creating working devices and can be achieved by altering the V-shaped antennas.

The work is partially supported by U.S. Air Force Office of Scientific Research, Army research Office, and the National Science Foundation. Purdue has filed a provisional patent application on the concept.

Machines Learn to Detect Breast Cancer

Machines Learn to Detect Breast Cancer

Software that can recognize patterns in data is commonly used by scientists and economics. Now, researchers in the US have applied similar algorithms to help them more accurately diagnose breast cancer. The researchers outline details in the International Journal of Medical Engineering and Informatics.

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Duo Zhou, a biostatistician at pharmaceutical company Pfizer in New York and colleagues Dinesh Mittal and Shankar Srinivasan of the University of Medicine and Dentistry of New Jersey, point out that data pattern recognition is widely used in machine-learning applications in science. Computer algorithms trained on historical data can be used to analyze current information and detect patterns and then predict possible future patterns. However, this powerful knowledge discovery technology is little used in medicine.

The team suggested that just such an automated statistical analysis methodology might readily be adapted to a clinical setting. They have done just that in using an algorithmic approach to analyzing data from breast cancer screening to more precisely recognize the presence of malignant tumors in breast tissue as opposed to benign growths or calcium deposits. This could help improve outcomes for patients with malignancy but also reduce the number of false positives that otherwise lead patients to unnecessary therapeutic, chemotherapy or radiotherapy, and surgical interventions.

The machine learning approach takes into account nine characteristics of a minimally invasive fine needle biopsy, including clump thickness, uniformity of cell size, adhesions, epithelial cell size, bare cell nuclei and other factors. Trained on definitive data annotated as malignant or benign, the system was able to correlate the many disparate visual factors present in the data with the outcome. The statistical model thus developed could then be used to test new tissue samples for malignancy.

First Virtual Surgery With Google Glass

First Virtual Surgery With Google Glass

 A University of Alabama at Birmingham surgical team has performed the first surgery using a virtual augmented reality technology called VIPAAR in conjunction with Google Glass, a wearable computer with an optical head-mounted display. The combination of the two technologies could be an important step toward the development of useful, practical telemedicine.

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VIPAAR, which stands for Virtual Interactive Presence in Augmented Reality, is a UAB-developed technology that provides real time, two-way, interactive video conferencing.

UAB orthopedic surgeon Brent Ponce, M.D., performed a shoulder replacement surgery on Sept. 12, 2013 at UAB Highlands Hospital in Birmingham. Watching and interacting with Ponce via VIPAAR was Phani Dantuluri, M.D., from his office in Atlanta.

Ponce wore Google Glass during the operation. The built-in camera transmitted the image of the surgical field to Dantuluri. VIPAAR allowed Dantuluri, who saw on his computer monitor exactly what Ponce saw in the operating room, to introduce his hands into the virtual surgical field. Ponce saw Danturuli's hands as a ghostly image in his heads-up display.

"It's not unlike the line marking a first down that a television broadcast adds to the screen while televising a football game," said Ponce. "You see the line, although it's not really on the field. Using VIPAAR, a remote surgeon is able to put his or her hands into the surgical field and provide collaboration and assistance."

The two surgeons were able to discuss the case in a truly interactive fashion since Dantuluri could watch Ponce perform the surgery yet could introduce his hands into Ponce's view as if they were standing next to each other.

"It's real time, real life, right there, as opposed to a Skype or video conference call which allows for dialogue back and forth, but is not really interactive," said Ponce.

UAB physicians say this kind of technology could greatly enhance patient care by allowing a veteran surgeon to remotely provide valuable expertise to less experienced surgeons. VIPAAR owes its origins to UAB neurosurgeon Barton Guthrie, M.D., who some ten years ago grew dissatisfied with the current state of telemedicine.

"So called 'telemedicine' was little more than a telephone call between two physicians," Guthrie recalled. "A surgeon in a small, regional hospital might call looking for guidance on a difficult procedure -- one that perhaps I'd done a hundred times but he'd only done once or twice. How advantageous to the patient would it be if we could get our hands and instruments virtually into the field of a surgeon who has skills and training and lacks only experience?"

"The paradigm of the telephone consultation is, 'Do the best you can and send the patient to me when stable', while the paradigm with VIPAAR is 'Get me to the patient.' Let's get my expertise and experience to the physician on the front line, and I think we can implement that concept with these technologies," Guthrie said.

Ponce says VIPAAR allows the remote physician to point out anatomy, provide guidance or even demonstrate the proper positioning of instruments. He says it could be an invaluable tool for teaching residents, or helping surgeons first learning a new procedure.

"This system is able to provide that help from an expert who is not on site, guiding and teaching new skills while enhancing patient safety and outcomes," he said. "It provides a safety net to improve patient care by having that assistance from an expert who is not in the room."

In 2003, Guthrie approached the Enabling Technology Laboratory in UAB's Mechanical Engineering Department, which was already at work on virtual, interactive technologies, with the idea of using two-way video to enhance surgery. The resulting technology became VIPAAR, now a start-up company at Innovation Depot, a technology business incubator partnered with UAB.

"VIPAAR brings experts or collaborators to the site of need, in any field where a visual collaboration would be beneficial," said Drew Deaton, CEO of VIPAAR. "VIPAAR uses video on mobile devices to allow experts or collaborators to connect in real time and not only see what might need to be fixed, corrected or solved, but also be able to reach in, using tools or just their hands, and demonstrate. It's like being there, side by side with someone when you might be a thousand miles, or 10 thousand miles away."

Deaton says potential applications for VIPAAR go beyond medicine and surgery. He says field service is a burgeoning area, from a service call to fix a home heating system, to keeping an industrial manufacturing process on line and running.

"When there is a breakdown, the time to respond and resolve an issue is critical in the field service world," Deaton said. "VIPAAR is helping field service engineers solve problems as fast as possible and get their customers up to speed as fast as possible."

Ponce and Dantuluri were pleased with the results of their interactive collaboration. Adjustments will be needed to fine tune the marriage between VIPAAR and Google Glass, but the promise of useful, practical telemedicine is drawing ever closer. Deaton calls it one more step on the technology evolutionary ladder.

"Today, you can't imagine having a phone without the capability to take picture, or a video," he said. "I can't imagine, five years from now, not being able to use a smart phone to connect to an expert to solve my problem. And have that person reach in and show me how to solve that problem, because the technology is advancing rapidly and we're bringing this technology to market today."

Inkblots Improve Security of Online Passwords

Inkblots Improve Security of Online Passwords

Carnegie Mellon University computer scientists have developed a new password system that incorporates inkblots to provide an extra measure of protection when, as so often occurs, lists of passwords get stolen from websites.

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This new type of password, dubbed a GOTCHA (Generating panOptic Turing Tests to Tell Computers and Humans Apart), would be suitable for protecting high-value accounts, such as bank accounts, medical records and other sensitive information.

To create a GOTCHA, a user chooses a password and a computer then generates several random, multi-colored inkblots. The user describes each inkblot with a text phrase. These phrases are then stored in a random order along with the password. When the user returns to the site and signs in with the password, the inkblots are displayed again along with the list of descriptive phrases, the user then matches each phrase with the appropriate inkblot.

"These are puzzles that are easy for a human to solve, but hard for a computer to solve, even if it has the random bits used to generate the puzzle," said Jeremiah Blocki, a Ph.D. student in computer science who developed GOTCHAs along with Manuel Blum, professor of computer science, and Anupam Datta, associate professor of computer science and electrical and computer engineering.

These puzzles would prove significant when security breaches of websites result in the loss of millions of user passwords - a common occurrence that has plagued such companies as LinkedIn, Sony and Gawker. These passwords are stored as cryptographic hash functions, in which passwords of any length are converted into strings of bits of uniform length. A thief can't readily decipher these hashes, but can mount what's called an automated offline dictionary attack. Computers today can evaluate as many as 250 million possible hash values every second, Blocki noted.

Given the continued popularity of easy passwords, such as "123456" or "password," it's not always difficult to crack these hashes. But even hard passwords are vulnerable to the latest brute force methods, Blocki said.In the case of a GOTCHA, however, a computer program alone wouldn't be enough to break into an account.

"To crack the user's password offline, the adversary must simultaneously guess the user's password and the answer to the corresponding puzzle," Datta said. "A computer can't do that alone. And if the computer must constantly interact with a human to solve the puzzle, it no longer can bring its brute force to bear to crack hashes."

The researchers described GOTCHAs at the Association for Computing Machinery's Workshop on Artificial Intelligence and Security in Berlin, Germany, Nov. 4.

Because the user's descriptive phrases for inkblots are stored, users don't have to memorize their descriptions, but have to be able to pick them out from a list. To see if people could do this reliably, the researchers performed a user study with 70 people hired through Mechanical Turk. First, each user was asked to describe 10 inkblots with creative titles, such as "evil clown" or "lady with poofy dress." Ten days later, they were asked to match those titles with the inkblots. Of the 58 participants who participated in the second round of testing, one-third correctly matched all of the inkblots and more than two-thirds got half right.

Blocki said the design of the user study, including financial incentives that were too low, might account for the less-than-stellar performance. But he said there also are ways to make descriptions more memorable. One way would be to use more elaborate stories, such as "a happy guy on the ground protecting himself from ticklers."

Virtually Numbed: Immersive Video Gaming Alters Real-Life Experience

Virtually Numbed: Immersive Video Gaming Alters Real-Life Experience

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Role-playing video games can alter our experience of reality and numb us to important real-life experiences, a new study finds.

Spending time immersed as a virtual character or avatar in a role-playing video game can numb you to realizing important body signals in real life. This message comes from Ulrich Weger of the University of Witten/Herdecke in Germany and Stephen Loughnan of Melbourne University in Australia, in an article in the journal Psychonomic Bulletin & Review, published by Springer.

The researchers studied what happens when gamers take on the role of -- and identify with -- a nonhuman character such as an avatar during immersive video gaming, and how it especially influences their experience of pain. Avatars often have automaton-like, robotic characteristics such as mechanistic inertness, rigidity and a lack of emotion and warmth.

Participants were asked how much time they spend each week playing video games. Their responses were then correlated with a measure of pain tolerance by counting the number of paperclips that they could retrieve from ice-cold water. In a second experiment, participants played either an immersive or a nonimmersive computer game before taking part in the same pain-resistance task. The immersive video-game players exhibited a reduced sensitivity to pain and removed significantly more paperclips from ice-cold water. They were also more indifferent to people depicted as experiencing displeasure than were the nonimmersive players.

Weger and Loughnan found that by taking on and acting from the perspective of an automaton-like avatar, people are desensitized to pain in themselves and in others. The point of view adopted during video gaming appears to have implications that extend beyond the virtual environment, into real life.

Dr. Weger points to what he sees as a misleading development: that the human-machine boundary is increasingly being blurred, either by humans entering virtual machines/robots, or by anthropomorphizing, in other words adding human qualities to animated figures and toys. Machines are being programmed to attract human inclinations, while virtual characters and robots have started to perform tasks or roles that were traditionally held by humans, such as that of robot counselling therapists. In such an environment it becomes increasingly easy and normal to regard artificial beings as being akin to human beings.

"We see this blurring as a reality of our time but also as a confused and misleading development that has begun to shape society," says Weger. "We believe this should be balanced by other developments, for example, by working on our awareness of what it really means to be human. We should also look into how we can best make use of the beneficial applications of robotic or artificial intelligence advances, so as to be able to use our freed up resources and individual potentials wisely rather than becoming enslaved by those advances."

FACEBOOK THRIFTS

FACEBOOK THRIFTS

Thrift is a software library and a set of code generation tool which was developed at the Facebook Office at Palo Alto, California, to expedite development and implementation of scalable and efficient backend services. The primary goal of thrift is enable efficient and reliable communication across programming languages by abstracting the portions of each language that tend to require the most customization into a common library that is implemented in each language.

 This is done by allowing the users to define the data types and service interfaces in a common Interface Definition Logic File (IDL File) which is supposed to be language neutral file and it generates all the necessary code to build Remote Procedure Calls to clients and servers. This report explains the design choices and implementation level details and also tries to demonstrate a sample Thrift Service.

The whole concept of Thrift stemmed out from the fact that a new direction was required to tackle the resource demands problems for many of Facebook's on-site applications, which couldn’t be addressed by staying within the LAMP framework. LAMP is the acronym for Linux, MySQL, Apache and PHP. When Facebook was being laboriously designed, it was done from ground up using this LAMP framework. By 2006 Facebook was widely accepted all over the world as the social networking site and consequently its network traffic also grew giving rise to the need for scaling its network structure for many of its onsite applications like, search, ad selection and delivery and event logging.

Scaling these operations to match the resource demands was not possible within the LAMP framework. In their implementation of creating many of these services like search, event logging various programming languages had been selected to optimize for the right combination of performance, ease and speed of development, availability of existing libraries etc. Also a large portion of the Facebook's culture has always preferred to choose the best tools and implementations over the standardizing on any one programming language and begrudgingly accepting its inherent limitations. Most of the programming languages either suffered from subpar performance or constrained data type freedom. Given all these technical challenges and design choices, the engineers at Facebook were presented with a herculean task of building a scalable, transparent and high performance bridge across various programming languages.

Thrift Design Features

The primary idea behind Thrift is that it consists of a language neutral stack which is implemented across various programming languages and an associated code generation engine which transforms a simple interface and data definition language into client and server remote procedure call libraries. Thrift is designed to be as simple as possible for the developers who can define all the necessary data structures and interfaces for a complex service in a single short file. This file is called as Thrift Interface Definition Logic File or Thrift IDL File. The developers identified some important features while evaluating the technical challenges of cross language interactions in a networked environment.

Types of thrifts

A common type system should exist across all the programming languages without requiring the need for the developers to write their own serialization code. Serialization is the process of transforming an object of one type to another. For example if a programmer has written an application implementing a strongly typed STL map for a Python dictionary. Neither programmer should be forced to write any code below the application layer. Dictionary is a data type in Python which allows sequencing a collection of items or elements using keys. It is very similar to 'Associative Arrays'.

Transport

Each language must have a common interface to bidirectional raw data transport. Consider a scenario where there are 2 servers in which, one is deployed in Java and the other one is deployed in Python. So a typical service written in Java should be able to send the raw data from that service to a common interface which will be understood by the other server which is running on Python and vice-versa. The Transport Layer should be able to transport the raw data file across the two ends. The specifics about how this transport is implemented shouldn’t matter to facebook thrifts.The service developer. The same application code should be able to run against TCP Stream Sockets, raw data in memory or files on disk.

Protocol

In order to transport the raw data, they have to be encoded into a particular format like binary, XML etc. Therefore the Transport Layer uses some particular protocol to encode or decode the data. Again the application developer will not be bothered about this. He is only worried whether the data can be read or written in some deterministic manner.

Versioning

For the services to be robust they must evolve from their present version. They should incorporate new features and in order to do this the data types involved in the service should provide a mechanism to add or delete fields of an object or alter the arguments list of a function without any interruption in service. This is called Versioning.

Processors

Processors are the ones which process the data streams and accomplish Remote Procedure Calls.

Thrift allows programmers to develop completely using thrift's native data type rather than using any wrapper objects or special dynamic types. It also does not require the developer to write any serialization code for transport. The developer is given the freedom to logically annotate their data structures in Thrift Interface Definition Logic File (IDL File), with minimal amount of extra information necessary to tell the code generator how to safely transport the objects across languages.

Structs

A thrift struct defines a common object to be used across languages. A struct is essentially similar to a class in object oriented programming languages. A Thrift struct has a strongly typed field with unique field identifiers. The basic syntax for Thrift struct is very similar to the structs used in C. The fields in a Thrift struct may be annotated with unique field identifiers unique to the scope of the struct and also with optional default values. The concept of field identifiers can be omitted also and this concept of field identifers was introduced strictly for versioning purposes.

This is how a Thrift Struct looks like:

struct Example

{

1: i32 number =10, 2: i64 bignumber,

3: double decimals,

4: string name= “NB”

};

As you can see the fields inside the Thrift struct are labeled with unique field identifiers.

Facebook Thrift Services

Thrift has been employed in a large number of applications at Facebook, including search, logging, mobile, ads and the developer platform. Two specific usages are discussed below.

Search

Thrift is used as the underlying protocol and transport layer for the Facebook Search service. The multi-language code generation is well suited for search because it allows for application development in an efficient server side language (C++) and allows the Facebook PHP-based web application to make calls to the search service using Thrift PHP libraries. There is also a large variety of search stats, deployment and testing functionality that is built on top of generated Python code. Additionally, the Thrift log file format is used as a redo log for providing real-time search index updates. Thrift has allowed the search team to leverage each language for its strengths and to develop code at a rapid pace.

Logging

The Thrift FileTransport functionality is used for structured logging. Each service function definition along with its parameters can be considered to be a structured log entry identified by the function name. This log can then be used for a variety of purposes, including online and offline processing, stats aggregation and as a redo log.

Thrift has enabled Facebook to build scalable backend services efficiently by enabling engineers to divide and conquer. Application developers can focus on application code without worrying about the sockets layer. We avoid duplicated work by writing buffering and I/O logic in one place, rather than interspersing it in each application. Thrift has been employed in a wide variety of applications at Facebook, including search, logging, mobile, ads, and the developer platform. We have found that the marginal performance cost incurred by an extra layer of software abstraction is far eclipsed by the gains in developer efficiency and systems reliability. Finally Thrift has been added to Apache Software Foundation as the Apache Thrift Project, making it open source framework for cross-language services implementation.

BLUEJACKING

BLUEJACKING

Bluejacking is the sending of unsolicited messages over Bluetooth to Bluetooth-enabled devices such as mobile phones, PDAs or laptop computers, sending a vCard which typically contains a message in the name field (i.e. for bluedating or bluechat) to another Bluetooth enabled device via the OBEX protocol. Bluetooth has a very limited range usually around 10 meters on mobile phones, but laptops can reach up to 100 meters with powerful transmitters.

 Bluejacking allows phone users to send business cards anonymously using Bluetooth wireless technology. Bluejacking does not involve the removal or alteration of any data from the device. Bluejackers often look for the receiving phone to ping or the user to react. In order to carry out a bluejacking, the sending and receiving devices must be within 10 meters of one another. Phone owners who receive bluejack messages should refuse to add the contacts to their address book. Devices that are set in non-discoverable mode are not susceptible to bluejacking.

Mobile phones have been adopted as an everyday technology, and they are ubiquitous in social situations as users carry them around as they move through different physical locations throughout the day. As a communicative device, the mobile phone has been gradually taken up in ways that move beyond merely providing a channel for mediated conversation.

One such appropriation is bluejacking, the practice of sending short, unsolicited messages via Vcard functionality to other Bluetooth-enabled phones. To choose the recipients of bluejacks, senders complete a scan using their mobile phones to search for the available Bluetooth-enabled devices in the immediate area. A bluejacker picks one of the available devices, composes a message within a body of the phone‟s contact interface, sends the message to the recipient, and remains in the vicinity to observe any reactions expressed by the recipient.

The messages tend to be anonymous since the recipient has no idea who has sent the bluejack, and the recipient has no information about the bluejacker, except for the name and model of the bluejacker‟s mobile phone. Because of Bluetooth‟s short-range networking capabilities, bluejacking can only occur between actors who are within 10 meters of each other, which makes this activity highly location-dependent.

 Contrary to what the name suggests, the bluejack recipient‟s phone is not hijacked; that is, the phone is at no time under the control of the bluejacker. Bluejackers, however, ignore the conflict between the control exerted by the bluejacker and the lack of defensive measures that can be taken by the recipient when his or her possessional territory is violated. To gain a further understanding of why bluejackers would engage in a practice that disrupts the social conventions of public space, we ask the following research questions:

·         What are the characteristics of the public spaces in which bluejacking occurs?

·         What are the alternative social conventions that might arise from the practice of bluejacking?

·         What implications does this appropriation have for the design of mobile social systems?

This bluejack phenomenon started after a Malaysian IT consultant named “Ajack” posted a comment on a mobile phone forum. Ajack told IT Web that he used his Ericsson cellphone in a bank to send a message to someone with a Nokia 7650. Becoming bored while standing in a bank queue, Ajack did a Bluetooth discovery to see if there was another Bluetooth device around. Discovering a Nokia 7650 in the vicinity, he created a new contact and filled in the first name with „Buy Ericsson!' and sent a business card to the Nokia phone. How To Bluejack Assuming that you now have a Bluetooth phone in your hands, the first thing to do is to make sure that Bluetooth is enabled. You will need to read the handbook of the particular phone (or PDA etc) that you have but somewhere in the Menu item you will find the item that enables and disabled Bluetooth. Now, remember that Bluetooth only works over short distances, so if you are in the middle of Dartmoor then BlueJacking isn't going to work for you (unless the sheep have mobile phones these days!) so you need to find a crowd. BlueJacking is very new so not everyone will have a Bluetooth phone or PDA so the bigger the crowd the more likely you will have of finding a 'victim'. The Tube (yes, Bluetooth works underground), on the train, in a Cafe or standing in line are all good places to start.

You will now need to create a new Contact in your Phone Book - however rather than putting someone's name in the Name field you write your short message instead - so for example rather than creating a contact called Alan Philips you would write - "Hey, you have been BlueJacked!" instead (or whatever message you want to send) Now select the new contact and from the Menu of the phone choose "Send via Bluetooth".

This is a facility available within the Mobile Phone that was designed to send a Contact to someone else - useful in Business when trading names and addresses, however we are now going to use it to send our message that was contained in the Name field of the contact - clever eh? Your phone or PDA will start to search the airwaves for other devices that within range. If you are lucky you will see a list of them appear, or it will say that it cannot find any. If the latter happens then relocate to another crowd or wait a while and try again. If you have a list of found devices then let the fun begin. Unfortunately, almost every Bluetooth enabled device will not yet be configured with a useful name - so you are going to have to guess. Some devices will be called by their Phone manufacturer (e.g. Nokia, Sony) or maybe a random string. Try one at random and look around to see who grabs their phone and then looks perplexed when they read your message :) If you want to name your Phone so it appears as a name in the list on a BlueJackers phone see how to name our phone .You can build a library of contacts with predefined messages.

 The various steps involve in this are as follows:

 1. First press the 5-way joystick down.

 2. Then choose options.

 3. Then choose "New contact"

 4. Then in the first line choose your desired message.

 5. Then press done.

 6. Then go to the contact.

 7. Then press options.

 8. Then scroll down to send.

 9. Then choose "Via Bluetooth"

10. Then the phone will be searching for enabled Devices.

11. Then press "Select"