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Softwear: New Generation of Wearable Computers

Ramesh Panuganty

Envision a personal computer that goes far beyond Tom Cruise’s wearable informant in Mission Impossible - a computer that actually fits into the heel of a shoe and is powered by the mechanical energy of walking. This is no longer a fantasy, but a reality.

There are many of us who walk around like packed horses with laptop, cell phone, PDA & pager. Not all these things help you everywhere. It is also absurd that these devices can’t talk to each other. Several advancements from the research in hardware, software & communications are changing the world. Let me show you around these technologies, and the way they can simplify anyone’s life. The idea of the new wearable technology is not intended only for personal entertainment, like many of you may be thinking. Let’s go around the world of Wearable Computers to know more.

What is a Wearable Computer?

Boy With Wearable Computer A wearable computer is a computing device small and light enough to be worn on one's body without causing discomfort. Unlike a laptop or a palmtop , wearable computer is constantly turned on and interacts with the a real-world task. Information could be even very context sensitive.

A typical wearable computer consists of a battery or human powered computing unit and carried on a belt or in a jacket. The display would be with a head mounted unit typically a The input is either voice driven or with wireless wrist mounted devices. The data storage is local and does not depend on any network connection.
For hardware and software to comfortably follow you always around, and seamlessly integrate with your style of living, they must merge into softwear. Developing wearable computing requires as much attention to the medium as the message.

Interesting, let me know more

Softwear, being a new dimension in the world of computers, demands a phase shift in the human interaction mechanisms. Let us start our detailed discussion of the wearable computer, with this new implementation of computer & human interaction. The traditional desktop metaphors of command line interface or windows-interface are indeed not at all suitable for wearable computing. These interfaces require a constant user concentration & interaction while performing any task, which is not affordable for a wearable computer. The user’s hands simply may not be free, or the environmental conditions may prevent a good audio input at the time.

Human interaction is just one of the examples of several design requirements in the discussion of wearable computers. You must realize that this is a paradigm shift. Hence you must not compare any of the features to a personal computer or laptop. Think of a wearable computer in a new dimension, and not in traditional terms.

To better understand our discussion ahead, assume a situation of you being in the role of an aero plane pilot. As you walk into the cockpit, you see a sensor indicating a negative correction for zero tail wind. You walk down to the engine room to do a personal check, but need some design specs to isolate the problem. Can you really afford to delay the flight while someone gets the blueprints, or you proceed with the take-off risking all the passengers? You don’t need another person to help you; wearable computer comes of use in these situations. You may browse through the circuit diagrams or manuals while you actually keep inspecting the components & circuits.

How does a Wearable Computer look?

A typical wearable computer will have a motherboard worn inside a fashion garment, connecting all the components of the system. The components will be placed at different parts of the body as per the user convenience; power pack and storage in shoes, display and mic on the glasses and keyboard input on the wrist. User input to the computer is either mostly voice driven or sensed from gestures or body motion. The display and audio output generated by the computer will be relevant to the context and environment.

The below pictures will give you a better idea of how a wearable computer would look like, the component details and the finished personal garment.
Wearable Computer Components Wearable Computer Finished Components

Let’s now look at the components of the wearable computer in detail.

Human Interface System (Humionics)

The user interface for a wearable computer is fundamentally different to those of the regular computers. The ideal human-computer interface for use in a wearable environment would be one which listens for its user, understands what the user has asked it to do as a combination of speech recognition, gestures and a bit of machine vision. The results should be presented back to the user in an intelligent manner, when it is most appropriate and in a suitable format.

Consider an example; a quality inspector looking at car bodies going on the assembly line. He may ask his wearable computer, “when I point that the car on my front has a fault, scan its serial number and record the error”, while pointing the location of the serial number. This type of interaction with a wearable computer, using spoken sentences and gestures, fall under the category of multi-modal and intelligent user interfaces.

Sulawesi Architecture

A framework called Sulawesi has been designed and implemented to tackle what has been considered to be important challenges in a wearable user interface. This framework gives the wearable computer an ability to accept input from any number of modalities, and perform if necessary a translation to any number of modal outputs. This system that has been designed comprises of three distinct parts,

The system gathers real world information through a well-defined API. The current implementation includes keyboard input, network input, speech recognition input, video camera input, G.P.S. input and infrared input. This stage helps in connecting devices on the fly, and provides a device independent abstract layer. Any necessary pre-processing of the data is done in the next stage.
The core of the system contains a basic natural language processor, which performs sentence translations. This converts a sentence into a command stream from which two pieces of information are extracted, which service to invoke and how the output should be rendered. A service manager is responsible for the instantiationand monitoring of the services. The service manager also checks and queues commands to provide resilience against system failures.
The output stage takes a modal neutral result from a service and makes a decision on how to render the information. The decision is made based on two criteria, what the user has asked for, and how the system perceives the users current context/environment.
If the user has asked to be shown a piece of information, this implies a visual rendition. If the system detects that the user is moving or busy with an activity (through the input sensors), an assumption can be made that theuser attention might be distracted if results are displayed in front of him (Imagine what would happen if the user was driving)! In this case the system will override the users request and would redirect the results to a more suitable renderer, such as speech.
A successful wearable user interface must combine different types of input and output, depending on the user's context and needs.

Operating System & Applications

The operating system and the applications are specifically designed bottom-up for a wearable computer, to address the humionics. These should satisfy the below criteria,

Augmented Reality

Wearable computing introduces new concepts ‘mediated reality’ and ‘augmented reality’, which are very interesting to know about.

Mediated reality refers to encapsulation of the user's senses by incorporating the computer with the user's perceptive mechanisms, and is used to process the outside stimuli. For example, one can mediate their vision by applying a computer-controlled camera to enhance it. The primary activity of mediated reality is direct interaction with the computer, which means that computer is "in charge" of processing and presenting the reality to the user.

Augmented Reality combines real world scenes and virtual scenes, augmenting the real world with additional information. The computer must be able to operate in the background, providing enough resources to enhance but not replace the user's primary experience of reality. This can be achieved by using tracked see-through display units and earphones to overlay visual and audio material on real objects. This technology adds value to the human knowledge, memory & intelligence.


An example of an AR application is a guidebook as above. As the tourist walks around the library, his wearable computer uses sensors, for example a combination of GPS and head tracking equipment, to detect his physical position and orientation. Some text describing the library is shown on the display unit over the actual building. The wearable computer assists further in enhancing the value of the real world experience, using augmented reality.

Display Systems

The output device of a wearable computer could be either a head-mounted display (HMD) unit with an earpiece or
only the earpiece for some applications. Though there could be several other display devices intended for specific applications, HMD systems are of interest in the conversation of wearable computers.
Commercial HMD
There are two different types of HMD systems. The first one, intended for industrial or regular use will have a see-through lens and a small projection system. Only on need basis, the processing system may project the output data onto the lens. The projection usually happens only on one of the lenses and the other lens remains free for clear vision.

Entertainment HMD The second type of head-mounted display is of blocking type and requires the full-attention of the user. This is mostly for 3D modeling, used for understanding complex mechanical design systems or for personal entertainment requirements. The HMD systems shown in these pictures have both the earpiece and the mouthpiece built into them. The HMD systems are already well deep into the development cycle as of today, and do support several attractive features like wireless connectivity, external connectors for audio & video, and control settings.

Input Devices

By now, you would probably be having a fair understanding of the criteria of selection for input devices for WCs. But there is no holy grail for an input device of a wearable computer.

Speech recognition may appear as the most suited input device, but may not be preferred in all kinds of applications & environments, due to privacy and performance issues.
Handwriting & Keyboard
could be one of the most efficient input devices, provided the input device is not too small or awkward. Research in this wearable domain is resulting in combination products like the SenseBoard shown in picture. This device is just worn on the hands or wrists and senses the typing input or handwriting. This does not have any cables and communicates on infrared.

Gesture Input devices are simple, compact, and optimized for wearable use. These devices receive inputs from the natural gestures. Ubi-Finger is such a device, but has not been tested for all types of applications.

But the point to be taken is that the user needs to be open-minded and adaptable to the emerging input devices, in order to find the best combination.

Kitty TechThumb Typing - Carsten Mehring, a mechanical engineer at the University of California, Irvine, has come up with a device that turns your hands into a qwerty-style keyboard. Mehring’s device uses six conductive contacts on each thumb—three on the front and three on the back—to represent a keyboard’s three lettered rows. Contacts on the tips of the remaining eight fingers represent its columns. Touching the right index finger to the middle contact on the front of the right thumb, for instance, generates a j. The top contact on the thumb yields a u, while the middle contact on the back of the thumb would produce an h. Mehring says the similarity to typing makes his input device easier to master than others that require an entirely different set of motions. He has applied for a patent and hopes to market a product by year-end of 2002.


We need to discuss two different kinds of networks in reference to a wearable computer. One is to connect the device to the external world and the other is to interconnect the various components, the later one being new for wearable computers.

The first issue of connecting to the WC to the external world has several choices; WAP, or Cellular Digital packet data. This aspect of networking is not specific for a wearable computer, and can evolve over time, from other electronic gadgets.

The second issue of interconnecting the various parts of the WC, may involve both wired and wireless connections. CPU, storage unit and similar peripherals will be connected with or without cables to the wearable motherboard, which is a garment with (physically) flexible bus and standard expansion slots. Peripherals like HMD and wrist/finger worn devices may use standard wireless connections like Bluetooth.

There could also be a third type of communication, two wearable computers talking to each other. This near field networking could be on infrared (IrDA or IRX) or radio based systems, to solve a need, which will invariably arise to exchange information between two users.

Power sources

Batteries add size, weight, and inconvenience to wearable computers. There are several ways of harnessing the energy expended during the user's everyday actions to generate power for one’s computer, thus eliminating the impediment of batteries. However, there is no stopping to use to any of the miniature batteries, for example Lithium, Li-MnO2, Li-C, that are currently being used in electronic gadgets.

Body Bus

Tom Zimmerman of MIT has shown that the non-contact coupling between the user’s body and weak electric fields can be used to create and sense tiny nano-amp currents in the user’s body. Modulating these signals creates Body Net, a personal-area network that communicates through the skin. Using roughly the same voltage and frequencies as audio transmissions, this will be as safe as wearing a pair of headphones.

Keeping data in the human body avoids the intrusion of wires, the need for an optical path for infrared, and conventional problems such as regulation and eavesdropping.

Your shoe computer can talk to a wrist display and keyboard and heads up glasses. Activating your body means that everything you touch is potentially digital. A handshake becomes an exchange of digital business cards, a friendly arm on the shoulder provides helpful data, touching a doorknob verifies your identity, and picking up a phone downloads your numbers and voice signature for faithful speech recognition.

Every emerging discipline in computing is born first as a theoretical approach, almost a dream in the mind of the inventor. Some of such theories have clear practical ramifications, such as encryption algorithms. Others, on the other hand, take some time to evolve from the concepts on paper to something that can be applied in the real world. This could be one such example.

Challenges & Limitations in Wearable Technologies

The biggest challenge in wearable systems is to identify effective interaction modalities for wearable computers. Development of the software for wearable computers which accurately models the common user tasks is probably the most significant challenges faced by wearable system designers.

The other software challenges include integration of information repositories that augment limited device capabilities. Consider a scenario where a streaming video is augmenting the user's visual data coupled with with cross-domain indexing and data correlation.

Coming to the discussion of current limitations on hardware technologies for wearable computing, there are four major problems – power, networking, privacy and interface. Adding more features to the wearable device requires more power and generates more heat. This imposes a restriction to design systems that take little power and little space and last a long time."

To explain the second limitation with networking in wearable devices, first we need to understand that networking may never be truly ubiquitous; there will always be places where access to the Internet will not be simply be available. The inter-component communication using the on-body wireless bus (an internal electrical pathway along which signals are sent from one part of the computer to another) is still an area of research.

Privacy is not yet a limitation, but may be a limitation in future. Wearable computers allow you to have access to information that you normally wouldn’t have. According to Dr starner, one can record conversations, keep personal notes, schedule, and use diary on the wearable. The first part of the privacy is to protect one's own personal information and the second part is to prevent the wearable user from stealing other's information. With massive amounts of information available right on your eyes, the user is expected to use the device judiciously.

The last, the interesting and the most haunting problem is "How do we communicate with the computer and how does it communicate to us?". Which is the most effective way of communciating to the device and back to the human? What are the prime Ergonomics issues and what makes the device more convenient? This answer for this would only evolve along the time, and there may not be any perfect answer to this question.

Applications of Wearable Computing

I will not get surprised if you still ask me this question of "What are wearable computers good for?" and "Can I doMining Engineer using wearable computer something useful with this thing?" Perhaps the strongest reason one should respond with "Many things " and "Yes, you can!" lies in the origin of wearable computing.

You may get surprised to know that wearable computers are already being used, in several fields ranging from medical applications, mining, disability gadgets, defense systems, astronauts, marine engineering and high speed quality assurance processes.

The adjacent photograph shows a real-life example of a mining engineer doing a chemical analysis of a sample live on the field. Time is not very far to see them from coming into as consumer appliances as well.

Privacy & Health Issues

Though wearable computing does not raise any new privacy issues, it is true that the most useful information is also most personal. Just because the wearable computers can be used for surveillance purposes, does not mean that they are being used.

Wearable computing does not involve any privacy issues which otherwise cannot be done. This just helps getting around with what you mostly want, what you mostly do, what you mostly like to do anywhere and everywhere.

Health and Safety considerations will be important when one is wearing these things all his waking hours (and arguably sleeping hours too!). Remember the Carpal Tunnel Syndrome? Last but not the least, the resulting outfits shall be fashionable and provide the buyer with a choice of fashions. After all, one doesn’t want to go to a formal dinner looking like C3PO.


We have all the technologies needed to make a viable wearable computer today. Lot of research and experiments for practical & commercial use of WC are going on around the world. Several varieties of WCs are indeed commercially available, but as of now most of them are tailor made for specific applications. It is only a matter of time before the consumer community accepts the idea, manufactures pick up patron ship and the Catch-22 cycle of mass-production.

The paradigm shift that the WC will bring; computer working along with you instead of you working at the computer, will have similar impact to the paradigm shift brought by the earlier PCs. It will augment the user’s senses, intellect, memory and provide him with huge amount of computation power and information (both local and networked), without interfering from what he doing. Unlike Artificial Intelligence (attempts to emulate human intelligence in the computer), WCs works alongside the human, both doing what each is better at.

After a few cycles of evolution, the wearable computer will become highly ergonomic and a user, over an extended period of usage, will feel it as a true extension of mind and body. The combined capability of resulting synergistic whole will far exceed the “parts”. This will undoubtedly enhance the quality of life of the user, at work place and in all facets of daily life.

References & Acknowledgements

All images in this article have been reproduced with consent from original authors, with due acknowledgements here in the references section.

The Humane Interface by Raskin, Jef. This recently published book goes into greater depth about the advantages of quasimodes and the primacy of text over icons. It also discusses past implementations of the LEAP text navigation method and is a good summary of evaluation techniques for determining quantitative user interface efficiency.

Augmented Reality, Research Projects on Computer Augmented Environment projects at Sony Computer Science Laboratories, Japan

A Wearable Application Integration Framework, Neill J Newman, University of Essex

MIThril, research project at MIT, hardware platform combines body-worn computation, sensing, and networking in a clothing-integrated design. The MIThril software platform is a combination of user interface elements and machine learning tools built on the Linux operating system

Linux Wearable, work being done in the world of linux for enabling wearable technologies

Steve Mann, Univ of Toronto, Keynote address on “Wearable Computing as means for personal empowerment”

Ripley Wearable Computer, Commercial wearable products currently available on linux

Proceedings of The Second International Symposium on Wearable Computers (ISWC '98), 1998 Thad Starner, Brent Schiele, and Alex Pentland. Visual contextual awareness in wearable computing

Wearable Computing, Patrick Sinclair, Intelligence, Agents and Multimedia Group Department of Electronics and Computer Science, University of Southampton

5th International Symposium of Wearable Computers, 2001, Zurich,

Wearable Computer Systems at Carngie Mellon University

Computer-Augmented Vision Technology,

Kitty Tech, Keyboard Independent Touch Typing Method by Dr Karsten Mehring,

Xybernaut, Manufactures of wearable computers, HMD.

Origin Instruments Corpn. - Input devices,

Virtual Vision
: Head Mounted Displays,

Kopin Corpn: Display devices,

i-Glasses: Head Mounted Display Units,

Mobile Augmented Reality Systems (MARS), (c) Columbia University Computer Graphics and User Interfaces Lab.

MIT Media Lab Rich DeVaul Alex "Sandy" Pentland Steve Schwartz

(Article dated: Oct' 2002)