Ambient Intelligence: Changing Forms of Human-Computer Interaction and their Social Implications
Ambient intelligence (AmI) is a burgeoning field of information systems that has potential for great impact in the future. The term "ambient" is defined by Merriam-Webster's dictionary (Mish and Morse 1999) as "existing or present on all sides". The term Ambient Intelligence is defined by the Advisory Group to the European Community's Information Society Technology Program (ISTAG) as "the convergence of ubiquitous computing, ubiquitous communication, and interfaces adapting to the user" (Gupta 2003). Ubiquitous should also be defined since the core realm of AmI envelops this concept. Ubiquity involves the idea that something exists or is everywhere at the same time on a constant level, for example, hundreds of sensors placed throughout a household. This idea is important when trying to understand the future implications that AmI will have on the environments we live and function in. Indeed, our research suggests that the onset of AmI will revolutionize business, government, and everyday life in a manner tantamount to the personal computing revolution of the 1980s and 1990s. As more and more attention and effort is directed towards developing AmI to its full potential, the question of how we will all be affected by it, both positively and negatively, requires consideration.
The objective of AmI is to broaden the interaction between human beings and digital information technology through the use of ubiquitous computing devices. Conventional computing primarily involves user interfaces (UIs) such as keyboard, mouse, and visual display unit; while the large ambient space that encompasses the user is not utilized as it could be. AmI on the other hand uses this space in the form of, for example, shape, movement, scent and sound recognition or output. Again we can refer to the example of the all-encompassing sensors in households. These information media become possible through new types of interfaces and will allow drastically simplified and more intuitive use of devices. Wireless networks will be the dominant technology for communication between these devices. The combination of simplified use and their ability to communicate will eventually result in increased efficiency for users and will, therefore, create value, leading to a higher degree of ubiquity of computing devices. Examples of such devices range from common items such as pens, watches, and household appliances to sophisticated computers and production equipment.
This paper examines the digital information technology behind AmI, its business value and potential weaknesses, as well as the changes AmI makes to personal and professional lives.
AmI is comprised of three main components: ubiquitous computing , ubiquitous communication, and user adaptive interfaces.Weiser (1991)
coined the term "ubiquitous computing", referring to omnipresent computers that serve people in their everyday lives at home and at work, functioning invisibly and unobtrusively in the background and freeing people to a large extent from tedious routine tasks. The general working definition of ubiquitous computing technology is any computing technology that permits human interaction away from a single workstation. This includes pen-based technology, hand-held or portable devices, large-scale interactive screens, wireless networking infrastructure, and voice or vision technology (Abowd 2004).
In its ultimate form, ubiquitous computing means any computing device, while moving with you, can build incrementally dynamic models of its various environment and configure its services accordingly. The devices will be able to either "remember" past environments they operated in, or proactively build up services in new environments (Lyytinen and Yoo 2002). In its 1999 vision statement, the European Union's Information Society Technologies Program Advisory Group (ISTAG) used the term "ambient intelligence" in a similar fashion to describe a vision where "people will be surrounded by intelligent and intuitive interfaces embedded in everyday objects around us and an environment recognizing and responding to the presence of individuals in an invisible way" (Ahola 2001).
One of the most significant challenges in AmI/pervasive computing technologies is to create user-friendly interfaces. Developing interfaces for ubiquitous computing is a rather new field. A number of the technologies initially developed actually increased inefficiencies in the way users learned or worked. Human computer interaction designers are still struggling to establish usable standards for these technologies (Bohn et al. 2004, Davis 2002).
Today, numerous objects are equipped with computers, i.e. our environment already exhibits a relatively high level of ubiquitous computing. However, in most cases the computers do not operate at their full potential since they are unable to communicate with each other. A major change in the corporate and home environments that will promote ubiquitous communication and, thereby, ubiquitous computing is the introduction and expansion of wireless network technology, which enables flexible communication between interlinked devices that can be stationed in various locations or can even be portable. To implement wireless technology on a wide level, however, the wireless hardware itself must meet several criteria on the one hand, while easy integration and administration as well as security of the network must be ensured on the other.
The following list presents different wireless technologies that are available on the market or currently under development. The main factors to be considered when selecting the technology are physical size, range of operation, data transfer rate, and price. Physical size may become a critical factor due to space constraints, especially in mobile applications. Following Moore's law, wireless hardware has been decreasing in size considerably and can nowadays be placed on small microchips. The University of California, Berkeley demonstrated this by building a wireless sensor only 2.0 by 2.5 mm in size that can transmit data at a speed of 19,200 kbit/s over a range of up to 40 feet (Yang 2003).
- Wireless LAN (W-LAN) applications per standard IEEE 802.11b offer high-speed transfer rates of 11 Mbit/s and can be extended over entire office buildings and production areas by using several access points. While W-LAN is, according to Laudon and Laudon (2004), considerably cheaper than a traditional stationary LAN, it is often still too costly to be included in small individual devices (Ailisto et al. 2003).
- Bluetooth technology is used in today's handheld applications like cellular phones or personal digital assistants (PDAs) per standard IEEE 802.15 to allow wireless connection within a personal area network (W-PAN). While the cost of Bluetooth equipment is significantly lower than the cost of W-LAN, the transmission range of up to 10 meters and the data transfer rate of less than 720 Kbit/s are inferior. New Bluetooth versions are currently under development that attempt to eliminate the latter drawback. V1.2 allows rates of up to 3 Mbit/s, V2.0 of up to 12 Mbit/s (Ailisto et al. 2003).
- High rate W-PANs per standard IEEE 802.15 TG3, launched in 2003, use higher power devices (8 dBm) than regular Bluetooth equipment (0 dBm) to transmit data at a rate of up to 55 Mbit/s and over a range of up to 55 m (Ailisto et al. 2003). This technology is, therefore, an attractive alternative to W-LAN, especially considering the comparatively lower cost.
- Low power W-PANs per standard IEEE 802.15 TG4 are particularly useful for handheld devices since energy consumption for data transmission purposes, and costs, are extremely low. The range of operation of up to 75 m is higher than current Bluetooth applications, but the data transfer rate of 250 Kbit/s is lower (Ailisto et al. 2003).
- Wireless body area networks (BANs) interlink various wearable devices, such as wireless data glasses, earpieces, microphones, and sensors, and can connect them to outside networks. BANs are often used for medical applications but also in work-related fields, for example, to provide production operators with instructions that are adapted to the respective work situation. BANs usually consist of a central network unit, which connects the devices and which can provide an interface to further networks outside the BAN, for example, via Bluetooth. Advantages of BANs versus W-PANs are the short range and the resulting lower risk of tapping and interference, as well as low frequency operation, which leads to lower system complexity. Technologies used for wireless BANs include magnetic, capacitive, low-power far-field and infrared connections, while non-wireless BANs use wires or conductive fabrics (Ailisto et al. 2003).
- Radio frequency identification (RFID) encompasses wireless identification through radio transmission. RFID systems comprise a read/write station and active (with own power source) or passive (power supplied by the read/write station) transponders (transmitter / responder), and can be used in a variety of applications. Traditional examples include protection against theft, access control, and billing. The range of possible applications is much greater: RFID systems can be used for material tracking in manufacturing and logistics, for cash register applications in stores as an alternative to barcode scanning, or for localizing items or persons.
As indicated earlier, the mere existence of wireless technology does not suffice to promote ubiquitous communication and computing. Network integration and administration must be made easier and network security guaranteed. To combine computers and networks efficiently and effectively, it is crucial that they can communicate without need for data conversion or translation. This ability is referred to as network interoperability and is imperative for the success of AmI. Companies engaged in AmI research are, therefore, making efforts to agree on communication standards that will ensure compatibility of different objects in the network (Ailisto et al. 2003).
Network administration is facilitated by minimizing the effort required for setting up networks. The introduction of mobile ad hoc networks (MANETs) is an important step in this direction. A MANET uses the wireless technologies described in the list above but is more flexible than conventional networks, since the routers are included in the mobile nodes instead of being fixed and have the ability to configure themselves. This provides the network with great flexibility due to its ability to adapt automatically to a changing network environment (Corson and Macker 1999).
User adaptive interfaces, the third integral part of AmI, are also referred to as "Intelligent social user interfaces" (ISUIs) (van Loenen 2003). These interfaces go beyond the traditional keyboard and mouse to improve human interaction with technology by making it more intuitive, efficient, and secure. They allow the computer to know and sense far more about a person, the situation the person is in, the environment, and related objects than traditional interfaces can.
ISUIs encompass interfaces that create a perceptive computer environment rather than one that relies solely on active and comprehensive user input. ISUIs can be grouped into five categories:
- Visual recognition (e.g. face, 3D gesture, and location) and output
- Sound recognition (e.g. speech, melody) and output
- Scent recognition and output
- Tactile recognition and output
- Other sensor technologies
Traditional user interfaces like PC-controlled touch screens in a company environment and user interfaces in portable units such as PDAs or cellular phones can also become ISUIs. The key to an ISUI is the ease of use, in this case the ability to personalize and adapt automatically to particular user behavior patterns (profiling) and different situations (context awareness) by means of intelligent algorithms. In many cases, different ISUIs, such as voice recognition and touch screen, are combined to form multi-modal interfaces (Ailisto et al. 2003).
With increasing amounts of information being transferred across networks, greater concern arises regarding security and privacy, especially in the light of recent reports on intrusion by viruses and worms, which demonstrate the vulnerability of network technology. A weak spot in networks regarding privacy has been password queries. People with infected machines can be 'watched' by others while typing in passwords, use passwords that are too simple, or use passwords that are too easily relatable to the person, such as names of children, pets, and the like. ISUIs make network usage more secure as the interfaces can identify users automatically by, for example, face or voice recognition instead of requesting a password.
Yet, there are still risks of intrusion at the point of identification to the network. To be protected, proxy firewalls, stateful inspection firewalls or intrusion detection systems must be put in place. Proxies offer the highest level of security, since the actual message does not pass through the firewall. Instead, the proxy application converts the message into a proxy outside the firewall before sending it inside. The disadvantage of a proxy firewall is the high computational effort required of the system, which slows data processing. Stateful inspection firewalls are superior in this respect since they only examine in- and out-flowing data and grant passage through the firewall if the data complies with specified security requirements. This type of firewall is, however, considered less secure than proxies since it allows the actual data through the firewall (Laudon and Laudon 2004). Intrusion detection systems are recommended but should only be seen as a supplement to firewalls as they only detect intrusion after the fact and when potential damage has been done.
It is important for the individual computer in a network to be sure that a message actually comes from the source it is believed to come from. Authentication technologies can ensure this, for example, by means of digital signatures, which ascertain the source as well as the content of a data packet. Finally, to protect critical data, encryption technologies are used which provide only the sender and the selected recipient of a message with the ability to decipher it.
A young mother is on her way home, driving together with her 8-month old daughter who is sleeping in her child seat on the passenger side of the car. The infant is protected by an intelligent system called SBE 2 against airbag deployment, which could be fatal in the case of an accident. SBE 2 detects when there is a child seat on the passenger seat instead of a person and automatically disables the airbag (Lu et al. 2001). Arriving home, a surveillance camera recognizes the young mother, automatically disables the alarm, unlocks the front door as she approaches it and turns on the lights to a level of brightness that the home control system has learned she likes. After dropping off her daughter, the young mother gets ready for grocery shopping. The intelligent refrigerator has studied the family's food consumption over time and knows their preferences as well as what has been consumed since the last time she went shopping. This information has been recorded by an internal tracking system and wireless communication with the intelligent kitchen cabinets. Based on this information, the refrigerator automatically composes a shopping list, retrieves quotations for the items on the list from five different supermarkets in the neighborhood through an Internet link, sends an order to the one with the lowest offer and directs the young mother there. When arriving at the supermarket, the shopping cart has already been filled with the items on her shopping list. Spontaneously, she decides to add three more items to her cart and walks to the check-out. Instead of putting the goods on a belt, the entire cart gets checked out simply by running it past an RFID transponder that detects all items in the cart at once and sends that information to the cash register for processing. What sounds like a science fiction story is an illustration of possibilities AmI can offer people in their private lives and of the main driving forces towards AmI for home use:
- cost savings
- time savings
If companies succeed in offering AmI technology at a price that people are willing and able to pay for the associated benefits, AmI can turn into an entirely new market. More companies are investing considerable sums on research and development of AmI in anticipation of market expansion. For example, Philips has a facility in the Netherlands called HomeLab, which is specifically designed as a development and test site for in-home AmI technology. Here, technologies like Easy Access are emerging. Easy Access recognizes a hook line from somebody humming, automatically compares it with a song database and plays the song on the room's stereo equipment (MagalhÃ£es 2002). Philips' goal is to create a "perceptive home environment", which is able to identify and locate the people in it as well as determine their intentions, to ultimately provide them with the best service possible (van Loenen 2003).
Electrolux and Ericsson built 59 smart condominiums in Stockholm, as part of the alliance's e2 Home project. It was officially unveiled in February 2002, when the first buyers moved in. Inhabitants of these condominiums are now enjoying many of the benefits that modern AmI technology can provide when implemented. The following are some possibilities provided through use of a touch screen terminal located in the kitchen:
- Security: a front door security camera has been installed to permit easy identification of visitors.
- Convenience: the ability to perform availability checks and bookings of common areas such as laundry room and sauna without having to leave the apartment.
- Time saving: home delivery of items that can be placed in smart delivery boxes located outside the door.
Representatives of the e2 Home project report that these new
facilities have enjoyed significant interest from
The Georgia Institute of Technology has developed a 5040-square-foot "Aware home" used as a laboratory of AmI development. Various products have been tested, providing valuable insight into the scope of applications that are available with AmI. Examples are the digital Family Portrait and the Gesture Pendant. Elderly persons are often a source of great concern for their families, especially if they are separated by a large distance. The Family Portrait is unique device because it looks like a regularly framed picture, but its image is updated daily to reflect the general wellness of its subject. If the person in the picture is sick and inactive, the picture will capture this appearance in much the same way that seeing a person in real-life would. The Gesture Pendant helps eliminate the stifling number of remote controls prevalent in most of homes today. Instead, simple hand gestures control multiple devices, providing convenience and minimizing technological clutter.
Besides the positive value that AmI offers in the home environment, there are also critical points that require careful consideration before launching AmI technology in the market: protection of privacy, costs, minimum network scope. AmI systems must protect the privacy of the users. This is likely to be the main concern of customers when making a purchasing decision. For this reason, marketing needs to point out the security advantages AmI can offer, while R&D needs to continue improving network protection against intrusion to improve security reputation of technology.
In general, the cost of AmI technology must be at such a level that the price for an AmI system does not outweigh the perceived benefits to the user. AmI technology in the home environment needs to reach a critical mass. Going back to the example of the young mother and child, it becomes clear that one intelligent device alone has little value or impact. The key to success for AmI is the interaction between different computers in the household and their cooperation with outside networks. This requires considerable investment on the part of the users, and only a limited proportion of society will be available to afford this. To recover the high R&D investment costs, companies should first introduce AmI in the luxury segment, where higher profit margins can be attained and a higher demand for costly, sophisticated equipment is expected.
The introduction of AmI in a home environment will have an impact on personal lives in several ways. The time gained will allow people to spend more time with their family and friends. Convenience, money and time savings, security, safety and entertainment all reduce stress leading to an overall higher quality of life. However, the ability to prepare or complete more and more everyday tasks such as shopping or banking at home potentially leads to reduced face-to-face interaction between people or, at least, to selective interaction restricted to mainly family and friends.
The current phase of AmI/pervasive computing, in which computers are already being embedded in many devices, has begun to affect our everyday lives in ways we do not even notice:
- computing is spread throughout the environment
- users are mobile
- information appliances are becoming increasingly available
- communication is made easier-between individuals, between individuals and things, and between things
Bio-sensing allows devices to not only be able to sense the presence of a user for entertainment and medical reasons, but also to be able to sense the user's needs and goals to enhance person-to-person communication. Organizations are exploring ways to incorporate gaze tracking, emotion detection, speech recognition, and gesture recognition in a "smart" computer, that in the future will often be invisible, with an intuitive user interface (Ark and Selker 1999).
AmI in an intelligent home environment is sensitive, personalized, adaptive, anticipatory and responsive to people. As envisioned by developers, Philips Electronics and Massachusetts Institute of Technology (MIT), ambient intelligence is a marriage between the technologies of ubiquitous computing and social user interfaces.
At the front-end of an AmI system are a variety of tiny devices that can hear, see, or feel an end-user's presence. At the back-end, wireless-based networked systems make sense of these data, identifying the end-user and understanding his/her needs (Ribauda 2003). Wireless digital assistants, network-attached refrigerators, and smart houses are examples of pervasive or ambient computing. For example, think about a "virtual house" that updates its contents whenever you buy merchandise on the Net or in person, and that you can walk around with the aid of a virtual reality headset. IBM's Pervasive Computing Lab, MIT's Media Laboratory, Accenture's Technology Labs and Microsoft's Hardware Devices Group are some of the organizations working with AmI/pervasive computing, based on trends in software, hardware, and networking.
Philips invests approximately $3.25 billion in research and development at its design headquarters to help realize its vision of ambient intelligence in which billions of tiny processors embedded in furniture, walls, and clothes will communicate wirelessly with one another and manage various domestic tasks. For example, it is developing Pogo, a jumble of tools to encourage 4-to-8-year-olds in the art of storytelling. A product called Nebula projects scenery, an alarm clock, and games on to a bedroom ceiling. Using HomeLab and Easy Access, Cappellini-designed beds, couches, and chairs have loud-speakers, projectors, and Web screens integrated into headboards and armrests. The bathroom SmartMirror turns out to be a TV. Ambient-intelligent homes hav been likened to an old English butler: able to make decisions on the user's behalf (Wylie 2003a, Wylie 2003b).
According to Philips, the best way to get started is to study "the physical, social and cultural context in which technology will be used and its implications on daily life". The context here is the domicile. By design, HomeLab is set up to allow researchers and designers to work in concert with end-users "to realize a shared and tangible vision" of future in-home electronic systems. MIT's Rodney Brooks said of the HomeLab project: "Only through living with our technologies can we discover which ones really improve our lives and which ones only sound good as proposals". Since observation is a key element at this stage, HomeLab's audio- and video-based control system both collects and analyzes the data provided by volunteers: the full range of human activity, including postures, facial expressions and social interactions. "By exploring people's cultural expectations with respect to functions, forms and behavior," states Stefano Marzano, CEO Philips Design, "we can ensure that Ambient Intelligence really does improve people's quality of life experience." The target date for true ambient living according to Philips is 2020 (Anon. 2002, van Loenen 2003).
A brand of high-end kitchen appliances, sold in Italy, can regulate their combined consumption, and so keep the consumer from incurring fees for peak power use. In addition to power and networking, designers of these future systems will need to make them aware of their user's identity and location. In other words, not only will devices be pervasive, these devices will have to adjust to human users switching modes during the course of the day, i.e. "use a PDA, move to the car, then back to the office", without having to restart their work or connect to different back-ends. Intermediary transcoding technologies enable devices to communicate with the network, and one information network to communicate with another (Booker 1999).
The next step in the evolution of computing involves the move toward ubiquitous computing, in which computers will be embedded in natural movements and interactions with environments, both physical and social. Ubiquitous computing will help organize and mediate social interactions wherever and whenever these situations might occur. Lyytinen and Yoo (2002) predict that during the next five to ten years, ubiquitous computing will come of age and the challenge of developing ubiquitous services will shift from demonstrating the basic concept to integrating it into the existing computing infrastructure and building widely innovative mass-scale applications that will continue the computing evolution. The main challenges in ubiquitous computing originate from integrating large-scale mobility with pervasive computing functionality. In addition, Ribauda (2003) states that the key technical hurdles are making computers see, hear, speak and understand language since ambient intelligence relies on technologies that are far from fully developed, with no agreed-upon standard yet for operating systems. The size of the potential market for applications, especially in the home, is far from clear.
The vision of a future filled with smart and interacting everyday objects offers a whole range of fascinating possibilities. For example, parents will no longer lose track of their children, even in the busiest of crowds, when location sensors and communications modules are sewn into their clothes. Similar devices attached to timetables and signposts could guide blind people in unknown environments by "talking" to them via a wireless headset. Tiny communicating computers could also play a valuable role in protecting the environment; for example, sensors the size of dust particles that detect the dispersion of oil spills or forest fires. Another interesting possibility is that of linking any sort of information to everyday objects, allowing future washing machines to query our dirty clothes for washing instructions.(Bohn et al. 2004) While personal gadgetry in the form of smartphones and Internet fridges continue to bedazzle the press, industry has quietly begun setting its sights on the enormous business potential that technologies such as wireless sensors, RFID tags, and positioning systems have to offer. Analysts have termed this the "real-time economy" or the "now-economy" (Siegele 2002).
PriceWaterhouseCooper's (PwC) forecast of major trends in IT infrastructure over the next three years focuses on grid computing, computing as a utility, Internet protocol (IP) dial tone and pervasive computing. PwC's forecasts on pervasive computing envision IT as a universal resource that will eventually become an invisible part of daily life. Its realization, however, will require advances in user interfaces, system software, security and pervasive networks (Domingo 2002).
AmI offers enormous benefits and is expected to have a bright future in two key potential markets:
- Home users interested in saving time and money, higher convenience, security, and safety as well as entertainment.
- Organizations pursuing profit maximization through higher efficiency, effectiveness, security, and safety.
The stumbling blocks that might hinder the widespread adoption of AmI in the home environment are costs and risk of intrusion. In the business field, potential employee resistance, legal and ethical restrictions, and risks associated with high system complexity are additional major hurdles that have to be overcome before AmI can be successfully implemented. The US National Institute of Standards and Technology is working on an open-source, pervasive computing standard called Smart Flow to address the underlying problem of connecting a variety of devices, systems and sensors that make up a multi-modal environment (Thibodeau 2003). In addition, computer scientists are creating standards that will enable computers and people to interact, regardless of their location. Pervasive computing utilizes multi-modal interfaces, and that means developing systems that can recognize voice and gestures - systems that perceive their end users.
Research must, therefore, focus on developing user-friendly low-cost solutions with a high level of network security. Managers of the various companies intending to produce and sell AmI technology must agree on common networking standards, which are a major factor determining future success or failure. Managers intending to employ AmI in their companies must ensure that the expected benefits exceed the cost of implementation and that the organization fits the technology, which will in many cases require structural changes. Individuals and organizations will be affected by AmI in various ways and it is the end-user's responsibility to gain the greatest benefits from AmI while preventing or minimizing its potential negative effects as far as possible.
This paper is dedicated to late Rob Kling, a pioneer in social informatics studies who strived for over 30 years to make social issues central to discussions about computing and information systems.
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