Research Areas & Projects

Research in the lab is spread across several major areas:

Trustworthy Wireless

Wireless communications are becoming ubiquitous and personal as networked devices such as mobile phones, handheld PCs, cameras, music players, and health monitors are increasingly part of the everyday computing environment. In this setting, it is vital that people can use these devices with confidence and without leaving behind "digital footprints" of their identities and activities that can later compromise them. The Trustworthy Wireless Project, under the direction of Ben Greenstein, aims to eliminate the privacy concerns associated with wireless protocols.

Wireless, mobile devices present a greater security risk than wired networks because wireless transmissions are broadcast to all nearby receivers, and because connectivity via mobile devices spreads user traffic over a wider range of parties. This risk is not addressed by the traditional approach of encrypting messages to ensure their confidentiality, nor by layering end-to-end encryption on applications. This is because the link and network layer designs contain low-level identifiers (e.g., MAC addresses) that often map directly to high-level identifiers (e.g., user names).

The goal of the Trustworthy Wireless project is to discover new methods of privacy protection for the users of mobile devices from the physical layer up and across a range of wireless technologies. To accomplish this, the team measures existing systems such as RFID, 802.11, and WiMax to determine what private information is leaked in common usage and how this maps to user expectations. They are also designing revised protocols that offer stronger protections and expose the state of privacy to their users.

Among other topics, Trustworthy Wireless explores:

tools that monitor transmissions and assess the state of privacy for users, including ways to check implementations online and with little hard-coded knowledge of applications.
encrypted network protocols that scramble all low-level identifiers, including addresses and services names. These are normally be sent in the clear for the system to function, as they fall below or outside of traditional confidentiality and authentication mechanisms.
ways to confine reception and connectivity to user-specified service areas at the physical layer, to enhance privacy, security from outside attack, and capacity.

Everyday Behavioral Monitoring

The Everyday Behavioral Monitoring (EBM) Project seeks to enable wide-scale adoption of technologies that sense, model, and support the user in everyday activities. The project develops unobtrusive wearable devices and algorithms that can discern between activities such as running and climbing stairs, cooking dinner and working on a computer. The machines will even be able to perceive whether the user is engaged in a lively debate or telling a bedtime story. The challenge in this research arises from the inherent "noise" of our environment. The unpredictable variation of our everyday lives becomes an impediment to sensor data collection. By testing their devices in uncontrolled environments, project lead, Beverly Harrison and her colleagues, Sunny Consolvo and Tanzeem Choudhury, are working to build privacy-sensitive applications that can adapt to the broad spectrum of human activity.

The first application to emerge from the project was the UbiFit Garden, which attempts to encourage regular physical activity through the use of on-body sensing, mobile displays, and mobile journaling. With UbiFit Garden, a garden blooms on the screen background of an individual's mobile phone as she performs physical activities throughout the week. At a glance, she can determine if she is having an active or inactive week (by the number of flowers), if she has incorporated variety into her routine (by the types of flowers), and if she has met her goals this week and in recent weeks (by the appearance of large and small butterflies). Physical activities are automatically sensed by a wearable device and manually added and edited through a journal on the mobile phone.

Another arm of the team's research involves the creation of models that can decipher complex social interactions. Collecting speech in situ requires recording conversations in unconstrained and unpredictable settings, both public and private. But obtaining audio data from real-life situations is a tricky ethical and legal issue. To preserve privacy, EBM investigators have embedded privacy protection into the lowest levels of processing. They are developing techniques for interpreting the dynamics of a social encounter without requiring access to the raw data streams. Though the subject matter of the recorded speech is unintelligible to the human ear, it still provides enough data for the software to recognize different types of conversation, reason about the relationships between individuals, and infer the structure of social networks.

Technology for Long-Term Care (TLC)

Long-term care--helping elders with tasks required for day-to-day functioning--is a critical problem in many societies. In the US, the estimated cost of such care in the year 2000 was roughly $275 billion. The population of elders is expected to grow sharply in the next few decades, but the resources available for caring for them are not. Without a significant increase in productivity, many elders are therefore likely to be left without adequate care.

Technology for Long-Term Care (TLC) is a validation project aimed at showing that sensor-based monitoring of elder activity can reduce the cost of care in two ways. First, caregivers may check elders' status remotely and therefore avoid the overhead and intrusion of physical presence. Second, elders themselves may perform day-to-day activities more regularly because the monitoring system reminds them to do so.

TLC has deployed activity recognition technology developed by Intel in 20 elder residences in the Seattle area for three months beginning June 2007. Sensors placed on ten to twenty objects around the home and a bracelet worn by elders report data on object use and body motion to an in-home computer. Machine learning algorithms infer whether the elder is performing one of four classes of activities (ambulation, feeding, personal care and vitamin consumption). Lightweight internet-connected electronic picture frames in elder and caregiver homes report hourly on activities that are performed and also summarize the last five days.

Early response to TLC has been very positive. Elders have reported improved performance of daily activities because TLC displays served as reminders. They and their caregivers have also reported improved interaction and more effective care. The technology has proven easy to use. In particular, subjects have proven quite capable of wearing the bracelet and keeping it charged. Overall levels of satisfaction with the system are high, with the presentation of information on TLC displays coming in for particular praise. TLC installation times are substantially lower than those of previous Intel in-home-monitoring projects, and the team has now simplified installation to the point where it is installable by end-consumers. False-positive rates have been much lower than the commercial state of the art based on infrared motion sensors. TLC subjects have also identified a large number of potential improvements.

TLC is a joint project between Intel Labs, Intel's Digital Health business group and the Veterans Administration in cooperation with three major Seattle home-care providers: Elder Health Northwest, Providence and Swedish.

Wireless Resonant Energy Link

The goal of the WREL project is to cut the last cord---the power cord. Building on principles proposed by MIT physicists in 2006, the WREL team recently lit a 60W lightbulb at a range of several feet and very high efficiency---around 70%. The demonstration received extensive news coverage.

How does it work? A singer can shatter a glass by singing at its natural frequency, at which it absorbs energy efficiently. WREL's efficient energy transfer is based on a similar principle. In the case of WREL, a coil of wire with a natural frequency around 10MHz takes the place of the glass, and a similar coil takes the place of the singer.

The next milestone for the WREL project is to build a rectifying circuit that can convert the RF power to DC power---without upsetting the carefully tuned pair of coils. The lightbulb in the existing demonstration is powered by the high frequency (10MHz) signal. To power a laptop or charge a battery, we will need DC power, not a 10MHz AC signal.

While building the prototypes, we are investigating the safety and regulatory issues. It is too early to definitively evaluate the safety or regulatory compliance of any proposed product, as basic properties such as transmitted power levels and safety features have not been set yet.

Organic Photovoltaics

Developing photovoltaic technology for widespread use as a renewable energy source is one of the biggest challenges of the century. Although the growth of the photovoltaic market, driven by technology and environmental concern, has been rapidly increasing, solar cells still only contribute less than 0.1% of our electricity needs. The underlying reason is cost and materials scalability.

First generation wafer-based silicon solar technology is limited by polysilicon feedstock and high cost of manufacturing. Second generation thin-film inorganic solar technology is still not cost competitive, and the popular materials used, like Cadmium and Indium, are toxic, expensive, and not scalable to meet global demand. Even with materials and manufacturing cost reduction, the second-generation thin-film industry is affected by the heavy glass substrates required. Future generation organic photovoltaic (OPV) technology has the promise to be the low-cost renewable energy solution. The most attractive potential of OPVs is the capability for high-speed manufacturing in roll-to-roll coating and/or printing production. In addition, OPVs are light-weight, thin, and flexible to significantly reduce balance of systems costs and enable solar cells to be placed anywhere.

Total power conversion efficiency of OPV devices is determined by the selection of materials and morphology of the organic photoactive layer. This project is focused on new materials design for greater solar energy absorption, and on improving device geometry with ordered nano-fabrication of the OPV layer. The device architecture is common to nanowire photovoltaics in that the fundamental tradeoff of optical absorption and charge diffusion lengths inherent to all other PV technologies is eliminated. Ordered nano-engineering of OPV devices ensures the optimum morphology of the organic photoactive layer is fixed during continued device use. The project seeks to increase efficiency, scalability, and stability of OPVs through proper materials design and device engineering.