Wearable Computing

Desktop interfaces are inappropriate when a user is on-the-go. They require significant manual attention to control a mouse and significant visual attention to track the pointer on the screen. Instead, on-the-go interfaces might use gross gestures and key verbal phrases for input and audio, bold graphics or haptics for feedback. A notable interface problem is text entry. While speech recognition has improved significantly, it is inappropriate in meetings and many other social situations.Mini-QWERTY keyboards, such as the Blackberry, and virtual keyboards require significant hand-eye coordination. Chording input systems such as the Twiddler and the Chorder shown here are fast and best used without visual attention, but they require training. The Half Keyboard employs a more familiar, flat, desktop QWERTY keyboard layout for touch-typing with one hand, but a user chords with the spacebar to achieve the full alphabet.

In the late 1980s and early 1990s, the companies VPL Research and Virtual Research sparked popular imagination with virtual reality (VR) helmets. Unlike wearable computing displays that seek to augment the user’s experience in the everyday world, VR displays attempt to remove the user from reality, enclosing the user in high-fidelity, computer-controlled worlds. Beyond introducing the concept of a head-mounted display (HMD) to the public, these systems also helped focus attention on creating small displays and optics suitable for wearing.Immersive systems feature large field-of-view displays, resulting in heavy headsets that are comfortable only for limited periods of time. These binocular systems sometimes have difficulty creating convincing illusions of 3D environments because only some depth cues can be simulated readily in a headset. Binocular disparity is a strong depth cue, and it may cause considerable conflict with other depth cues such as focus or vergence, leading to fatigue or simulator sickness. Early, heavy CRT technology has yielded to LCDs and recently OLEDs.

What use were mobile head-mounted displays to the average consumer before 2008? Very few digital devices provided a way of feeding an image to an external display. In an attempt to reach consumers, head-mounted display (HMD) manufacturers designed lighter-weight headsets intended primarily for watching videos while stationary, such as during a flight, on a train, or at home.When Apple’s video iPod was released in 2005, HMD manufacturers had a popular mobile system with which to interface. These systems avoid the eyestrain of 3D viewing by opting instead for a 2D experience. Mobile video viewers used displays originally designed for camcorder viewfinders or video projectors. Wearable computing academics and makers adopted these viewers and often adapted them for their mobile needs by removing the display for one eye. They used messaging, mobile navigation, restaurant reviews, email and web search on their wearables before smart phones became prevalent in 2008. Today, similar video viewers are often self-contained or wireless, using microSD cards to play stored movies or using WiFi to connect to a video player.

Instead of immersing the user, one-eyed HUDs designed for industrial, military, and medical purposes often provide brief, intermittent assistance while the user is performing another primary task. For example, an anesthesiologist in the operating room may use a HUD to glance at the patient’s vital signs while looking at his face for signs of hypoxia (lack of oxygen). A soldier may refer to a display to determine his location on a map, or a worker in a warehouse may view a diagram showing which part to pick next for an order.These “microinteractions” last a few seconds and require a device that is faster to access than a smartphone, which averages about 20 seconds simply to unlock and navigate. Like the dashboard of a car, a user glances at it and is quickly back to the task at hand. What tasks would consumers desire if they had similarly fast access to a computer?

A handful of makers and academics began designing wearable computers to be used as part of their everyday lives in the early- to mid-1990s. Instead of focused, work-related duties, these devices were used for more personal tasks: email, messaging, music, note-taking, photography, and scheduling. The MIT Wearable Computing Project established a “living lab” where advocates explored a wearable computing lifestyle in a community of users. Collaboration with designers led to wearable computing fashion shows, where the importance of fashion for devices on the body became clear. A community led by Carnegie Mellon University, Georgia Tech, and MIT established wearable computing as its own academic field and encouraged makers to participate.