happening against a backdrop of microprocessors that are faster, smaller, and more energy-efficient than ever before, powered by super-thin, flexible polymer batteries that withstand tens of thousands of bends. Such phenomenal technological breakthroughs are opening up entirely new design possibilities for HCI, to an extent perhaps not seen since the days of the first GUIs.

Projection/ In this special section, Haptic we attempt to map out a future where these tech-

TUI OUI nologies are commonplace. A future led by disruptive change in the way we will use digital appliances: where the shape of the computing device itself becomes one of the key variables of interactivity. We have invited a number of top researchers in this field to share their ideas on this topic. This section covers three tightly knit themes, which define what we refer to as an Organic User Interface (OUI):

Developments in human-computer interaction are often preceded by breakthroughs in display technologies.

Display

Technology

CRT

LCD

HUD/

3D

E-Ink

Flexible and Kinetic

User

Interface

GUI

Ubicomp and

Context-Aware

VR/AR and

Wearables

This diagram shows how OUI interaction styles might eventually relate to those found in traditional GUIs. In OUIs, simple pointing will be supplanted by multi-touch manipulations. Although menus will still serve a purpose, many functions may be triggered through manipulations of shape. OUIs will take the initiative in user dialogue through active shape-changing behaviors. Finally, OUIs’ superior multi-tasking abilities will be based on the use of multiple displays with different shapes for different purposes. These will appear in the foreground when picked up or rolled out, and they will be put away when no longer needed.

Over the past few years, another quiet revolution has been brewing in some of the fundamental technologies used to create digital computing devices. While still limited in resolution, speed, color, and size, pixels made of electrophoretic ink (E-Ink) and light-emitting polymer technologies, combined with advances in organic thin-film circuit substrates, now allow for displays so thin and flexible they are beginning to resemble paper (see Figure 1). Display manufacturers are beginning to weave textile displays as well, by threading large arrays of tiny LEDs into fabrics and furniture. In parallel to these developments, advances in sensor technologies now allow for input devices to track the position of multiple fingers, twists, pressure, and acceleration on any surface. On the output side, miniature actuating devices, shape memory polymers, multi-layer piezoelectric sand-wiches, and tiny ultrasound motors are beginning to allow for “claytronic” interaction devices, with displays that actively reshape themselves [ 1]. All this is

1. Input Equals Output: Where the display is the input device. The developments of flexible display technologies will result in computer displays that are curved, flexible, or any other form, printed on couches, clothing, credit cards, or paper. How will we interact with displays that come in any shape imaginable? What new interaction principles and visual designs become possible when curved computers are a reality? One thing is clear: current point-and-click interfaces designed for fixed planar coordinate systems, and controlled via some separate special-purpose input device like a mouse or a joystick, will not be adequate. Rather, input in this brave new world of computing will depend on multi-touch gestures and 3D-surface deformations that are performed directly on and with the display surface itself. In future interfaces, input and output design spaces are thus merged: the input device is the output device. We have invited two authors to discuss their work on this