Architecting Experience: Five Principles for Interaction Design
We stand at the dawn of a huge shift in the field of interaction design, one defined by the convergence of interactive media and the built environment. We envision a future in which the dynamism of the digital world is embodied in the physical, in which everyday objects have even richer interactivity than today’s smartphones. Tomorrow’s interaction designers will help create the furniture we use, the spaces we live and work in, and the objects we surround ourselves with. As the line between interface and object blurs, this emerging design space needs a new set of design principles.
The following design principles were developed through our practice in both academic and commercial contexts. They guide us when designing for interactivity that enhances and enriches, rather than dictates, human experience.
Combine Physicality + Interactivity
We need to think beyond the traditional graphical user interface, where most of the user’s interaction is confined to a mouse or touch screen. In designing tomorrow’s computers, we can and should incorporate interactivity directly into physical objects and spaces. For example, by using a technology like Swarm—tiny, graspable robots that combine the versatility of a graphical interface with the tactile advantages of physical controls—we can make abstract information tangible. Tangible information has the advantage of form and texture. Furthermore, a tangible interface engages the body and allows for an experience that is far more dynamic than just looking at pixels on a screen.
Create Legible Interactions
Many graphical interfaces are designed to be used by only one person at a time. As interactivity moves beyond screens, it is increasingly important to design systems for use by multiple people. This might mean face-to-face collaboration or play, or it might mean one person is interacting while others watch. In either case, it is important that whoever is watching the interaction is able to follow what is going on: to understand cause and effect, and to surmise the general rules of engagement. We call this interaction legibility.
Legible interactions are instructive. By observing another user demo an interaction, an onlooker will learn how to engage an interface herself. In public spaces, legible interactions also accrue onlookers, causing people to gather.
Key considerations for interaction legibility include:
— I/O Coincidence
Input and output should happen in the same physical location. For example, a touchscreen has I/O coincidence because the display and the touch sensor are located right on top of one another. In contrast, a computer mouse does not, because input happens on a tabletop and output happens on screen. I/O coincidence improves interaction legibility by helping a bystander to focus her attention in one place.
— Immediate Feedback
When a system responds immediately to a user’s actions, it helps onlookers discover and understand the cause-and-effect relationships surrounding those actions.
Interactions are more legible when onlookers can see the same things as those who are actively engaged.
— Body Engagement
When the movement of a person’s body drives an interaction, the interaction is more legible if it is based on larger body movements.
By mapping actions and data onto physical objects that people can touch, move, and manipulate, designers can tap into pre-existing knowledge and social constructs concerning how we share objects and use tools.
Many objects that predate computers embody the above mentioned characteristics. A violin is a good example. When a musician moves her body, drawing a bow across the violin’s strings, sound is emitted. This sound is immediate, and emitted directly from the object that the musician is engaging. The rules governing this interaction are obvious to an audience member. The legibility of a violin player’s interaction with her instrument is a big part of why a musical performance is fun to watch. One gets to see, and begin to understand, the process through which the music is made.
Empower People to Explore
Designers must give people the pleasure of authoring their own experiences. Interactive environments should not dictate a series of step-by-step instructions. Rather, they should sense and respond in a way that encourages the user’s exploration through visual, auditory, or tactile cues. In SenseScape, an installation we designed for Intel’s booth at the Consumer Electronics Show, visitors use their bodies to engage with an aquatic-like environment. Raising an arm causes fish to scatter. Strumming harp strings produces dramatic on-screen ripples and otherworldly seascape sounds. Because these interactions are legible, users feel empowered to experiment and discover a variety of different styles of interaction. While instructions can be appropriate when using a task-specific tool, the best interfaces do not confine the user’s experience within a narrow band of predetermined action. Rather, they encourage and reward exploration.
When we design to enable improvisation, we are allowing for the possibility that interactions with our creations may extend beyond those originally intended. For example, the record turntable was not conceived as a tool for musical improvisation, however, experimental musicians in the 1930s and hip hop DJs in the 1970s used it to create new forms of music.
Systems that enable this sort of improvisation share a few key properties:
— Simplicity of Interaction
A typical turntable supports a few simple interactions. You can play or stop music, switch songs, or switch records. This simplicity makes it easy to mentally unpack any interaction with the turntable into its component parts.
— Immediate Feedback
The sound from a turntable immediately changes in response to the motion of the record, enabling a direct understanding of the cause-and-effect relationships surrounding its operation.
— Ease of Exploration
Because a record is visible and touchable on a turntable while it is playing, one can easily reach in, move the record, and see what happens. There are no mechanisms designed to prevent you from doing something the product’s designer did not envision, thereby allowing for spontaneity.
Interactions we did not originally envision took place in the Create a Chemical Reaction exhibit that we developed for the Museum of Science and Industry. The exhibit allows visitors to explore the elements in the Periodic Table through electronically tagged pucks. We had intended for these pucks to be used in contact with their tabletop surface, however, we noticed people picking the pucks up off of the surface and exchanging them. Family members would pass pucks from hand to hand, away from the tabletop surface, letting each member contribute an atom to help build the collectively desired molecule.
In the end, we are focused on allowing people to reconnect with each other. Technology has developed a reputation for joining us together only in a virtual sense. We have a cultural anxiety that our interpersonal relationships, increasingly mediated through screens, are weakening. The problem isn’t that technology is inherently aligned toward isolation. We must break this assumption, and actively design against it. This may mean exploring interdependent interfaces that cannot work, or cannot work properly, without multiple users. It may mean architecting experiences that allow people to connect within the same physical space, that facilitate interactions between individuals that would otherwise not occur.
As interactive technology permeates more and more of the spaces around us, interdisciplinary collaboration will be a key factor in the quality of experience that this technology produces. Architects, interaction designers, electrical engineers, product designers, software developers, and more will have to work together. Each of us in our respective disciplines should question the way we’ve been looking at things. If the technological constraints of the past are holding us back, we should not be averse to finding and forging a new way forward. There might be different ways of living and working.
We need to collectively reconsider our expectations for what our relationship to technology should be. We cannot simply reproduce the screen-based apps of today if we want to revolutionize the world for tomorrow.