Mass and Motion in User Experience
All digital realities are simulacra. In code, there is neither mass nor movement. But there is the appearance of both. Whenever a file shifts across a desktop or a cursor flits over the screen, its movement and interactions with other objects imply classical mechanics. But this appearance is only a convenient fiction that allow us to navigate a graphical user interface. The same is true of websites, apps, games and virtual reality. The user has the sense of dealing with objects that move in space, yet both the objects and the space are artificial.
Within today’s digital environments, movement is two dimensional and mechanistic, yet intuitive. Easing animations create the appearance that an object has mass and is responding to force and friction. The convention when applying these animations is to approximate the typical movement of objects in the real world according to Newtonian physics. Haptic technologies encourage our belief in this fiction. The artificially constructed movement of objects around the desktop is so familiar at this point, that we don’t even question it. It is as expected as gravity.
To some purists, the very idea of three-dimensional space in the digital sphere is inherently “skeumorphic.” Skeumorphism refers to design, especially digital design, that makes use of anachronistic decorative elements from the physical world that are no longer necessary in applications.
In the past, Apple was on the receiving end of criticism for their supposedly skeumorphic design. While I agree that some of Apple’s visual design was flawed, their approach to the fiction of mass and movement in their interfaces has been quite revolutionary. iOS and OS X Lion-enabled devices began to introduce new principles of mass and motion to digital design. Using these apple devices, objects slide across the screen, like a puck on an air hockey table. There is a clear sense of inertia, momentum and friction. But the physics of their constructed reality no longer completely resembles that of the physical world. In fact, there were even reports of users experiencing motion sickness because of the animations in iOS 6.
The explosion of virtual reality and augmented reality technology adds urgency to the question of mass and motion in user experience. Already virtual reality offers fictional experiences like floating in outer space or swimming through the ocean. In both cases, the question of mass and motion are solved by making the user weightless in the environment. But gravity isn’t a Boolean. It is not a binary variable that is either present (true) or absent (false).
There is nothing forcing a digital space to mirror reality. It is a useful convention, but it has stunted the development of digital design. These experimental virtual reality experiences are just initial steps on the way to the ultimate goal of a constructed physics that is both original and intuitive — a constructed physics that abandons or subverts Newtonian norms. To be successful, a constructed physics must obey a set of internally consistent rules. If a given object floats, it must always float. If it responds to a force, it must respond in a consistent way. In the Virtual Reality game, Land’s End, the user can be transported to a floating white orb by staring at it. This is an entirely new, game-specific rule of motion. Users are able to quickly master this new system because the experience is consistent. But an inconsistent system would be no system at all.
Computer games have created fictions using mass and motion since the beginning. Punches land with a force that would shatter all the bones in your hand. An impossible jump is rendered easy by the supposed absence of terrestrial gravity. Velocity, acceleration, work, and energy — no Newtonian principle is recognizable in the world of games. Yet games are user experiences in which people willingly immerse themselves for days at a time. Perhaps the fictional element in the game allows us, as designers, to dream bigger and break more rules.
When it comes to apps and websites, we quantify clicks-to-purchase and concern ourselves with the placement of buttons. It is worth remembering that these digital experiences are also just fictions. If we’re making it all up anyway, why not have a little more fun with the realities we construct. Virtual reality and augmented reality should open us up to these possibilities. Part of appeal of any constructed reality is the ability to extend our experience beyond the mundane. We have unrealized options in our digital interfaces. Mass and motion can be manipulated just like color, shape, and texture. In the end, we should choose our fictions and make them beautiful.
