Free The Design of Future Things by Don Norman Page B

are even more important for the design of future things. When devices are automatic, autonomous, and intelligent, we need perceivable affordances to show us how we might interact with them and, equally importantly, how they might interact with the world. We need affordances that communicate: hence the importance of de Souza’s discussion with me and of her semiotic approach to affordances.
    The power of visual, perceivable affordances is that they guide behavior, and in the best of cases, they do so without theperson’s awareness of the guidance—it just feels natural. This is how we can interact so well with most of the objects around us. They are passive and responsive: they sit there quietly, awaiting our activity. In the case of appliances, such as a television set, we push a button, and the television set changes channels. We walk, turn, push, press, lift, and pull, and something happens. In all these cases, the design challenge is to let us know beforehand what range of operations is possible, what operation we need to perform, and how we go about doing it. During the carrying out of the action, we want to know how it is progressing. Afterward, we want to know what change took place.
    This description pretty much describes all the designed objects with which we interact today, from household appliances to office tools, from computers to older automobiles, from websites and computer applications to complex mechanical devices. The design challenges are large and not always carried out successfully, hence our frustrations with so many everyday objects.
Communicating with Autonomous, Intelligent Devices
    The objects of the future will pose problems that cannot be solved simply by making the affordances visible. Autonomous, intelligent machines pose particular challenges, in part because the communication has to go both ways, from person to machine and from machine to person. How do we communicate back and forth with these machines? To answer this question,let’s look at the wide range of machine+person coupling—an automobile, bicycle, or even a horse—and examine how that machine+person entity communicates with another machine+person entity.
    In chapter 1 , I described my discovery that my description of the symbiotic coupling of horse and rider was a topic of active research by scientists at the National Aeronautics and Space Administration’s (NASA) Langley Research Center in Virginia and the Institut für Verkehrsführung und Fahr in Braunschweig, Germany. Their goal, like mine, is to enhance human-machine interaction.
    When I visited Braunschweig to learn about their research, I also learned more about how to ride a horse. A critically important aspect of both horseback riding and of a driver’s controlling a horse and carriage, Frank Flemisch, the director of the German group explained to me, is the distinction between “loose-rein” and “tight-rein” control. Under tight reins, the rider controls the horse directly, with the tightness communicating this intention to the horse. In loose-rein riding, the horse has more autonomy, allowing the rider to perform other activities or even to sleep. Loose and tight are the extremes on a continuum of control, with various intermediate stages. Moreover, even in tight-rein control, where the rider is in control, the horse can balk or otherwise resist the commands. Similarly, in loose-rein control, the person can still provide some oversight using the reins, verbal commands, pressure from the thighs and legs, and heel kicks.
    An even closer analog of the interaction between horse and driver is that of a wagon or carriage, as in Figure 3.2 . Here, thedriver is not as tightly coupled to the horse as the rider who sits on its back, so this is more similar to the average, nonprofessional driver and a modern automobile. The coupling between horse and driver on the wagon, or driver and automobile, is restricted. Even here, though, the