Programming Interactivity, 2nd Edition

Chapter 7. Physical Input

Interaction design opens new possibilities of interaction between humans and technology. Physical computing is a particular type of interaction design that centers on the interaction between the human body and the computer. All the types of interaction explored in this chapter are driven by physical actions, both the sending of information out into the physical world and the sending of information from the physical world into the digital world. The power of physical interaction is in the connection of a physical action to an abstracted result, be that an auditory or visual result.

Some of the controls explored in this chapter are instantly familiar, such as knobs, buttons, and sliders, and some aren’t so instantly familiar, such as accelerometers and infrared sensors. All the code will be Arduino, and we’ll include diagrams to help you get your components connected to your board.

Interacting with Physical Controls

Human beings are flat perceivers; that is, we perceive the world as a flat 2-D space. This is advantageous, evolutionarily speaking, because it’s a natural limit to the amount of information humans can accept. However, humans are quite skilled at mentally manipulating a series of two-dimensional images into a fully realized three-dimensional space, assembling it piece by piece. To record information, we are accustomed to drawing flat representations, maps and diagrams, with which a three-dimensional mental model can be mentally assembled. The classic ...