Defining physical interaction

Chris Crawford defines interaction as “a cyclic process in which two actors alternatively listen, think, and speak.” I think that that definition works well for physical interaction, except that I’d replace the terms “listen” and “speak” with “sense” and “respond”, respectively. Although Crawford uses “listen” and “speak” metaphorically, I think that “sense” and “respond” are a little clearer because they suggest a wide variety of inputs and outputs that translate physical phenomena into analog/digital electical signals and vice versa.

Some examples of physical sensing and responding:

Sensing

• Pressure
• Temperature
• Sound
• Light
• Distance (Ultrasound)
• Speed
• Acceleration
• Orientation
• Stretching
• Moisture

Responding

• Light
• Sound
• Movement
• Heat
• Cold
• Pressure
• Vibration
• Texture

What makes for good physical interaction?

I think that Crawford’s thoughts about “high” vs. “low” interactivity are on point here. It’s not enough to just listen, think, and respond - each step has to be done well. Good physical interaction requires a work or piece of technology to:

1. Sense accurately
2. Process what it senses in an interesting or non-trivial way
3. Respond in a way that is comprehensible and communicates meaning

Bret Victor’s comments about moving beyond visual interfaces are also relevant here. Good physical interaction should try to use other human senses as well, such as texture, temperature, hearing, etc. Good physical interaction should be, well, physical.

Examples of non-interactive digital technology

One of my favorite works that involves digital technology that would not be considered interactive is Julien Maire’s Digit, a performance piece that makes use of tiny, hidden printers to create the illusion that the artist is producing printed text simply by sliding his finger across a piece of paper. The printer system isn’t really interactive according to the definition above; it’s more of a tool that translates the artist’s movement into text.

Jürg Lehni’s drawing machines (and most drawing machines in general) are also examples of non-interactive digital technology. They translate images or text into physical motion - communication is one-way from human to machine.

The Empty Space

Peter Brook’s main point in “The Deadly Theatre” is that theatre becomes stale and boring as a result of repetition, of leaning too heavily on tradition and outdated conventions. In order to create work that is relevant, directors, actors, composers, and designers must continuously ask themselves fundamental questions: why is a particular work being performed, what is the intention that they are trying to communicate with their artistic decisions, why even work within the medium of theatre in the first place?

I think that we as new media artists, interaction designers, creative technologists, or whatever you want to call it, also need to ask ourselves these kinds of questions about our work. “What function can it have? What could it serve? What could it explore? What are its special properties?”

In “The Immediate Theatre”, Brook argues that a designer who works in the context of live performance should continuously work with directors and performers to update their designs as the staging and direction of the performance evolves. Set and prop designs constrain the possibilities for staging and direction, so designers must always be ready to revise their work as the needs of a performance change during rehearsal.

I found Brook’s thoughts on improvision in this chapter interesting - the idea that training in improvision is intended to allow performers to avoid falling back on clichés in moments of uncertainty, to push performers towards “something unexpected but true.”

I also like the idea of theatre as a means for an audience to “see more clearly into itself”, that a great performance can leave “a mark of its catharsis.”

Visits to a Small Planet

In Visits to a Small Planet, Elinor Fuchs asks us to assume that everything in a play is intentional, and to ask questions accordingly. What is the physical world of the play like? What is the social structure? How does this world change over time? Who are the characters and how do they relate to this world? What is being asked of the audience?

As designers, how can the visuals, sets, and props that we create answer these questions? In particular, since we spend a lot of time thinking about interaction design at ITP, how can interactions between performers, the audience, and the set answer these questions?