HCI Week 4: Affordances

img_0029-450px

In this week’s class we covered the topic of Affordances. This idea originates from the field of Ecological Psychology and the work of J.J. Gibson. It is best known in HCI circles through Norman’s book ‘The Design of Everyday Things.’ According to Gibson, affordances are:

“The affordances of the environment are what it offers the animal, what it provides or furnishes, either for good or ill” (Gibson, p.127)

An important aspect of the idea is that an affordance describes a potential for action in the environment in relation to a person or animal. This has proven to be a very popular concept in design, perhaps because it deals with everyday aspects of perception and interaction and relates the usability of products to their physical form (in relation to a user) in a fairly straight-forward way.

We discussed in detail the work of Djajadiningrat, who has worked with Gibson’s theories of Ecological Psychology in the field of Industrial Design. In particular, he has developed the notions of ‘Feed-forward’ (that a product should inform the user about the purpose of an action) and “Inherent Feedback” (that a user should experience feedback as a natural consequence of their actions).

Critical Questions

  • The notion of affordances has been used in subtly different ways by different authors.

  • Confusion betwen ‘Affordance’, ‘Convention’, and ‘Constraint’.

  • We cannot really talk about screen-based buttons affording clicking

Practical Task

  • Find a product with some interesting affordances for you.

  • Make an analysis of the different actions that it affords for you. Are these in line with the functions that it performs?

  • Bring it to class (so don’t choose a shopping trolley).

Readings

  • Norman, D., 1999. Affordances, Conventions and Design. Interactions, 6(3), 38-43.

  • Djajadiningrat, T., Overbeeke, K. & Wensveen, S., 2002. But how, Donald, tell us how?: on the creation of meaning in interaction design through feedforward and inherent feedback. In Proceedings of the conference on Designing interactive systems. ACM Press, pp. 285-291.