On behalf of my co-authors Marianne Graves Petersen from Aarhus University
and Stijn Ossevoort from Eindhoven University
I present our paper entitled Expressivity in Interaction, a framework for design.
My name is Miguel Bruns
and I work at the Department of Industrial Design at Eindhoven University of Technology.
Our work is particularly inspired by artificial intelligence,
emerging materials and shape-changing interfaces.
Expressivity, expression, expressive behaviour or expressiveness,
are reoccurring terms in HCI and design research.
While many researchers emphasise that interaction should be expressive,
there is little agreement on what the term denotes.
To give a few examples…
Forlizzi and Battarbee discuss how expressive interactions
support the development of a relationship between a user and a system.
Wensveen and colleagues refer to expression as a system’s reaction,
with a diversity of dynamic qualities, reflecting the expression of a user’s action.
Finally, Dalsgaard and colleagues define expressivity as the way in which
people can convey thoughts or feelings towards a system
using multiple, multimodal and nuanced approaches, depending on their competences.
These different perspectives are summarised in this figure, showing the interaction qualities from
a human, artefact and socio-cultural perspective and illustrate the cacophony surrounding the term.
Expressivity has also been prominently used
in the design rationales of various research-through-design projects,
which can serve as a theory nexus.
For example, the Alarm Clock by Stephan Wensveen
enables humans to express their emotions towards the system.
Planks by Anna Vallgårda shows the expressive quality of a computational composite.
Finally, the AEI lamp designed by Philip Ross is illustrative for expressive interaction,
supporting both the expression of emotions through human behaviour
as well as expressive behaviour of the lamp.
We build on the Perspectives Framework by Philip Ross
which provides four perspectives of engagement,
namely Sensory-Motor Activity, Dynamic Form, Social Activity, and
Value in relation to human behaviour and artefact behaviour.
Based on an analysis of various research-through-design cases
the following terms emerged in relation to the perspectives:
Emotion, Freedom of Action, Ambiguity / Subtlety,
Skill Development, Temporal Form, Multimodal Feedback, Action-Perception
and Soci(et)al Context.
To confirm these terms, we conducted a systematic literature review
yielding 29 design cases describing expressivity in interaction.
From these 29 design cases we extracted the authors’ descriptions of their design rationales,
as illustrated in the example of Dancing with Drones. The quotes were categorised
by two of the authors based on the terms found in our first review, which confirmed
that all qualities had been used to a certain extend to describe the expressivity in interaction.
Based on our findings we propose this framework for Expressivity in Interaction.
Expressivity in interaction is achieved by supporting emotional expressivity
and freedom of interaction and through temporal form of the artefact.
The action-perception loops between human and artefact
can have multimodal qualities and allow for subtlety and ambiguity.
Through the interaction between human and artefact a skill can be developed.
The framework was presented in a master course at Industrial Design
and used to design a soft-robotic shape-changing interface.