Erik Lagerstedt

Perception is a vast subject to study. One way to approach and study it might therefore be to break down the concept into smaller pieces. Specific modes of sensation, mechanisms, phenomena, or contexts might be selected as the proxy or starting point for addressing perception as a whole. Another approach would be to widen the concept, and attempt to study perception through the larger context of which it is a part. I have, in this thesis, attempted the latter strategy, by emphasising an existential perspective, and examine the role and nature of perception through that lens. The larger perspective of broadening the scope does not specifically allow for better answers, but rather different kinds of answers, providing complementary ways of exploring what it means to be an artificial or natural agent, and what consequences that can have for the access to, as well as representation, processing, and communication of information. A broader stance can also facilitate exploration of questions regarding larger perspectives, such as the relation between individual agents, as well as their place in larger structures such as societies and cyber-physical systems. In this thesis I use existential phenomenology to frame the concept of perception, while drawing from theories in biology and psychology. My work has a particular focus on human-robot interaction, a field of study at a fascinating intersection of humans designing, using, and communicating with something human-made, partially human-like, yet distinctly non-human. The work is also applied to some aspects of the traffic domain which, given the increasing interest in self-driving vehicles, is partially another instance of complex and naturalistic human-robot interaction. Ultimately, I argue for a pluralistic and pragmatic approach to the understanding of perception, and its related concepts. To understand a system of agents as they interact, it is not only necessary to acknowledge their respective circumstances, but take serious the idea that none of the agents’ constructed worlds are more or less real, they might only be more or less relevant in relation to specific contexts, perspectives, or needs. Such an approach is particularly relevant when addressing the complexities of the increasingly urgent sustainability challenges.

The term ‘multimodality’ has come to take on several somewhat different meanings depending on the underlying theoretical paradigms and traditions, and the purpose and context of use. The term is closely related to embodiment, which in turn is also used in several different ways. In this paper, we elaborate on this connection and propose that a pragmatic and pluralistic stance is appropriate for multimodality. We further propose a distinction between first and second order effects of multimodality; what is achieved by multiple modalities in isolation and the opportunities that emerge when several modalities are entangled. This highlights questions regarding ways to cluster or interchange different modalities, for example through redundancy or degeneracy. Apart from discussing multimodality with respect to an individual agent, we further look to more distributed agents and situations where social aspects become relevant. In robotics, understanding the various uses and interpretations of these terms can prevent miscommunication when designing robots, as well as increase awareness of the underlying theoretical concepts. Given the complexity of the different ways in which multimodality is relevant in social robotics, this can provide the basis for negotiating appropriate meanings of the term at a case by case basis.