An Affordance-based Conceptual Framework for Spatial Behavior of Social Robots Felix Lindner and Carola Eschenbach Abstract Socially aware robots have to coordinate their actions considering the spa- tial requirements of the humans with whom they interact. We propose a general framework based on the notion of affordances that generalizes geometrical accounts to the problem of human-aware placement of robot activities. The framework pro- vides a conceptual instrument to take into account the heterogeneous abilities and affordances of humans, robots, and environmental entities. We discuss how knowl- edge about (socio-)spacial aspects of affordances can be used in various reasoning tasks relevant to human-robot interaction. Applying the notion of a practical reason, socially-aware robots are able to solve the social activity-placement problem. Key words: social robots, spatial behavior, conceptual model, affordances 1 Introduction Gibson (1977) introduced the notion of affordance as the central concept of ecolog- ical psychology. According to him, affordances are the possibilities for actions the environment offers to agents in cases where the abilities of agents and properties of the environment match. For example, chairs afford sitting to humans, stairs af- ford climbing to many humans, but form obstacles for many types of robots and for humans in wheelchairs, and some types of ramps afford climbing to both humans and robots. Both humans and robots also provide affordances to other humans and robots, thereby enabling interaction with other agents. Felix Lindner Albert-Ludwigs-University of Freiburg, Department of Computer Science, Foundations of Artifi- cial Intelligence Group, e-mail: lindner@informatik.uni-freiburg.de Carola Eschenbach University of Hamburg, Department for Informatics, Knowledge and Language Processing Group, e-mail: eschenbach@informatik.uni-hamburg.de 1