Towards a Capability Taxonomy for Autonomous Robots in Affective Human–Robot Interaction

Autonomous robots are increasingly integrated into social contexts, making affective human–robot interaction (HRI) critical for their effectiveness and acceptance. However, existing research remains dispersed across domains and techniques, lacking a unified framework to characterize core robotic capabilities. To address this gap, we adopt a capability-oriented perspective and conduct a comprehensive literature review, through which we propose a structured taxonomy of capabilities for robots in affective HRI. The taxonomy comprises five core dimensions: Perception (recognizing human internal states), Strategy (planning responses based on human states and context), Expression (conveying robot lifelikeness and social presence), Sustainability (maintaining effective and reliable operation over time), and Ethics (ensuring behavior within ethical constraints). By organizing diverse research efforts into a structured framework, this taxonomy provides a systematic foundation for designing socially competent robots and guiding future research.