"Are You Sad, Cozmo?"

This paper explores how humans interpret displays of emotion produced by a social robot in real world situated interaction. Taking a multimodal conversation analytic approach, we analyze video data of families interacting with a Cozmo robot in their homes. Focusing on one happy and one sad robot animation, we study, on a turn-by-turn basis, how participants respond to audible and visible robot behavior designed to display emotion. We show how emotion animations are consequential for interactional progressivity: While displays of happiness typically move the interaction forward, displays of sadness regularly lead to a reconsideration of previous actions by humans. Furthermore, in making sense of the robot animations people may move beyond the designer's reported intentions, actually broadening the opportunities for their subsequent engagement. We discuss how sadness functions as an interactional "rewind button" and how the inherent vagueness of emotion displays can be deployed in design.