Human–robot creative collaboration is often constrained by command–response paradigms that position robots as tools rather than partners. While expressive robotics has shown social values, its role and behaviors in shaping creative partnerships with humans remains underexplored. Therefore, we investigate how robots' expressive behaviors influence co-creative engagement. In a formative study with 5 participants, we identified design insights for users to perceive a robot arm's expressive behaviors. We then implemented these expressive behaviors and conducted a within-subject study with 18 participants, comparing functional-only and expressive conditions in figure drawing tasks. Results showed that expressive behaviors significantly enhanced human-robot collaboration where they shifted from viewing the robot as a tool to a partner with a stronger emotional connection and collaborative satisfaction. Our contributions include empirical evidence of partnership transformation and design insights for facilitating human-robot creative collaboration.
ACM CHI Conference on Human Factors in Computing Systems