Beyond R2D2: Designing Multimodal Interaction Behavior for Robot-specific Morphology

Robots are expected to enter the everyday lives of people to entertain, educate, or support them. It is therefore important that people can intuitively understand the behavior of robots. Oftentimes, the behavior of people is used as a model because of its familiarity. However, it is as yet unclear what the best approach is to design interaction behaviors for non-humanoid robots. In this article, we explore two different approaches toward designing behavior for a service robot. The first concerns the commonly used approach of copying human behavior as closely as possible to the robot (human-translated). The second approach was inspired by product design methods. The design of the robot's behavior was optimized for the robot's interaction capabilities and hardware modalities (robot-optimized). To evaluate people's responses to the two behavior sets for a tour guide robot, an online video study (N = 204) and a two-day in-the-wild study (N > 600) were performed. Results showed that participants responded slightly more positive to robot-optimized behavior and paid attention to robot-optimized behavior for longer. However, participants remembered more details when the robot showed human-translated behavior. Together, the studies show that it is sometimes better for non-humanoid robots to have robot-optimized behaviors rather than human-translated behaviors.