A study on design and moving behavior of meal partner robots that can perform eating behavior expression

Dining with people improves our lives and brings a lot of benefits. Nonetheless, many people are compelled to eat by themselves due to the current social situation. We believe that robots can be good meal partners. In this paper, we describe the developed meal partner robots called Mamoru'21 and Mamoru'22. The design of these robots is inherited from a robot for watching over elderly people. Based on previous research that robot's eating behavior expression can improve the mealtime experience, they can perform motions that mimic eating and present food images by monitors. In the first experiment, we confirmed the developed robot could improve the co-eating experience compared to a conventional small humanoid robot, and investigated the keywords for preferable hardware design, such as 'smaller than a child.' In the second experiment, we studied the effects of the robot's moving around during mealtime. As a result, no statistically significant negative effects of robot movement during meals were observed in the developed robot's capability. Though this study has some limitations such as shorter experimentation time compared to regular meals, it contributes some insights and knowledge into the behavior and design of meal partner robots.