Effect of Voice Type and Head-Light Color in Social Robots for Different Applications

Abstract

The social robotics field has been growing in prominence. Many developed countries have begun to apply such robots in various fields, such as shopping reception, education, home companion, medical care, and security. However, expectations of social robots have also changed. In addition to performing their specific tasks, social robots are also expected to consider users’ emotional needs. Therefore, scholars have begun to explore robots’ social cues in an effort to enhance their role in society and enable them to provide higher-quality services. This study used the robot s voice type, head-light color, and application field as independent variables to discuss the optimal robot social cues for different applications and to provide a reference for future production and research. Education, shopping reception, and home companion applications were selected as the most common areas employing social robots. According to the vocal fundamental frequencies used in related studies, three voice types were included: male, female, and child. The three values for head-light color, namely warm, neutral, and cold colors, were set according to color temperature theory. The robot social attribute scale, with the addition of an acceptance component, was used to evaluate respondent perceptions. Results revealed that male voices provide users with the highest impression of competence, whereas children s voices have the lowest competence. However, results for the warmth component were completely different: in this aspect, children s voices had the highest evaluations and male voices the lowest. For head-light colors, neutral colors had the highest overall acceptance, the highest competence evaluation, and the lowest discomfort. The neutral color s warmth judgment was the same as that of the warm color, and its competence rating was the same as that of the cold color. For home companion robots, we recommend a child’s voice with neutral colors as the first choice, and a child’s voice with warm color as the second option. Because females rejected male voices, male voices are not recommended in home companion. For education and business, a male voice and neutral colors are the first choice. A female voice is also the second option. In cases with less focus on warmth impression but greater emphasis on competence impression, cold colors could be employed.