Direct comparison of psychological evaluation between virtual and real humanoids: Personal space and subjective impressions

The aim of this study was to compare psychological evaluations of a robot constructed using a virtual reality (VR) system (VR robot) with a real robot. The same design was used for both the VR and real robot in order to make a direct comparison. For the psychological evaluation, we measured behavioral reactions (the amount of personal space the participants desired between themselves and the robot) and subjective impressions (from a psychological scale). The psychological scale included six dimensions that are typically used to evaluate a humanoid: utility, clumsiness of motion, possibility of communication, controllability, vulnerability, and objective hardness. Sixty-one participants observed both the VR and real robots walking toward them and reported their level of desired personal space. Next, the participants evaluated their psychological impressions of the robots. The results indicated no significant difference in the level of desired personal space between the situations with the real and VR robots. However, regarding the psychological dimensions, participants reported higher scores for utility and the possibility of communication, and lower scores for controllability for the real robot as compared with the VR robot. The usability of a VR robot is discussed.