The U.S. patent office has issued a patent filed by Google in 2012. It aims to give robots a personality. It is for Google to simplify communication between robots and humans. In the scenario imagined by Google, the robot will be able to analyze voice of his, possibly to analyze her facial expressions in order to adapt its interaction with him. Google has even imagined a Cloud system to enable them to share these traits on the Cloud.
Source : “Methods and systems for robot personality development”, USPTO, March 31, 2015