Communicating simulated emotional states of robots by expressive movements

This research focuses on the non-verbal emotional communication of a non-android robotic arm used for Human Robot Interaction (HRI). It investigates whether products, by moving in a life-like way, can communicate their emotions and intentions to humans or not. The research focuses mainly on the mechanoid robot (IGUS Robolink) whether it is able to communicate its emotions to the user or not. It further inspects about the motion parameters that are important to change the behaviour of mechanoid robot used.
In this study, a relationship is developed between the motion of the robot and the perceived emotion. The validity of the perceived emotion by the user is later checked using three different emotional models: Russell’s circumplex model of affect, Tellegen-Watson-Clark model and PAD scale. The motion characteristics such as velocity and acceleration are changed systematically to observe the change in the perception of affect caused by the robotic motion. The perceived affect is then marked by the user on all three emotional behaviour models.
The novelty of the research lies in two facts: Firstly the robotic embodiment used does not have any anthropomorphic or zoomorphic features. Secondly the embodiment is programmed to adopt the smooth human motion profile unlike traditional trapezoidal motion used in industrial robots.
From the results produced it can be concluded that the selected motion parameters of velocity and acceleration are linked with the changed of perceived emotions. The emotions at low values of motion parameters are perceived as sad and unhappy. As the values for motion parameters are increased the perceived emotion changes from sad to happy and then to excited. Moreover the validity of perceived emotions is proved as the emotion marked by the user is same on all the three scales, also confirming the reliability of all the three emotional scale models. Another major finding of this research is that mechanoid robots are also able to communicate their emotions to the user successfully. These findings for Human-Robot interaction on user’s perception of emotions are important if robots are to co-exist with humans in various environments, such as co-workers in industry or care-workers in domestic settings.