Artificial emotion expression for a robot by dynamic color change

We propose a novel method of expressing emotions for a robot by dynamically changing the color luminosity of its body. To identify color and dynamic parameters for representing emotions, we asked subjects to select hue values and frequencies and waveforms of blinking to represent the 24 emotions of Plutchik´s Wheel of Emotions. The results indicate that the hue value represents basic types of emotion, i.e., anger-red, anticipation-amber, joy-yellow, trust-green, fear-violet, surprise-red, sadness-blue, and disgust-purple, and the duration and waveform represent emotion intensity, i.e., a rect-angular waveform with high frequency represents intense emotion. Another experiment validated that emotions of a robot expressed using our model impressed other subjects appropriately.