Speech driven trunk motion generating system based on physical constraint

We developed a method to automatically generate humanlike trunk motions (neck and waist motions) of a conversational android from its speech in real time. It is based on a spring-damper dynamical model to simulate a human's trunk movement involved in speech. Differing from the existing methods based on machine learning, our system can easily modulate the motions generated due to speech patterns since the parameters in the model correspond to muscle stiffness. The experimental result showed that the android motions generated by our model could be perceived as more natural and motivate participants to talk with the android more, compared with simple copying of human motions.