Development of a child-oriented social robot for safe and interactive physical interaction

As an important approach to ensure safety and naturalness, compliant motion is already implemented in large-size robots, but it is still an undeveloped area in child-oriented robots as it calls for a lightweight and compact solution compared with large-size robots. In this paper, we proposed the design of a social robot which aims at conducting safe and playful Human-Robot Interaction (HRI), especially with children. We built a teddy bear robot prototype based on hybrid passive-active compliant system which consists of flexible joints as passive part and compliant motion controller as active part. The compliant controller detects external perturbation through motor state variables, therefore force and torque sensors could be omitted to keep overall system compact. Experiments conducted in typical HRI scenarios showed that the hybrid passive-active compliant system enabled our robot to conduct safer and more interactive physical interaction compared with robot under traditional control method.