Mastering human-robot interaction control techniques using Chinese Tai Chi Chuan: Mutual learning, intention detection, impedance adaptation, and force borrowing

Physical human-robot interaction (pHRI) has become an important research topic in recent years. It involves close physical body contact between human and robots, which is a very critical technology to enable human-robot symbiosis for our future society. An illustrative example is the development of wearable robots [1], where the wearer can extend or enhance functionalities of his limbs. Since wearable robots are worn in parallel and moving synchronously with the human body, human-in-the-loop control plays an important role. Human and robot are no longer two separate entities that make their own decisions. In contrast, they jointly react to the world according to their mutual behaviors and control strategies. Any intelligent decision making of each controller has to consider the other one´s changing dynamics as part of its feedback loop, which is a two-way bilateral control structure.