Robotics is a field of interdisciplinary research, and the development of its relevant disciplines has promoted its rapid progress in recent decades. Exoskeletons and bipeds, which are inspired by humans, have attracted many researchers. Exoskeletons, as the extenders of humans, can enhance a person's strength, power and endurance. They are usually utilized in the medical field to provide assistance for disabled people. Bipeds are capable of assisting humans to do repeatable tasks or to operate tasks in dangerous environments. The significance of studying these two kinds of robots is not only to break through the limitations of human capability, but...