Humanoid arm with the integrated serial elastic actuator

This paper proposes the design and development of an integrated serial elastic actuator (SEA) which is used as the elbow joint in the soft humanoid arm. First, requirements of SEA are illustrated. And six different types of elastic elements (e.g. the discoid element, the cylindrical) are analyzed using the design of experiment (DOE) method. And then, a discoid elastic element with larger flexibility is developed. Based on this, an integrated SEA containing the position sensors and the torque sensor is developed. And a 7-degree-of-freedom humanoid arm with joint flexibilities is designed. Finally, experiments of SEA demonstrate the approximation of the stiffness between the desired SEA and the prototype.