Design and development of five-fingered hands for a humanoid emotion expression robot

Among social infrastructure technologies, Robot Technology (RT) is expected to play an important role in solving the problems of the aging society. New generations of personal robots are expected to be capable of assisting humans in a variety of contexts and thus of interacting and communicating with them effectively and even in a friendly and natural way. Expressing human-like emotions is an important capability to this aim. The objectives of this work are the design and development of two five-fingered robotic hands for a humanoid upper body able to generate and express emotions. The specific design goals have been grasping and expression of emotions through hand gestures, as a complement to facial expression of emotions. The paper presents the design process of the robotic hands, named RCH-1 (Robocasa Hand No. 1), starting from the requirements deriving from their use in grasping and gestures. The resulting robotic hands are described in detail, together with the hand sensory systems. Experimental trials are then presented, aimed at assessing the hand performance and at validating their effectiveness in grasping and emotion expression, when mounted on the emotion expression humanoid robot WE-4R (Waseda Eye No. 4 Refined).