Early application of myoelectric prosthetic hand to children with congenital upper limb deficiency have been shown to be effective in acquiring familiarity with prosthetic hand and promoting movements using both hands. However, a robotic hand for prosthetic hand for infant is required to have a weight and size smaller than that of the infant's hand, also requires skill in the hand. These are in a trade-off relationship with each other. In addition, in order to reduce the cost of prosthetic hand and realize smooth application of prosthetic hand, a robot hand that can be used with a wide range of defects is required. In this study, we proposed a mechanism for a robotic hand of a myoelectric prosthetic hand for infants using a bevel gear and a DC motor. By using this mechanism, we have developed a lightweight and practical robotic hand that can be used with a wide range of defects. In addition, the gripping performance improved by searching for the shape of the finger parts of the robotic hand. Furthermore, we confirmed the effectiveness of the robotic hand by applying the developed robotic hand to infants with congenital upper limb defects.
