An apparatus augments functionality of a human hand with at least one supernumerary artificial appendage. The apparatus includes a brace configured to be coupled to a human arm, a supernumerary artificial appendage attached to the brace, and sensors configured to be coupled to different parts of a human hand and to detect information about at least one of posture, position, velocity, acceleration, force, and torque of the human hand. The apparatus also includes a processor coupled to the sensors and the supernumerary artificial appendage. The processor determines at least one of posture, position, velocity, acceleration, force, and torque for the supernumerary artificial appendage based on outputs from the sensors, and sends at least one control signal configured to operate the supernumerary artificial appendage according to the determined at least one of posture, position, velocity, acceleration, force, and torque.
