  Wearable robotics bring the opportunity to augment human capability and
performance, be it through prosthetics, exoskeletons, or supernumerary robotic
limbs. The latter concept allows enhancing human performance and assisting them
in daily tasks. An important research question is, however, whether the use of
such devices can lead to their eventual cognitive embodiment, allowing the user
to adapt to them and use them seamlessly as any other limb of their own. This
paper describes the creation of a platform to investigate this. Our
supernumerary robotic 3rd thumb was created to augment piano playing, allowing
a pianist to press piano keys beyond their natural hand-span; thus leading to
functional augmentation of their skills and the technical feasibility to play
with 11 fingers. The robotic finger employs sensors, motors, and a human
interfacing algorithm to control its movement in real-time. A proof of concept
validation experiment has been conducted to show the effectiveness of the
robotic finger in playing musical pieces on a grand piano, showing that naive
users were able to use it for 11 finger play within a few hours.
