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.