  Traditional instrument learning is time-consuming. It begins with learning
music notation and necessitates layers of sophistication and abstraction.
Haptic interfaces open another door to the music world for the vast majority of
beginners when traditional training methods are not effective. However,
existing haptic interfaces can only deal with specially designed pieces with
great restrictions on performance duration and pitch range due to the fact that
not all performance motions could be guided haptically for most instruments.
Our system breaks such restrictions using a semi-haptic interface. For the
first time, the pitch range of the haptically learned pieces goes beyond an
octave (with the fingering motion covers most of the possible choices) and the
duration of learned pieces cover a whole phrase. This significant change leads
to a more realistic instrument learning process. Experiments show that our
semi-haptic interface is effective as long as learners are not "tone deaf."
Using our prototype device, the learning rate is about 30% faster compared to
learning from videos.
