Joint movement in the human body happens according to the principle of
as the result of pairs of opposing muscles combining their tensions.
Rather than joint movement, could this combined tension
form a basis for the control of musical sound?
The answer is yes:
We can apply a force wave to the fingertip,
and then extract a scalar degree of freedom (DOF)
tracking finger tensing.
it is possible to then
implement tensing control
that occurs simultaneously with, but separately of,
fingertip control based on up/down movement.
(and, more precisely:
, starting at p.137)
demonstrated in a video here