How interesting you would be interested in the footstep. The
human walk is unique in producing that particular sound heard internally
via the skeleton. Our footstep has the foot hitting the floor with
only a vertical velocity (the horizontal is at or nearly zero). The
foot-bones stop so rapidly that the force on them causes a compression
wave to start there. That wave travels up the skeleton to the skull --
that causes a high G (>1g) jerk on the head. That is what is heard
and vestibularly felt -- that shockwave is passing through the skull.
This is only in the human walk. In human adults it is referred to as
the heel strike transient.
However, the earlier developmental walks (infant and young child),
although mechanically different, will also produce that audible
shockwave.What is interesting to me is this is the same
pattern that occurs with very loud rock-music. The walk produces about
120 bpm of a vestibular jolt (that could produce a VEMP response) that
is also audible, and when rock-music is louder than about 95 dB, it does
the same.
That is not a coincidence that these are only in humans. There are some other human unique behaviors supporting that claim.
If you do a study on the acoustic part of that shockwave, please let me know.