Apparatus and methods for transporter shaft coupling and decoupling to
assure alignment of a user interface with a control shaft through
matching asymmetric cylindrical surfaces and alignment of an upper shaft
segment and a lower shaft segment with ribs meshing with grooves on rings
attached to the upper shaft. A tone confirms proper connection. Alignment
apparatus is protected from damage associated with torques applied to the
control shaft by tab features designed to first give way before other
damage is incurred and from moisture by apparatus that seals the
connection between upper and lower shaft segments. The user is protected
from sudden loss of control by requiring the user interface to execute a
sequence of linear and rotational manipulations during assembly of the
shaft.