The effect of different sets of sensed joints in the solution of the
direct kinematics (DK) of parallel manipulators (PM) is studied here,
for purposes of on-line implementation. We consider the most general
geometry of PM with leg architectures consisting of the generators of
the displacement group, that use prismatic or revolute joints, with a
spherical joint at one end. We derive the sensing conditions under which
linear kinematic models are obtained, and for which the DK can be
written as an overdetermined linear algebraic system. The unknown
position and orientation are either solved directly or decoupled. The
latter is attained via a decoupling equation obtained from the
least-square solution of the algebraic system relative to the position
only.

L. Baron, J. Angeles

Mon Nov 13 10:43:02 EST 1995