  Cable-Driven Parallel Robots (CDPRs) offer high payload capacities, large
translational workspace and high dynamic performances. The rigid base frame of
the CDPR is connected in parallel to the moving platform using cables. However,
their orientation workspace is usually limited due to cable/cable and
cable/moving platform collisions. This paper deals with the design, modelling
and prototyping of a hybrid robot. This robot, which is composed of a CDPR
mounted in series with a Parallel Spherical Wrist (PSW), has both a large
translational workspace and an unlimited orientation workspace. It should be
noted that the six degrees of freedom (DOF) motions of the moving platform of
the CDPR, namely, the base of the PSW, and the three-DOF motion of the PSW are
actuated by means of eight actuators fixed to the base. As a consequence, the
overall system is underactuated and its total mass and inertia in motion is
reduced.
