Ja. Carretero et al., Kinematic analysis and optimization of a new three degree-of-freedom spatial parallel manipulator, J MEC DESIG, 122(1), 2000, pp. 17-24
A study of the kinematic characteristics of a three degree-of-freedom (dof)
parallel mechanism is presented The architecture of the mechanism is compr
ised of a mobile platform attached to a base through three identical prisma
tic-revolute-spherical jointed serial linkages. The prismatic joints are co
nsidered to be actuated These prismatic actuators lie on a common plane and
have radial directions of action. The mechanism's inverse displacement sol
ution is obtained. Since the mechanism has only 3 dof, constraint equations
describing the inter-relationship between the six motion coordinates are d
erived. These constraints allow the definition of parasitic motions, i.e.,
motions in the three unspecified motion coordinates. Architecture optimizat
ion of the device is undertaken demonstrating that specific values of desig
n variables allow minimization of parasitic motion. [S1050-0472(00)00101-X]
.