The 4-RUU PM is a Schönflies motion generator with four identical limb structures and revolute actuators.
Derivation of the constraint equations of the 4-RUU PM by using the Study kinematic mapping.
Operation mode analysis of the 4-RUU PM by decomposing it into two iso-constrained 2-RUU PM.
Analysis of singularities, self-motions, and operation mode changing of the 4-RUU PM and 2-RUU PM.