A Spatial Parallel Kinematic Manipulator with Nested Kinematic Chains and High Rotational Range

—The paper presents the design and development of a novel five Degree of Freedom (DOF) Parallel Kinematic Manipulator (PKM) which possesses 3 pairs of coplanar limbs with nested kinematic chains. The design employs actuated prismatic joints and passive revolute joints. Universal joints were decoupled into individual revolute joints to achieve a high rotational range of the end effector about two axes. A pair of coplanar limbs exhibited either a Parallelogram (Pa) or an Irregular Quadrilateral (IQ) structure which was dependent on the orientation of the end effector. The PKM, named the 2-R (Pa-IQ) RR, R(Pa-IQ) R manipulator, possesses three translational DOFs, two rotational DOFs and a parasitic rotational DOF. The inverse kinematic analysis was solved by applying the vector method twice. SolidWorks® and MATLAB® simulations were used to validate the inverse kinematic equations. The Monte Carlo method was used to generate the workspace volume. An additive manufactured desktop prototype was developed and used for testing and experimentation.