Decoupled Parallel Manipulators Generating S-RS-US Structures: Instantaneous Kinematics and Singularity Analysis

In a previous paper, a family of decoupled parallel manipulators (DPMs) has been identified which generate S-RSUS structures when the actuators are locked. The DPMs of this family refer to sixty-three different architectures with only three limbs and the actuators on or near to the base. This actuator arrangement makes them able to provide the same dynamic performances as fully-parallel manipulators, which have six limbs and a cumbersome coupled kinematics. The position analysis of all these DPMs has been already solved in analytical form. Here, their instantaneous kinematics and singularity analysis are addressed.