Parallel manipulators are a form of closed loop linkages and have a wide range of applications. Parallel mechanisms have many advantages over serial manipulator. Higher accuracy, stiffness and increased payload capacity are the characteristics of the parallel manipulator. In spite of many advantages, they have limited workspace and more singularity regions. So, redundant architectures have become popular. However, redundancy leads to infinite solutions for the inverse kinematic problem. The current work addresses this issue of resolving the redundancy of kinematically redundant planar parallel manipulators. First, the conventional non-redundant 3-RPR planar parallel manipulator is presented. Afterwards, the kinematically redundant counterpart 3-PRPR is discussed and actuation redundant 4-RPR has been touched upon briefly. The workspace of redundant and non-redundant parallel manipulators has been obtained. The generalized stiffness matrix has been derived based upon the Jacobin model and the principle of duality between kinematics and statics. A stiffness index has been formulated and the isotropy of stiffness index is used as the criterion for resolving redundancy. Optimum redundant parameters are obtained as a result of the analysis. A CAD model has also been designed to enhance the understanding of the mechanism workability
