Singularity management of 2DOF planar manipulator using coupled kinematics

This paper describes a new 2DOF planar manipulator (PM) using coupled kinematics to manage the singularities. It is designed in order to overcome the singularity configuration of planar manipulators. Manipulators are composed of five rigid links, five revolute joints and two actuators each actuating two of input links coordinated fashion, what we term coupled kinematics. Coupled kinematics is an actuating arrangement. It may be defined as a pair of axial rotations, which are distributed by an actuator at varieties of parameters, which depend transmission ratios of mechanism. Using the geometrical approach, the position of end-effector is obtained. Matching the velocity of end-effector from two branches, the input and output velocities relation can be derived. Considering the coupled kinematics effects, Jacobian matrix is determined. We show that, by mean of proper tuning of the parameters of coupled kinematics, the singularity manifold can be substantially simplified. Finally, note that kinematic coupling can be implemented using mechanical or electronic hardware.