Publication

Abstract : In the present work, an attempt is made to develop a position-based motion controller for a revolute-spherical-spherical (RSS) type 6-DOF Stewart parallel manipulator. The platform has six servo motor drive units, and a position controller is developed to achieve a given position. Each drive unit’s horn is connected to the revolute crank, and drive units are fixed to a ground plate. Further, cranks are connected through six different rods by a spherical joint at one end of the rod, and the other end of the rod is connected through the end-effector (upper plate) by a spherical joint. The whole mechanism forms multiple spatially close kinematic loop structures that are moving parallelly during motion. An inverse kinematics-based solution has been utilised for its end-effector’s motion for achieving a given task-space-frame location in order to get joint space outputs for the motion. The joint space output obtained from the IK-based solution is further fed to the developed position-based PID controller to achieve the target.