An Application of a 3-RRRS 6 DOF Parallel Manipulator

Abstract

A new drive simulator is designed and fabricated through three legged, 6-DOF RRRS (Revolute- Revolute- Revolute- Spherical) parallel manipulator having three 1-DOF joints which are of revolute type and the middle joint being passive. The three legs are placed equilaterally on the base. Base joint rotates about a vertical axis whereas the other two joints rotate parallel to horizontal plane. The main objective of this drive simulator is to reduce the overall cost of a drive simulator which is done by replacing the conventional drive simulators having linear actuators with ones having rotatory actuators. Conventional drive simulators are 6 legged and each actuator is a linear actuator. The proposed design of drive simulator is having 3 legs which leads to increase in workspace and since prismatic actuators are replaced by rotary actuators the overall cost is also reduced.  For the proposed drive simulator, inverse kinematics model is generated in a closed form way and workspace of the fabricated drive simulator is verified and workspace volume is calculated for all possible orientations and plotted. Kinematic control is done through Arduino based on inverse kinematics model.