JFET_V11_N4_RP5 Harish Mandalaparthy Mohan Rao N. Journal on Future Engineering and Technology 2230 – 7184 11 4 39 47 Parallel Manipulators, Kinematics, Singularity, Workspace, Parasitic Motions All the 3-DOF (Degrees Of Freedom) parallel manipulators with three legs having three joints in each leg (3-PRS,3-PPS,3- PSP, and 3-RPS) are suffering from parasitic motions, and it is not possible to eliminate parasitic motions as they are inherent in their structure. In this present work, a new manipulator with three actuating legs (PSPR), and a passive constraint leg (PU) is proposed. As the actuations and constraints are separated, the constraint leg restricts the moving platform to move in unwanted directions and hence the parasitic motions are eliminated. Therefore, the manipulator is an accurate positioning device. The constituent equations are derived from the architecture of the manipulator. The problem of direct kinematics is solved and demonstrated through a numerical example. The inverse kinematics equations are differentiated with respect to time to obtain Jacobian matrices. Singularity analysis is carried out to identify singular positions. The workspace is represented in 3D space by taking rotation about x-axis as abscissa, rotation about yaxis as ordinate, and translation along z-axis as applicate. May - July 2016 Copyright © 2016 i-manager publications. All rights reserved. i-manager Publications http://www.imanagerpublications.com/Article.aspx?ArticleId=8115