Tsai, L. W.In this paper, the theory of reciprocal screws is reviewed. Reciprocal screwsystems associated with some frequently used kinematic pairs and chains aredeveloped. Then, the application of reciprocal screw systems for theJacobian analysis of parallel manipulators is described. The Jacobian andsingular conditions of a six-degree-of-freedom parallel manipulator are analyzed.en-USkinematicsroboticsJacobianscrew theoryparallel manipulatorsIntelligent Control SystemsTechnical Report