Dynamic analysis of a three-degrees-of-freedom in-parallel actuated manipulator

Despite the voluminous publications on robot dynamics and control, the literature to date is based solely on the serial link manipulators. Little attention has been given to the alternative manipulator design based on the concept of in-parallel actuated mechanism, which is characterized by its excellent rigidity, high strength-to-moving-weight ratio, and relatively simple inverse kinematics. This communication presents the dynamic analysis of a three-degrees-of-freedom in-parallel actuated manipulator. The equations of motion have been formulated in joint space using Lagrangian approach. The analysis provides the solution to predict the forces required to actuate the links so that the manipulator follows a predetermined trajectory. A dynamic simulation program which has been developed illustrates the influence of the link dynamics on the actuating force required. The dynamic analysis provides a basis for future theoretical research to develop the control scheme, for experimental research to estimate the inertia parameters, and for design optimization of the prototype manipulator.