Dynamics of pantograph type manipulators

The kinematics of pantograph type manipulators were studied and found to be very computationally efficient due to the decoupled kinematics of pantograph mechanisms [14]. In this paper, the dynamics of a wrist-partitioned, pantograph type manipulators are studied. Both Lagrange's and an extended D'Alembert's methods are used to derive the equations of motion, in applying the extended D'Alembert's method, a special treatment of the force and moment components in free-body diagrams allows the three dimensional motion of the manipulator to be treated as a two dimensional case. This special treatment also eliminates the need of a simultaneous solution of many equations. The extended D'Alembert's formulation is found to be more computationally efficient than the Lagrange's. Moreover, the inverse dynamics of both methods are found to be more computationally efficient than that of a conventional open-chain manipulator.