Input/Output Force An alysis of Parallel Link Manipulator

This paper proposes a method to evaluate the kinematic structure of parallel link manipulators, based on the output force/torque of the mechanisms. As is well known, the relationship between the actuator force/torque and the output force/torque of manipulators is expressed by a manipulator Jacobian. In the conventional method based on the Jacobian matrix, both force and torque are analyzed simultaneously. However, it is not natural to deal with both force and torque simultaneously, since the force and torque have different dimensions. In this paper, we consider the output force and the output torque independently, and introduce the translatability and the rotatability of the manipulators. The kinematic structure is then analyzed based on the translatability and the rotatability of the manipulators. The translatability and the rotatability depend on the maximum output force and output torque of the manipulators, respectively, for given actuator forces. The proposed method is more natural than the conventional method and is useful for the design of the manipulator kinematic structure. An example illustrates the method.