Evaluation and Design of Manipulators Based on a Dynamic Accuracy Index Considering Task-Directions

Some manipulation tasks have directions of end-effector acceleration of a manipulator and directions for which dynamic accuracy is required in the motion. This paper proposes an index (DAIT: Dynamic Accuracy Index for Task-directions) that allows us to evaluate the dynamic accuracy of manipulators considering the task-directions. Firstly, we derive the DAIT. Secondly, we evaluate some postures of a 2-degrees of freedom (DOF) planar manipulator on the basis of some indices that have been proposed (condition number, dynamic manipulability measure and task compatibility) and the DAIT, respectively. Thirdly, we show a manipulator’s design example based on the DAIT. Finally, from the evaluation and design results, we discuss the usefulness of the DAIT in determining the suitable postures of the manipulator for a given task and in designing the suitable manipulators for a given task.