Review of Dimension Inhomogeneity in Robotics

Numerous robotic indices have been proposed to evaluate the robot performance and for optimal design of robots. However, due to different units in the output and input of the robotic system, most of these indices are not invariant with respect to changes in the dimensional units. In this paper, the problem of dimensional inhomogeneity in robotics is reviewed and described. The main approaches suggested in the literature for solving unit inconsistency are concluded and some details are given. Finally, it is highlighted that the task-oriented performance index should be carefully designed to be physically consistent, dimensional homogeneous, and frame invariant.