A Dexterity Measure for the Kinematic Control of Robot Manipulator with Redundancy

Manipulator Performance Measures - A Comprehensive Literature Survey

“…In [6] Chang notes, "a quantitative measure provides us with a rational basis upon which we can, without having to rely on experience and intuition alone, analyze, design, and control the systems". Performance indices or parameters are commonly used metrics in the design, synthesis, task planning, and performance evaluation of robotic manipulators.…”

“…In some robotic research literature the words 'dexterity' and 'manipulability' have been used ambiguously [6], however, in this paper dexterity strictly refers to all possible orientations of the end-effector about a point in the manipulator workspace, and manipulability refers to the ability of the manipulator to move and apply forces in arbitrary directions.…”

“…The manipulability index is equal to zero if the Jacobian is not full rank [61]. Another disadvantage of using the manipulator determinant is that once the Jacobian loses its full rank, it does not distinguish between one type of singularity from the other, as both determinants are zero [6].…”

“…MSV varies more radically near singularities than the other singular values ( [1], [2], [6]). MSV can be seen as an efficient indicator of whether the determinant is close to zero [63], in other words, the MSV is better indicator of closeness to singularities than the manipulability index or the condition number.…”

“…Yoshikawa [71], interpreted the condition number as a measure of directional uniformity of the velocity ellipsoid. The condition number has also been interpreted as a measure of the accuracy with which the manipulator can generate output forces from input torques, and workspace velocity from joint velocity ( [6], [66]). However, the condition number is not completely devoid of the drawbacks of the manipulability index since the determinant of the Jacobian is still a component of the condition index [9].…”