On the Invariance of Manipulability Indices
نویسندگان
چکیده
This work discusses the invariance of local manipulability indices which are used to convert into a scalar the capability of a robotic device at a given configuration to perform a manipulation task. It is shown that they suffer from non–invariance in the sense that arbitrariness in the choice of the metric functions employed in their definition is unavoidable and they are not invariant under changes of the arbitrary choices introduced. Since there do not exist natural norms in the spaces of generalized forces and velocities, kinematic manipulability is neither an invariant concept nor a natural notion.
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