Abstract
Typically in the kinematic control of manipulator arms the task of guiding the end effector along a trajectory is governed by equality constraints, all other tasks being considered secondary. This is a major cause of difficulty when other, often more important constraints are encountered, for example, joint motion limits, workspace boundaries, or obstacles. To overcome this problem the notion of an imaginary end effector connected to the real end effector via imaginary (or virtual) actuators is introduced. These imaginary actuators act as slack variables in the constraint equations. This enables the real end effector to deviate from its desired path in order to allow other constraints to be satisfied. Imaginary actuators can also be used to maintain control of an arm when it is driven beyond its kinematic range, or into singular configurations.
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© 1991 Springer-Verlag Wien
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Kovesi, P. (1991). Imaginary Kinematics. In: Stifter, S., Lenarčič, J. (eds) Advances in Robot Kinematics. Springer, Vienna. https://doi.org/10.1007/978-3-7091-4433-6_7
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DOI: https://doi.org/10.1007/978-3-7091-4433-6_7
Publisher Name: Springer, Vienna
Print ISBN: 978-3-211-82302-6
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