Flexibility effects on the control system performance of large scale robotic manipulators

Abstract

Structural flexibility of robotic manipulators becomes significant and limits the performance
\nof a control system when manipulators are large structures, manipulating on large
\npayloads, and/or operating at high speeds. The question of when a manipulator can be
\nconsidered rigid or must be considered flexible is studied as a function of manipulator dynamics
\nand task characteristics. Results are interpreted in simple quantitative forms
\nwhich can be used as design and analysis tools to decide whether or not the manipulator
\nflexibility will be a significant factor for a given task condition. The limitations imposed
\nby the manipulator flexibility on the joint variable feedback control system performance
\nis determined using linear and nonlinear methods. The closed loop eigenstructure behavior
\nof finite dimensional models under joint variable feedback is studied and results are
\ncompared with the previously reported results.