Control design and performance evaluation for flexible manipulators
Abstract
To date, many manipulator designs have been based on rigid body considerations. These designs are often characterized by stiff structures and sluggish responses, while flexible manipulator designs are recognized for such benefits as energy-efficiency and maneuverability. The increasing demands for more accurate modeling of the flexible manipulators result in larger and more complex nonlinear models with more degrees of freedom. For realistic problems, the required algebra becomes prohibitive and error-prone by paper and pencil. Symbolic processing of nonlinear equations of motion, based on Lagrange formulation and the assumed-modes method, has been employed extensively in this study. Since a flexible structure is a distributed-parameter system, any finite-dimensional attempt to control such as system is not free from the ill-effects of intrinsic model errors. A suboptimal gain scheduling scheme with model error accommodation to control flexible manipulators is presented. For the performance evaluation of a control design, a nonlinear closed-loop simulation should be carried out under realistic model error environments. Simplification of such an evaluation process by combined use of a simulation language and a properly interfaced symbolic manipulation system is discussed. The effectiveness of both the model-error-accommodating control and the performance evaluation process is demonstrated by an example.
Degree
Ph.D.
Advisors
Citron, Purdue University.
Subject Area
Mechanical engineering
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