The LQG/LTR Design Procedure for Nonlinear Robot Manipulators
Abstract: In this thesis, the multivariable robust control of nonlinear manipulator systems is based on the compute torque method and the LQG/LTR design procedure was proposed. This controller is able to handle the system that have modeling errors and external disturbances while it keeps the close-loop system robustness and satisfied the prescribed performance. In this research, the computed toque method is applied to design the proposed control law to form the main control structure by using the benefit of its feedback linearization strategy. The error dynamics of the plant is then formulated to the standard H2/H∞ control problem, which is easy to be applied by the LQG/LTR design procedure to find the optimal control gain and observer gains in the process of matching the target loop. With regard to the non-canceling nonlinear terms, the closed-loop system is formulated to the Lu’re-type problem form with sector-bounded uncertainties, which is then analyzed by the Multivariable Circle Criterion to discuss the stability and robustness. To verify the feasibility of proposed controller, one example with various external disturbances and parameter uncertainties is made and its computer simulation result shows the efficiency and feasibility of the proposed design methodology.
文章引用: 钟启瑞 , 黄正能 (2013) 机械手臂之LQG/LTR最佳控制综合设计。 动力系统与控制， 2， 1-10. doi: 10.12677/DSC.2013.21001
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