Boundary Control For Flexible Manipulator Research Articles

LMI-based boundary control of flexible manipulator with external disturbance

In this paper, we address the LMI-based boundary control issue of a flexible manipulator subject to external disturbance. First, the dynamics of the system is characterised by several partial differential equations (PDEs). Second, in order to realise the disturbance rejection, we propose two disturbance observers. Based on these observers, two boundary control protocols are designed via the linear matrix inequality (LMI) method for suppressing elastic vibration and regulating the angle of the joint. A significant feature of LMI is that the control gains can be efficiently solved. Finally, some simulation examples illustrate the effectiveness of the proposed theoretical results.

Nussbaum function‐based adaptive boundary control for flexible manipulator with unknown control directions and nonlinear time‐varying actuator faults

AbstractThis study proposes a novel boundary control strategy for a vibrating single‐link flexible manipulator system modeled by partial differential equations. The system has uncertain control directions and actuator faults. Existing research studies model fault‐tolerant control systems with fixed fault coefficients; in this study, the actuator faults are nonlinear and time‐varying, and the control directions are unknown. To circumvent the obstacles introduced by the unknown control directions and nonlinear varying actuator failures, an adaptive boundary controller is designed by using Nussbaum functions with fast growth rates and the bound estimation method. In the developed control scheme, all closed‐loop signals are shown to be uniformly bounded. Additionally, the angle tracking error and vibration asymptotically converge to zero. Finally, numerical simulations for five cases demonstrate the effectiveness of the modeled boundary controller.