In this paper, we consider a controller failure time analysis problem for a class of symmetric linear time-invariant (LTI) systems controlled by a pre-designed symmetric static output feedback. We assume that the controller fails from time to time due to physical or purposeful reason, and analyze stability and H∞ disturbance attenuation properties for the entire system. Our objective is to find...

This paper investigates the tracking control of a wheeled mobile robot in the unknown environment. A disturbance observer is developed with utilization the integral filter. The proposed control scheme employs the disturbance observer control approach to design an auxiliary wheel velocity controller to make the tracking errors, which includes the velocity tracking error, the angular velocity tra...

The problem of networked control under disturbance and jamming attacks is investigated. Specifically, the control input packets are assumed to be transmitted from the controller to a linear plant over an insecure wireless communication channel that faces jamming attacks. The likelihood of transmission failures on this channel depends on the power of the jamming interference signal emitted by an...

This paper presents an indirect adaptive system based on neuro-fuzzy approximators for the speed control of induction motors. The uncertainty including parametric variations, the external load disturbance and unmodeled dynamics is estimated and compensated by designing neuro-fuzzy systems. The contribution of this paper is presenting a stability analysis for neuro-fuzzy speed control of inducti...

Employing disturbance observers is an effective way of enhancing the stability and performance of the control systems subject to disturbances. Disturbance observers have been extensively used for control of mechatronic systems since their introduction in the 1980s. This thesis studies the design of nonlinear disturbance observers for robotic manipulators and their applications in the control of...

We consider the almost disturbance decoupling problem (ADDP) and/or almost D-bounded disturbance decoupling problem ((ADDP) D) with internal stability for linear systems subject to input saturation and input-additive disturbance via linear static state feedback. We show that the almost D-bounded disturbance decoupling problem with local asymptotic stability ((ADDP/LAS) D) is always solvable via...

This paper proposes a control parametrization under Model Predictive Controller (MPC) framework for constrained linear discrete time systems with bounded additive disturbances. The proposed approach has the same feasible domain as that obtained from parametrization over the family of time-varying state feedback policies. In addition, the closed-loop system is stable in the sense that the state ...

Disturbance observer based robot control algorithms provide good control performance while giving a straightforward method of gain selection. Unfortunately, the stability of these algorithms has not been shown rigorously for nonlinear systems such as robots. This paper demonstrates that a disturbance observer based algorithm can be made equivalent to the well-known passivity-based approaches of...

The stability of spacecraft attitude is studied with considering sinusoidal disturbance. A passive attitude controller without angular velocity measurement for spacecraft described by quaternion is designed. The passive controller has no information related to system parameters. So it has robustness to model error and uncertainty of model parameters. The stability of spacecraft attitude control...