Disturbance Observer based robot control algorithms provide good 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 Sadegh ...

In this paper, an observer–based controller is designed for the problem of congestion control . In TCP/IP networks, the packets-dropping probability function is considered as a control input. Therefore, the work described here is to design robust observer controller, which is aimed at robust stabilization of network system with uncertainties, input delay and a saturated input. The controller is...

This paper deals with the problem of sensor fault tolerant control for Takagi-Sugeno nonlinear systems. Firstly, a residual generator is designed in order to detect and isolate sensor faults. Secondly, a nonlinear observer based controller, adopting the so-called parallel distributed compensation structure is designed. This controller is based on a weighted blending of the estimated states prov...

This paper deals with the robust control for Four Wheels Steering (4WS) vehicle dynamics when the road adhesion conditions change and the sideslip angle is unavailable for measurement. The nonlinear model of the vehicle, is firstly represented by a uncertain Takagi-Sugeno (T-S) model. Next, robust output stabilization of vehicle is considered. The controller and the observer are designed in ter...

Passivity-based control methods for robots, which achieve the control objective by reshaping the robot system’s natural energy via state feedback, have, from a practical point of view, some very attractive properties. However, the poor quality of velocity measurements may significantly deteriorate the control performance of these methods. In this paper we propose a design strategy that utilizes...