There are two significant goals in teleoperation systems: Stability and performance. This paper introduces an LMI-based robust control method for bilateral transparent teleoperation systems in presence of model mismatch. The uncertainties in time delay in communication channel, task environment and model parameters of master-slave systems is called model mismatch. The time delay in communicatio...

Closed-loop controllers use outputs of the system to improve overall stability and increase tolerance against external disturbances. The latter makes it possible to control inherently unstable systems. As expected, there are some important differences from open-loop controllers. Most importantly, we must distinguish between measurable outputs of the system and the properties we really want to c...

In this paper, an efficient method is presented to control the attitude of a satellite with ON-OFF actuator. The main objective of this novel method is to control the amplitude of the limit cycle which commonly appears in the steady state of such systems; and at the same time by consideration of real actuator constraints, reduce the fuel consumption of system. The Proposed method is a combinati...

This paper presents an improved direct torque control (DTC) algorithm as compared to a traditional DTC scheme. In the traditional scheme, a pair of hysteresis comparators is used to control motor stator flux and electromagnetic torque. This causes a variable switching frequency which results in a high flux and torque ripples. To mitigate these issues, an improved DTC algorithm based on a double...

Abstract This paper analyzes the principle of PWM rectifier and presents a unity power factor control method of PWM rectifier. Controller used double closed-loop PI control, which inner uses three-phase input current control method controlled by unity power factor and outer controls the output DC voltage of rectifier. Voltage phase detection methods which proposed could eliminate the affection ...

Ships at sea are affected by factors such as waves which will produce a swing phenomenon. By constantly measuring the attitude of the platform and the change in position, a control system is developed to eliminate all interferences and insulate disturbances to stabilize objects on the carrier and maintain dynamic attitude reference accurately. This paper explores controllers of marine platforms...

In this paper, a new T-S fuzzy hyperbolic delay model for a class of nonlinear systems with time-varying delay, is presented to address the problems of stability analysis and feedback control. Fuzzy controller is designed based on the parallel distributed compensation (PDC), and with a new Lyapunov function, delay dependent asymptotic stability conditions of the closed-loop system are derived v...

In identification for control with no unmodelled dynamics, the best controller performance is achieved by performing the identification in closed loop. Alan'S-We compare open loop versus closed loop identification when the identified model is used for control design, and when the system itself belongs to the model class, so that only variance errors are relevant. Our measure of controller perfo...

It is well known that subspace identification methods that assume open loop data without correlations between the input and noise, may give biased estimates when applied to closed loop data. The effect of the controller gain parameters on the quality of the identified model is studied when closed loop data are used. Several subspace identification methods (both open loop and closed loop methods...