This paper proposes a novel method to design an H∞-optimal fractional order PID (FOPID) controller with ability to control the transient, steady-state response and stability margins characteristics. The method uses particle swarm optimization algorithm and operates based on minimizing a general cost function. Minimization of the cost function is carried out subject to the H∞-norm; this norm is ...

This paper presents an extension of the HIFOO toolbox for Matlab for fixed-structure and fixed-order H∞ controller design to discrete-time controller design. The approach is applied to a restricted complexity controller synthesis problem for an active suspension system.

This article focuses on the design of a discrete robust H∞ controller for an input–shaped, underdamped, (stable or unstable) system. The system is noiseless, uncertain, time– invariant and its characteristic polynomial coefficients are allowed to vary within predefined interval–sets. A discrete input shaper is used for the nominal system generating a pre– compensated discrete Finite Impulse Res...

A redesign method for discretizing a continuous-time controller is proposed. The resulting hybrid control system, for example with continuous-time plant and discrete-time controller, is stable, and performance including the system's inter-sampling behaviour can be optimized by approximating some chosen reference transfer function of the continuous-time control system. In order to obtain a tract...

This paper presents the design of a robust H∞ controller for fast tracking of an Atomic Force Microscope (AFM). The controller design is based on a physical model of the AFM piezoelectric tube positioner. External capacitors are connected in series with the x and y contacts of the piezoelectric tube to provide measured voltages which are proportional to the charge on the actuator. The parameter...

In this paper we use the theory of L disturbance attenuation for linear H and nonlinear systems to obtain solutions to the Nonlinear Benchmark Problem NLBP proposed in the paper by Bupp et al By considering a series expansion solution to the Hamilton Jacobi Isaacs Equation associated with the nonlinear disturbance attenuation problem we obtain a series expansion solution for a nonlinear control...

This study investigates H∞ finite-time synchronization (HFTS) problems for a general class of chaotic systems with external disturbances. The HFTS includes two control objectives; one is the finite-time synchronization and the other is the H∞ minimization. Here, the finite-time synchronization means the finite-time stabilization of the error system between the master and slave chaotic systems, ...

In this paper, the state feedback H∞ control problem for networked control systems with quantization and random communication delays is discussed. The random delays from the sensor to the controller and from the controller to the actuator are considered. The quantizer considered here is dynamic and composed of an adjustable zoom parameter and a static quantizer. A novel quantized random delay m...

In this paper, we design a robust lead compensator for a real Electromechanical Actuator (EMA) harmonic drive by introducing an approach based on H∞ control theory. Here, we address three main topics; experimental identification, uncertainty modelling, and robust control design for a real EMA harmonic drive system. This method verifies good tradeoff between the powerful H∞ controller and the un...

In this paper, a robust H∞ controller for a building structure with a time delay is studied. Firstly, the motion equation of the structural system with an explicit time delay is introduced. Then, the state space representation of a dynamic equation without any explicit time delay is deduced by a specific integral transformation to the time-delay equation. Secondly, a robust control method is ap...