In this thesis, we present a new method for designing multirate signal processing and digital communication systems via sampled-data H control theory. The difference between our method and conventional ones is in the signal spaces. Conventional designs are executed in the discrete-time domain, while our design takes account of both the discrete-time and the continuoustime signals. Namely, our m...

This paper studies order reduction issues for a vehicle active suspension system throughout its modelling, H-infinity controller design and controller refinement. Computer simulations demonstrate that an H-infinity controller for a full active suspension can be significantly reduced to nearly one third of its full order, while the active suspension performance is only slightly degraded. As a by...

This work extends the current results of SISO (single-input-single-output) case H-infinity PID Controller synthesis in finite frequency domain to the subject of multivariable decentralized control. Sufficient conditions for the existence of such a decentralized PID controller are derived in terms of linear matrix inequalities (LMIs). A numerical example is given that establishes the efficacy of...

When designing controllers with robust performance and stabilization requirements, H-infinity synthesis is a common tool to use. These controllers are often obtained by solving mathematical optimization problems. The controllers that result from these algorithms are typically of very high order, which complicates implementation. Low order controllers are usually desired, since they are consider...

This paper describes a micro-force sensing device where a H-infinity control scheme is used to actively balance the external force and provide the measurement. The force sensing principle is based on the active control of the electrostatic bipolar actuator (comb-drive) within the sensor. An external load force acts on the sensor and displaces the probe. The controller is set to balance the appl...

This paper describes the development of H∞ controllers for two helicopter models. The study was first carried out using rigid body state feedback only and was then extended to include the rotor flap and lag states. It was observed that the H∞ controllers gave better robustness and performance than the baseline controllers. Moreover, using rotor state feedback, it was possible to design high ban...

In this paper, we propose a novel H-infinity filter based particle filter (H∞PF), which incorporates the H-infinity filter (H∞F) algorithm into the particle filter (PF). The basic idea of the H∞PF is that new particles are sampled by the H∞F algorithm. Since the H∞F algorithm can fully take into account the current measurements, when the new algorithm calculates the proposed probability density...

The paper deals with the problem of a robust actuator fault diagnosis for Linear Parameter-Varying (LPV) systems with Recurrent Neural-Network (RNN). The preliminary part of the paper describes the derivation of a discrete-time polytopic LPV model with RNN. Subsequently, a robust fault detection, isolation and identification scheme is developed, which is based on the observer and H∞ framework f...

This paper is concerned with the quantized H∞ filtering problem for discrete-time systems. The quantizer considered here is dynamic and composed of a dynamic scaling and a static quantizer. Motivated by practical transmission channels requirements, the static quantizer ranges are fully considered in this paper. A quantized H∞ filter design strategy is proposed with taking quantizer errors into ...

In current AFM-based nanomanipulation systems, the commercial position closed-loop controller for piezoelectric nanopositioning stages are implemented with success in a wide range of industrial applications. Even if these controllers operate with satisfactory nominal tracking performance, considerable attention has been focused on appropriate control strategies to compensate hysteresis, nonline...