Identification in view of control design of a CD player Identi cation in view of control design of a CD player z

Abstract. Electro mechanical servo systems, as encountered in consumer electronic products, have t o k eep pace with increasingly high performance demands. As the mechanical construction is a restricting factor regarding the limits of achievable performance, model based control design is proposed to enhance the bandwidth. System identi cation proves to be an adequate tool to produce nominal models and uncertainty models that are suitable for control design purposes. A method based on performing identi cation and control design in an iterative manner is proposed in order to systematically enhance the disturbance attenuation properties of a servo system. The proposed method is experimentally veri ed via application to a compact disc servo m e c hanism

Aliasing of resonance phenomena in sampled-data control design: Hazards, modeling, and a solution

Abstract-High-performance control design for electromechanical sampled-data systems with aliased plant dynamics is investigated. Though from a theoretical viewpoint the aliasing phenomenon is automatically handled by direct sampled-data control, such an approach cannot be used in conjunction with models derived through system identification. From a practical viewpoint, aliasing is often considered as an undesirable phenomenon and a typical remedy is the increase of the sampling frequency. However, the sampling frequency is upper bounded due to physical and economical constraints and aliasing may be inevitable. Control design for plants with aliased dynamics has not received explicit attention in the literature and it is not clear how to handle this situation. In this paper, it is shown that aliased resonance phenomena can effectively be suppressed in sampled-data feedback control design without the need for increasing the sampling frequency. Furthermore, it is shown experimentally on an industrial wafer stage that ignoring aliasing during control design can have a disastrous effect on closed-loop performance. Additionally, a novel, practically feasible procedure for identification of (possibly aliased) resonance phenomena based on multirate system theory is proposed

Modeling local/periodic temperature variation in catalytic reactions

Abstract-This paper introduces a dynamic simulation model for investigation of local and transient effects in catalytic reaction systems. More specifically, the model allows inspection of the effects of supplying thermal energy directly to the catalytic particles in stead of applying energy to the whole reactor volume. With simulation results it is shown that for a certain type of catalytic reaction system the obtainable yield of product and the selectivity of the reaction toward that product can be significantly increased when thermal energy is supplied directly to the catalyst. It is also shown that the results can be improved even further by supplying thermal energy periodically in stead of continuously

Norm Optimal Cross-Coupled Iterative Learning Control

Abstract-In this paper, we focus on improving contour tracking in precision motion control (PMC

Next-generation wafer stage motion control : connecting system identification and robust control Citation for published version (APA): Next-Generation Wafer Stage Motion Control: Connecting System Identification and Robust Control

Abstract-Next-generation precision motion systems are lightweight to meet stringent requirements regarding throughput and accuracy. Such lightweight systems typically exhibit lightly damped flexible dynamics in the controller cross-over region. State-of-the-art modeling and motion control design procedures do not deliver the required model fidelity to control the flexible dynamical behavior. In this paper, identification and control challenges are investigated and a novel approach for next-generation motion control is presented. The procedure is applied to a multivariable wafer stage, confirming a significant performance improvement