Showing papers by "M Maarten Steinbuch published in 2000"

Internal-model-based design of repetitive and iterative learning controllers for linear multivariable systems

Abstract: Repetitive and iterative learning control are two modern control strategies for tracking systems in which the signals are periodic in nature. This paper discusses repetitive and iterative learning control from an internal model principle point of view. This allows the formulation of existence conditions for multivariable implementations of repetitive and learning control. It is shown that repetitive control can be realized by an implementation of a robust servomechanism controller that uses the appropriate internal model for periodic distrubances. The design of such controllers is discussed. Next it is shown that iterative learning control can be implemented in the format of a disturbance observer/compensator. It is shown that the resulting control structure is dual to the repetitive controller, and that both constitute an implementation of the internal model principle. Consequently, the analysis and design of repetitive and iterative learning control can be generalized to the powerful analysis and design...

Input design for optimal discrete time point-to-point motion of an industrial XY-positioning table

Abstract: A technique is presented to design input signals for point-to-point control problems with the property of minimal excitation of parasitic system oscillations. This technique is compared to impulse based input design techniques in experiments performed on an industrial XY-positioning table. Impulse input shaping was formulated as a solution to an optimisation problem, which has been transformed for the case of point-to-point problems, resulting in a more time-optimal solution. The results from this new optimisation are very impressive considering the simplicity.

SIDO controller design for a high performance optical drive

Abstract: This paper presents the results of a single-input/dual-output (SIDO) control design for a high performance optical drive. The optical drive consists of a dual-input/single-output (DISO) actuator: both a sledge actuator and a rotating mirror contribute to a radial movement of the spot on the disk. The used controller design method is a modified version of the PQ design method. The design method reduces the problem to two SISO design problems for which frequency response design techniques can be used. The first step is focused on designing a parallel combination of the two subsystems such that the parallel plant allows optimal design freedom. The second design issue is the design of the controller for the created parallel system. Here, the focus is on stability and achieving performance specifications. The design method leads to good insights in the system characteristics.

Robust control of a compact disc mechanism

Abstract: A compact disc (CD) player is an optical decoding device that reproduces high-quality audio from a digitally coded signal recorded as a spiral-shaped track on a reflective disc. Apart from the audio application, other optical data systems (CD-ROM, optical data drive) and combined audio/video applications (CD-interactive, CD-video) have emerged. An important research area for these applications is the possibility of increasing the rotational frequency of the disc to obtain faster data readout and shorter access time. For higher rotational speeds, however, a higher servo bandwidth is required that approaches the res onance frequencies of bending and torsional modes of the CD mechanism. Moreover, the system behavior varies from player to player because of manufacturing tolerances of CD players in mass production, which explains the need for robustness of the controller. Further, an increasing percentage of all CD-based applications is for portable use. Thus, additionally, power consumption and shock sensitivity play a decisive role in the performance assessment of controller design for CD systems. In this chapter we concentrate on the possible improvements of both the track-following and focusing behavior of a CD player, using robust control design techniques.

Optimisation oriented modelling of airbag and belt

Abstract: Today's Safety Restraint Systems are a compromise in that they are optimised for standard crashes and only take the most important crash characteristics into account when activated. This paper is about how to optimise the design parameters of the airbag and the belt for a large class of crashes. The curently used multibody models are far too complex for optimisation. The key-issue is to find a metamodel, i.e. an easy-to-calculate approximation for the time-consuming full analysis model. This metamodel then can be used in the iterative optimisation process. Here, the theory of design of experiments in combination with multiple regression, using the full model for the 'experiments', is applied to find the metamodel. The results show that the obtained model is accurate enough to be used for the optimisation of the design parameters. However, the metamodel is applicable only for one crash, i.e. all parameters in the full analysis model to characterise the crash and the occupant have to be fixed a priori. Further research enabling the metamodel to cover a large class of crashes is recommended. For the covering abstract see ITRD E109346.

Safe Tech: A Control Oriented Viewpoint

Abstract: The interplay between processes and real-time software systems, together constitution a closed-loop system, is not trivial to investigate For the 'low level' feedback loop much theory is available, however, for the supervisory level where discrete events may interfere with the dynamics of the system, no complete theory for analysis and synthesis exists For controlled manipulator systems simulation examples show the effects of delay and start/stop scheduling for the controlled output variables A common language for software development and dynamic systems is needed to be able to design embedded systems, in particular for safety critical applications