The problem of change detection in signals using linear regression models is addressed. The most algorithms presented make use of two AR models: the first one is a reference model and the second one is a current model...
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The problem of change detection in signals using linear regression models is addressed. The most algorithms presented make use of two AR models: the first one is a reference model and the second one is a current model updated via a sliding block. Changes are detected when a suitable distance between these two models is high. Three distance measures are considered in the paper: cepstral distance, log-likelihood ratio (justified by GLR) and a distance involving the cross-entropy of the two conditional probabilities laws (divergence test). Finally, a change detection algorithm using three models and the evolution of Akaike Information Criterion is presented. Some results on the application of the discussed algorithms in seismic signal segmentation are included.
This paper presents an integrated environment which fills a gap between controlsystemdesign and real-time implementation of control algorithms. The integrated environment uses a standard hardware platform, a standar...
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ISBN:
(纸本)0769501346
This paper presents an integrated environment which fills a gap between controlsystemdesign and real-time implementation of control algorithms. The integrated environment uses a standard hardware platform, a standard operating system and computeraidedcontroldesignsystem as design tool. This contribution focuses on application of a rapid prototyping toolbox which automatically generates real-time code for Windows 95/98/NT operating systems. The code is created from the Simulink model of the controller. The real-time properties of the controlsystem are analysed. The inverted pendulum control example is used to illustrate the efficiency of the proposed solution.
One of the main difficulties in applying modern control theories for designing robust controllers for linear uncertain plants is the lack of adequate models describing structured physical model uncertainties. We prese...
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One of the main difficulties in applying modern control theories for designing robust controllers for linear uncertain plants is the lack of adequate models describing structured physical model uncertainties. We present a systematic approach for the generation of uncertainty models described by linear fractional transformations (LFTs) and report on recently developed symbolic and numerical software to assist the generation of low order LFT-based uncertainty models. The kernel of the symbolic software is a Maple library for generation and manipulation of LFT models. Additional numerical tools for order reduction of LFT models are based on MATLAB and FORTRAN implementations of numerically reliable algorithms. Three examples of uncertainty modeling of aircraft dynamics illustrate the capabilities of the new software to solve high order uncertainty modeling problems.
This paper illustrates an efficient way of modeling mechanical systems and performing the numerical simulation by combinationally using symbolic and numerical computation tools. Since deriving the model and its minima...
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This paper illustrates an efficient way of modeling mechanical systems and performing the numerical simulation by combinationally using symbolic and numerical computation tools. Since deriving the model and its minimal representation involves symbolic manipulations of equations, it must be handled by the symbolic computation tool. On the other hand, the simulation task requires numerical evaluations of the same object repeatedly: it can be efficiently processed by the numerical tool, especially when the values of objects are immediately available. The key point is how to export the symbolic objects easily into the numerical environment. The authors try to automatically generate source codes of the objects for the numerical tool, and join two environments on the source level. The stabilization of the spherical pendulum is served as an example, and its modeling and the simulation using Mathematica/MaTX are included.
Modelica is an object-oriented language for modeling of large, complex and heterogeneous physical systems. It is suited for multi-domain modeling, for example for modeling of mechatronics including cars, aircrafts and...
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Modelica is an object-oriented language for modeling of large, complex and heterogeneous physical systems. It is suited for multi-domain modeling, for example for modeling of mechatronics including cars, aircrafts and industrial robots which typically consist of mechanical, electrical and hydraulic subsystems as well as controlsystems. General equations are used for modeling of the physical phenomena. No particular variable needs to be solved for manually. A Modelica tool will have enough information to do that automatically. The language has been designed to allow tools to generate efficient code automatically. The modeling effort is thus reduced considerably since model components can be reused and tedious and error-prone manual manipulations are not needed. The principles of object-oriented modeling and the details of the Modelica language as well as several examples are presented.
The decomposition of a system into modular components, together with abstractions of the components, can allow a computationally difficult global verification task to be broken into a number of smaller, more manageabl...
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The decomposition of a system into modular components, together with abstractions of the components, can allow a computationally difficult global verification task to be broken into a number of smaller, more manageable verification subtasks. We provide the first known non-trivial application of modular verification in conjunction with the model-checking paradigm for verifying hybrid systems. We verify a fault-tolerant active structure controlsystem. The controlsystem is a version of one originally presented and analyzed in [ECB94, ECB97]. While the minimization method of [ECB94, ECB97] is automated, it also requires the abstractions to have exactly the same behaviors as their implementations. Our verification methodology differs in that we must provide explicit abstractions of the system components. However, we allow abstractions that are more abstract than the components themselves. General guidelines are given for the development of suitable abstractions.
This paper discusses simultaneous design of plant structure and a controller with two-degree-of-freedom. We propose a new criterion for a feedforward property with a concrete design procedure of controllers, which is ...
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This paper discusses simultaneous design of plant structure and a controller with two-degree-of-freedom. We propose a new criterion for a feedforward property with a concrete design procedure of controllers, which is suitable for a simultaneous design problem. Numerical example demonstrates the effectiveness of the proposed criterion. It also shows that feedforward and feedback properties are not independent in case of simultaneous design.
The existing compensation designs for the ALFA adaptive optics system that is implemented on the 3.5 meter telescope at the Calar Alto observatory are presented. The ALFA system uses a modal compensation architecture....
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The existing compensation designs for the ALFA adaptive optics system that is implemented on the 3.5 meter telescope at the Calar Alto observatory are presented. The ALFA system uses a modal compensation architecture. The modal compensation design problem is highlighted and the comparative and scientific results obtained with the compensator designs are also presented.
Integrated optimum design of structure and controlsystem is expected to achieve the higher performance of various mechanical systems. Recently, a lot of efforts to develop the integrated optimization methods have bee...
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Integrated optimum design of structure and controlsystem is expected to achieve the higher performance of various mechanical systems. Recently, a lot of efforts to develop the integrated optimization methods have been tried in order to improve the dynamic characteristics of the combined structure/controlsystems. The objective of this paper is to present some concepts of the integrated optimum design in vibration control problems. Some integrated optimization problems are introduced with the applications conducted by the authors.
This paper will describe the convergence of automatic code generation from graphical diagrams and Real Time Operating system (RTOS) technology. The two fields have developed for some time independently of each other b...
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This paper will describe the convergence of automatic code generation from graphical diagrams and Real Time Operating system (RTOS) technology. The two fields have developed for some time independently of each other but recent developments in both fields have initiated a melding of the two. Particularly, in the field of automatic code generation the concept of configurable code generators which allow the user to make compromises between speed and program size as well as the format and style of the code have allowed this technology to branch out of its more traditional rapid-prototyping and desktop simulation strongholds. In the area of operating systems, the relatively recent launch of the OSEK specification has provided the foundation for automotive manufacturers and suppliers to make use of commercially available operating systems for their applications. This paper presents several techniques which allow a configurable C code generator, such as AutoCode, to efficiently use the utilities provided by an OSEK compliant RTOS to develop portable and reusable software for automotive Electronic control Units.
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