Methodology for integrated manufacturing planning and control systems design

After the description of the underlying principles on which the “multiagentbased production control” technology and the “holonic manufacturing control” concept within the intelligent manufacturing system paradigm are based, this work proposes an approach that supports the design of agent-based manufacturing control systems for different industrial holonic manufacturing scenarios. The results of the application to a pilot cell at industrial level are very promissory, showing that the approach seems to be very suited in accommodating heterogeneous hardware and software components in both their manufacturing control and information system, and in integrating existing/legacy systems.KeywordsFlexible Manufacturing SystemProduction AgentLogical DependencyTransport AgentManufacturing ObjectThese keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.

PurposeDrawing on Simons's levers of control (LoC) framework, the primary aim of this study is to advance an understanding of the balance between empowerment and constraint in a non-profit UK organisation. In particular, this study examines the antecedents and manifestations of LoC (im)balance, in relation to employees' level of engagement with the control systems in place.Design/methodology/approachFor this study, 27 semi-structured interviews were conducted with different organisational members, from directors to non-managerial staff, to gain an in-depth appreciation of the main differences between managerial intentions in the design of management control systems (MCS) and employee perceptions regarding the role of such systems.FindingsThis research reveals that suppression of interactive systems and internal inconsistencies between different types of controls hinder the balance between empowerment and constraint. This imbalance is then found to have important consequences for employee buy-in, in some cases, defeating the purposes of control.Research limitations/implicationsThis study enhances our understanding of the gap between the design of control systems and the employee perceptions of it in an unusual organisational setting (non-profit and bringing together clinical and non-clinical staff and operations).Originality/valueThe study of MCS and its role in organisations has long been the focus of both academic and practitioner research. Yet, while extant literature focused on management's perspective on MCS, few studies have explored employees' attitudes and behaviours that accompany the implementation of control. What is more, little is known about the specific uses and behavioural outcomes of MCS in the context of non-profit organisations. Drawing on Simons's LoC framework, this paper addresses these gaps in the literature and investigates the balance between control and empowerment of employees in a UK non-profit organisation with significant clinical remit.

A method is described for using nonlinear programing in the computer-aided design of airplane control systems. It is assumed that the quality of such systems depends on many criteria. These criteria are included in the constraints vector (instead of attempting to combine them into a single scalar criterion, as is usually done), and the design proceeds through a sequence of nonlinear programing solutions in which the designer varies the specification of sets of requirements levels. The method is applied to design of a lateral stability augmentation system (SAS) for a fighter airplane, in which the requirements vector is chosen from the official handling-qualities specifications. Results are shown for several simple SAS configurations designed to obtain desirable handling qualities over all design flight conditions with minimum feedback gains. The choice of the final design for each case is not unique but depends on the designer's decision as to which achievable set of requirements levels represents the best for that system. Results indicate that constant gain systems can substantially exceed the highest required levels of handling qualities in all design flight conditions of the example considered. The role of the designer as a decision maker, interacting with the computer program, is discussed. Advantages of this type of designer-computer interaction are emphasized. Desirable extensions of the method are indicated.

10 - Robust design of intelligent control systems to mitigate earthquake-induced vibrations under uncertain conditions

Need of use of computer technology for conceptual design of control systems' elements for electric power system was proved. The known approaches to the solution of this task are analysed and need of their development is proved. New approach to conceptual design of control systems' elements on the basis of the fractal theory is observed. Two types of self-similarity for functional fractals were defined: rigid and non-rigid self-similarity. Use of this approach allows to model sensors of new generation, in particular, multiifunctional sensors.

Control systems are pervasive in our lives. Our homes have environmental controls. The appliances we use, such as the washing machine, microwave, etc. carry embedded controllers in them. We fly in airplanes and drive automobiles that extensively use control systems. The industrial plants that produce consumer goods run on process control systems. The recent drive toward automation has increased our reliance on control systems technology. This book discusses control systems design from a model-based perspective for dynamic system models of single-input single-output type. The emphasis in this book is on understanding and applying the techniques that enable the design of effective control systems in multiple engineering disciplines. The book covers both time-domain and the frequency-domain design methods, as well as controller design for both continuous-time and discrete-time systems. MATLAB© and its Control Systems Toolbox are extensively used for design. Technical topics discussed in the book include: • Mathematical models of physical systems • Analysis of transfer function and state variable models • Control systems design objectives • Control system design with root locus • Control system design in the state-space • Control system design of sampled-data systems • Compensator design with frequency response methods

Control systems are pervasive in our lives. Our homes have environmental controls. The appliances we use, such as the washing machine, microwave, etc. carry embedded controllers in them. We fly in airplanes and drive automobiles that extensively use control systems. The industrial plants that produce consumer goods run on process control systems. The recent drive toward automation has increased our reliance on control systems technology. This book discusses control systems design from a model-based perspective for dynamic system models of single-input single-output type. The emphasis in this book is on understanding and applying the techniques that enable the design of effective control systems in multiple engineering disciplines. The book covers both time-domain and the frequency-domain design methods, as well as controller design for both continuous-time and discrete-time systems. MATLAB© and its Control Systems Toolbox are extensively used for design. Technical topics discussed in the book include: • Mathematical models of physical systems • Analysis of transfer function and state variable models • Control systems design objectives • Control system design with root locus • Control system design in the state-space • Control system design of sampled-data systems • Compensator design with frequency response methods

A multiple-logistic-objective-optimized (MLOO) manufacturing planning and control approach is developed in an attempt to optimize the logistics objectives of a short throughput time, a low work in process, and high schedule reliability. The proposed approach also needs to effectively cope with disturbances including internal disturbances (equipment failure, rework, etc.) and external disturbances (variations in demand patterns, unsatisfied raw material delivery, etc.). This paper focuses on make-to-order manufacturing systems with routing flexibility. Simulation experiments are conducted using industrial data in order to compare the MLOO approach with several existing methods. The simulation results indicate that MLOO is able to optimize the target logistics objectives and effectively cope with disturbances.

While linear covariance analysis is widely used for navigation system design and analysis, it is often overlooked as a tool for closed-loop guidance navigation and control (GN&C) system design and analysis. This article presents an overview of the techniques and methods required to develop a linear covariance analysis tool for a close-loop GN&C system. Then, using a simple nonlinear closed-loop GN&C problem as a guide, the capabilities of linear covariance analysis for the design and analysis of closed-loop systems are demonstrated. It is shown that linear covariance can be accurately applied to a closed-loop system with time-to-go guidance, dead-reckoning navigation, and a Kalman filter for state estimation. The accuracy and efficiency of linear covariance analysis is shown by direct comparison to Monte Carlo analysis results, and the value of linear covariance analysis is highlighted by presenting several analysis capabilities that are often required in the design and analysis of closed-loop GN&C systems. It is also shown how the efficiency of linear covariance enables new design methodologies, one of which is presented in this article, that would otherwise be prohibitive with Monte Carlo analysis.

Command and control systems centralize information from multiple underlying systems to support operators in the performance of their mission. Beyond the mission itself (that may be complex), operators must also ensure the correct functioning of these systems (often called platform). Platform systems (e.g. engines or electric system) may be very different from each other and exhibit a large number of functional states. When applied to the design of command control systems, User Centered Design methods support understanding and capturing operators’ needs to perform the mission, as well as to propose solutions to design usable mission-related user interfaces. However, user interfaces for platform management need to present and organize information about the underlying complex systems. Understanding those systems and abstracting away information about their behavior (so that operators can manage them) requires deep knowledge beyond UI/UX designers and UCD methods experts. In this paper, we propose a system-centered process that would complement UCD approaches for the design of command and control systems. That process takes as input the detailed functioning of underlying systems and provides abstract and structured information to inform UCD methods. Beyond supporting usability property, the integrated process supports reliability and safety properties that UCD approaches usually overlook. We present how the proposed process has been applied for the design of a large civil commercial aircraft warning system and show generalizability to other domains.

Rotorcraft flight control systems present design challenges which often exceed those associated with fixed-wing aircraft. First, large variations in the response characteristics of rotorcraft result from the wide range of airspeeds of typical operation (hover to over 100 kts). Second, the assumption of vehicle rigidity often employed in the design of fixed-wing flight control systems is rarely justified in rotorcraft where rotor degrees of freedom can have a significant impact on the system performance and stability. Proposed herein is a methodology for the design of robust rotorcraft flight control systems utilizing Quantitative Feedback Theory (QFI'), a technique which accounts for variability in the dynamic response of the controlled element in the design of robust control systems. It was developed to address a Multiple-Input-Single-Output (MISO) design problem, but was extended to the address the Multiple-Input-Multiple-Output (MIMO) flight control system (FCS) design problem of a UH-60 Black Hawk Helicopter. Inherent conservatism in this design technique leads to limitations in its utility. A modified QFI' approach proved a viable method for designing robust MIMO flight control systems. An analysis of the two flight control system design methodologies is presented.

Energy functions have been used in power systems for direct stability analysis, designs of control systems and stability analysis. The existing energy functions have been developed under the assumption that limit sets are composed exclusively of hyperbolic equilibrium points. However, the structure of limit sets for general power system dynamical models can be very complex; limit sets can be composed of equilibrium points, closed orbits, quasi-periodic solutions, or chaotic trajectories. The existing energy functions are not applicable to these general power system dynamical models. To this end, generalized energy functions are developed for these general dynamical models. In this paper, generalized energy function along with a comprehensive generalized energy function theory are developed. It will be shown that energy functions do not exist for some general power system dynamical models while generalized energy functions exist. With the developments of generalized energy functions, it is feasible to extend the existing energy-function-based tools to general power system dynamical models. In particular, it is feasible to perform direct stability analysis, designs of control systems and stability analysis of equilibrium points, closed orbits for extended transient stability models as well as mid-term stability models.

The inward approach in the design of control systems is introduced. This approach differs from the root-locus and the Bode-plot methods in that it involves first searching for an overall transfer function to meet design specifications and then computing the required compensator. The method is simple and straightforward and can easily be carried out with the aid of a digital computer simulator program.< <ETX xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">&gt;</ETX>

The object of this work is to present computer programs, written using Turbo Pascal version 5.5, which can be utilized for the analysis and design of control systems as required for undergraduate courses. The programs have been designed so that the student uses the computer as a tool for reducing computational drudgery and not as a substitute for engineering analysis. The software, which can be used on an IBM Personal Computer and compatibles, will be made freely available to interested educators. >

Abstract: MAID is an expert system for the computer‐aided design of control systems. It is developed in conjunction with the successful application of a systematic control system design technique. The design problem has been decomposed into sub‐problems, resulting in good modularity of design knowledge. Interactive design and the designer's intuition are emphasized. MAID, which acts as a designer's assistant, was developed using the expert systems development facility provided within a control system design package. The coupling of symbolic and numerical processing was carried out in a natural way.