Sensor Optimization for Fault Diagnosis in Multi-Fixture Assembly Systems With Distributed Sensing

Sensing for the system-wide diagnosis of dimensional faults in multi-fixture sheet metal assembly presents significant issues of complexity due to the number of levels of assembly and the number of possible faults at each level. The traditional allocation of sensing at a single measurement station is no longer sufficient to guarantee adequate fault diagnostic information for the increased parts and levels of a complex assembly system architecture. This creates a need for an efficient distribution of limited sensing resources to multiple measurement locations in assembly. The proposed methodology achieves adequate diagnostic performance by configuring sensing to provide an optimally distinctive signature for each fault in assembly. A multi-level, two-step, hierarchical optimization procedure using problem decomposition, based on assembly structure data derived directly from CAD files, is used to obtain such a novel, distributed sensor configuration. Diagnosability performance is quantified in the form of a defined index, which serves the dual purpose of guiding the optimization and establishing the diagnostic worth of any candidate sensor distribution. Examples, using a multi-fixture layout, are presented to illustrate the methodology. [S1087-1357(00)70801-X]

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Hierarchical Analysis of Thorax Models to Measure Tidal Volume

Current Directions in Biomedical Engineering ◽

10.1515/cdbme-2018-0102 ◽

2018 ◽

Vol 4 (1) ◽

pp. 429-432

Author(s):

Bernhard Laufer ◽

Sabine Krueger-Ziolek ◽

Knut Moeller ◽

Paul David Docherty ◽

Fabian Hoeflinger ◽

...

Keyword(s):

Tidal Volume ◽

Motion Tracking ◽

Optimization Method ◽

Optimal Combination ◽

Hierarchical Optimization ◽

Hierarchical Analysis ◽

Hierarchical Method ◽

Computational Costs ◽

Sensor Configuration ◽

Time Required

AbstractMotion tracking of thorax kinematics can be used to determine respiration. However, determining a minimal sensor configuration from 64 candidate sensor locations is associated with high computational costs. Hence, a hierarchical optimization method was proposed to determine the optimal combination of sensors. The hierarchical method was assessed by its ability to quickly determine the sensor combination that will yield optimal modelled tidal volume compared to body plethysmograph measurements. This method was able to find the optimal sensor combinations, in approximately 2% of the estimated time required by an exhaustive search.

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A Hierarchical Optimization Procedure for the Modelling of Mechanical Systems

Dynamical Problems of Rigid-Elastic Systems and Structures ◽

10.1007/978-3-642-84458-4_11 ◽

1991 ◽

pp. 91-102

Author(s):

H. A. Eschenauer ◽

H. H. Müller-Slany

Keyword(s):

Mechanical Systems ◽

Optimization Procedure ◽

Hierarchical Optimization

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Optimum Dimensions of Extended Surfaces Operating in a Convective Environment

Applied Mechanics Reviews ◽

10.1115/1.3119754 ◽

1992 ◽

Vol 45 (5) ◽

pp. 155-173 ◽

Cited By ~ 78

Author(s):

A. Aziz

Keyword(s):

Heat Dissipation ◽

State Of The Art ◽

Internal Heat ◽

Optimization Procedure ◽

Review Of The Literature ◽

Temperature Dependent ◽

Dual Purpose ◽

Extended Surface ◽

Extended Surfaces ◽

Temperature Dependent Thermal Conductivity

This article is devoted to the review of the literature on optimum dimensions of extended surfaces losing heat by pure convection to the surroundings. The review covers straight (longitudinal) fins, annular (radial) fins, and spines of different profile shapes. The optimum dimensions for each shape are given both in terms of the volume of the material as well as the heat dissipation. The effects of tip heat loss, variable heat transfer coefficient, internal heat generation, temperature dependent thermal conductivity, base convection, and primary surface thickness on the optimum dimensions are discussed. The optimization procedure is illustrated with several numerical examples. Areas of extended surface technology where further optimization studies are needed are identified. It is hoped that the article would serve the dual purpose of the state-of-the-art as well as a pedagogical review.

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Multi-Level Optimization Approach to Managing the Development of Hierarchical Socio-Economic Systems

Vestnik Volgogradskogo gosudarstvennogo universiteta. Ekonomika ◽

10.15688/ek.jvolsu.2020.3.2 ◽

2020 ◽

pp. 17-29

Author(s):

Roman Zhukov ◽

Keyword(s):

Target Function ◽

Optimization Procedure ◽

Impact Factors ◽

Economic Systems ◽

Optimization Approach ◽

Indicator Values ◽

Starting Point ◽

Standard Values ◽

Multi Level ◽

Formalized Description

The purpose of the article is to develop a multi-level optimization approach to the management of hierarchical socio-economic systems (HSES). The starting point of the approach is to build a model of the functioning of HSES at the regional level (meso–level), which includes a set of models that characterize the results of the functioning of elements and their aggregates that form subsystems – classes – within the framework of a formalized description of the object of research. For each element and subsystem (for the selected subsystems, its own model of functioning can be built) of the considered hierarchy level, particular and integral indicators of performance, efficiency and harmony, which serve as indicators of the set (normative, expected) functioning of HSES, are formed. If indicators deviate from standard values, an optimization procedure is performed, which consists in searching for such conditions (state and impact factors for each of the considered subsystems and their elements), in which indicator values will correspond to the standard (expected) values. In general, this problem is reduced to the problem of multi-criteria optimization, where the target function consists of a combination of private and aggregated production functions, the parameters of which are determined using the factor analysis of dependencies. Object and cybernetic models illustrating the multi-level optimization approach to the management of HSES are presented.

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Sensor Location Optimization for Fault Diagnosis in Multi-Fixture Assembly Systems

Journal of Manufacturing Science and Engineering ◽

10.1115/1.2830221 ◽

1998 ◽

Vol 120 (4) ◽

pp. 781-792 ◽

Cited By ~ 36

Author(s):

A. Khan ◽

D. Ceglarek ◽

J. Ni

Keyword(s):

Fault Diagnosis ◽

Fault Isolation ◽

Hierarchical Optimization ◽

Sensor Location ◽

Sheet Metal Parts ◽

Automotive Body ◽

Assembly Sequences ◽

Sensor Configuration ◽

Effectiveness Index ◽

Isolation Performance

The effectiveness of fault diagnosis in assembly is contingent on the effectiveness of the sensor measurement of assembled parts. Using a diagnosability enhancement methodology for a single fixture, a means to achieve an optimal sensor configuration for a multi-fixture assembly of sheet metal parts is proposed. A Hierarchical Group description of the assembly is used to build a State-Transition representation which, with fixture CAD information, is used in multi-level hierarchical optimization to arrive at the optima. A defined Coverage Effectiveness Index quantifies fault isolation performance. The index also serves to evaluate the performance effectiveness of the measurement station location and change in the sensor number. The approach has significant utility in automotive body assembly where system complexity makes the choice of sensor location vital to fault isolation performance. Examples using multi-fixture simulated and industrial automotive body assembly sequences are provided to illustrate the methodology.

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Ethical Concerns in Poultry Production: A German Consumer Survey About Dual Purpose Chickens

Journal of Agricultural and Environmental Ethics ◽

10.1007/s10806-019-09806-y ◽

2019 ◽

Vol 32 (5-6) ◽

pp. 905-925 ◽

Cited By ~ 3

Author(s):

Maria Busse ◽

Maria Lee Kernecker ◽

Jana Zscheischler ◽

Felix Zoll ◽

Rosemarie Siebert

Keyword(s):

Regime Shift ◽

Ethical Issues ◽

External Pressure ◽

Added Value ◽

Poultry Production ◽

In Ovo ◽

Dual Purpose ◽

Competitive Disadvantage ◽

Multi Level ◽

Socio Economic Factors

Abstract The paper offers insights into the acceptability of ethical issues in poultry production and how this situation provides an opportunity to transform the prevailing system into a more sustainable one. The survey among German consumers reveals that killing day-old chicks is a well-known practice and is rated as “very problematic”. In contrast, dual-purpose chickens are mostly unknown but are considered a positive alternative to killing day-old chicks (after the concept has been explained). Consumer clusters were identified regarding purchasing criteria for dual-purpose chickens, purchasing routines and socio-economic factors. Three of the five clusters—the perfectionists, idealists, and realists—turned out to be potential buyers. To develop a suitable marketing strategy, it is recommended that the added value of dual-purpose chickens be comprehensibly communicated. From a multi-level perspective, rearing dual-purpose chickens has a competitive disadvantage compared to system-compliant alternatives (in-ovo sexing, “lay hen brothers”). Through increasing external pressure, the different alternatives can jointly contribute to a regime shift.

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