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Future trends of computer integrated manufacturing in electronics industry of Hong Kong.January 1988 (has links)
by Leung Wing-keung, Joseph, Mok Yan-hung, Albert. / Thesis (M.B.A.)--Chinese University of Hong Kong, 1988. / Bibliography: leaves 92-93.
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Design and implementation of a system for integrating material and process selection in automated manufacturingChen, Hsueh-Jen 21 April 1992 (has links)
Today's manufacturing environment is characterized by competition and
continuous change in product and process requirements. The concept of
"design for manufacturability" integrates product specifications with
manufacturing capabilities by considering the design and manufacturing
phases as an integrated system, evaluating the combined system during
the design phase of a product , and adjusting the design for maximum
efficiency and production economics.
This research focuses on one aspect of design for manufacturability,
that of process technology evaluation for a specified product design.
The objective of the proposed system developed in this study is to
evaluate technology alternatives for manufacturing a specified part
design and to identify the best combination of product-process
characteristics that would minimize production costs within the
constraints set by the product's functional requirements and available
processing technology.
The research objectives are accomplished by developing a simulation
based analysis system. The user inputs product specifications through
structural screens. The system maintains data bases of work and tool
materials, and machining operations. Based on user input, the system
then extracts appropriate information from these data bases, and
analyzes of the production system in terms of production economics, and
other operational measures such as throughput times and work-in-process
inventories. Sensitivity analysis may then be performed to explore
tradeoffs in design and production parameters. The system is completely
integrated, and a user with no prior experience of either simulation or
data base technology can use the system effectively. / Graduation date: 1992
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Reconfigurable modular machine design for reconfigurable manufacturing environment. / Reconfigurable modular machine design for reconfigurable manufacturing environment.Xing, Bo. 29 October 2010 (has links)
Manufacturing techniques are based on the principles of Flexible Manufacturing and Dedicated Manufacturing for mass production. Reconfigurable Manufacturing Systems (RMS) is a manufacturing system that can provide for Agile Manufacturing (AM). This has lead to research on the concept, design and equipment implementation for RMS. RMS requires three key capabilities: rapid changeover between products, rapid introduction to new products and unattended operation. The relationship between these manufacturing techniques has been investigated. Research has been focused on the research and design of a Reconfigurable Modular Machine (RMM) for RMS. The research has addressed the design of subsystems for RMM by using the generic modular mechatronics control. This approach included modular machine controller hardware, software, mechanical design and generic "plug-and-play" capability, These designs of subsystems allowed for rapid reconfiguration of RMS that increased system efficiency and significantly minimized manufacturing change over downtime. / Manufacturing techniques are based on the principles of Flexible Manufacturing and / Thesis (M.Sc.Eng.)-University of KwaZulu-Natal, Durban, 2006. / Thesis (M.Sc.Eng.)-University of KwaZulu-Natal, Durban, 2006.
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Cordless linear synchronous motor material handling system for computer integrated manufacturing.Lindsay, Craig Vaughn. January 2000 (has links)
Advanced material handling systems' impact on flexible manufacturing systems (FMS) have
increased the efficiency and work rate over conventional manufacturing assemblies. The
interaction of automated guided vehicles (AGVs), roller conveyors and conveyor belts with
robots and machine tools forms highly sophisticated assembly operations.
Whilst material handling in FMS today is conventionally used to transport assembly units
from one work station to another, it does not take an active role in the manufacturing process.
With manufacturers implementing more advanced manufacturing principles to perform agile
manufacturing, there is a growing need to implement "smarter" material handling systems that
would perform essential, integral roles in the assembly process.
This research outlines the development of a cordless linear synchronous motor (CLSM)
material handling system. The CLSM incorporates a permanent magnet courier that moves
without tether restrictions on an integrated reverse air bearing system which eliminates
friction. The CLSM provides a material handling system with enhanced travel, flexibility and
accuracy. The CLSM material handling system is designed to integrate with overhead
manipulators and part feeders to form a comprehensive flexible manufacturing system.
This research covers the 2-D finite element modeling (FEM) used to determine the CLSM's
optimal parameters. The development of the motor windings design and construction, together
with the control system for the CLSM, is also covered. The CLSM novel air bearing system
is outlined and compared to other conventional linear bearing systems. The possible impact
of the CLSM on current manufacturing systems is explored to determine the validity of the
research project and possible further research opportunities. / Thesis (M.Sc.Eng)-University of Natal, Durban, 2000.
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Control of a conveyor system for a reconfigurable manufacturing cellLe Roux, Anro 12 1900 (has links)
Thesis (MScEng)-- Stellenbosch University, 2013. / ENGLISH ABSTRACT: This work entails a study of the control software of transportation systems
for use in recon gurable manufacturing systems (RMSs). Various control approaches
are considered, with the focus on enhancing recon gurability. The
work is unique in the sense that the RMS is designed to manufacture small
parts/products and is meant to be used in developing countries. Manufacturing
systems that can ensure product quality and delivery, are a critical need
in countries where the bulk of manufacturing systems function with manual
labour. RMSs and holonic manufacturing systems (HMSs) are identi ed as
concepts that can potentially compete with manual manufacturing systems.
The competing system must thus have a low initial adoption risk, be able to
adapt to changing product functionality and demands, and have a comparable
throughput rate. IEC61311-3, IEC64199 function block and agent-based
control architectures are evaluated. The control software is tested on an experimental
conveyor system.
The thesis shows that IEC61131-3 and IEC64199 architectures are advantageous
in lower levels of control. IEC64199 function blocks provide human
interface and development tools and simpli es the distribution of control. The
human interface and development tools of IEC64199 function blocks may prove
bene cial in providing system monitoring and rapid low skilled adaptation of
the control system, increasing recon gurability of systems in under-developed
countries. Unfortunately, the low maturity of the development environments
for IEC64199 function blocks is a limitation. It is shown that an IEC64199
function block controller becomes complex as the actuator/sensor count exceed
10. Agent-based systems o er reliable control and powerful communication tools but requires a higher level of expertise than IEC64199 function blocks.
Agent-based systems are proposed for the core high level control. Complex
systems can be controlled with agents and intelligence can be added to control
systems in a recon gurable way. For the recon gurable control of large manufacturing
systems, agent-based control was found to be superior to IEC64199
function blocks. / AFRIKAANSE OPSOMMING: Hierdie werk behels 'n studie in die beheersagteware van vervoerstelsels vir
die gebruik in herkon gureerbare vervaardigingstelsels. Verskeie benaderings
word oorweeg, met die fokus op die verbetering van herkon gureerbaarheid.
Die werk is uniek in die sin dat die herkon gureerbare vervaardigingstelsel ontwerp
is vir die vervaardiging van klein onderdele/produkte en is bedoel vir
die gebruik in die ontwikkelende lande. Vervaardigingstelsels wat die kwaliteit
van die produk en a ewering kan verseker, is 'n kritieke behoefte in die lande
waar die grootste deel van die vervaardiging met handearbeid gedoen word.
Herkon gureerbare vervaardigingstelsels en holoniese vervaardigingstelsels is
geïdenti seer as konsepte wat moontlik kan meeding met die handmatige
produksie-stelsels. Die mededingende stelsel moet dus 'n lae aanvanklike aannemingsrisiko
hê, in staat wees om te kan aanpas by die veranderende produk
funksionaliteit en aanvraag, en 'n vergelykbare deurvloeikoers kan lewer.
IEC61311-3, IEC61499 funksie-blok en agent-gebaseerde beheer argitekture
word geëvalueer. Die beheer sagteware is getoets op 'n eksperimentele vervoerband
stelsel.
Die tesis toon dat IEC61131-3 en IEC61499 argitekture voordelig is in die
laër vlakke van beheer. IEC61499 funksie-blokke voorsien menslike koppelvlak
en ontwikkelings-gereedskap, en vereenvoudig die verspreiding van beheer. Die
menslike koppelvlak en ontwikkelings-gereedskap van die IEC61499 funksieblokke
is moontlik voordelig in die voorsiening van stelselmonitering en vinnige
laag-geskoolde aanpassing van die beheer stelsel. Dit mag dus moontlik
die herkon gureerbaarheid van stelsels, in onder-ontwikkelde lande, verhoog. Die lae vlak van volwassenheid van die ontwikkelingsomgewings vir IEC61499
funksie-blokke verlaag hul bruikbaarheid. Daar word aangetoon dat IEC61499
funksie-blok beheerders baie kompleks raak as die hoeveelheid van aktueerders
en sensors meer as 10 raak. Agent-gebaseerde stelsels bied betroubare beheer,
en kragtige kommunikasie-gereedskap, maar vereis 'n hoër vlak van kundigheid
as IEC61499 funksie-blokke. Agent-gebaseerde stelsels word voorgestel vir die
hoëvlak beheer. Komplekse stelsels kan beheer word met agente en intelligensie
kan bygevoeg word om stelsels te beheer in 'n herkon gureerbare manier.
Dit was gevind dat agent-gebaseerde beheer beter is as IEC61499 funksie-blok
beheer vir die herkon gureerbare beheer van groot vervaardigings stelsels.
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Information technology (IT) in Hong Kong: a case study.January 1989 (has links)
by Chiu, Yu-Wai, Anthony, Chiang, Lily. / Thesis (M.B.A.)--Chinese University of Hong Kong, 1989. / Bibliography: leaves 69-71.
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Study of Fixturing Accessibilities in Computer-Aided Fixture DesignGhatpande, Puja Sudhakar 08 August 2008 (has links)
"Fixtures form an important factor in traditional and modern flexible manufacturing systems, since fixture design directly affects manufacturing quality and productivity. Hence, it is necessary to evaluate quality of fixture design. The fixturing accessibility refers to machining feature accessibility and loading /unloading accessibility. The development of Computer Aided Fixture Design (CAFD) has simplified this task. Fixture design activities include setup planning, fixture planning and fixture configuration design. Fixture design verification comes next. Fixturing accessibility using Computer Aided Fixture Design is part of the verification process and has not received much attention till date. Machining feature accessibility analysis involves the evaluation of possible interference between fixture components and the cutting tool, which moves with pre-programmed tool path, while the loading and unloading accessibility relates to the ease with which the operator attaches/detaches the workpiece from the surrounding manufacturing environment. This research has three main focuses. The first focus is to evaluate machining feature accessibility, by integrating fixture designs in SolidWorks and the NC programming in Esprit. The main goals are evaluation of fixture design for any kind of interference between tool/workpiece/fixtures and enable Esprit to indicate interference, if any. The next step is to modify the fixture design accordingly and thus, finally obtain an interference free fixture design by reiteration. The second and third focuses deal with analysis of loading and unloading accessibility. A simulation based approach is applied to evaluate loading/unloading paths for different workpiece-fixture setups and checking interference in a dynamic mode. Then the third focus is to develop analysis method and criteria of comparisons of fixturing accessibility in different fixture designs. Thus, this research establishes methods of analysis for accessibilities in fixture design. Also, the guidelines for good fixture design will prove to be of great use to both, the beginners as well as the experienced fixture designers in this field. "
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Improving manufacturing systems using integrated discrete event simulation and evolutionary algorithmsKang, Parminder January 2012 (has links)
High variety and low volume manufacturing environment always been a challenge for organisations to maintain their overall performance especially because of the high level of variability induced by ever changing customer demand, high product variety, cycle times, routings and machine failures. All these factors consequences poor flow and degrade the overall organisational performance. For most of the organisations, therefore, process improvement has evidently become the core component for long term survival. The aim of this research here is to develop a methodology for automating operations in process improvement as a part of lean creative problem solving process. To achieve the stated aim, research here has investigated the job sequence and buffer management problem in high variety/low volume manufacturing environment, where lead time and total inventory holding cost are used as operational performance measures. The research here has introduced a novel approach through integration of genetic algorithms based multi-objective combinatorial optimisation and discrete event simulation modelling tool to investigate the effect of variability in high variety/low volume manufacturing by considering the effect of improvement of selected performance measures on each other. Also, proposed methodology works in an iterative manner and allows incorporating changes in different levels of variability. The proposed framework improves over exiting buffer management methodologies, for instance, overcoming the failure modes of drum-buffer-rope system and bringing in the aspect of automation. Also, integration of multi-objective combinatorial optimisation with discrete event simulation allows problem solvers and decision makers to select the solution according to the trade-off between selected performance measures.
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Implementing flow processing with product end of life remanufacturingKhalifa, Sajid January 2013 (has links)
This research focuses on improving the remanufacturing process efficiency by estimating the workstation utilization through identifying percentage of %Blocking and %Waiting on individual workstations within a remanufacturing flow line. It attempts to achieve this aim such that improved use of methods to overcome the effect of variability can be employed. Extensive literature review revealed the requirement of strategies to recover End of Life products due to the introduction and implementation of legislative directives demanding manufacturers to recover the End of Life resources. Upon analyzing the range of product recovery strategies, End of Life product remanufacturing has emerged as an appropriate and suitable strategy to be used since it extends the operational life of existing products without the need for the new resources required when making products. Remanufacturing is a process in which a product is disassembled to component level. Each of the components will be thoroughly examined for defects. Upon identifying defects, they will either be repaired or components will be replaced. This process in turn increases the product life span. However, remanufacturing is not widely used process applied into various industry sectors due to the fact that it is labour intensive and expensive process compared to new products. Although remanufacturing process is in infancy where small number of industry such as Automotive and Aerospace are deriving benefit from it by making effective use of remanufacturing. Ideally, the suitable manufacturing methods i.e. flow processing system, should be used to remanufacture products. However when flow processing is deployed, it is found that there are a number of factors affecting the process that if not tackled, will result in poor performance and poor efficiency of the overall remanufacturing system. This inefficiency is primarily due to the number of sources of variation found in terms of supply, product design, parts specification, operation and demand variability. Further investigation led to the characterizing the remanufacturing variability and identified ways the effect of this variability can be removed or reduced using Lean principles e.g. Single Minute Exchange of Dies and use of an appropriate manufacturing system. Based on the information revised in literature and experimental design, novel equations were developed along with a set of rules that accurately measures the workstation utilization in terms of %Blocking and %Waiting on individual workstation.
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IEC 61131-3-based control of a reconfigurable manufacturing subsystemHoffman, Albert Jakobus 12 1900 (has links)
Thesis (MEng)-- Stellenbosch University, 2014. / ENGLISH ABSTRACT: The South African industry has an increasing need for manufacturing automation. However, the classical form of automation is not cost effective for the low volumes and high variance of products that are produced there. The industry may use the reconfigurable manufacturing system (RMS) concept to improve production of its products. However, industry has been unwilling to adopt the reconfigurable manufacturing systems developed in recent research projects. Due to industry’s hesitance to adopt the control platforms on which reconfigurable manufacturing systems are currently based, the focus of the thesis is on creating a reconfigurable control system using industry accepted technologies.
This research focused on evaluating a Beckhoff embedded PC’s suitability as a station controller that controls a reconfigurable subsystem in an RMS. The control system for the station controller was developed using only the IEC 61131-3 programming languages and the Beckhoff programming software. This control system was evaluated by using it to control a station that is responsible for testing a circuit breaker’s tripping current and time.
The developed control system was based on the ADACOR architecture because of its optimisation capabilities that were necessary to keep the cycle time of the station as low as possible. The design and implementation of the physical configuration and control system of the station is described in this thesis. The station was designed to meet the requirements of both an RMS and the case study.
Because of the limitations of the IEC 61131-3 programming languages, dynamic instantiation of holons is not possible and a method was developed to simulate dynamic task holons. By making use of the embedded PC’s ability to run multiple PLCs at the same time, each type of holon was run in its own PLC thread. The developed control system and station was evaluated by conducting experiments using a laboratory test setup. The evaluation of the developed control system in this thesis proved that an RMS can be created, in the context of station control, using IEC 61131-3 and industry accepted technologies, if a hardware platform is used that allows multiple PLCs to be run in individual threads. The control approach that was created in this thesis can be used to create station control systems that offers optimised cycle times, the benefits of an RMS and the benefits of industry accepted technology. / AFRIKAANSE OPSOMMING: Die Suid-Afrikaanse bedryf het 'n toenemende behoefte aan geoutomatiseerde vervaardiging. Die klassieke vorm van outomatisasie is egter nie koste effektief vir die lae volumes en hoë variansie van produkte wat in Suid Afrika geproduseer word nie. Die bedryf kan moontlik die konsep van 'n herkonfigureerbare vervaardigingstelsel (HVS) gebruik om vervaardiging te outomatiseer. Die bedryf is egter nie bereid om die herkonfigureerbare vervaardigingstelsels wat in onlangse navorsingsprojekte ontwikkel is, te aanvaar nie. As gevolg van die bedryf se huiwering om die beheerplatforms waarop herkonfigureerbare vervaardigingstelsels tans gebaseer word, te aanvaar, is die fokus van die tesis om industrie-aanvaarde tegnologie te gebruik om ‘n herkonfigureerbare beheerstelsel te skep.
Hierdie navorsing fokus op die evaluering van 'n “Beckhoff embedded PC” se geskiktheid as 'n stasiebeheerder van 'n herkonfigureerbare substelsel in 'n HVS. Die beheerstelsel vir die stasie beheerder is ontwikkel deur slegs van die IEC 61131-3 programmeringstale en die Beckhoff programmering-sagteware gebruik te maak. Hierdie beheerstelsel is geëvalueer deur dit op die beheer van 'n stasie wat verantwoordelik is vir die toets stroombrekers, toe te pas.
Die beheerstelsel was gebaseer op die ADACOR argitektuur as gevolg van die optimeringsvermoëns wat noodsaaklik was om die siklustyd van die stasie so laag as moontlik te hou. Die ontwerp en implementering van die fisiese konfigurasie en beheerstelsel van die stasie word in hierdie tesis beskryf. Die stasie was ontwerp om aan die vereistes van beide 'n HVS en die gevallestudie te voldoen.
As gevolg van die beperkings van die IEC 61131-3 programmeringstale, is dinamiese instansiëring van holons nie moontlik nie, en 'n metode is ontwikkelom dinamiese taakholons na te boots. Deur gebruik te maak van die "embedded PC" se vermoë om meervoudige PLCs terselfdetyd te hanteer, kan elke holon tipe in sy eie "thread" loop. Die ontwikkelde stelsel en die stasie is geëvalueer in 'n laboratorium deur middel van eksperimente. Die evaluering van die beheerstelsel in hierdie tesis bewys dat 'n HVS geskep kan word, in die konteks van ‘n stasiebeheerder, deur IEC 61131-3 en tegnologie wat wyd in die industrie aanvaar word, te gebruik mits die hardeware-platform wat gebruik word toelaat dat verskeie PLCs terselfde tyd op een beheerder kan loop. Die beheerbenadering wat geskep is in hierdie tesis kan gebruik word om stasie- beheerstelsels te skep wat optimale siklus tye, die voordele van 'n HVS en die voordele van industrie-aanvaarde tegnologie bied.
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