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1 – 10 of 173Ronald Brian Jennings and Glen Bright
Manufacturers faced with small production runs often require multiple machine changeovers per shift. Vision control of machinery offers a cost‐effective solution to this problem…
Abstract
Manufacturers faced with small production runs often require multiple machine changeovers per shift. Vision control of machinery offers a cost‐effective solution to this problem. Manufacturers are able to introduce diverse products, randomly, to a process line during the same production run, using reasonably priced industrial electronic equipment incorporating vision technology. A vision controlled polyurethane dispensing machine has been designed, manufactured and commissioned to substantiate this theory. An image of a moat, recessed into a mould, is captured by means of a CCD camera, resulting in a dispensing path being transferred to a microprocessor. The analogue signal is converted to a digital signal that pre‐sets a path for the two‐axis motion controller, capable of performing interpolation, to follow. A polyurethane mixing machine receives the same digital signal which sets the dispensing rate and shot size. Polyurethane is dispensed into the moat to form a seal between the filter media and the air‐filter housing. A summary of the design, implementation and results of the project is outlined and described.
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Automated visual inspection is vital in the production of manufactured products acceptable to world market standards. The volatile nature of the consumer markets is placing…
Abstract
Automated visual inspection is vital in the production of manufactured products acceptable to world market standards. The volatile nature of the consumer markets is placing increased emphasis on manufacturers to produce cheaper products of higher quality. With increasingly more manufacturers implementing advanced manufacturing principles to perform agile manufacturing, the need for cost‐effective, automated quality control has been highlighted. This paper proposes a cost‐effective, automated, visual inspection system capable of performing in‐process verification in the flexible manufacturing environment.
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Fentahun Moges Kasie and Glen Bright
This paper aims to propose an intelligent system that serves as a cost estimator when new part orders are received from customers.
Abstract
Purpose
This paper aims to propose an intelligent system that serves as a cost estimator when new part orders are received from customers.
Design/methodology/approach
The methodologies applied in this study were case-based reasoning (CBR), analytic hierarchy process, rule-based reasoning and fuzzy set theory for case retrieval. The retrieved cases were revised using parametric and feature-based cost estimation techniques. Cases were represented using an object-oriented (OO) approach to characterize them in n-dimensional Euclidean vector space.
Findings
The proposed cost estimator retrieves historical cases that have the most similar cost estimates to the current new orders. Further, it revises the retrieved cost estimates based on attribute differences between new and retrieved cases using parametric and feature-based cost estimation techniques.
Research limitations/implications
The proposed system was illustrated using a numerical example by considering different lathe machine operations in a computer-based laboratory environment; however, its applicability was not validated in industrial situations.
Originality/value
Different intelligent methods were proposed in the past; however, the combination of fuzzy CBR, parametric and feature-oriented methods was not addressed in product cost estimation problems.
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Fentahun Moges Kasie, Glen Bright and Anthony Walker
The purpose of this paper is to propose a decision support system (DSS) that stabilizes the flow of fixtures in manufacturing systems. The proposed DSS assists decision-makers to…
Abstract
Purpose
The purpose of this paper is to propose a decision support system (DSS) that stabilizes the flow of fixtures in manufacturing systems. The proposed DSS assists decision-makers to reuse or adapt the available fixtures or to manufacture new fixtures depending upon the similarity between the past and new cases. It considers the cost effectiveness of the proposed decision when an adaptation decision is passed.
Design/methodology/approach
The research problem is addressed by integrating case-based reasoning, rule-based reasoning and fuzzy set theory. Cases are represented using an object-oriented (OO) approach to characterize them by their feature vectors. The fuzzy analytic hierarchy process (FAHP) and the inverse of weighted Euclidean distance measure are applied for case retrieval. A machining operation is illustrated as a computational example to demonstrate the applicability of the proposed DSS.
Findings
The problems of fixture assignment and control have not been well-addressed in the past, although fixture management is one of the complex problems in manufacturing. The proposed DSS is a promising approach to address such kinds of problems using the three components of an artificial intelligence and FAHP.
Research limitations/implications
Although the DSS is tested in a laboratory environment using a numerical example, it has not been validated in real industrial systems.
Practical implications
The DSS is proposed in terms of simple rules and equations. This implies that it is not complex for software development and implementation. The illustrated numerical example indicates that the proposed DSS can be implemented in the real-world.
Originality/value
Demand-driven fixture retrieval and manufacture to assign the right fixtures to planned part-orders using an intelligent DSS is the main contribution. It provides special consideration for the adaptation of the available fixtures in a system.
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Fentahun Moges Kasie, Glen Bright and Anthony Walker
This paper aims to propose a theoretical decision support framework, which integrates artificial intelligence (AI), discrete-event simulation (DES) and database management…
Abstract
Purpose
This paper aims to propose a theoretical decision support framework, which integrates artificial intelligence (AI), discrete-event simulation (DES) and database management technologies so as to determine the steady state flow of items (e.g. fixtures, jigs, tools, etc.) in manufacturing.
Design/methodology/approach
The existing literature was carefully reviewed to address the state of the arts in decision support systems (DSS), the shortcomings of pure simulation-based and pure AI-based DSS. A conceptual example is illustrated to show the integrated application of AI, simulation and database components of the proposed DSS framework.
Findings
Recent DSS studies have revealed the limitations of pure simulation-based and pure AI-based DSS. A new DSS framework is required in manufacturing to address these limitations, taking into account the problems of flowing items.
Research limitations/implications
The theoretical DSS framework is proposed using simple rules and equations. This implies that it is not complex for software development and implementation. Practical data are not presented in this paper. A real DSS will be developed using the proposed theoretical framework and realistic results will be presented in the near future.
Originality/value
The proposed theoretical framework reveals how the integrated components of DSS can work together in manufacturing in order to determine the stable flow of items in a specific production period. Especially, the integrated performance of case-based reasoning (CBR) and DES is conceptually illustrated.
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Drew van der Riet, Riaan Stopforth, Glen Bright and Olaf Diegel
This paper aims to explore the electronic design of the Touch Hand: a low-cost electrically powered prosthetic hand. The hand is equipped with an array of sensors allowing for…
Abstract
Purpose
This paper aims to explore the electronic design of the Touch Hand: a low-cost electrically powered prosthetic hand. The hand is equipped with an array of sensors allowing for position control and haptic sensation. Pressure sensors are used on the fingertips to detect grip force. A temperature sensor placed in the fingertip is used to measure the contact temperature of objects. Investigations are made into the use of cantilever vibration sensors to detect surface texture and object slippage. The hand is capable of performing a lateral grip of 3.7 N, a power grip of 19.5 N and to passively hold a weight of up to 8 kg with a hook grip. The hand is also tested on an amputee and used to perform basic tasks. The amputee took 30 min to learn how to operate the hands basic gripping functions.
Design/methodology/approach
Problems of previous prosthetic hands were investigated, followed by ways to improve or have similar capabilities, yet keeping in mind to reduce the price. The hand was then designed, simulated, developed and then tested. The hand was then displayed to public and tested with an amputee.
Findings
The Touch Hand’s capabilities with the usage of the low-cost materials, components and sensory system was obtained in the tests that were conducted. The results are shown in this paper to identify the appropriateness of the sensors for a usage while the costs are reduced. Furthermore, models were developed from the results obtained to take into account factors such as the non-slip material.
Research limitations/implications
The research was restricted to a US$1,000 budget to allow the availability of a low-cost prosthetic hand.
Practical implications
The Touch Hand had to have the ability to supply the amputee with haptic feedback while allowing the basic grasping of objects. The commercial value is the availability of an affordable prosthetic hand that can be used by amputees in Africa and other Lower-Income countries, yet allowing a more advanced control system compared to the pure mechanical systems currently available.
Social implications
The Touch Hand has the ability to give amputees affected in war situations the ability to grasp objects in a more affordable manner compared to the current available options. Feedback from amputees about the current features of the Touch Hand was very positive and it proves to be a way to improve society in Lower-Income countries in the near future. A sponsorship program is being developed to assist amputees with the costs of the Touch Hand.
Originality/value
The contributions of this research is a low-cost prototype system than can be commercialized to allow amputees in the Lower-Income countries to have the ability of a prosthetic hand. A sensory system in the hand is also explained which other low-cost prosthetic hands do not have, which includes temperature, force and vibration. Models of the sensors used that are developed and calibrated to the design of the hand are also described.
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Fentahun Moges Kasie and Glen Bright
This study aims to propose a decision support system (DSS) that performs a decision-based part-fixture assignment and fixture flow control in planned production periods.
Abstract
Purpose
This study aims to propose a decision support system (DSS) that performs a decision-based part-fixture assignment and fixture flow control in planned production periods.
Design/methodology/approach
The principal approaches were fuzzy case-based reasoning (FCBR) and discrete-event simulation (DES). Besides, the fuzzy analytic hierarchy process (FAHP), an object-oriented (OO) method and a fuzzy weighted Euclidean distance were used to support the decision-making process.
Findings
It shows that integrating FCBR and DES systems is a promising approach to address part-fixture planning problems. The FCBR subsystem proposed various stable numbers of fixtures as scenarios. The DES model analyzed the future performances of these scenarios and identified the best alternative.
Research limitations/implications
The DSS was tested in laboratory environments using a numerical analysis; however, it was not validated in industrial situations.
Originality/value
The synergy of integrating FCBR and DES systems was not exploited in the past in part-fixture assignment and fixture flow control problems.
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Shaniel Davrajh and Glen Bright
Quality control and part inspection add no monetary value to a product, yet are essential processes for manufacturers who want to maintain product quality. Mass‐produced custom…
Abstract
Purpose
Quality control and part inspection add no monetary value to a product, yet are essential processes for manufacturers who want to maintain product quality. Mass‐produced custom parts require processes that are able to perform high frequency of inspection, whilst providing rapid response to unanticipated changes in parameters such as throughputs, dimensions and tolerances. Frequent inspection of these parts significantly impacts inspection times involved. A method of reducing the impact of high‐frequency inspection on production rates is needed. This paper addresses these issues.
Design/methodology/approach
This paper involves the research, design, construction, assembly and implementation of an automated apparatus, used for the visual inspection of moving custom parts. Inspection occurred at user‐defined regions of interest (ROIs). Mechatronic Engineering principles are used to integrate sensor articulation, image acquisition and image‐processing systems. The apparatus is tested in a computer‐integrated manufacturing (CIM) cell for quantifying results.
Findings
Specified production rates are maintained whilst performing high frequencies of inspection, without stoppage of parts along the production line.
Research limitations/implications
The limitations of these results lie in the fact that they are suited only to the speed of the CIM cell. Higher inspection rates may be achieved, and changes in the design may be required in order to make the apparatus more suitable to industrial applications.
Practical implications
The paper shows that it is possible to maintain high standards of quality control without significantly affecting production rates.
Originality/value
Current research does not focus on maintaining production rates whilst inspecting custom parts. The use of ROI inspection for moving custom parts is a relatively new concept.
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Olaf Diegel, Glen Bright and Johan Potgieter
The integration of humans and machines can be achieved using Bluetooth ubiquitous networks. Ideally, the interface between users and machines should be completely seamless and…
Abstract
The integration of humans and machines can be achieved using Bluetooth ubiquitous networks. Ideally, the interface between users and machines should be completely seamless and transparent. A user should not need to take any physical action to have a machine react to commands. A novel application area for Bluetooth communication technology is being developed in the Massey University Smart House project, in New Zealand. The creation of a Bluetooth ubiquitous network allows the house users to be tracked and monitored throughout the house. Their specific preferences or needs can automatically be taken care of by a control computer. This paper outlines and describes this seamless application.
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Shaniel Davrajh and Glen Bright
Production of a high variety of products introduces complexities in the quality processes involved in a manufacturing system. Previous methods of quality assurance and control are…
Abstract
Purpose
Production of a high variety of products introduces complexities in the quality processes involved in a manufacturing system. Previous methods of quality assurance and control are not sufficient to manage the quality characteristics that are significant to each customer. Research into quality management for these environments has been isolated and segmented. No framework exists to holistically manage product quality within an unstable manufacturing environment. This paper seeks to propose a method of holistically managing product quality in a manufacturing environment with high customer input and product variety. The development of a reconfigurable inspection apparatus is discussed as a technological requirement for performing the quality control aspect of the management system.
Design/methodology/approach
The quality requirements of modern manufacturing systems were established. The required flow of information for an advanced quality management system was proposed and compared to the information flow in a traditional quality management system. The developed reconfigurable inspection apparatus was tested by performing an inspection of a product configuration within a part family of torches. Commercial products were used for the construction of the apparatus, including the electrical and software aspects. A commercially available simulation package was used to simulate the effects of a random customer order on production flow whilst implementing the developed apparatus.
Findings
Modular inspection equipment would prove essential to the implementation of quality control when considering advanced manufacturing environments. An overall management system is also needed for the verification of product quality as per individual customer requirements. Quality needs to be integrated as per TQM principles.
Research limitations/implications
Traditional quality control tools may not always be applicable for unstable market demand. The research indicated the required progression of quality systems to successfully manage the quality for advanced manufacturing. The widespread availability of commercial components for the inspection apparatus verified the shift in supplier focus to meet the needs of shifting manufacturing requirements.
Practical implications
The proposed approach to assure and control quality, as well as the researched inspection apparatus, provided the capability of being implemented in a manufacturing environment that involves production of a variety of products as opposed to being limited to one part family. The use of modular mechanical, electrical and software components will ease the implementation of reconfigurable inspection stations into existing manufacturing setups.
Originality/value
Research indicated that quality systems need to be further developed for assuring and controlling product quality of products with high customer input. No system existed that could holistically consider the quality requirements of a product from design to delivery.
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