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Item Model for developing a feature recogntion system for a reconfigurable bending press machine.(Elsevier, 2017-01-01) Murena, Eriyeti; Mpofu, Khumbulani; Trimble, John; Gwangwava, NormanSheet metal products are often designed without a systematic consideration of downstream product development requirements, such as process planning, manufacturability, production scheduling and manufacturing optimization. This can often result in a lot of expensive and time consuming reworks. Consequently, it affects the quality, cost and delivery time of the product. In this paper, a framework for developing a web - based feature recognition system (FRS) has been proposed to recognise bending features on a reconfigurable bending press machine (RBPM). The research explores the current literature and design approaches used to develop feature recognition systems in the current manufacturing industries. This model will help to offer a suitable method for designing a web based feature recognition system for sheet metal bending using RBPMs. This model will be applied to feature recognition systems in other manufacturing industries. The model consists of the integrated platform system, information model, part model, geometric modelling and the feature model. The proposed models will aid the designer right at the design stage with useful design and the feature recognition system. The designer will be able to relate process technology to product design instead of specifying the geometric definition alone. Design of these models will provide a more convenient design environment and an easier way to integrate CAD/ CAM activities. After developing the model the designer will be able to use the CAD software to develop patterns, interpret drawings and transfer dimensions to sheet materials and sections to meet the required specification.Item Framework for the development of a new reconfigurable Guillotine shear and bending press machine.(Elsevier, 2017-01-01) Sibanda, Vennan; Mpofu, Khumbulani; Trimble, JohnIn today’s manufacturing world, consumer satisfaction is difficult to achieve owing to the dynamic and continuous changes in their requirements and the rapid change in product designs. Research has been carried out on several innovations addressing this problem with various machine designs having been produced to deal effectively with the dynamic customer needs. Reconfigurable manufacturing systems (RMSs) and machines (RMTs), having superseded the dedicated manufacturing lines (DMLs) with dedicated machine tools (DMTs); and flexible manufacturing systems (FMSs) with their machines (FMTs), have led to a new era that takes the best aspects of both DMLs, FMSs and machines to conceive a new manufacturing system, RMS and RMTs that satisfy the dynamic nature of customer requirements. The aim of this paper is to present a structured framework that will optimise the development process of a new reconfigurable guillotine shear and bending press machine to be used in sheet metal work. The framework provides a guide for designers and manufactures of sheet metal machines in developing the new machine. To develop the framework, research used various tools such as reviewing existing literature on RMSs & RMTs, DMLs & DMTs, FMSs & FMTs and expected product change responsiveness. Research also explored literature on the development of machine modules for reconfigurable machines and reconfigurable technology systems. The framework seeks to provide a structured approach towards the machine development by highlighting important steps to be taken and various aspects to be considered. The results give a framework that will guide the development of a reconfigurable guillotine shear and bending press machine tool that can be configured and reconfigured to enable cutting and bending of varying sheet metal products by a single machine with dual functionality.Item Sustainability of additive manufacturing for the South African aerospace industry: A business model for laser technology production, commercialization and market prospects.(Elsevier, 2018-01-01) Oyesola, Moses; Mathe, Ntombi; Mpofu, Khumbulani; Fatoba, SamuelEver changing products, technology and competition make manufacturing a challenging task with respect to responding to market opportunities. A key technology exploited for revolutionary change in the phase of manufacturing competitiveness is the additive manufacturing techniques. Additive manufacturing (AM) is a category of technologies, which is fast shifting from mere resource base to a knowledge base, transitioning from prototyping to manufacturing of end usable parts with defined mechanical properties. In South African industrialization context, technology development for value proposition is an encouraged phenomenon. This is being realized through the South African government’s investment in research and equipment funding to science council and academia focusing on the full AM value chain for the aerospace and medical industries. However, despite the skills in the research and development space of AM, laser technology remain an unconventional process that lacks knowledge in terms of how the production techniques can be commercialized. The aim of this study is to evaluate technological capabilities that informs industrial manufacturing setup, and create a business prospects for the laser-based additive manufacturing segment of South Africa.Item Flexible and adaptable learning factrories for the rail car manufacturing industry.(Elsevier, 2018-01-01) Maheso, Matilda Nkateko; Mpofu, Khumbula; Sibanda, VennanAs the need for a skilled labor force in the manufacturing domain increases in South Africa, particularly the rail car manufacturing industry it is upon academia to provide engineers who will quickly adapt and function upon employment for this industry to become a success. The challenge faced in education to produce relevant future employees has been struck by filling in the gap that causes misalignment between academia and industry. Learning factories however play a critical role in ensuring the production of future engineers from academia to the workplace. The main challenge is the mismatch between industry and academia and there is a need to bridge that gap. The aim of the research therefore is to develop a flexible learning factory that can be used in bridging the gap between institutions of higher learning and railcar manufacturing activities. A critical review on learning factories and reconfigurable systems was made to identify the gap and develop the learning factory that addresses the gap. Also a visit to industry complemented the research through one on one contact with railcar manufactures. The results show a developed learning factory that can be used in equipping graduates with the knowledge required in industry, particularly the railcar manufacturing industry. A specific area in the railcar (bogie) was identified as the key area that was considered in the development.Item Human-Robot collaboration in a small scale rail industry: demanufacturing operations.(Elsevier, 2018-06-10) Phuluwa, Humbulani Simon; Khumbulani, MpofuTrains car production around the globe has been happening for centuries in the developed and developing countries. However, components recovery of the end-of-life train cars is difficult to do without negatively affecting the quality and productivity of demanufacturing operations. South African rail industry lacks demanufacturing industries that focus on material recovery of end-of-life train cars. This study surveyed literature on robotics and their collaboration with humans in demanufacturing activities and identify key factors that can be useful in demanufacturing operations in a small-scale rail industry. This study used process charts to study and understand robotics collaboration with humans focusing on demanufacturing operations. This study intended to develop a framework for human’s collaboration with robotics in small-scale demanufacturing operations rail industry.Item Machine morphology in reconfigurable machine tools.(Elsevier, 2012-05-23) Mpofu, KhumbulaniMachine morphology within the reconfigurable machine tool environment is considered in this article in a bid to address the configurations and reconfigurations that will be needed to meet the uncertain and unpredictable demands in the market. This paper proposes a hierarchical classification mechanism for machine structures, these structures derive from module combinations where symbology is utilized to represent the machines and these symbols can be used in the configuration process. Authors envisage this method to be relevant in the combinatorial problem reconfigurable environments face.Item Concept development for reconfigurable bending press tools’ (RBPTs) modules using a novel methodology.IFAC Proceedings Volumes(Elsevier, 2012-05-22) Gwangwava, N.; Mpofu, K.; Tlale, N.; Yu, Y.This paper outlines the development of reconfiguration concepts for new optimized reconfigurable bending press tools (RBPTs) using a novel methodology. The researchers propose the reconfiguration concepts with the main objective of optimizing press brake utilization as determined by the set up bed length, multiple parts bent per set up, bending force, stroke height, bending technology, set up and r ramp up time, and number of strokes. The procedure for RBPT concept development include the construction of a first house of quality (HOQ1) based on the quality function deployment (QFD) technique. Research done by the authors identified two main objectives of RBPT design which are geometric transformation and productivity adjustment. The first can be further split into two reconfiguration categories, horizontal reconfigurability and vertical reconfigurability. These are used to derive reconfiguration needs for the RBPTs. Identification of the RBPT modules is done using the function driven object oriented (FUDOO) methodology. This involves identification of the primary function of a typical RBPT and cascading it down to sub functions and terminal functions subsequently. Reconfiguration concepts are then developed for each identified RBPT module. Length reconfiguration is proposed to extend or shorten the bed and ram span. This will be accomplished by introducing standard modules for the bed and ram beams optimally designed to withstand deflection during bending.Item Review of the status of reconfigurable manufacturing systems (RMS) application in South Africa mining machinery industries.(Elsevier, 2014-01-01) Makinde, O.A.; Mpofu, K.; Popoola, A.P.I.Reconfigurable Manufacturing Systems (RMS) has been used extensively in different industries and companies to produce modularized, customized, flexible and scalable products. Due to the variations in the mining equipment users demand, dynamic nature and complexities in the mining manufacturing environment in terms of space available, kind of mining operations and the risks involved, RMS have been extensively used to produce different mining equipment product varieties of high adaptability, low repair cost and minimum maintenance cost in order to meet customers satisfaction. Further on, this paper explores on various literature review in relation to reconfigurable manufacturing system concepts, architectural design characteristics, control capabilities and its role in mining machinery industries, and the potential future of this RMS in South Africa mining machinery industries. Reconfigurable Manufacturing Systems has been used in mining machinery industries to manufacture Load Haul Dump (LHD) trucks, multiple drilling bits such as the tricone bits, screen mesh of different aperture sizes which has contributed immensely to the 15.3% GDP achieved by the manufacturing sector in South Africa. Global high mineral demand is a positive indicator for great future in this industry if RMS is fully harnessed, utilized and applied in this sector. Furthermore, a newly designed flexible, cheap, versatile and reconfigurable vibrating screen by Industrial Engineering Department, Tshwane University of Technology, Pretoria will also serve as a catalyst to catapult the mineral processing industries to its peak.Item Comparison of weighted decision matrix, and analytical hierarchy process for CAD design of reconfigurable assembly fixture.(Elsevier, 2014-01-01) Olabanji, O. M.; Mpofu, K.Reconfigurable assembly fixtures are major components of a reconfigurable assembly system. They are precision components which require an intensive design process due to their usage and interaction with other components in the assembly system. Concept selection is a time consuming activity in the engineering design process, because it involves decision making and consideration of multiple factors. A computer aided design approach of four concepts was developed for a reconfigurable assembly fixture, based on functional requirements, cost, and manufacturability. The weighted decision matrix and analytical hierarchy process was used to compare these concepts. The decision criteria and evaluation technique used during this concept selection process is novel thus calling for its application in design of engineering components. The results of the two methods are presented graphically and the variations in the results obtained are used to judge the suitable method among both processes for the optimal design.Item Inventory management framework to minimize supply and demand mismatch on a manufacturing organization.(Elsevier, 2015-01-01) Matsebatlela, M.G.; Mpofu, K.There is a problem of excessive inventory in a Manufacturing Company, situated in South Africa. In this study an Inventory Management Framework (IMF) was developed. Quantitative content analysis was used to collect data. Statistical tools were used to select the fiscal year with the vast data variation for data analysis for this study. The results reveal that uncertainties and lot sizing inventory results in excessive inventory and not having a collaborated and integrated Supply chain Management also results in a mismatch of supply and Demand. IMF is proposed in this paper to minimize the impact of the mismatch.Item Achieving sustainability in manufacturing using robotic methodologies.(Elsevier, 2017-01-01) Ogbemhe, J.; Mpofu, K.; Tlale, N.S.There has been a recent push in robotics globally. This work makes an attempt at exploring the role of robotics in achieving sustainability in manufacturing. Its describes the advancement made so far in applying robots to manufacturing- welding shot blasting, painting, and so forth, within the sustainability framework. Factors militating against the sustainable economic model are addressed. New methodologies are much needed to bridge the knowledge gap between research and industry, regarding the design and implementation of robotic applications in manufacturing and also a skill-gap and skill shortages framework. The adoption of new technologies like Robotic Operating Systems (ROS), in the approaches to the design of industrial robots, could enhance sustainability in the use of robots in manufacturing at a reduced cost.Item Development of a prototype test rig for leak detection in pipelines.(Elsevier, 2019-01-01) Daniyan, I. A.; Dahunsi, O. A.; Oguntuase, O. B.; Daniyan, O. L.; Mpofu, K.Over the years, the conventional method most industries use in detecting pipeline leakages is called the pressure test. This method is too stressful and even takes longer time to locate the exact location of the leak. This work studies the unconventional way of detecting oil leakage with a view of designing a model control system to detect leak without human intervention, both on-the-job and off the job. In this work, a prototype test rig was designed and fabricated. Its components include pipes and piping components, air valve, adaptor, barometer, MxF Socket, non-return valve, pressure relief valve, and reducers. The rig was fabricated based on its 3D architecture using solid works application tool. The rig has four different flow line with pressure sensors and gauges mounted on each line. Pressure transducers on the rigs keeps monitoring the pressure inside the rig and immediately it detects a pressure drop below the threshold value, the micro controller based on the programmed code on it communicates with the SMS module which subsequently sends an SMS alert to the programmed phone number and gives the location of the leak as well as the actual pressure in that location. Thus, this study enhances quick leak detection, thus, gainfully helps to minimize losses during on the job operation in the case of spills and saves time in locating the exact point of leakage.Item Investigating the thermal properties of carbon steel STKM13a for the welding assembly of rail car suspension system.(Elsevier, 2019-01-01) Daniyan, I. A.; Mpofu, K.; Adeodu, A.O.The welding operation is a complex process, which requires appropriate control of process parameters as well as good understanding of the mechanical and thermal properties of the weld material. In this study, the effect of the thermal properties of carbon steel STKM13A for the welding assembly of rail car suspension system was investigated using the Simufact software in order to minimize weld distortion, structural defects and optimize the welding process, weld sequence, paths and clamping concept. The welding parameters for the simulation process of the welding assembly of the suspension system of the rail car are as follow: voltage (24 V), current (220 A), speed (0.01 m/s), arc length (0.05 m) and efficiency (0.9). This serves as the input parameters into Simufact software version 7.2 for the simulation of the arc welding process at ambient temperature of 25℃ to melting temperature of 1500℃. Also, in order to study the effect of thermal conductivity on the welding process, the thermal modelling was carried out at room temperature to melting temperatures (25-1500℃ ) using the values of three critical parameters namely; specific heat (700 J/kgK), thermal conductivity (40 W/m.K) and coefficient of thermal expansion (1.5 × 10−5 𝐾𝐾−1) as input parameters into the software. The analysis of results obtained indicate that the three parameters are critical as they affect welding processes significantly hence should be controlled to promote safe, reliable and efficient welding processes.Item Business model for integrating energy efficiency performance in manufacturing industries: Railcar case study.(Elsevier, 2019-01-01) Gamede, Gabisile Buyiswa; Mpofu, Khumbulani; Adenuga, Olukorede TijaniThe strong environmental policies, market demand and environmental sustainability has affected industrial firms, and forced them to create sustainable energy solutions. Improving energy efficiency is a key driver for sustainability, especially in high energy intensive industries that includes rail car manufacturing, which calls for implementation of energy efficiency initiatives in managing energy consumption, thus reducing energy costs and environmental pollution. The article proposes a business model that can be used by Energy Service Companies (ESCos) in creating, delivering and capturing value of energy (electricity) using canvas methodology.Item Continuous trajectory planning for welding of complex joints using bezie curve.(Elsevier, 2019-01-01) Ogbemhe, J.; Mpofu, K.; Tlale, N.S.Sustainable manufacturing is now extensively cited in the literature; robotic technologies play a vital role in achieving it. The motivation for the use of industrial robots is mainly for their ability to execute programmed, tedious tasks, and to assist workers to perform boring and dirty jobs with the sole aim of advancing productivity and efficiency. For industrial robots to contribute optimally to sustainable manufacturing, trajectory planning plays a key role in achieving this goal. In this paper, a Frenet Serret vectors are used to design a trajectory planning scheme for welding of complex joints, found in railcar manufacturing by using robotic welding application. The geometry of the complex path produce during arc welding is modelled as a Bezier spatial curve. An eight-order septic curve is used to interpolate the trajectory for a continuous motion a priori found in arc welding applications. The objective of the industrial robot manipulator is to follow a prescribed trajectory in the presence of imposed velocity and acceleration continuity constraints. Simulation is carried out to prove the validity of the proposed scheme.Item Web-based process planning system concept selection using Weighted Decision Matrix and Analytical Hierarchy Process: A case study of sheet metal bending operations.(Elsevier, 2019-01-01) Murena, Eriyeti; Mpofu, Khumbulani; Makinde, Olasumbo; Trimble, John; Wang, XiThe demand for sheet metal bending products has pushed the sheet metal industry to adopt new process planning approaches that can transform the existing systems in order to improve efficiency and reduce costs during product design and manufacture. Sheet metal industries are still using traditional system planning methods, which have limited capacity to respond to rapid changes in market requirements. In light of this, this paper proposes a suitable web-based process planning system that can be used to effectively bend varieties of sheet metal products using various bending press machines. Three web-based process planning system concepts were formulated in this study and evaluated using various criteria. The result of the Weighted Decision Matrix (WDM) and the Analytical Hierarchy Process (AHP) analyses revealed that web-based process planning system concept Y with a cumulative assessment score of 1.90 and a priority assessment score of 0.637 is the suitable web-based process planning system that could be used to effectively bend varieties of sheet metals. This evaluation approach serves as a useful information for system designers in other manufacturing sectors, to select suitable systems capable of effectively carrying out their operations.Item Integrating Product-Service Systems into the manufacturing industry: Industry 4.0 perspectives.(Elsevier, 2019-01-01) Shihundla, Trevor Bogani; Mpofu, Khumbulani; Adenuga, Olukorede TijaniIndustry 4.0 is the current trend in the technologies used in exchange of data in manufacturing. Product-service system is a concept that provides self-aware and self-learning machines, and consequently improve overall performance and maintenance management. Companies continually strive to increase production, but in recent years, the effects of this effort have demonstrated that provision of products alone with less resilient technology-enabled service industry is insufficient to remain competitive. The importance of leveraging flexibility and capabilities offered by cloud computing is inevitable, but adapting prognostics and health management algorithms to efficiently implement current data management technologies was research and develop in this study. In this paper, we present an integrated product-service system as a potential concept from a life-cycle perspective to reduce disruption, costs and associated services such as autonomous maintenance, through exchange of data to understand equipment degradation using sensors application, to aid timely services intervention for manufacturing processes transformation. The results is the knowledge base servitude backed by machine clusters generated data for different working conditions to improve operational efficiency using Cloud IoT to connect, process, store, and analyse data on the dashboard, locally and in the cloud for future health assessment.Item Application of robotics in rail car manufacturing learning factory: A case of welding complex joints.(Elsevier, 2019-01-01) Ogbemhe, John; Mpofu, Khumbulani; Tlale, Nkgatho; Ramatsetse, BoitumeloThe use of a learning factory creates a platform for putting to use research innovations, directly into industrial practice. Railcar manufacturers are migrating to fully automated and innovative solutions with industrial welding robot systems playing a pivotal role in the paradigm shift for tasks such as the production of bogie frames and their components. Furthermore, the skills required for bringing about the automation of dangerous and dirty task in the railcar industry are scarce. There is pressure from stakeholders on how researchers and manufacturers can be more efficient in developing a theoretical and practical application framework for a real-time production in the railcar manufacturing industry. Therefore, researchers must look for ways to transfer and demonstrate the application of robotics research in the shop floor with causing disruptions. In addition, there is a need to develop appropriate and customised skill transfer solutions for both smaller and large business owners especially for tasks that are boring for humans. This paper presents an offline-line scheme for building robotic arc welding cell using device task definition and workbenches of the Delmia V5 Robotics, within the learning factory framework.Item Energy efficiency analysis modelling system for manufacturing in the context of industry 4.0.(Elsevier, 2019-01-01) Adenuga, Olukorede Tijani; Mpofu, Khumbulani; Ramatsetse, Innocent BoitumeloEmerging rise in power costs and sustainability of the available energy has prompted industries to seek alternative solutions that could address energy consumption as the second highest contributor to business expenditure compared to salaries and rentals. Regrettably, numerous industries are still reluctant to benefit from the opportunities that exist on energy saving and consciousness, due to inadequate knowledge on energy management, resources and tools to monitor the losses. Based on these facts, this paper proposed the Energy Efficiency Analysis Modelling System (EEAMS) as a tool to provide an estimate of energy costs using rail car manufacturing plant load profiles as a case study, to provide consumer-oriented analysis to produce first-cut energy efficient program baseline costs. Furthermore, the exploration of energy efficiency baseline may benefit the life cycle cost of the overall proposed facility through energy efficient means of production, and continuous improvement practises in big data analytics towards reduction of energy costs significantly through integration of energy efficiency software (EES). To achieve this, a bottom-up approach methodology was adopted, using information on energy cost as a baseline to allow centralisation and cloud hosting of data through a web-based interacting energy efficiency sustainability framework platform, to determine the economic impacts of energy measurement and verification on energy consumption and environment. Minimum Efficiency Performance Standards established to provide opportunities for the support of the rail car manufacturing company to prepare themselves for the issuing of certificates for energy management (ISO50001).Item A learning factory concept for skills enhancement in rail car manufacturing industries.(Elsevier, 2019-01-01) Maheso, Nkateko; Mpofu, Khumbulani; Ramatsetse, BoitumeloRail manufacturing industries plays a key role in various countries by developing cost effective transportation solutions that could be used more efficiently to provide movement of freight and passengers. To date, the sector has experienced an increase in technological investments that are fundamental in driving efficiencies, better managed operations as well as offer passenger-focused-services (PFS) through industry 4.0 initiatives. Despite this wave of innovative technologies, the rail industry is struggling to bring them into full fruition due to a significant skills shortage. While various learning factories have been established both in industry and academia in the last decades, there is a need to interlink the activities within these various learning factories in order to address skill shortages. This paper aims at developing that link which will bridge the gap by establishing a state of the art learning factory (LF) concept that incorporates strategic initiatives such as customised training programmes and hands on experience to benefit graduates from various engineering disciplines in order to be ready for industry. Various concepts were developed and selected using decision matrix processes through the allocation of certain scores and ratings on each criterion as well as of synthesis of this rating using the standard procedures obtained through the application of Pugh Matrix, in order to select the most optimum LF design concept. In addition, a systematic layout planning (SLP) approach was used to analyse the sequence of operation performed within the proposed LF concept as well as understanding the relationship between the various workstations. The results reveal the chosen concept which the most suitable characteristics in LF design for the rail manufacturing industry. Lastly various projects were proposed in order to determine the performance of student group within the proposed LF concept.