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Proceedings of the 24th International Conference on Flexible Automation & Intelligent Manufacturing; FAIM 2014
No full textPaper presented at the Proceedings of the 24th International Conference on Flexible Automation & Intelligent Manufacturing, held May 20-23, 2014 in San Antonio, Texas, and organized by the Center for Advanced Manufacturing and Lean Systems, University of Texas at San Antonio; Includes bibliographical references; In this article, a novel force control system for soft contact with an object of unknown mechanical properties is proposed by using an ultrasonic sensor implemented in a 3 DOF manipulator robotic system. The emphasis is on the development of a control system to allow soft contact with an object of nonlinear elastic contact properties. In this work a Multi-input Fuzzy Rules Emulate Network (MiFREN) scheme controller with adaptation is developed to regulate the contact force. We propose the use of an ultrasonic sensor in conjunction with a signal conditioning for force based on a parallel-distributed-model as well as the Hertzian model, and considering the transmission and reflection of ultrasonic wave properties. The IF-THEN rules for the MiFREN control are defined taking into account the human knowledge of a physical system and a stability analysis is developed by the Lyapunov method. The experimental results demonstrate that the system is able to find a stable first contact force and moreover the proposed controller is capable of controlling the contact force for both regulation and tracking tasks
Proceedings of the 24th International Conference on Flexible Automation & Intelligent Manufacturing; FAIM 2014
No full textPaper presented at the Proceedings of the 24th International Conference on Flexible Automation & Intelligent Manufacturing, held May 20-23, 2014 in San Antonio, Texas, and organized by the Center for Advanced Manufacturing and Lean Systems, University of Texas at San Antonio; Includes bibliographical references; The main purpose of this research is to construct a generic model for successful implementation of Total Quality Management (TQM) in Oil sector, and to find out the effects of this model on the organizational sustainability development performance (OSDP) of Libyan oil and gas companies using the structured equation modeling (SEM) approach. To achieve this aim, the adopted research approach covers both quantitative and qualitative methods. Based on the literature search, eleven quality factors with 42 items were identified to develop a questionnaire in order to identify the quality factors that are seen by Libyan oil and gas companies to be critical to the success of TQM implementation. 42 out of 45 questionnaires were returned sufficiently completed with response rate 93.33%. Hypotheses were developed to evaluate the impact of TQM implementation on OSDP. The empirical analysis demonstrates several key findings: data analysis reveals that there is a significant positive effect of the TQM implementation on OSDP. The analysis indicated that 24 quality factors are found to be critical and absolutely essential for successful TQM implementation. Semi-structured interviews were also conducted to discover how these CQFs are experientially rated in specific organisational contexts. An in-depth case study analysis of two selected organisations provided understanding of the process of successful TQM implementation. The results generated a structure of the TQM implementation framework linked to OSDP based on the four major road map constructs (Top management commitment, employee involvement and participation, customer-driven processes, and continuous improvement culture). Libyan oil companies should consider TQM as an innovative tool for improving OSDP in today’s dynamic industry environment.The findings suggest the notion that the TQM critical success factors (CSFs) should be implemented holistically rather than on a piecemeal basis to get the full potential of the TQ
Proceedings of the 24th International Conference on Flexible Automation & Intelligent Manufacturing; FAIM 2014
No full textPaper presented at the Proceedings of the 24th International Conference on Flexible Automation & Intelligent Manufacturing, held May 20-23, 2014 in San Antonio, Texas, and organized by the Center for Advanced Manufacturing and Lean Systems, University of Texas at San Antonio; Includes bibliographical references; In recent years, the green manufacturing is gradually becoming an important force in the development of automobile manufacturing enterprises in China. How to implement green manufacturing engineering through the green innovation is a realistic problem of China's automobile parts manufacturers. In this paper, green innovation system of tyre manufacturers in China has been analyzed from manufacturers, market and government. Furthmore, the model of green innovation of tyre manufacturers based on system dynamics has been established. According to the research data obtained from Cooper Chengshan (Shandong) Tyre Company in China, the dynamic simulation has been performed. With the estimation, related policy implications and measures required to realize the sustainable development of tyre manufacturers in China have been also discussed. The author believes that the green innovation is beneficial to resource saving, energy saving and environmental friendly in automobile manufacturing enterprise
Proceedings of the 24th International Conference on Flexible Automation & Intelligent Manufacturing; FAIM 2014
No full textPaper presented at the Proceedings of the 24th International Conference on Flexible Automation & Intelligent Manufacturing, held May 20-23, 2014 in San Antonio, Texas, and organized by the Center for Advanced Manufacturing and Lean Systems, University of Texas at San Antonio; Includes bibliographical references; Barrier-free facilities are necessary for the sustainable development of the country. This paper studied the needs of the elder and the handicapped people in the barrier-free facilities. It found that the elder and handicapped people such as wheelchair users were hard to enter and leave the vehicle because of posture problems. Although barrier-free design was considered in some models of vehicle, however, it is not generally used. The feasible design of portable vehicle seat was studied through the survey and anthropometry measurement. The human factors engineering analysis was applied in the prototype design of movable ergonomic seat. The posture problems were considered when the elder or wheelchair users needed to enter or leave the vehicle. This advanced design can provide a car chair that is safer, more comfortable, and more convenience to meet the needs of elder and wheelchair users. The prototype of movable ergonomic seat was tested. This prototype can support the ingress process and egress process. It can move the seat up, and then rotate 90 degree anticlockwise. When the seat is pushed close to the door, the elder and wheelchair users can easily leave the vehicle. If the elder and wheelchair people needs to enter the vehicle, the movable seat will move up, rotate 90 degree anticlockwise, and move close the door first. The user can easily and comfortably sit on the seat. The movable seat can move back, and then rotate 90 degree clockwise. The final step is to move down. Therefore, the elder and wheelchair users do not need to rise up their hands, shoulders and legs, and they can easily enter and leave the vehicle. Since this design is portable, so it will be suitable to apply in different models of vehicle. Thus, more elder and wheelchair users can be benefited by this ergonomic desig
Proceedings of the 24th International Conference on Flexible Automation & Intelligent Manufacturing; FAIM 2014
No full textPaper presented at the Proceedings of the 24th International Conference on Flexible Automation & Intelligent Manufacturing, held May 20-23, 2014 in San Antonio, Texas, and organized by the Center for Advanced Manufacturing and Lean Systems, University of Texas at San Antonio; Includes bibliographical references; Lean manufacturing seeks consistent and complete elimination of waste in order to optimize resources. However, the elimination of such waste in most cases is done through of trial and error, which usually entails more costs for the company. Given this scenario, this paper describes the use of Value Stream Mapping (VSM) and Simulation to a family of products in a company that produces machined parts for the automotive sector. This family corresponds to five models of different cylinder heads that undergo similar processing steps and use similar equipment in their processes. In order to identify waste, initially the current state value stream map of the system that manufactures the family of cylinder heads was developed, and thereafter the future state map was built, seeking to reduce or eliminate waste and implement a lean value stream. The future state map was also modeled in a simulation software, in order to evaluate the proposed improvements in the future state and propose scenarios that enable adequate decision making by the managers of the company, such as the event of an increased demand. The use of simulation together with VSM contributed to provide the following additional advantages to using only VSM: (a) use of random data in the analysis of the results, (b) the possibility of modeling different scenarios without changing the physical arrangement of the production line. The results obtained by applying the methods to the cylinder head manufacturing were: reduced lead time, increase in utilization rates, improvement in visual management, and increased productivity. In addition, the production line started to operate with the amount of operators needed to satisfy the deman
Proceedings of the 24th International Conference on Flexible Automation & Intelligent Manufacturing; FAIM 2014
No full textPaper presented at the Proceedings of the 24th International Conference on Flexible Automation & Intelligent Manufacturing, held May 20-23, 2014 in San Antonio, Texas, and organized by the Center for Advanced Manufacturing and Lean Systems, University of Texas at San Antonio; Includes bibliographical references; The ability to detect the onset of welding instability is a very powerful tool in welding process monitoring and control. Toward this goal, this study investigates a gas metal arc welding (GMAW) process by analyzing online monitoring signals. Two separate data sets are obtained from the process, which correspond to (a) a stable process after improvement and (b) a relatively unstable process which exhibits spatter and poor weld bead geometry. Voltage, current, wire-feeding speed and line speed signals for both data sets are analyzed and features are extracted from the raw signals using different signal processing techniques. Specifically, phase diagrams, signal distributions, and fast Fourier transform (FFT) methodologies are implemented. The process parameters differ for the data corresponding to the stable and unstable processes rendering the two data sets incomparable. As such, an overlapping region of parameters is selected and this data is used to develop a multi-layer neural network model. The model uses the features extracted to distinguish between the two datasets under the similar input conditions. The trained model is then used to classify data as being from a stable process or an unstable proces
Proceedings of the 24th International Conference on Flexible Automation & Intelligent Manufacturing; FAIM 2014
No full textPaper presented at the Proceedings of the 24th International Conference on Flexible Automation & Intelligent Manufacturing, held May 20-23, 2014 in San Antonio, Texas, and organized by the Center for Advanced Manufacturing and Lean Systems, University of Texas at San Antonio; Includes bibliographical references; The research aims to improve information flow management, by offering more transparent information exchange methods, tools and technologies. While the main target is towards new kind of information and communication
technologies (ICT) and systems, the work starts by defining a set of Performance Indicators (PIs) and Sustainability Metrics that are needed in the factory floor and management levels. Today performance indicators and sustainability metrics are measured in various manners in manufacturing companies. Some of the metrics and indicators are suitable only for company level while others are more specific and visible in the factory floor. The paper will categorize the m
Proceedings of the 24th International Conference on Flexible Automation & Intelligent Manufacturing; FAIM 2014
No full textPaper presented at the Proceedings of the 24th International Conference on Flexible Automation & Intelligent Manufacturing, held May 20-23, 2014 in San Antonio, Texas, and organized by the Center for Advanced Manufacturing and Lean Systems, University of Texas at San Antonio; Includes bibliographical references; Generative manufacturing technologies are gaining more and more of importance as key enabling technologies in future manufacturing, especially when a flexible scalable manufacturing of small medium series of customized parts is required. The paper describes a new approach for design manufacturing of complex three dimensional components building on a combination of laminated objects manufacturing and e-printing technologies. The micro component is made up of stacks of functionalized layers of polymer films. The concept is currently developed further in the project SMARTLAM, funded by the European Commission. The manufacturing system is based on a modular approach which enables the manufacturing of different small size batches with different modules. Different modules can be combined by defined Hardware and software interfaces. Avoiding time consumable and difficult programming caused by manufacturing a new product a Function-Block Runtime (FORTE) executes generated control application platform-independently and coordinates component module functionalities. The control system will integrate all processes as well as the base platform with features far beyond ordinary PLC systems. One aspect is the use of process data out of the data acquisition system to simulate and optimize the processes. These results are incorporated into the main machine control system. Another aspect is the vision system for flexible quality control and closed-loop positioning control with visual serving. The paper shows the first example of manufacturing technologies and demonstrates the control system approach by the example of the control system for alignment of different stack
Proceedings of the 24th International Conference on Flexible Automation & Intelligent Manufacturing; FAIM 2014
No full textPaper presented at the Proceedings of the 24th International Conference on Flexible Automation & Intelligent Manufacturing, held May 20-23, 2014 in San Antonio, Texas, and organized by the Center for Advanced Manufacturing and Lean Systems, University of Texas at San Antonio; Includes bibliographical references; Crowdsourced design concepts are reported to be more creative than internal ideas and the cost of idea sourcing from the crowds is less expensive than from the conventional sources. However, the crowdsourced design has not been well utilized especially for complex engineering systems. One of the reasons is that the crowdsourced data, information, and knowledge are not well managed and evaluated to generate the expected quality and feasibility. The aim of this paper is to present an evaluation framework for crowdsourced design concept management and to couple ideas and solutions with the purposes or objectives of new product development, more efficiently. In the paper, features and characteristics of crowdsourcing new product development are discussed, and formal measures are proposed. An illustrative example is presented to describe how the evaluation framework can be used in crowdsourcing desig
Proceedings of the 24th International Conference on Flexible Automation & Intelligent Manufacturing; FAIM 2014
No full textPaper presented at the Proceedings of the 24th International Conference on Flexible Automation & Intelligent Manufacturing, held May 20-23, 2014 in San Antonio, Texas, and organized by the Center for Advanced Manufacturing and Lean Systems, University of Texas at San Antonio; Includes bibliographical references; Simulation-based optimisation often considers computationally expensive problems. Successfully optimising such large scale and complex problems within a practical timeframe is a challenging task. Optimisation techniques to fulfil this need to be developed. A technique to address this involves decomposing the considered problem into smaller subproblems. These subproblems are then optimised separately. In this paper, an efficient algorithm for simulation-based optimisation is proposed. The proposed algorithm extends the cooperative coevolutionary algorithm, which optimises subproblems separately. To optimise the subproblems, the proposed algorithm enables using a deterministic algorithm, next to stochastic genetic algorithms, getting the flexibility of using either type. It also includes a constructive heuristic that creates good initial feasible solutions to reduce the number of fitness calculations. The extension enables solving complex, computationally expensive problems efficiently. The proposed algorithm has been applied on automated sheet metal press lines from the automotive industry. This is a highly complex optimisation problem due to its non-linearity and high dimensionality. The optimisation problem is to find control parameters that maximises the line's production rate. These control parameters determine velocities, time constants, and cam values for critical interactions between components. A simulation model is used for the fitness calculation during the optimisation. The results show that the proposed algorithm manages to solve the press line optimisation problem efficiently. This is a step forward in press line optimisation since this is to the authors’ knowledge the first time a press line has been optimised efficiently in this wa