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The design of manufacturing systems is a complex and expensive task for both SMEs and large organisations alike. Many problems relating to the design and operation of manufacturing systems are too complex to allow for mathematical treatment, and as a result there is increasing recognition of the applicability of simulation in the manufacturing environment. This has in turn resulted in a growth in simulation software products available in the marketplace, and manufacturers of such products are naturally keen to extol the virtues of what they sell. In a rapidly changing workplace, there is some suggestion that simulation tools may not have developed to deal with the new demands, and so it is timely to review what is on offer. This paper presents the results of a survey of European simulation specialists, both working in industry and in an academic environment, on the use of simulation software. The main purpose of this survey was to determine how satisfied users are with simulation software and to highlight the most positive and negative features. The findings offer an insight into current software, and how this can be further enhanced.

Typical assembly cell development requires that the hardware be mostly functional before significant software development can begin. Utilizing a software simulation of the hardware allows concurrent development of the hardware and software and provides many benefits including reduced time to market. Traditional simulation tools, though, are geared towards prototyping and early application development, but for advanced applications are of little or no use during later stages of development and deployment. The Cimetrix CODE (Cimetrix Open Development Environment) system provides a unique solution that supports development of a single software application that can drive not only the simulation, but also the physical machine, without the use of a translator. CODE applications run on Windows NT and can take full advantage of the wide range of third party software and hardware available on that platform. This article will explore the use of simulation throughout the life cycle of an assembly cell, including project definition, development and maintenance, and discuss the benefits that simulation can provide.

The purpose of this paper is to identify a business simulation appropriate for MEng Engineering students. The selection was based on the following factors; exploring methods for evaluating potential software and enhancing the learner experience.

An interdisciplinary project team was formed to try and resolve the pedagogic, technical and business aspects that would need to be addressed in order to implement such software within the programme. Tools included a questionnaire to assess the potential enhancement of employability skills and a usability questionnaire on ease of use. These were supplemented with discourse on technical and pedagogic issues.

After the initial scoping study, the findings indicated that two business simulation software packages had potential. These were “Marketplace – Venture Strategy” and “SimVenture”. Marketplace proved to be the most suitable in terms of the pedagogic and technical requirements.

The authors were not able to fully trial each simulation over the recommended duration of play because of practical time constraints and they did not have any student contribution to the process. Findings will need to be verified with the piloting cohort of students. Further pedagogic research could be carried out to evidence the enhancement to the student learning experience.

This study is valuable because it purposefully uses an interdisciplinary team comprising expertise in teaching and learning, technology, business and sector knowledge. This was vital in the decision‐making process. It is also valuable in its development of generic methods and tools to measure and evaluate software suitability in relation to usability and employability skills.

The aim of this paper is to highlight the application of six sigma, software engineering techniques and simulation to software development with a view to improving the software process and product.

This paper attempts to integrate six sigma and simulation to define, analyse, measure and predict various elements of software development (such as cost, schedule, defects) that influence software quality, thereby helping the software personnel take necessary measures early in the development process to improve the software processes and remove defects. Simulation results provide qualitative and quantitative suggestions on the ways to change the software process to achieve six sigma quality. The integration of six sigma and CMM and the role of knowledge management in software organisations have been taken into account.

Most software organisations operate between 2.3 and 3 sigma level. This paper presents a framework for definition, measurement, and analysis of important elements of the software product and process using six sigma tools and exploits the use of simulation in bringing six sigma improvements. Case studies have been presented to demonstrate the findings.

Application of the techniques presented in this paper would definitely improve software organisations' processes and product.

The adoption of methodologies outlined in this paper in software companies would enable them to attain improvements in terms of cost, schedule and quality.

The integration of simulation with six sigma applied to software development is novel in this paper. This paper will be valuable for quality professionals and management personnel in software organisations.

In order to be competitive and progress to a state of excellence in manufacture, companies are currently experiencing change. Decisions have to be made about the best way forward, and some insight into the possible outcomes is desirable. There is a small but growing awareness among British manufacturing companies that simulation could aid this insight, but potential users face the problem of evaluating and selecting from the many proprietary systems, the one which best matches their requirements at some preferred cost. Selection is made more difficult by continual updates and modifications to systems and by new software suppliers entering the market. Uses a research case study as the vehicle for proposing a framework for assessment and selection of simulation systems involving the use of the Analytic Hierarchy Process (AHP). Illustrates how this technique was used to make a system selection which matched a company′s selection criteria.

The purpose of this paper is to improve the understanding of the role of the bottlenecks in the dynamic software development supply chains. The paper examines the effects of the task priorities in the software development and investigates the possible strategies to manage them effectively.

In this paper, a software development supply chain has been simulated. This includes modeling of the various sizes of software requirement, different priorities, variations in development times, quality defects, etc. The model assumes a fixed set of resources of various skills. The model is studied for the bottlenecks, throughput, work in progress (WIP), etc. under various work preemption scenarios.

The results indicate that job priorities impact the bottleneck formulation, throughput and WIP of the software development. The work interruption policies to accommodate priority jobs adversely impact the throughput. Selective introduction of interruptions by leaving the bottlenecks from interruptions helps balancing the throughput and priorities.

The impact of the learning curve and knowledge acquisition time needed by the resources to restart the interrupted work has not been considered in this paper, which can be a future area of research.

The paper helps the practicing managers evaluate the dynamics of the bottlenecks with various task management approaches and comprehend the possible tradeoffs between priority and throughout.

The paper looks at software development from a perspective of workflow dynamics. This is a pioneer effort, as it utilizes simulation and modeling approach in understanding the software supply chains better.

The aim of this paper was to explore the use of objective fabric parameters in 3D virtual garment simulation.

Two methods (fabric assurance by simple testing and Browzwear's fabric testing kit) of obtaining objective fabric measurements and the derived parameters for virtual garment simulation were studied. Three parameters (extension, shear and bend) were investigated to establish whether the selected virtual software derived comparable parameters from the objective fabric measurements.

It was found that the conversion from the objective fabric measurement data to the required parameters for virtual simulation varied significantly. Manual analysis of the objective measurements showed the two test methods to be comparable for extension and shear parameters; However, some adjustment to the test method was required. The third parameter to be investigated (bending rigidity) concluded that the test methods and results obtained from the two different apparatus were not comparable and recommended further experimentation using a different testing technique.

Future research should be conducted on a larger variety of fabrics ensuring comparable loads are used in the testing of the extensibility parameters. An expansion of this preliminary study should give more conclusive evidence of the trends observed.

Objective measurement of extension, shear and bend properties was investigated in relation to the derived parameters for a selected virtual simulation package. An understanding of such parameters will aid the general industry in adapting 3D virtual garment simulation as part of the standard product development process, resulting in a significantly shorter product development cycle.

One of the most challenging problems facing industrial engineers concerns the design and operational planning of today′s sophisticated production systems. The need for a detailed quantitative analysis is far more apparent than ever before. The application of discrete‐event simulation has been growing rapidly in the analysis of production systems. This is because no other quantitative methods can provide the flexibility, realism and predictive accuracy offered by the simulation technique. Although the important role that simulation can play in analysing production systems has now been generally realised, its use is not necessarily straightforward. The successful implementation of simulation projects usually depends on several factors which include, inter alia, the availability of simulation expertise and the ability of the available simulation software to model readily and accurately the environment under consideration. The areas of production systems where simulation can be applied are outlined. The essential considerations which must be studied when applying simulation are also discussed. An overview of simulation modelling environments that are currently used is then taken. Recommendations for future work of importance from the system analysis viewpoint are highlighted.

Scheduling problems in steel plants tend to be difficult and require complex algorithms due to many constraints. An approach is presented where only the main constraints are included in the scheduling algorithm. The schedule is validated using a discrete‐event simulation model that includes additional detail.

The combined approach is utilised for production scheduling in a steel mill in Finland. Operational performance of the steel mill is measured before and after software installation. The paper presents the scheduling environment, the software application and the resulting increase of production.

Case experiences indicate that combining optimisation techniques with simulation is beneficial. The optimisation can be kept simpler as validation with a simulation model increases the credibility and accuracy of the resulting schedule. During software development and testing, the simulation model offered a testing environment for the optimisation algorithm.

The case implementation was a success that increased production without making trade‐offs with other production goals. Company management estimate the productivity increase directly caused by the project to be worth €2,500,000 annually.

The paper presents a successful application of simulation for schedule validation in a complex and demanding environment.

This study aims to report the development of a provisional robotic cell for additive manufacturing (AM) of metallic parts. To this end, the paper discusses cross-disciplinary concepts related to the development of the robotic cell and the associated command and control system such as the Computer-Aided Design (CAD) interface, the slicing software and the path planning for the robot manipulator toward printing the selected workpiece. This study also reports the development of a virtual production cell that simulates the AM toolpath generated for the desired workpiece, the adaptation of the simulation environments to enable AM and the development of a user application to setup, command and control the AM processes. If a digital twin setup is efficiently built, with a good correlation between the simulation environment and the real systems, developers may explore this functionality to significantly reduce the development cycle, which can be very long in AM applications where metallurgic properties, part distortion and other properties need to be monitored and controlled.

To generate the robot manipulator path, several simulation programs were considered, resulting in different solutions to program and control the robot of choice [in this study, Kuka and Asea Brown Boveri (ABB) robots were considered]. By integrating the solutions from Slic3r, Inventor, Kuka.Sim, Kuka.Officelite, RobotStudio and Visual Studio software packages, this study aims to develop a functional simulation system capable of producing a given workpiece. For this purpose, a graphical user interface (GUI) was designed to provide the user with a higher level of control over the entire process toward simplifying the programming and implementation events.

The presented solutions are compatible with the simulation environments of specific robot manufacturers, namely, ABB and Kuka, meaning that the authors aim to align the developments with most of the currently realized AM processing cells. In the long-term, the authors aim to build an AM system that implements a produce-from-CAD strategy i.e. that can be commanded directly from the CAD package used to design the part the authors are interested in.

This study attempts to shed light on the industrial AM, a field that is being constantly evolved. Arguably, one of the most important aspects of an AM system is path planning for the AM operation, which must be independent of the robotic system used. This study depicts a generic implementation that can be used with several robot control systems. The paper demonstrates the principle with ABB and Kuka robots, exploiting in detail simulation environments that can be used to create digital twins of the real AM systems. This is very important in actual industrial setups, as a good correlation between the digital twins (simulation environment and real system) will enable developers to explore the AM system in not only a more efficient manner, greatly reducing the development cycle but also as a way to fully develop new solutions without stopping the real setup. In this research, a systematic review of robot systems through simulation environments was presented, aiming to emulate the logic that is, used in the production cell development, disregarding the system brand. The adopted digital twin strategy enables the authors to fully simulate, both operationally and functionality, the real AM system. For this purpose, different solutions were explored using robots from two different manufacturers and related simulation environments, illustrating a generic solution that is not bound to a certain brand.

Using specific programming tools, fully functional virtual production cells were conceived that can receive the instructions for the movements of the robot, using a transmission control protocol/internet protocol. Conversion of the CAD information into the robot path instructions for the robot was the main research question in this study. With the different simulation systems, a program that translates the CAD data into an acceptable format brings the robot closer to the automatic path planning based on CAD data. Both ABB and Kuka systems can access the CAD data, converting it to the correct robot instructions that are executed. Eventually, a functional and intuitive GUI application capable of commanding the simulation for the execution of the AM was implemented. The user can set the desired object and run a completely automatic AM process through the designated GUI. Comparing ABB simulation with the Kuka system, an important distinction can be found, namely, in the exportation of the programs. As the Kuka program runs with add-ons, the solution will not be exported while maintaining its functionality, whereas the ABB program can be integrated with a real controller because it is completely integrated with modules of the virtual controller.

To conclude, with the solutions exploited, this study reports a step forward into the development of a fully functional generic AM cell. The final objective is to implement an AM system that is, independent of any robot manufacturer brand and uses a produce-from-CAD strategy (c.f. digital manufacturing). In other words, the authors presented a system that is fully automatic, can be explored from a CAD package and, consequently, can be used by any CAD designer, without specific knowledge of robotics, materials and AM systems.