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Reports on a new methodology for formation of virtual (“extended”) machining cells using generic capability patterns termed “resource elements”. Resource elements are used to uniquely describe the processing requirements of the component mix and dynamically match them to the processing capabilities of the machining shop. The virtual cell formation methodology is based on four steps: component requirement analysis and generation of processing alternatives; definition of virtual cell capability boundaries; machine tool selection; and system evaluation. The proposed methodology facilitates the dynamic formation of virtual manufacturing structures by providing accurate assessment of the component processing requirements and their matching with the available capabilities of the existing manufacturing facilities.

Hot‐cells are shielded structures protecting individuals from radioactive materials. The purpose of this paper is to propose a design approach for a hot‐cell simulator using digital mock‐up (DMU) technology and combining Haptic guided complex robotic manipulation for assembly tasks in a virtual environment.

The principal reason for developing a simulator was to explore the feasibility of hot‐cell structure design and collision‐free assembly process. For this, a simulation design philosophy has been proposed that includes DMU facility offering the ability of analyzing the operations and performing complex robotic manipulations in the virtual hot‐cell environment. Furthermore, enhanced Haptic mapping for tele‐manipulation is proposed for training and guidance purposes.

From the analysis and task scenarios performed in virtual simulator, the optimal positions of the manipulators and need of (bridge transport dual arm servo‐manipulators) type were identified. Operation tasks were performed remotely using virtual hot‐cell technology by simulating the scenarios in the DMU reducing the overall operation cost and user training. The graphic simulator substantially reduced the cost of the process and maintenance procedure as well as the process equipment by providing a pre‐analysis of whole scenario for real manipulation.

This research tries to contribute to the virtual hot‐cell design philosophy. Tele‐operated complex robotic operations in DMU technology are performed in virtual hot‐cell. The simulator provides improved Haptic guidance with force and torque feedback enhancing the realism of virtual environment.

The purpose of this paper is to develop an efficient and effective preventive maintenance (PM) plan that considers machines’ maintenance needs in addition to their reliability factor.

Similarity coefficient method in group technology (GT) philosophy is used. Machines’ reliability factor is considered to develop virtual machine cells based on their need for maintenance according to the type of failures they encounter.

Using similarity coefficient method in GT philosophy for PM planning results in grouping machines based on their common failures and maintenance needs. Using machines' reliability factor makes the plan more efficient since machines will be maintained at the same time intervals and when their maintenance is due. This helps to schedule a standard and efficient maintenance process where maintenance material, tools and labor are scheduled accordingly.

The proposed procedure will assist maintenance managers in developing an efficient and effective PM plans. These maintenance plans provide better inventory management for the maintenance materials and tools needed using the developed virtual machine cells.

This paper presents a new procedure to implement PM using the similarity coefficient method in GT. A new similarity coefficient equation that considers machines reliability is developed. Also a clustering algorithm that calculates the similarity between machine groups and form virtual machine cells is developed. A numerical example adopted from the literature is solved to demonstrate the proposed heuristic method.

This study isolates the effect of immersion on players’ learning in a virtual reality (VR)-based game about cellular biology by comparing two versions of the game with the same level of interactivityand different levels of immersion. The authors identify immersion and additional interactivity as two key affordances of VR as a learning tool. A number of research studies compare VR with two-dimensional or minimally interactive media; this study focuses on the effect of immersion as a result of the head mounted display (HMD).

In the game, players diagnose a cell by exploring a virtual cell and search for clues that indicate one of five possible types of cystic fibrosis. Fifty-one adults completed all aspects of the study. Players took pre and post assessments and drew pictures of cells and translation before and after the game. Players were randomly assigned to play the game with the HMD (stereoscopic view) or without the headset (non-stereoscopic view). Players were interviewed about their drawings and experiences at the end of the session.

Players in both groups improved in their knowledge of the cell environment and the process of translation. Players who experienced the immersive stereoscopic view had a more positive learning effect in the content assessment, and stronger improvement in their mental models of the process of translation between pre- and post-drawings compared to players who played the two-dimensional game.

This study suggests that immersion alone has a positive effect on conceptual understanding, especially in helping learners understand spatial environments and processes. These findings set the stage for a new wave of research on learning in immersive environments; research that moves beyond determining whether immersive media correlate with more learning, toward a focus on the types of learning outcomes that are best supported by immersive media.

The concept of virtual cellular manufacturing systems (VCMS) is finding acceptance among researchers and practitioners as an extension to group technology. This paper is related to a research work which resulted in designing and developing VCMS, which by virtue of its abilities proves to be attractive to manufacturing organisations fitting into the category of SMEs. VCMS consists of enterprise modeller (EM), cell design manager (CDM), cell operation manager (COM), simulator (SIM), performance evaluator (PE) and report generator (REP). The “cell design manager” is a very important constituent of the VCMS, as this module helps to generate a number of cell configurations using different algorithms. A new algorithm styled as “Better alternative to ROC (BETROC)”, which possesses many distinct features to generate a number of alternative solutions, has been developed and reported in this paper.

The aim of this paper is to illustrate a solution that can be used to reduce the severity of breakdowns and improve performances in the cellular manufacturing (CM) system with unreliable machines.

The performance of CM system is conditioned by disruptive events, such as the failure of machines, which randomly occurs and penalizes the performance of the cells, seriously disturbing the smooth working of the factory. To overcome the problem caused by the breakdowns, the authors develop a solution, based on the principle of virtual cell and the notion of intercellular transfer that can improve the availability of the system. In this context, the use an analytical method based on Markov chains to model the availability of the cell. The results are validated using simulation.

The proposed solution in this paper confirmed that it is possible to reduce the severity of breakdowns in the CM system and improve the availability of the cells through an intercellular transfer created at the time of a breakdown. Simulation allowed a validation of the analytical model and showed the contribution of the suggested solution.

The developed approach studies the performance of the production cells formed by unreliable machines. It uses the notion of the intercellular transfer to improve the availability of the cells.

Additive manufacturing (AM) technologies have recently turned into a mainstream production method in many industries. The adoption of new manufacturing scenarios led to the necessity of cross-disciplinary developments by combining several fields such as materials, robotics and computer programming. This paper aims to describe an innovative solution for implementing robotic simulation for AM experiments using a robot cell, which is controlled through a system control application (SCA).

For this purpose, the emulation of the AM tasks was executed by creating a robot working station in RoboDK software, which is responsible for the automatic administration of additive tasks. This is done by interpreting gcode from the Slic3r software environment. Posteriorly, all the SCA and relevant graphical user interface (GUI) were developed in Python to control the AM tasks from the RoboDK software environment. As an extra feature, Slic3r was embedded in the SCA to enable the generation of gcode automatically, without using the original user interface of the software. To sum up, this paper adds a new insight in the field of AM as it demonstrates the possibility of simulating and controlling AM tasks into a robot station.

The purpose of this paper is to contribute to the AM field by introducing and implementing an SCA capable of executing/simulating robotic AM tasks. It also shows how an advanced user can integrate advanced simulation technologies with a real AM system, creating in this way a powerful system for R&D and operational manufacturing tasks. As demonstrated, the creation of the AM environment was only possible by using the RoboDk software that allows the creation of a robot working station and its main operations.

Although the AM simulation was satisfactory, it was necessary to develop an SCA capable of controlling the whole simulation through simple commands instructed by users. As described in this work, the development of SCA was entirely implemented in Python by using official libraries. The solution was presented in the form of an application capable of controlling the AM operation through a server/client socket connection. In summary, a system architecture that is capable of controlling an AM simulation was presented. Moreover, implementation of commands in a simple GUI was shown as a step forward in implementation of modern AM process controls.

The purpose of this paper is to investigate the impact on the cost of materials used to conduct preventive maintenance (PM). The main motivation for this work is to demonstrate how the group technology concept can be used to improve PM operations. In assessing improvement, the impact on the cost of materials used to conduct PM is investigated.

Based on the similarities between machines required maintenance and failure types, machines are grouped together into virtual cells using similarity coefficients. These cells, then, are used to come up with more efficient planning and scheduling procedures to conduct PM operations including inventory of parts and the execution of maintenance operations.

The results demonstrated that the proposed PM approach could provide a significant cost savings over a traditional PM program, especially in industries for which there is considerable material cost for the performance of PM.

The results presented in this paper are reliable, objective, and may be expanded by using the same concept of developing virtual cells to group other types manufacturing operations.

The purpose of this research paper is to discuss cellular manufacturing is discussed under conditions of changing product demand. Traditional cell formation procedures ignore any changes in demand over time from product redesign and other factors. However given that in today's business environment, product life cycles are short, a framework is proposed that creates a multi‐period cellular layout plan including cell redesign where appropriate.

The framework is illustrated using a two‐stage procedure based on the generalized machine assignment problem and dynamic programming. This framework is conceptually compared to virtual cell manufacturing, which is useful when there is uncertainty in demand rather than anticipated changes in demand. A case study is used to explain how the concept would work in practice.

One major characteristic of the proposed method is that it is flexible enough to incorporate existing cell formation procedures. It is shown through an example problem that the proposed two‐stage method is better than undergoing ad hoc layout changes or ignoring the demand changes when shifting or cell rearrangement costs exist. It also sheds some insight into cellular manufacturing under dynamic conditions.

This paper should be useful to both researchers and practitioners who deal with demand changes in cellular manufacturing.

Proposes a virtual cellular manufacturing approach to implementing cellular manufacturing systems that combines the set‐up efficiency typically obtained by traditional cellular manufacturing or group technology systems with the flexibility of a job shop. Unlike traditional cellular systems in which the shop is physically designed as a series of cells, cells are formed within a shop utilizing a process layout using scheduling mechanisms. The result is the formation of cells that are temporary and logical (virtual) in nature, allowing them to be more responsive to changes in demand patterns. Simulation runs comparing this approach to production using traditional cellular and job shop approaches indicate that this new approach yields significantly better shop performance over a range of operating conditions.