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The article presents an extensive analysis of the literature on defining production leveling and the methodology for its implementation. The main aim of this article is to show how to change these factors after the implementation of production leveling. The article also presents an example of the implementation of leveling production at the department for the production of surgical instruments at a manufacturing enterprise. The current production scheme, including maps of material flow analysis, orders, and the flow from production are described. Finally, the article presents the successive steps in implementing the production leveling in the enterprise.

Information attributes for evaluating quality of process information have been established.A methodology of evaluating quality of process information is proposed.When designing the process documents, the information requirements of the process executor need to be taken into consideration.There exists a relation between attributes of process information and the type of process realized. Information is the main constituent of documents that make up a quality management system. The main function of information found in process documents is to provide knowledge regarding how to executing a process and to standardize this process by providing a specific path of execution. However, it is not easy to determine a standard level of quality of process information optimal from the viewpoint of the owner and the process executor. Since there is no universal standard that would allow evaluation of the quality of process information, the purpose of the presented studies was to solve the aforementioned problems and to provide practical solutions for document makers to design proper process descriptions. To achieve the main purpose, a methodology for examination of influence characteristics of processes on information requirements of users of process documents was created. The paper presents findings carried out in processes at enterprises and is aimed at finding relation between attributes describing information and characteristics of processes. The paper proposes a set of guidelines developed by the authors for selection of appropriate document characteristics. These guidelines are based on findings collected from the conducted research.

The paper introduces a concept of assessment of a ductile iron casting process with use of the rule-based approach, known as DRSA (dominance-based rough set approach). The research was conducted in a large Polish foundry. The collected data concern the chemical composition and mechanical properties of the used ductile cast iron. In the paper, a methodology of creating a rule-based moulding model for the tensile strength was proposed. The quality, sensitivity and accuracy of the model extracted from the data were examined. The studies proved its usefulness in the industrial practice and for aiding of the decision making process.

The article presents original computer software designed to assist in data acquisition and analysis for the purpose of value stream mapping for one of tools of lean manufacturing concept. The AnaPro program uses the collected data about manufacturing processes to analyse product demand, material supplies or manufacturing processes, which is then used as a basis for creating current state maps. Furthermore, the program allows for preparing variants of future state maps through an analysis of turnover classification, product demand and methods of production flow control. The article describes functions of AnaPro with regard to value stream mapping and a practical example of the software application is provided.

The paper presents new procedure of methodology for statistical assessment of measurement systems variation (methodology known in the literature as Measurement Systems Analysis, MSA). This procedure allows for calculation and monitoring in real time (that is on-line) of measurement system (MS) characteristics which determine its usability for manufacturing process control. The presented solution pointed out the gap in process control, which consists in lack of methods for monitoring measurement processes in the on-line way. Their key point consists of taking samples that are also needed for the process control chart for the needs of the MSA method. This means that the samples are taken directly from the production line and during the production process. The method is combined with the standard procedure of statistical process control (SPC) with the use of process control charts. It is based on two control charts. The first one is called AD-chart (Average Difference chart) and it allows to estimate the variation between the operators and stability of the monitored measurement system. The second control chart illustrates the %R&R index (Repeatability and Reproducibility) and allows to monitor the MS capability.The paper also presents authors’ proposal of guidelines about the reference value for the %R&R index calculation and assessment. Recommendations and guidelines for choosing the reference value are based on two criteria: information about sample and manufacturing process variation and the purpose of using MS (product or process control).

The paper presents a process of adaptation of the Oculus Rift and Samsung Gear VR devices for needs of immersive training application. The process was described on the example of virtual 3D human body atlas, created using EON Studio software. The aim of this application is to facilitate and make it more attractive to learn anatomy for students of medical disciplines. Possibilities of the application are, among others: selection of visibility level of certain organs or groups of organs, creation of complex sections in 3 planes and launching animations of selected organs. Application of each selected device required additional programming work. The work included both adaptation of Graphical User Interface for different display resolutions, as well as preparation of communication between integrated orientation tracking systems and the application, because none of the selected low-cost HMDs has a position tracking system, to allow navigation in the virtual space, two low-cost solutions were proposed, as well as traditional approach in form of a professional tracking system. First of the proposed low-cost solutions is application of a dedicated, customized controller built in the PUT VR Laboratory using commercial electronics and 3D printing technologies. The second solution is controlling the navigation via specific gestures recognized by the Kinect low-cost tracking device. After application was developed, a group of students tested all possibilities of interaction with the virtual environment using a professional HMD and both low-cost display and tracking solutions. During the evaluation performed by the test group, features like field of view, weight of devices and general impressions and feeling after prolonged use were taken into consideration. Intuitiveness of the proposed navigation solutions was evaluated separately. The evaluation performed by the test group can be used during work on subsequent versions of the medical educational application and design of new peripheral devices.

The paper presents a Virtual Reality system developed as a result of cooperation of the University and an industrial company – a major city bus manufacturer. Main objective of work presented in the paper was to obtain a tool suitable for daily work with the clients on configuration of visual features of customized city buses. A city bus can have more than 100 visible features (options), which can be changed to obtain virtually infinite configuration possibilities. Visual representation of many of these features was largely unavailable before the presented work was commenced, resulting in certain problems in process of communication between salesmen and clients. The developed Virtual Reality system allows for visual representation of the bus functions during the configuration process, so it solves many problems in the client-company communication. It is also a knowledge base of all visual options which can be changed in scope of the configuration process – knowledge from many departments of the company was used to develop it, including knowledge unknown to representatives of sales and marketing. As a result, the immersive configurator can be effectively used to train salesmen and marketing representatives in terms of technical knowledge about customization capabilities of the offered product. The paper presents shortly the overview and functions of the whole system. The system is a large, multi-modal solution built of many software and hardware components and is also integrated with other, existing systems. It allows to display high-quality images of a configured bus in real-time in stereoscopic 3D on a large screen, as well as using professional Head-Mounted Display or low-cost systems (e.g. Oculus Rift) for a virtual walk inside the configured bus, with full integration between all the visualization instances. Interaction with the system is divided into several groups of functions – configuration, navigation, animation and extra functions. Different devices are used for interaction: joystick, gyroscopic mouse and gesture recognition systems like Kinect can be used for navigation and animation, while most of the configuration and extra functions are launched using a graphical user interface, operated using a touch screen or a tablet. Efficiency of the system in the visual configuration process was confirmed by representatives of the company. Capabilities of the system for education was tested using a sample of non-technical users from the sales and marketing department, using the system and then leaving their impressions in a survey study. It confirmed high effectiveness of the system in terms of presenting variability of the product features in a clear visual way. Immersive aspect of the system was also valued very high – usage of the stereoscopic 3D and Head-Mounted Device allowed to present the bus in a more realistic way than it was possible earlier. In the near future, the system will be fully developed and implemented to use in the sales process.

The article describes a new, original approach to integrated ecodesign of products and technological processes, ensuring appropriate selection of materials and connections from the point of view of recyclability. The method was implemented in an expert system. The decision tree induction method was used as the system tool. The expert system offers a practical solution which makes it possible to change a material or connection without having to consult the product designer. It is consistent with concurrent engineering (CE) design.

The paper demonstrates that the effective replacement of conventional machine tools with numerically controlled machinery (CNC) requires the simultaneous conducting of actions related to organization and control of production, management of human resources, and tool economy. The direct costs of machining for a selected group of surgical tools, performed with the use of conventional, as well as CNC machinery, were analyzed. The assumptions adopted for the analysis of profitability of machinery park restructuring were compared with the actual costs generated after a year from implementing the project.

The paper discusses usability of various pattern recognition methods, especially based on artificial neural networks for decision making support in process control chart analysis. Their effectiveness for detecting process instability is compared with the effectiveness of a human operator and of a widely accessed commercial statistical software. The results are verified on the basis of data obtained from real production processes.

The paper presents a decision support system for quality tools and techniques (QT&T) selection and application. While solving problems and improving enterprise processes and products, there is often a significant problem connected with fast, easy and flexible choice of appropriate tools for solution activities. The premise of the system elaboration was richness and variety of quality tools – ranging from technological solutions (e.g. statistical process control (SPC)) to organisational and behavioural techniques (e.g. nominal groups technique (NGT)), as well as the lack of applications, making fast and apt selection of QT&T, especially in the production conditions. The system includes knowledge about management tools and techniques and, in contrast to traditional handbooks, is written in structured form. It should be stressed that this knowledge not only describes the possibilities of tool usage (theoretical view), but also points out the constraints in their practical implication (knowledge captured from...

Quality inspection is very often one of the most important stages of the production process, although it does not create any added value. Therefore, optimization of the related number of activities is of crucial importance. However, reduction should not be made arbitrarily, but preceded and documented by appropriate research. The article describes a study aimed at reducing the high cost of quality inspection as part of the manufacturing process of a diagnostic catheter at a medical company. The product is used for blood pressure monitoring and blood sampling by the Seldinger technique. A critical quality feature for the catheter is air/water tightness. Following a thorough analysis, some control points were eliminated, and others were improved. The resulting conclusion is that detection of defective components is the most beneficial for this specific production process if carried out during the 100 percent final quality inspection. The finding is based on the fact that the cost of producing the final device with a defective component is lower than a quality inspection run directly after each operation. The authors also managed to decrease the sample size for control charts used to supervise the adhesive connection strength.

The paper presents selection process of an appropriate engine to build a dedicated visual configuration system based on Virtual Reality, in cooperation with a city bus producer. The aim was to build a methodology of selection of such a software for a large visual configuration system and to validate it in practice, as there are no available software benchmarks in VR branch. To aid the decision making process, the Analytical Hierarchy Process method was proposed. Several most popular engines were taken into account. Final solution using the selected engine is also presented in the paper as a practical validation example.

Implementing the smart factory concept places demands not only for enterprises but also for scientific units. In order to be able to effectively develop solutions in compliance with the Industry 4.0 concept, it is necessary to improve qualifications of scientific personnel and students who are supposed to implement those assumptions in practice. The paper describes the structure of smart factory model, developed at Poznan University of Technology, which enables both learning about such solutions and doing research work in that scope. The model includes issues connected with the field of production management – starting from interpretation of client requirements, to automation of product design development, to preparing and controlling the production process.

This paper presents a process of building a prototype of an educational application for teaching anatomy with elements of physiology, with use of a Virtual Reality environment. Preparation of mesh models of individual human organs is described, along with further visualization techniques, which were used to ensure a proper level of a visual representation. Stages of user interface preparation are also described – both visual and functional aspects covered – with a detailed review of a visual programming process, which was used to obtain a logical structure of connections inside the VR environment. Process of preparation of dynamic graphical data-namely animation of the pulmonary alveoli – and integration it with the virtual environment is also presented. The final application can be used in a number of ways, including large-screen stereoscopic projection with on- screen graphical user interface and single-user immersive stereoscopic projection using a head-mounted device with an optical tracking system. Results of assessment of the application advantages and disadvantages at the current stage of development allowed to formulate several directions of further advancement.

Effective medical and biomedical engineering education is an important problem. Traditional methods are difficult and costly. That is why Virtual Reality is often used for that purpose. Educational medical VR is a well-developed IT field, with many available hardware and software solutions. Current solutions are prepared without methodological approach. As a result, each VR system used for medical purposes is unique - there is no standardization, which leads to increased development time and costs. The paper presents an original methodology that can be used for building immersive virtual reality (VR) applications dedicated to training medical skills. The methodology is named “knowledge-oriented medical virtual reality” (KOMVR), as it uses basic knowledge-engineering tools during processes of planning, building and verification of interactive educational solutions. The paper shows successive stages of the methodology and the tools used for its execution. Effectiveness of the proposed methodology is illustrated with a simple example – a human body atlas. Major time reduction can be achieved while using the methodology - time reduction in the presented case was from 50 to 14 working days. The proposed innovative approach can increase effectiveness of preparation of educational VR solutions in medicine, but also in other branches of engineering.

Virtual reality (VR) may be used as an innovative educational tool. However, in order to fully exploit its potential, it is essential to achieve the effect of immersion. To more completely submerge the user in a virtual environment, it is necessary to ensure that the user’s actions are directly translated into the image generated by the application, which can be achieved by means of various devices, such as tracking systems and VR headsets, as well as haptic devices. Recently, VR has become the focus of e-entertainment, which has resulted in the appearance on the market of numerous, low-cost peripheral devices. The paper discusses the examples of potential applications and steps necessary to adapt low-cost devices to immersive educational applications.

Quality was always of utmost importance in Poland, irrespective of historical, political, and economic circumstances. But quality understanding and quality assurance have changed in Poland over time, both from the customer's and producer's points of view. It is a result, to a large extent, of the very turbulent and dramatic turns in Polish history. The purpose of this publication is to show changes in the approach to quality management in Poland in the past 60 years. These changes are considered in the context of improvement and pursuit of excellence in enterprise management. This paper consists of five parts. The first part presents the author's understanding of improvement and excellence. Parts two and three convey general knowledge and characteristics of quality management in Polish companies in two periods: before 1990 and in the past 20 years. The year 1990 was chosen as the turning point because it was then that the Polish economy irrevocably changed from a centrally planned economy to a market-orie...

This article presents the investigation of selected work environment factors with regard to the quality of manual assembly process. It describes the research carried out in a natural work environment and conditions in a factory producing car wire harnesses. It has been pointed out that only a few work condition factors have a significant influence on the assembly process's quality. The results of the experiments have proved the hypothesis that, between the two important work factors (noise level and work monotony), there is a significant interaction with respect to their impact on the assembly quality process. © 2010 Wiley Periodicals, Inc. © 2011 Wiley Periodicals, Inc.

The paper presents studies on design and implementation of a complex Virtual Reality system for product design. Main objective of work presented in the paper was to obtain a tool suitable for on-line work with the clients on configuration of visual features of customized city buses. A complex product such as a city bus can have more than 100 visible features (options), which can be changed to obtain infinite configuration possibilities. The paper presents the overview and functions, as well as development process of the created system. Efficiency of the system in the visual configuration process was confirmed by representatives of the company. Capabilities of the system were tested using a sample of users from all the company departments involved in the bus design process. It confirmed high effectiveness of the system in terms of presenting variability of the product features in a clear visual way and improvement of the whole configuration process.

The new requirements for products quality and manufacturing process productivity can not be met by using traditional methods. This paper presents a new approach to improving the efficiency of quality control in machining. The method is especially suitable for quality control with the use of Shewhart's control charts (SCC). It is based on processing signals that accompany machining processes (e.g. acoustic emission, force, vibrations) with the use of fuzzy reasoning and neural network. The on-line measured signals are transformed through the process safety function (PSF) which is developed on the basis of two quantities specially defined for this method: the process quality of performance (QOP) and the process state vector (PSV). It is finally used for estimation of the process safety index (PSI). Inference models developed in this work can easily be identified and modified under workshop circumstances.

The paper presents two methods that support quality-oriented process control which are based on elements of intelligent data processing like self-learning and fuzzy inference. They provide additional information about process safety and enable the human to operate the process with more comfort and safety. They allows also to optimise the efficiency of statistical process control.

The paper presents problems related to measurement accuracy of tracking systems, which are widely used in immersive simulations based on Virtual Reality technology. Possibility of tracking movements of the user makes the simulation in virtual environment more realistic. This is very important in case of training simulations of situations, where mistake of an operator would threaten the life and health of himself or other people or could lead to substantial material losses. The authors’ many years of experience in creating interactive Virtual Reality applications allows them to conclude, that possibility of use of professional tracking systems is often not possible for educational facilities like schools or universities due to budget reasons. Professional tracking systems are usually more accurate and have more programming support of their use in Virtual Reality applications than the low-cost solutions. However, low-cost devices are often tens of times cheaper than the professional systems. The research presented in the paper is an attempt of answering the question – how the immersion level related to accuracy of position and orientation representation of real object in a virtual environment influences the evaluation of usefulness of a given tracking system for training applications. A particular attention was paid to tracking of user's movement, which allows him to naturally interact with the computer generated environment. Displaying a simulation reacting properly and smoothly to real movements performed by the user will allow him to develop the most necessary reflexes, which would not be possible using only non-natural interaction devices, such as mouse or keyboard. On the other hand, development of improper reflexes related to user's position being wrongly read can bring more harm than benefit to the training process. The paper presents results of study of accuracy of one of the tracking systems available on the market – the PST 55 system. This device uses retro-active markers, which are widely used also in measurement systems not dedicated to use in the VR system. The real position of tracked objects was verified using an industrial photogrammetric measurement system TRITOP from GOM company. The results of the comparative study allowed to determine how accurate is the studied tracking system and how the accuracy affects the feeling of immersion.

The authors introduce the problem of excessive waste of raw material in the wood industry on the basis of the floorboard manufacturing process. The study was aimed to optimize the process of lamella grinding – the final stage in the manufacturing of the oak surface layer. The paper describes implementation of the design of experiments (DoE) methodology to improve the production process of the floorboard surface layer (lamella). The authors made certain assumptions and designed an experiment to obtain high quality lamellas and minimize the waste of raw material. A three -factor full factorial experiment was conducted. The paper presents the conducted study and the authors’ recommendations concerning the determination of optimal machining parameters (on the basis of the results of Experiment 1), parallel arrangement of lamellas (on the basis of Experiment 2), and minimum machining allowance (Experiment 3).