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Belt grinding is commonly used in the finishing of non-functional shaped surfaces of surgical instruments. Most often it is carried out manually. The subject of this article is the possibility of replacing manual belt grinding with robotic grinding. A research stand was built, the machining process was programmed, and a comparative study of manual and robotic grinding was carried out. The subject of the research were the arms of orthodontic forceps. The condition of the treated surface, defined by its structure and roughness and the geometric accuracy and the error of the shape of the arm in the selected cross-section were adopted as the comparative criteria. Research has shown that robotic belt grinding is more efficient in terms of quality and produces more consistent results than manual grinding.

The article presents the possibility of compensating for the negative impact of filament humidity on the mechanical properties of parts produced by the FDM method by selecting appropriate process parameters, such as: layer thickness, deposition speed, deposition temperature and chamber temperature. The rules for selecting the process parameters were established on the basis of the results of the experiment, which allowed to identify the main and internal relations between the properties of the product and the process parameters, as well as the humidity of the filament. It was found, that layer thickness is the parameter of the FDM process which compensates for the negative impact of material moisture to the greatest extent.

The paper presents the methodology and implementation of original Automatic CAM programming using machining templates (ACPUT) dedicated to manufacturing special technological tooling. The development of ACPUT was inspired by the observation that although modern computer-aided design (CAD) / computer-aided manufacturing (CAM) systems can automatically create CAM programs, their universality makes them both difficult to use and inefficient because the programs created this way often contain errors. The presented programming procedure includes the development of specific machining templates based on technological knowledge gathered in a specially prepared database. These templates are dedicated to a group of parts characterized by the similarity of their geometric features. ACPUT makes it possible to reduce(in comparison to traditional CAM programming) the time required to develop a machining program, thereby positively impacting the total cost of tooling production. The paper aims to present results of testing the effectiveness of the use of ACPUT by technicians with different levels of experience (expert and beginner). The tests were carried out on special tooling - assembly equipment for plastic pipes, and compared program preparation time, machining time, and production costs.

The article presents the results of research on the influence of the natural moisture of a filament made of acrylonitrile–butadiene–styrene terpolymer (ABS) on the mechanical properties and quality of products fabricated with fused filament fabrication (FFF). The concept of the natural moisture of the filament was defined, and the range of its variability was identified in reference to the range of the natural ambient humidity. It is shown that a change in the ambient humidity by 10% resulted in a change in filament moisture by about 0.05%. The results of the research on the moisture variability of an ABS filament stored in a package, an airtight container, or a container with a moisture absorber are also discussed. The last part of the article presents the results of the research on the impact of the moisture of the filament in its natural range of variability on select mechanical properties of filaments and products made using FFT. It is shown that this impact was significant and had a value of 1 MPa on 0.1% filament moisture.

Design of Experiments is one of the tools for improvement and optimizing of products and manufacturing processes. Experiments conducted in industrial conditions should marginally interfere with the course of a studied process. The subject of the paper is the analysis of the impact of polyurethane foam-forming parameters on its strength properties, i.e., tensile strength and elongation at break. The tests were carried out on flexible foam molded for car seats. The measured parameters were: mixing pressure in the head, the volume of the mixing chamber, and time to prepare the pressure. The purpose of experiments was also to analyze the interactions of parameters on foam properties. A full factorial experiment was used for this. Eight combinations of parameters were developed, and on their basis, foams were prepared from which test samples were cut out. The foams were made using a one-step method. The results showed that both the elongation and strength have the greatest influence on the mixing pressure.

Purpose This paper aims to study strength properties and accuracy of a new type of composites, in which matrix is manufactured additively, whereas infill is a polyurethane resin. The process of manufacturing these composites is invented and patented by authors. Design/methodology/approach The authors developed a method of manufacturing composites, which was then used to build samples for tensile and bending tests (according to ISO 572 and ISO 178 standards), as well as measurements of accuracy. Findings It was found that the method of composite manufacturing designed by the authors allows obtaining both stronger and cheaper parts in comparison with the traditional acrylonitrile butadiene styrene FDM parts. Research limitations/implications The research was limited to static tests only, and no dynamic tests were performed on the manufactured samples. The accuracy analysis is only a basic one. Practical implications Developed method allows to shorten the FDM process with simultaneous decrease of costs (in professional processes) and increase of strength of obtained products. Originality/value Application of composite materials presented in the paper will significantly expand possibilities of using FDM method to manufacture functional, strong parts able to carry higher loads. Application of different combinations of thermoplastic matrix materials with different resin infills will allow to control properties of obtained composites. The solution is currently subject of a patent.

In paper influence of shift work preferences on quality control effectiveness is examined. Shift work indicated as one of key work organizational parameters that decrease visual control [Kujawińska, Vogt 2013]. Adjustment to work hours rotation in weekdays results in problems with regards to day and night activation cycle (day and night disturbances - sleep) as according to environmental interview also private, social disturbances and medical problems. In paper research results based on experiment performed in company manufacturing electronics for automotive industry. Shift work impact on visual inspections that placed sequentially in chosen technological process was examined. Single operator day and night cycle effectiveness was analyzed. Correlation strength between preferences indicated by operators to work on particular production shifts, and in particular days and real control effectiveness.

The aim of research was focused on analysis of tool displacements during milling of hardened steel, conducted with various overhangs. The measurements of displacements were carried out in feed and feed normal directions. Moreover, the measurements of forces, vibrations and surface roughness’ parameters were also conducted.

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.

A characteristic feature of the wood machining processes is a high level of data uncertainty from these processes. This uncertainty is due to the influence of material environment, but also of the measurement system. On the one hand, the quality of the data is affected by the inhomogeneity of raw wood material, the uniqueness of its structure, the randomness of its natural defects, wood deformation and because of nature of wood, which depends on the conditions/environmental parameters. Moreover, the uncertainty of the measured data results from the engineering problems associated with the inaccuracy of cutting process and method of measuring the geometrical characteristics of wood. The subject of authors research is production process of the floorboard surface layer (lamella). Due to the material loss in the process of equalization of cut off wood plies, there is a need to redesign (develop) methodology of the rules to select material allowances. One of the stages of research leading to that is to describe statistical models which explain the nature of the observed variability of chosen woodworking operations. One of the critical features in the production process of the floorboard surface layer is its thickness. The paper discusses the engineering problems associated with the measuring method of this feature. Based on the observations and research results, a new methodology for measuring the thickness of the lamella is proposed. The study proposes a method and organization of measurement performance—the number and layout (net) of measuring points (grid points) on the surface of the lamella, the choice of measuring instruments, and the size and frequency of sampling. The proposed approach allowed to increase the usefulness of measurement results. According to the new methodology, date were acquired. Based on this—for chosen woodworking operations: cutting, drying and grinding—the statistical models of lamella thickness variation were built. The article describes these three models. These models will be used to decide whether to redesign a model of tolerance and the methodology of the rules to select material allowances for each operation. The authors formulate conclusions and recommendations to improve the methodology of the lamella thickness measuring.

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 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.