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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 subject of the study are short sandwich beams with special structure of the core (honeycomb). The beam is made using additive manufacturing technology. The values of elastic modules vary along beam. The linear shear deformation theory – the “zig-zag” hypothesis is assumed for plane cross section. The analytical model of beam is based on this hypothesis. The deflection of beam is analytically calculated. Moreover, the deflection of beam is experimentally determined on a test stand. The results of these two methods are compared.

The Virtual Reality technology is nowadays dynamically developed, thanks to appearance of low-cost devices and interest by large companies related to entertainment, communication and visualization. It is especially important in medicine, as it allows a much wider access to tools such as Virtual Reality Exposure Therapy. The paper presents possibilities of using low-cost VR devices in curing phobias by exposure to a stress-generating factor in an immersive virtual environment. Several use scenarios are presented for a simple application aimed at exposing a patient to fear of heights. A test group consisted of healthy individuals. To evaluate level of immersion and fear caused by the application, a heart rate monitor was used, to record heartbeat in real time.

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.

Nowadays future designers are required to explore different fields of engineering (e.g. basis of design and operation of machines, methodology of process design, characteristics of phases of a product life cycle, ergonomics, etc.) in order to obtain sufficient knowledge about the product, the problems of its operation and related services. Currently, there is a strong tendency to take into account the impact of a product on the natural environment. The handling of products that are withdrawn from usage is one of the big problems emerging in a modern society. One of the possibilities to solve these problems is taking into account the environmental issues at the very early stage of the product design. Authors created the methodology to include recycling requirements in the phase of design of the product with support of the CAD 3D systems14,15. In details, the method of ecological-oriented product assessment during the design process was implemented in CAD 3D environment in order to improve the skills and knowledge of future designers about environmental aspects of the designed product12. In order to enhance the effectiveness of the training of designers, authors decided to use immersive Virtual Reality (VR) technologies that are more and more often used as advanced training systems. The user/trained person can explore Virtual Environment (VE) for educational and exercise purposes5. Immersive VR technologies are gaining wider use as engineering design tools to support the product design phase because of their ability to deliver an immersive and user friendly environment that can be used as digital test-bed for prototypes of the product30. Paper briefly describes the analysis of the recycling of selected product designed in the CAD 3D system with the support of Virtual Reality technologies that were based on the recycling product model (RpM) and the agent technology12,14,15. The RpM, developed during the geometric modelling phase, includes the data necessary for a comprehensive product recyclability evaluation already at the design stage. This approach allows designer to select appropriate solutions that facilitate future disassembly and to choose materials most suitable in terms of future recycling. The analysis allows to make an assessment of the susceptibility of the product for recycling using the agent system. The agent system, in accordance with the recycling product model (RpM) that was implemented in the 3D CAD system, is an innovative tool for the designer to enable a comprehensive assessment of the product in terms of its susceptibility to recycling. Future designers (students of mechanical engineering fields) gained possibility to improve their skills and knowledge in the field of ecodesign through the immersive trainings of virtual product design for recycling. Applying the Virtual Reality technologies for training of the future designers was aimed at enhancing the effectiveness of training mainly due to immersion and interaction with the virtual environment and to explore the product before it is constructed, as well as provide learning of the environments in which the finished product will be operated. As the example of the recycling-oriented virtual product design, case study of the design of small household appliance is presented. Participants of the immersive training (students) have a possibility to design the product in the Virtual Reality and select the optimal variant, which meets all environmental requirements. Short description of the recycling modeling (creation of connections, defining the extended materials and disassembly attributes) as well as an example of recycling assessment such as calculation of recycling assessment measures or providing tips and suggestions generated by agent system is also presented.

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.

In the Poznan University of Technology Chair of Production Engineering and Management, a Virtual Reality –Rapid Prototyping team has been active for many years and one of the studied activities is possibility of VR use in classes for higher education. As a result of cooperation with one of the medical universities in the region, an educational application has been developed, as a didactic aid during anatomy, physiology and pathology courses. During the test use, the application has been found quite interesting for both the lecturers and the students. It allowed, among other things, to freely slice the virtual human body and showing and hiding selected groups of organs, in order to allow detailed inspection of human anatomy by the user. This work continues in the study presented in this paper –they are aimed at expanding the simulation functionalities and allowing to conduct a training for the ultrasound examination. In many previous studies, it was proven that possibility of tracking the user's movements allows the simulation realism to be improved. It is a result of the phenomenon of immersion of the user in the virtual world. The immersion improves quality of the conducted virtual training and allows to better use the abilities learned during the course. In case of the ultrasound scanner, it is necessary to track both the position and the orientation of the device head, for proper generation of the virtual image of the insides of the human body. The paper discusses a process of adaptation of a head used in the ultrasound scan to application in the training simulation. Process of preparation and adaptation of the head geometry was described, along with a process of preparation of virtual and then physical prototypes using the 3D Printing technology. The prepared prototypes were covered with markers of the optical tracking system. Proper arrangement of the markers was implemented in the database and scenarios of work were prepared, to check correctness of gathering information about the ultrasound scanner head orientation and position in the three-dimensional space. Developed solutions were verified on a test group of users. Obtained results were presented in a form allowing their easy interpretation.