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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.

Growing age and different conditions often require the replacement of orthoses, and FDM-based 3D printing can produce them quickly with less investment. In today’s market for orthotics, these characteristics are highly desired. Therefore, this study is fully focused on the optimization and strength analysis of FDM 3D-printed ankle–foot orthoses (AFO) fabricated using PLA and PLA reinforced with carbon fiber (PLA-C). An increase in ankle plantar-flexor force can be achieved by reinforcing thermoplastic AFOs with CFs. Specially designed mechanical strength tests were conducted at the UTM to generate force–displacement curves for stored elastic energy and fracture studies. The mechanical behavior of both AFOs was predicted with the help of an FEA. The model predictions were validated by comparing them with mechanical strength testing conducted under the same loading and boundary conditions as the FEA. In both the prediction and experimental analysis, the PLA-C-based AFOs were stiffer and could withstand greater loads than the PLA-based AFOs. An area of high stress in the simulation and a fracture point in experimentation were both found at the same location. Furthermore, these highly accurate models will allow the fabrication of AFOs to be improved without investing time and resources on trials.

Designing individualized medical devices requires the collection of anthropometric data from the patient. This can be done by using the 3D scanning process. Despite many advantages, it has significant drawbacks, limiting the suitability of its use for many types of medical devices. This paper presents the design of measuring station that allows to increase the quality of anthropometric data obtained in the scanning process of humans limbs. Accuracy and repeatability of data obtained on the station is presented and compared to reference scans. What's more, thanks to the automatisation of certain activities in the scanning process, operating the device requires the operator to have much lower competencies and workload.

The paper presents experimental process of manufacturing individualized prosthetic sockets out of thermoplastic material, using an additive manufacturing technology of Fused Deposition Modelling. The patient is an adult male with an amputated forearm. His stump was 3D scanned using a low-cost 3D scanner in a semi-automated manner. Then, the anthropometric data was used for creation of a model of a prosthetic socket, which was then manufactured. Three different 3D printers were used, with three different materials (ABS, nylon and PC) and three different sets of process parameters. The paper contains descriptions of the process, its results and opinions by the patient, leading to selection of an optimal process course variant.

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.

This paper presents the results of experiments conducted on a batch of additively manufactured customized prosthetic sockets for upper limbs, made of thermoplastics and designed automatically on the basis of a 3D-scanned limb of a 3-year-old patient. The aim of this work was to compare sockets made of two different materials—rigid PLA and elastic TPE. Two distinct socket designs with various mounting systems were prepared. To find a reliable set of parameters for cheap and stable manufacturing of usable prostheses using 3D printers, realizing the fused deposition modeling (FDM) process, sets of sockets were manufactured with various process parameters. This paper presents the methodology of the design, the plan of the experiments and the obtained results in terms of process stability, fit and assessment by patient, as well as strength of the obtained sockets and their measured surface roughness. The results are promising, as most of the obtained products fulfil the strength criteria, although not all of them meet the fitting and use comfort criteria. As a result, recommendations of materials and process parameters were determined. These parameters were included in a prototype of the automated design and production system developed by the authors, and prostheses for several other patients were manufactured.

Pre-operative preparation of the surgeon is more and more often extended to individual patient's anatomical models depicting the ill organ and the existing change in relation to the surrounding structures (e.g. blood vessels). Among the models there are models of the skeletal system, to which the FFF technology is used. Models of parenchymal organs are more difficult to reproduce due to material limitations in FFF technology, which is why alternative technologies such as PolyJet and SLA are used. Due to the high price of models, they are less frequently used in, especially in Polish hospitals. The research presented in the article deals with the subject of modification of the existing methodology of rapid production of pre-operative models with the use of various low-budget techniques of rapid manufacturing, which use materials of low hardness, similar to human soft tissues. The aim is to create a methodology and determine the parameters of materials that allow for the cheap production of functional pre-operational aids.

The paper presents design and manufacturing process of an individualized wrist orthosis. The patient’s upper limb was 3D scanned and the orthosis was design using a CAD system. Each part of the orthosis consists of two different materials, that fulfill different functions. By using the double-head Fused Deposition Modelling machine it was possible to produce theses parts in a single process without the need for additional assembly operations. The orthosis has been tested for mutual fit of parts, strength and comfort of use.

The paper presents results of research conducted on a batch of additively manufactured individualized openwork wrist&ndash, hand orthoses made of thermoplastics and designed automatically based on 3D-scanned geometry of a given patient. The aim of the work was to establish an automated design process and find a reliable set of parameters for rapid and affordable manufacturing of usable orthoses on popular 3D printers, with little or no supervision of the process. The paper presents motivations, methodology of automated design, plan of manufacturing and testing, the obtained results in terms of process stability, fit and assessment by patient and strength of the obtained orthoses. Almost 100 manufacturing processes of ready-to-use orthosis parts were carried out in a controlled environment and their results were analyzed thoroughly. The results are promising, as most of the obtained products fulfil the strength criteria, although not all of them meet the economic criteria. As a result, a recommended set of process parameters was determined. These parameters were included in a prototype of the automated design and in a production system developed by the authors.

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.

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.

Inter-operational surgery supplies manufactured additively using the FDM (Fused Deposition Modelling) technology are required to be sterilized before use. After manufacturing, the part should be sterilized using one of commonly used processes, without losing its dimensions and shape. The paper presents studies on manufacturing and sterilizing samples made out of ABS material and influence of the sterilization process on the dimensional accuracy of these samples.

A new approach to product quality assessment taken by manufacturers integrates environmental aspects. Design for the environment, also referred to as ecodesign or sustainable design, is an innovative approach to the traditional design process. It focuses on compliance with ecological standards at an early stage of design in CAD 3D environment. In this paper, main objectives of the ecodesign process automation method based on a CAD 3D system are presented. The ecodesign process of a small household appliance is analyzed. The main features of a dedicated software application with a graphical interface, which runs independently of the CAD 3D system, are presented.

Realism of a Virtual Reality simulation can be improved by use of physical objects tracked in real time. The paper presents possibility of using low-cost FDM process, realized by MakerBot Replicator 2X machine, in comparison with a professional one to build tooling for a simulation of ultrasound examination procedure. The objects were manufactured on two different machines out of ABS material, 3D scanned for accuracy testing and finally possibilities of their use in a VR system were evaluated.

The paper presents design and manufacturing process of an individualized ankle orthosis using additive manufacturing technologies and reverse engineering. Conventional processes of manufacturing of orthosesareexpensive and time consuming -an alternative method was proposed. The patient’s leg was 3D scanned and the orthosis was designed using a CAD system. It was then manufactured using the Fused Deposition Modelling technology, assembled and fully tested. Positive results were obtained.

This paper describes prototyping of an individualized cosmetic arm prosthesis. Aim of the studies was to obtain an anatomically correct, lightweight prosthesis. It was accomplished using additive manufacturing technology of fused deposition modeling. The data was obtained by 3D scanning. An experimental concept of dual extrusion of two different materials was applied – the prosthesis was divided into an elastic shell and a rigid core, manufactured in one process. Obtained results were positive.

This paper presents assessment of the Rapid Prototyping finishing techniques for the printed components. The aim of the study was to compare the element printed with FDM technology before and after the treatment, using 3D scanning techniques. The object was scanned right after manufacturing, then was subjected to finishing treatment and was 3D scanned once again. Assessment of the results was performed using the GOM Inspect software, based on a comparison between scans and nominal model.

The paper presents development and studies of an intelligent CAD (Computer Aided Design) model of an openwork wrist orthosis. The key feature is customization capability on the basis of shape and size of patient’s hand and arm. A patient is first 3D scanned using a cheap structured light scanner. Then, the gathered anthropometric data is used as a base for automated adjustment of geometry of an intelligent model of a wrist orthosis. Finally, the orthosis can be 3D printed using low-cost machines. Automation of design eliminates a need of manual processing of 3D scans and 3D models, as the model automatically adjusts itself to patient’s data and is ready for manufacturing. The paper presents basic concepts, development and studies on such a model. The studies comprised of collision analysis between an automatically generated orthosis and patient’s own hand and arm, as well as manufacturing examples of orthoses and fitting them to real patient’s hand. The results are generally positive, but further development is required to obtain optimal results for great majority of patients.

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.

In this paper, the application of multi-agent system to support decision-making process in design for recycling is presented. The design for recycling term is highlighted either as the design problem or from the point of view of regulations. The structure of agent system supporting the designer during the design process is showed. The basis of special kind of product model, that is the extension of standard 3D product model, called recycling-oriented product model, is described. The example results of analysis, based on real household appliance model, are presented.

The paper focuses on issues associated with the ecodesign of household appliances. The authors describe the estimation of recycling cost of end-of-life products using their original system supporting ecodesign. The cost estimate was conducted during product design stage using the information stored in CAD 3D system. A sample estimate was made for a washing machine, fridge, kettle, and a hairdryer.

This paper presents practical results of a new, open approach to knowledge formalization and management in Virtual Reality applications for use in industry, especially in design and training purposes. Idea of applications with open access to knowledge is presented. Three cases of VR systems are shown – two for the design and one for training, all implemented in industrial companies in Poland. The focus is put on concepts of storing and easy editing knowledge in the applications, in a way to ensure self-sufficiency of applications in a given company after deployment. Dedicated tools for knowledge edition are presented, along with selected results of their implementation in scope of effectiveness of expanding the knowledge base.

One of the key aspects of Industry 4.0 is high automation of various processes conducted through product lifecycle. In the article the authors consider the issue of final stages of product lifecycle and the automation of product assessment from ecological point-of-view in the context of Industry 4.0. The automation of product assessment is conducted by set of measures, calculated from special type of product model called Recycling Model of Product, that is also showed in the paper. The Recycling Model of Product and the assessment are conducted using dedicated module, operating in CAD 3D system environment. The assessment of example product is presented in the paper as well.

The paper presents possibility of using a low-cost Fused Deposition Modelling process, realized by MakerBot Replicator 2X machine, in comparison with a professional one – realized by Dimension BST 1200 machine – to build tooling for an innovative training simulation, in accordance with Industry 4.0 guidelines. A physical object was manufactured and then tracked to manipulate in a virtual environment – it was a manual head used during the procedure. The objects were manufactured on two different machines out of ABS material, 3D scanned for accuracy testing and finally possibilities of their use in a VR system were evaluated.

Timely delivery of products designed to individual requirements of customers is increasingly difficult for manufacturers. It results from difficulties in effective development of production schedules and material flow control. The reason is, among other things, the lack of real data on standard times required to complete individual manufacturing processes. This article presents the assumptions on the method of estimating standard times for highly individualized products. The proposed method has been incorporated into computer software that was verified at an actual production company that manufactures electric heating elements.

The main problem addressed in this paper is the use and evaluation of low-cost additive manufacturing (3D printing) techniques and CT images as tools for manufacture of usable and individualized, anatomically correct models, assisting surgeons in their daily work. The authors formulate own methodology of design and additive manufacturing of medical products on the basis of medical imaging data. A specific case was selected—a surgical lower jaw template for use in the middle of operation. Two Fused Deposition Modeling machines—professional and low-cost—were used to manufacture the same product, which was later evaluated, inspected for accuracy (by 3D scanning) and used during the surgery. By two 3D printing processes comparison it was found that the low cost comes at a price of lower accuracy and increased demand for process supervision. The authors obtained a fully usable medical product used during an actual reconstruction surgery. Partial clinical results are presented—use of 3D printed templates helped reduce surgery time and generally improved the patient recovery process.

Numerous experimental studies, including experiments performed by the authors, have shown that the part orientation during layer deposition has a very strong influence on final strength of a product manufactured by additive Fused Deposition Technology. The paper presents the results of tensile, bending and impact strength tests performed on samples of various orientations, made out of ABS material using FDM technology. The results of these tests allowed discovering a unique phenomenon – with the changing orientation, not only the values of strength indexes change, but macroscopic material behavior under load as well. The transition between a “yield point” and “brittle” material usually happens in a certain range of orientation values, named a critical orientation by the authors. The paper indicates supposed ranges of critical orientation for various types of loads.

Received: 23 January 2015 Abstract Accepted: 8 February 2015 In the paper the issue of ecological-oriented product design is addressed. The definitions that concern product design are listed and the factors that make them important for the manufacturers are indicated. The method of ecological-oriented product assessment during the design process (implemented in the 3D CAD system), drawn-up by authors, is used for the analysis. The assessment of real household appliance using the method is presented and the conclusions from the evaluation are drawn.

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.

The paper presents a method, developed by the authors, for manufacturing polymer composites with the matrix manufactured in a layered manner (via 3D printing – Fused Deposition Modeling) out of a thermoplastic material. As an example of practical application of this method, functional prototypes are presented, which were used as elements of foundry tooling – patterns for sand molding. In case of manufacturing prototype castings or short series of products, foundries usually cooperate with modeling studios, which produce patterns by conventional, subtractive manufacturing technologies. If patterns have complex shapes, this results in high manufacturing costs and significantly longer time of tooling preparation. The method proposed by the authors allows manufacturing functional prototypes in a short time thanks to utilizing capabilities of additive manufacturing (3D printing) technology. Thanks to using two types of materials simultaneously (ABS combined with chemically hardened resins), the produced prototypes are capable of carrying increased loads. Moreover, the method developed by the authors is characterized by manufacturing costs lower than in the basic technology of Fused Deposition Modeling. During the presented studies, the pattern was produced as a polymer composite and it was used to prepare a mold and a set of metal castings.