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The technique joining by forming allows the structural integration of piezoceramic fibers into locally microstructured metal sheets without any elastic interlayers. A high-volume production of the joining partners causes in statistical deviations from the nominal dimensions. A numerical simulation on geometric process sensitivity shows that the deviations have a high significant influence on the resulting fiber stresses after the joining by forming operation and demonstrate the necessity of a monitoring concept. On this basis, the electromechanical behavior of piezoceramic array transducers is investigated experimentally before, during and after the joining process. The piezoceramic array transducer consists of an arrangement of five electrical interconnected piezoceramic fibers. The findings show that the impedance spectrum depends on the fiber stresses and can be used for in-process monitoring during the joining process. Based on the impedance values the preload state of the interconnected piezoceramic fibers can be specifically controlled and a fiber overload.

Process monitoring and controlling with detailed real-time information such as the cutting force is required for improving the performance of milling processes. This paper presents a novel system for measuring the cutting force in the direct vicinity of the indexable insert. The outlined concept makes use of piezoelectric thick film sensors mounted directly below the insert. The unique design and features of the new sensor enable accurate and continuous force measurements as well as the indication of wear. The results of the experimental investigations are presented and compared to results of a conventional dynamometer.

Background The modularity in total hip arthroplasty (THA) allows orthopaedic surgeons for an exact reconstruction of hip biomechanical parameters especially in revision and tumor arthroplasty. Modular structured femoral stems using taper junctions showed increased implant breakage in the recent past. Presentation of the hypothesis We hypothesize that a novel modular stem-neck-interface leads to less implant breakage compared to conventional femoral stems. Testing of the hypothesis For this purpose, a novel modular femoral stem for THA was to design and manufacture. Therefore, three different variants of interface mechanisms were developed that enable a simple connection between the stem and the neck modules and allow for intra-operatively adjustment. Three prototypes A, B and C were manufactured and subsequently dynamic fatigue (ISO 7206–6) and body donor tested. Implication of the hypothesis Modularity in THA is mainly applied in THA as well as in revision and tumor arthroplasty. Modular implants are barely used because of the high risk of breakage. Another risks in this context are taper fretting, corrosion and disconnection. With the novel design, it should be possible to detach the stem and neck module intra-operatively to adapt the anatomical situation. The novel coupling mechanism of the rotating interface seems to be the most suitable for a secure stem-neck connection and is characterized by good intraoperative handling.

The effects of signal frequency as well as curing time and moisture content on the dielectric properties of concrete have been investigated. Microwave dielectric material characterization was performed on two ordinary concrete mixtures varying in their aggregate composition and water-to-binder ratio (w/b). Moisture content, complex permittivity and signal attenuation behavior were evaluated in the GHz range over a radio frequency range of 1 to 10 GHz at ages of 28 and 100 days. The results serve as useful information for the spectrum planning of 5G networks in the sub-6 GHz frequency band. The investigations show a strong correlation between the dielectric parameters and moisture content, as well as the internal pore volume of the samples under investigation. With ongoing curing time, the dielectric number decreases steadily due to hydration-related water consumption and evaporation.

Additive manufacturing of Nd-Fe-B is a novel approach for the fabrication of permanent magnets. We present an analysis of the magnetic properties and microstructure of Nd-Fe-B permanent magnets, which were produced by laser powder bed fusion (LPBF). By optimization of processing parameters for the Nd-lean powder coercivity of 921 kA/m (1.16 T), remanence of 0.63 T and maximum energy product of 63 kJ/m3 are achieved without the addition of further Nd-rich low-melting alloys or any other post treatment. Thereby, remanence and maximum energy product represent the highest reported values for additively manufactured permanent magnets. The impact of area energy density EA on the magnetic properties is discussed. The isotropic microstructure consists of short Nd2Fe14B dendrites at the melt pool boundaries and globular sub-micron sized grains in the melt pool interior. After LPBF of the Nd-lean powder no evidence of α-Fe is found in the microstructure.

Conventional strain gauges made of constantan or CuCr for instance have a low value for structural health monitoring issues in plastic composites. These strain sensor materials exhibit small elastic regions and show fatigue when dynamically loaded with strain levels over 0.3 percent. For this reason, these sensors would break or fail before the composite life-time and thus cannot be integrated into this kind of composite materials. Pseudoelastic thermal shape memory alloys are therefore used as strain sensors and integrated into composites in order to allow piezoresistive strain measurement and structural health monitoring in such materials. Thermal treatments are used to create sensor structures out of shape memory alloy wires. Pseudoelastic shape memory wires can be strained up to 8 percent repeatedly. Their gauge factor is higher than 5. Shape memory strain sensors are successfully embedded into glass fibre reinforced plastics and show a significant and reproducible resistance change when the composite is strained. The dynamic strength is magnificently higher compared to conventional strain gauges. Shape memory strain sensors are an efficient alternative to fiber-bragg-grating sensors and can potentially be used for strain measurements in different plastics and textile materials. Shape memory sensor structures can be embedded or applied and are good candidates for structural characterisation and monitoring applications.

Nowadays, smart materials, such as Shape Memory Alloys (SMA) are examined as actuators for flexible, adapting shapes and structures of soft robotics. However, several limitations such as long response times, the possibility of unintended actuation as well as structural fatigue are still present and obstructive for their utilization. For applying these actuators in field of robotics, this results in a reduction of reliability (e.g. position accuracy as well as repeatability) and safety of the overall system. To encounter this, the paper presents a method for automatic fault detection for SMA. Also an approach of fault-tolerant control will be discussed. The methods aims to ensure the operability of the overall system, comprising multiple SMA actuators even in case of significantly changed system parameters or failure of single actuators.

Lightweight design based on fiber reinforced plastics (FRP) has potential for improvement by integration of sensors and actuators made of smart material filaments. Regarding FRP with integrated actuating shape memory alloy (SMA) wires, this paper presents important characteristics of such an adaptive composite and its components for design purposes. Beyond that, the first successful pultrusion processing of sensing SMA wires is proposed to address lightweight design mass production for safety-related applications. Measurements of this smart composite structure with strain sensor functionality proved high sensitivity compared to conventional sensors.

Due to a combination of different classes of materials, intrinsic hybrid composites are characterised by high strength and low weight. The mechanical properties of hybrid parts are mainly determined by the interface between the different materials. Consequently, this interface has to be considered in detail within the development of an intrinsic hybrid composite. The general approach of the considered composite is the combination of a mechanical form fit with adhesive bonding. This contribution focuses on the development, production and characterisation of the interface between aluminium and a fibre reinforced polymer as well as of the hybrid composite.

Sandwich materials offer high stiffness in combination with small weight. Functional integration allows for additional active and passive functionalities. The paper deals with sandwich materials with sensor and actuator functionality using integrated piezoceramics. The challenges in production are examined in the paper by experiments and numerical simulation. In order to enable the sandwich material for forming, the adhesive properties are highly significant. An appropriate process chain is developed for manufacturing a semi-finished part with integrated piezoceramics which is suitable for forming.

The FED method (Fixation, Elongation, Derotation) is a treatment method approach to Patients with scoliosis. The FED method is especially established in Spain and Poland, whereby in Germany it is less well-known. Nevertheless the FED method is within the scope of a research project (Project Number: 19200 BR/3). The purpose of the paper is to characterize the FED method and to highlight the specificities in contrast to the Schroth method, which is international established and especially in Germany.This systematic literature research was conducted in Nov 2017-Jan 2018. Therefore common medical and physiotherapeutic databases were used. Furthermore there was a hand search in selected scientific journals. Only a small number of relevant references were identified. That is why the respective authors were asked to provide the full-texts of their papers and to recommend further references.A total of 378 references were identified. After removing duplicates and the content-related selection, 19 references were deemed to be relevant. Based on the analysis of this relevant literature, the FED method was comprehensively characterized. First of all the general structure of the FED method and the scientific evidence for its effectiveness was described. And as a result of the literature research, the operating principles of the FED method were pointed out. Then these operating principles were discussed in comparison with the Schroth method. The Schroth method based on sensomotoric and kinesthetic principles and the correction of the pathologic posture was performed by selective muscle activation and breathing-pattern. Thus, the posture correction will be performed by the patients (auto correction). Compared to the Schroth method, the FED method implements the posture correction by the FED-device. This correction is influenced by mechanical forces with a comparatively high strength and intensity. The repetitive mechanical correction stimulates the sensomotoric system. And due to trophic/biochemical adaptations, the physiological bone growth will be stimulated.In total the authors want to clarify, that both treatment methods (Schroth method, FED method) supposed to be applied in consideration of the preconditions of the patients and the pursue of the different treatment goals. Thus, the implementation of treatment methods should be used according to the individual treatment demand and on different stages in the treatment process.Die FED-Methode (Fixation, Elongation, Derotation) wird vor allem in Spanien und Polen zur Behandlung von Skoliose eingesetzt. Die FED-Methode wird in einem aktuellem Forschungsprojekt (Förderkennzeichen: 19 200 BR/3) beforscht. Mit dem Ziel, die in Deutschland eher unbekannte FED-Methode zu charakterisieren und deren Besonderheiten zu verdeutlichen, wurde eine systematische Literaturrecherche durchgeführt.Die systematische Literaturrecherche wurde von November 2017 bis Januar 2018 durchgeführt unter Verwendung gängiger Literaturdatenbanken und einer Handsuche. Da nur relevante Literaturstellen identifiziert wurden, wurden die beteiligten Autoren um die nicht zugänglichen Volltexte sowie um weitere Literaturempfehlungen gebeten.Insgesamt ergab die Literatursuche 378 Referenzen. Nach der Entfernung von Duplikaten und der inhaltlichen Selektion wurden insgesamt 19 relevante Literaturstellen identifiziert und der Volltextanalyse unterzogen. Die vorliegende Übersichtsarbeit bietet eine ganzheitliche Charakteristik der FED-Methode. Neben dem allgemeinen Aufbau der Behandlungsmethode und der wissenschaftlichen Evidenz wurden auf Grundlage der Literaturanalyse die Wirkprinzipien der FED-Methode umfassend beschrieben und gegenüber der Schroth-Methode abgegrenzt. Die FED-Methode verfolgt im Unterschied zur Schroth-Methode eine mechanische Haltungskorrektur mit vergleichsweise hohen einwirkenden Kräften. Die repetitive Haltungskorrektur bewirkt beim Patienten eine Verbesserung der Sensomotorik und durch trophische Veränderungen die Stimulation des gesunden Knochenwachstums.Insgesamt ist zu verdeutlichen, dass die beiden Behandlungsmethoden unter Berücksichtigung der Grundvoraussetzungen der jeweiligen Patienten eingesetzt werden müssen. Aufgrund dessen und wegen ihrer verschiedenen Zielrichtungen können diese methodisch an unterschiedlichen Zeitpunkten im Therapieverlauf bzw. entsprechend des Behandlungsbedarfs angewendet werden.

The potential of adaptronic applications has been proven in many conceptual studies. A broad use in high-efficiency branches is often hindered by the absence of an appropriate assembly method. Especially for piezoceramic foil transducers, the application on structural parts can be simplified using a semi-finished part that includes the transducer. The part is then shaped in a final forming operation. The purpose of the present study is the investigation of process limits in automated process chains for producing semi-finished parts. An adhesive is used in the process, which is only locally cured. This bi-conditioned state is achieved using cooling and heating elements. The process limits are mainly affected by the choice of temperature and curing time between adhesive application and forming operation. Several tests with a rotational rheometer were carried out to investigate the curing behavior. An appropriate process window was identified varying processing time and temperature. The results were then used to build a model of the curing behavior. A mathematical approach had to be used to find the best configuration because no sharp border exists between the two adhesive conditions of liquid and solid state. The process parameters were proven with runs inside and outside of the process limits.

Nowadays, many industries have to distinguish themselves from other players in the market through innovative products and product designs. This also concerns aerosol cans. Therefore, suppliers seek solutions for producing individualized cans by embossing brand logos. Due to the almost fully exhausted deformation limits during the production of aerosol cans, this is hardly possible via conventional forming processes. As a high-speed technology, electromagnetic forming is a very promising method for overcoming the manufacturing limits of conventional processes. The paper shows a design for a tool for embossing aerosol cans. It gives insight into existing challenges and shows how to avoid or overcome them. An experimental verification proves the feasibility of the process and demonstrates that difficult forming operations are perfectly feasible with special forming processes like electromagnetic forming.

Vibration measurement and signal analysis methods are common to evaluate the functionality and characteristics of technical components in different industrial and scientific areas. Modal analysis for example is a standard method to characterize the dynamic behavior of a structure and enables the development of validated bone models. The state of the art of analyzing bone structures does not include the modal damping, although it has a significant influence on the dynamic characteristics. Within the presented investigations, the modal analyses have been performed contactless with respect to excitation and response acquisition, which implies that there are no influences of shakers or sensor couplings. Therefore, an automatic impulse hammer and a 3D Scanning Laser Doppler Vibrometer were used for excitation and response detection. Various supports of the test specimens, surface pretreatments, excitation points and excitation impulses were examined to optimize the measurement setup and process. Experimental modal analysis data were analyzed by curve fitting methods to determine the modal parameters. To evaluate different structures and effects of damping, 3D printed artificial bones and animal in vitro bones were used to perform the measurements. To produce the cortical layer of the artificial bone models, volume models were generated based on medical image data and printed by polyamide-based selective laser sintering. The cancellous bone was represented by different foam fillings for the artificial bones. Thereby, the variation of the porosity was achieved by using different mixing ratios of polyurethane foam and hardener. Furthermore, the modal damping parameters were determined from the measurement of animal bones. The measurement time was optimized during the practical implementation of the parameter determination to minimize the influence of drying and decomposition processes on the measurement results.

Digitization is the defining innovation driver for value creation in the modern global industrial society. At the forefront stand the increase in efficiency for flexibilization and improved resource utilization provided by the self-optimizing automation of processes. Digital technologies must become inherent components of the production system.

When applying a magnetic field parallel or perpendicular to the long edge of a parallelepiped Ni-Mn-Ga stick, twin boundaries move instantaneously or gradually through the sample. We evaluate the sample shape dependence on twin boundary motion with a micromagnetics computational study of magnetic domain structures and their energies. Due to the sample shape, the demagnetization factor varies with the direction of the external magnetic field. When the external magnetic field is applied perpendicular to the long edge of the sample, i.e. in the direction in which the demagnetizing field is highest, the magnetic energy intermittently increases when the strength of the applied magnetic field is low. This energy gain hinders the twin boundary motion and results in a gradual switching, i.e. a gradual magnetization reversal as the applied magnetic field is increased. The formation of 180° magnetic domains offsets this effect partially. In contrast, when the applied magnetic field is parallel to the long edge of the sample, i.e. in the direction in which the demagnetizing field is lowest, the energy decreases with each subsequent magnetization domain reversal and the twin boundary moves instantaneously with ongoing switching. The actuation mode with the field parallel to the long sample edge lends itself for on-off actuators whereas the actuation mode with the field perpendicular to the long sample edge lends itself to gradual positioning devices.

This paper presents experimental results of a novel approach for measuring the forces in forming machines. The basis for this approach is the development and arrangement of a modular measuring system which can be integrated between tool and ram of the forming machine. The modular character of the system allows it to be applied to any tool size and shape. A special focus of the application presented here is the recording of the surface and temporal distribution of the forces and their significance with regard to component quality. In this way, it can be shown how changes in the process affect the distribution of force, for example by deliberately detuning the tool. In addition, statements on time and place can be derived from possible crack formation. In this way, the measuring system can be used for continuous process monitoring.

Background: At present, there are no meaningful and sophisticated computer games that simultaneously allow the treatment of movement disorders such as Parkinson's syndrome. In particular, there are no systems to consider the severity of the disease and the physical skills of the patient. Methods: A computer game using the Microsoft Kinect as markerless sensor for the 3 D recognition of the patient's movement was developed to support the rehabilitation. The scenario of a basketball game was created after determining that the movement like throwing a ball and the correct posture of the body are important. A study based on system usability was performed with 15 patients to evaluate the system. Results: The technical feasibility of a computer-assisted training system for supporting patients with Parkinson's disease has been demonstrated. No markers on the patient are required for movement detection and allow a user-friendly handling. Regarding the usability study, the patients were accepting of such a system and its at-home use and symptoms like 'freezing' and the Pisa syndrome can be treated. Conclusions: The physiotherapist can be assisted by the developed rehabilitation system. An objective measurement of the patient's training progress delivers valuable information to adjust the training sessions for every patient individually. Due to its modular character, the system can also be applied to other diseases or sports injuries and offers the basis for further development.

This paper shows a comparison of existing self-pierce riveting technologies with the newly developed self-pierce riveting with solid formable rivet (SPR-SF) for the joining of Aluminum die casts. The challenges during the mechanical joining of the Aluminum die cast AlSi9Mn by different joining technologies like self-pierce riveting with semi-tubular rivet (SPR-ST), self-pierce riveting with moveable die element and semi-tubular rivet (S-SPR-ST), self-pierce riveting with solid rivet (SPR-S) and self-pierce riveting with solid formable rivet (SPR-SF) will be discussed and the joining technologies in regard to process force, interlock, shear tensile strength and top tensile strength will be analyzed.

The application of ultrasonic vibration assistance in machining offers many benefits over conventional machining. In some machining processes, like the generation of geometrically defined microstructures by cutting, the interaction of the system components and the machining process can be particularly crucial with respect to the production result. Monitoring of ultrasonic vibration-assisted machining in terms of the in-process measurement of frequency and amplitude is currently realized by measurement inside the actuator; thus, measurement is presently undertaken relatively far away from the cutting process. In this paper an in-process measurement set-up based on strain gauges positioned close to the cutting edges is presented. It is used to investigate the induced vibration in the ultrasonic horn. Experiments on machine samples with and without ultrasonic vibration assistance are performed using the in-process measurement set-up described. The results of the strain gauges are analysed in comparison to internal feedback signal and surface measurements. The experiments show the high sensitivity of the measurement set-up presented and a huge gain of information compared with the conventional measurement approach. This enables improved controllability of the excited mode shapes as well as in-process adjustment of the ultrasonic vibration frequency and amplitude for the manufacturing of defined microstructures.

A major issue by implementing ball screw drives in machine tools is the occurrence of transient thermal fluctuations in normal operation leading to unsteady thermal distortions, especially at highly variable feed rates. One way to overcome this issue and thereby improve the thermoelastic machine performance is through thermal management solutions. The objective of this work is the reduction of temperature fluctuations by increasing the thermal inertia of ball screws. For this aim, a latent heat storage unit was designed based on phase change materials. In addition, a thermal resistance network was developed for evaluation of the ball screw behaviour. Functional validation of the developed system was carried out on a ball screw test rig.

This article deals with improving the planning of hem flange bonding in the car body manufacturing process. Particularly during the ramp-up of the plant, great effort is put into ensuring that the generated adhesive bond meets the quality requirements. Here, several challenges occur in parallel. This ranges from the specific adhesive design, a result of multi-dimensional and individually curved car body parts, to the multi-stage process chain, where the associated manufacturing equipment is complex. This intricacy is countered by a discrete analysis of the adhesive continuum. Based on an established method, the location where the adhesive must be applied is computed under consideration of contiguous contours, disturbance variables and applicability by the projected dispensing system. For this reason the performance of the involved machines is examined. The results of this new method comprise a robot path along which an application system is guided, and control commands for the latter. Finally, a validation proves that this way, the adhesive application can be designed in a shorter period of time and in high quality at an early stage of plant design.

Research and development for industrial applications forces Fraunhofer IWU to explore new fields of technology. The combination of Media Based Forming and Injection Molding (MBF-IM) in a single process is such a new development to meet the requirements on lightweight design and resource efficiency. Based on over 20 years of Fraunhofer IWU experience in hydroforming, this technology development started with the usage of metal tubes and PA6 with glass fiber to produce metal-plastic-hybrid-components the structural strength of the component is realized by the formed metal tube while the molded attachment allows for easy functionalization. Cockpit cross beams (CQB) are known state of the art components produced this way. In a first development step the conventional hydroforming process was replaced by media based forming (MBF) using nitrogen as a pressure medium. With this process the tool can always be kept dry for the injection molding (IM) process without any additional effort, and no subsequent part cleaning is necessary. Together with TU Chemnitz and industrial partners further developments are continuously carried out and still under research. The focus of this strategic cooperation is the development and the usage of plastic tubes for the structural function of the component. The paper shows the development path from the state of the art for the MBF-IM from metal-plastic hybrid components to the replacement of the liquid active medium for the MBF by gaseous nitrogen, the use of endless fiber-reinforced plastic tubes as semi-finished products to the MBF-IM of short-fiber-reinforced plastic tubes.

Today, biological transformation is considered as a new emerging frontier in the evolution of digitalization and the Fourth Industrial Revolution (Industry 4.0). The principle of biologically inspired intelligent manufacturing is proposed to be a driver and factor for sustainable development of new materials, design concepts, processes and equipment as well as production systems. The potential of utilizing biological principles can be considered for innovative lightweight environmentally friendly and energy efficient industrial products, mainly by using, being inspired by or by imitating biological elements, solutions, phenomena, materials, or living creatures. The combination of biological principles with digitalization, new technologies and new processes provides an excellent tool for sustainable and resource efficient production. This paper presents and discusses examples of research and development directions as well as industrial products. Few examples of multifunctional metal-based parts, molds and dies with optimized and efficient cooling channels, inspired by nature, were designed and produced, including new processes such as additive manufacturing.

Foldable technical structures can be used to provide a temporary additional volume. In nature, a tubular folding application is the extension of the snail eye. The present study uses this approach. A transformation into a technical application is only successful if the high eversion loads are considered. The study aims to develop a method to realize such structures based on a metallic wire net structure. The tube consists of Shape Memory Alloy (SMA) pieces connected by developed crimp elements produced by additive manufacturing. Additive manufacturing was used to provide a fast and effective way to make several crimp element geometries available to define a preferred variant. In a preliminary building study, the printing parameters for crimp element production were improved. The tubular structure development is assisted by numerical simulation of the eversion process. The SMA material model parameters were identified with experimental tension tests. A feasible way to connect additively manufactured crimp elements with SMA wire was found within a joining method study. Tension tests of the connections protect against pull-out failure. The eversion process was investigated using a high-speed camera system. Multiple eversion of the developed structure is possible without failure.

Additive manufacturing (AM), often referred to as 3D printing, is a generic term describing the layered build-up of material in near net shape frequently attributed with a freedom of design that cannot be achieved otherwise. AM focuses basically on the fabrication of parts for different fields in complex high-tech applications. Examples include components for jet engines, turbines blades, and implants in the medical sector. This is often justified with tool cost savings, shorter lead-time, and overcoming the “design for manufacture” paradigm. On the other hand, a machining allowance is frequently required to counteract the inherent surface roughness and the widespread challenge of part distortion due to residual stresses. At this point, geometrical complexity and small batch sizes transform into strong cost drivers compared to conventional subtractive processing. In fact, these parts are simply hard-to-clamp and hard-to-probe. Moreover, iterative processing is frequently required due to remaining residual stresses in order to reach the target geometry; even the part envelope changes unintentionally. The current paper explores the novel approach of semiautonomous postprocessing of AM parts and components based on flexible clamping, geometry acquisition in the as-clamped position using cooperating laser profile sensors, and an adaptive milling path planning strategy to counteract unforeseen change of the part envelope.

This article deals with an experimental and numerical study of the inductive heating of glass fibre (GF)-reinforced thermoplastics with susceptors made of stainless steel that are embedded in them. The objective of this article is to examine the links between individual process and system parameters and the heating behaviour of fibre-reinforced plastics. Two different susceptor designs were tested in relation to their heating capability. Furthermore, it was possible to experimentally study the dependency of the space between the specimens and inductors and therefore the impact of the generator output of the induction system and inductor attachments differing in their geometric shapes in terms of heating. Moreover, it was possible to use numerical simulation to examine the heating behaviour at different frequencies. These findings indicate that it is possible to heat GF-reinforced semi-finished products by fibre-shaped susceptors. Finally, it was possible to demonstrate that the heating process can be designed by means of the frequency of the induction system and directly controlled using the generator output.

The paper presents research concerning the utilization of shape memory alloys in terms of an antagonistic actuator system. The main focus is to determine arrangements for the necessary movements and also to evaluate a suitable control methodology. Most use cases of soft robotics can be accomplished by either linear actuators (cf. earthworm), circular actuators (cf. brachial joint) or a combination of both. Hence, for the research, those two scenarios were taken into account. The paper describes the used simulation model, which bases on a thermo-mechanical submodel of a single SMA actuator. It complements interconnections of physical parameters like temperature, percentage of martensite, elongation and tension. Furthermore, it is shown, how the submodels are connected in a suitable way to establish the required use cases.The position control of either the transversal position or the angle is realized by a PID or PI controller. The paper also shows the impact of parameter changes in the SMA on the achievable position accuracy. Also different strategies for controller design will be discussed.

The so called Impulse Decoupling possesses an outstanding potential to increase the dynamics and accuracy of direct linear drives. However, such systems still require an additional magnetic sensor and extra linear guidance. This paper presents a novel design approach for decoupled drives which necessitates rather minor cost effective modifications. The guidance are substituted by elements that cover guidance and decoupling function and the sensor can be omitted under certain circumstances. In order to evaluate the approach a drive axis is designed and experimentally investigated. A comparison with conventionally designed direct linear drives shows the proof of the concept.

The integration of active piezoceramic sensors and actuators into passive sheet metal assemblies produces smart structures. Smart structures are capable of sensing the condition of parts and systems as well as interacting with the environment. Today, smart sheet metal parts are manufactured by surface bonding of sensors and actuators on shaped structural parts. This paper presents a technology for the direct structural integration of lead-zirconate-titanate (PZT) fibers. The fibers are integrated in flat sheet metal, which is subsequently shaped by forming. Microcavities are formed into the surface of the flat metal sheet in which the piezoceramic fibers are inserted and joined. After that, the composite is shaped into a complex 3D surface by deep drawing. The production technology is discussed in detail with regard to the limits of each process step. Functional prototypes with ten interconnected parallel piezoceramic fibers were fabricated. The function as actuator and sensor for ultrasonic elastic waves is demonstrated and the degradation due to the shaping is compared for different parameters of the deep drawing process. The composite shapes are cups with a double curvature radius of 100 mm and 250 mm respectively. As a result, degradation of the piezoelectric function varies with the process parameters. In the case of a double curvature of 250 mm, a degradation of the transducer function of 20% was shown in the experiments. The cause of the decreased performance after shaping is discussed and explained by debonding mechanisms. Results of numerical simulations show a good agreement with the experimental findings of the optimum process parameters. Furthermore, a setup of a wing assembly segment is used to demonstrate the potential of integrated PZT fibers in shaped metal structures. The integrated fibers are used for health monitoring of a multiple bolted joint. It is shown that loosening of a single screw can accurately be detected by the directly integrated PZT fibers.

In this paper we present an approach to reset a preload loss in ball screw drives which enables to compensate losses of positioning accuracy due to wear over lifetime. The main purposes are reduced maintenance, longer service life and improved workpiece quality by regenerating the desired preload conditions which leads to a higher profit for manufacturers. For this purpose, a novel shape memory alloy (SMA) bulk actuator module for ball screw drives is designed. The device is developed to be implemented in standard drives without major changes in component design. It is installed between flanged nut and counter nut and replaces a spacer usually needed to set a defined preload. To achieve the required actuator performance SMA bulk actuators are investigated in detail. This covers their basic design and activation concepts. A prototype is designed and experimentally investigated; measurements show the proof of the concept..

In machine tool engineering, the impact of thermal issues on machine precision and efficiency has been outlined in numerous studies. One of the major challenges is the energy-efficient distribution of heat within the machine structure. In order to control occurring heat fluxes without additional energy input into the machine tool, smart materials can be used for load-dependent adjustment of heat transfer characteristics. The present study illustrates the development and examination of heat transfer switch mechanisms using shape memory alloys. Experimental and numerical results demonstrate how different types of actuators can be used to enable an energy self-sufficient thermal switch function between heat source and heat sink. Different scenarios are considered and the combination of thermal switches with highly conductive heat-transfer devices and latent heat storages is evaluated.

This paper describes a novel approach and its realization for measuring the force distribution within a forming process. Using a modular system integrated between the ram of the machine and the upper die of the forming tool a tool independent application is possible. First metrological examinations will prove the functionality of the system with respect to the detection of process parameter changes and quality indicators. The benefit of such an approach will be shown by means of several use-cases.

The gear whine phenomenon in vehicles is a well-known acoustic issue which often needs a development of individual measures. Especially in rear- wheel and four-wheel drive vehicles, the acoustical optimization of the rear axle leads to the major goal conflict: improvement of the vibrational isolation of the rear axle versus excellent driving dynamics of the vehicle. A promising solution for this issue is described in this paper. The key objective is to reduce the noise contributions of the rear axle using an active vibration control system (AVC) based on piezoelectric actuators on the transfer path from the axle into the vehicle. In the first part of the paper, the development process of the AVC system is described. In the second part of the paper, a rear axle test bench is presented which is used to validate the simulation results. A multi component control algorithm has been implemented in order to get an optimum reduction of relevant forces at the mounting points to the vehicle using one or more actuators. In preparation for a series launch of the AVC system, an assembly concept for applying the piezoelectric actuators to the rear sub frame in a series production process is presented.

smart³ is a cross-disciplinary network focusing on innovative and meaningful applications of smart materials. The network consists of engineers, designers and economists as well as material- and social scientists collaborating with small and medium sized enterprises. As well as giving an overview on different smart materials, this conference contribution shows how engineers and designers have cooperated in creating product concepts within the strategic categories smart production, smart mobility, smart health and smart living. Design models will visualize the output of R&D projects. The smart³-network comprises a radical change of paradigms in product development by implementing smart material functions directly into the component structure. Hence functionality will already be achieved on the material level.

Die Digitalisierung ist der bestimmende Innovationstreiber fur die Wertschopfung in der modernen globalen Industriegesellschaft. Im Vordergrund steht der Effizienzgewinn fur eine Flexibilisierung und bessere Ressourcennutzung in der Produktion durch die selbstoptimierende Automatisierung von Ablaufen. Digitale Technologien mussen inharenter Bestandteil des Produktionssystems werden. Ein Cyber-Physisches System reprasentiert die angestrebte Einheit von Realitat und digitalem Abbild und ist die Weiterentwicklung der Mechatronik zu einem symbiotischen Systemansatz auf Basis der informationstechnischen Vernetzung aller Komponenten. Die Informationstechnik und auch nichttechnische Disziplinen haben eine Vielfalt an Methoden, Techniken und Verfahren hervorgebracht, mit denen sensorische, aktorische und kognitive Funktionen so in technische Systeme integriert werden, dass diese Funktionalitaten aufweisen, die bislang nur von biologischen Systemen erfullt wurden. Auf diese Weise erwachst aus der Evolution durch die Industrie-4.0-Technologien tatsachlich ein disruptiver Paradigmenwechsel. Produktion, Ausruster und Produktentwickler treten in eine neue Qualitat eines Innovationsverbundes ein.

The integration of sensors and actuators in material-compounds allows for additional functionalities within minimum space. Especially, piezoelectric materials are widely used in industrial applications, such as fuel injection or positioning. Up to now, production of sheet-metal-compounds with a sensor and actuator functionality is strongly restricted by manual fabrication processes. The design of a material-compound including aluminum sheet metals and flat piezoceramic fibers (piezoceramic-metal-compound) and a process chain allowing for an automated production offers the possibility of serial production. The compound design, the process chain for the fabrication of semi-finished parts, the forming into structural parts, and the functionality are presented. The process chain enables piezoceramic-metal-compounds for large-scale production.

Zusammenfassung Fragestellung Die Arbeit soll einen aktuellen Überblick über die konservativen Therapieverfahren (skoliosespezifischen Physiotherapie) bei Patienten mit idiopathischer Adoleszentenskoliose (AIS) im Allgemeinen liefern. Im Speziellen ist die FED-Methode (Fixation, Elongation, Derotation), welche Inhalt eines Forschungsprojektes (Förderkennzeichen: 19200 BR/3) ist, Gegenstand der Recherche. Material und Methoden Diese narrative Literaturrecherche wurde in den Zeitraum von Nov. 2016 bis Jul. 2017 durchgeführt. Die erste Recherche erzielt die Auflistung der Therapieverfahren für Skoliosepatienten, während der zweite Teil der Charakterisierung dieser Verfahren dient. Ergebnisse Insgesamt wurden 34 relevante Literaturstellen identifiziert und der Volltextanalyse unterzogen. Es existieren Behandlungsverfahren mit und ohne Autokorrektur. Zu den Behandlungsverfahren mit Autokorrektur zählen die folgenden Konzepte: Schroth-Methode, Side Shift Program, SEAS-Program, DoboMed, Lyon School, BSPTS, FITS und teilweise Klapp’sches Kriechen. Die Verfahren Vojta-Therapie, PEP-Programm, Hanke-Konzept E-Technik®, Bobath-Konzept, PNF und Riemenübungen gehören zu den Behandlungsverfahren ohne Autokorrektur. Diskussion Die Schroth-Methode ist ein grundlegendes Therapieverfahren, woraus sich weitere Verfahren ableiteten. Zur Charakterisierung der FED-Methode (Fixation, Elongation, Derotation) wurde keine Referenz gefunden. Dieses Behandlungsverfahren wurde lediglich kurz in einer Arbeit erwähnt. Schlussfolgerung Verschiedene Verfahren werden bei AIS angewendet. Diese Arbeit bietet einen Überblick über diese Therapieverfahren. Weitere Untersuchungen sollten sich mit den Wirkmechanismen der die FED-Methode befassen.

Numerical mechanical models used for design of structures and processes are very complex and high-dimensionally parametrised. The understanding of the model characteristics is of interest for engineering tasks and subsequently for an efficient design. Multiple analysis methods are known and available to gain insight into existing models. In this contribution, selected methods from various fields are applied to a real world mechanical engineering example of a currently developed clinching process. The selection of introduced methods comprises techniques of machine learning and data mining, in which the utilization is aiming at a decreased numerical effort. The methods of choice are basically discussed and references are given as well as challenges in the context of meta-modelling and sensitivities are shown. An incremental knowledge gain is provided by a step-by-step application of the numerical methods, whereas resulting consequences for further applications are highlighted. Furthermore, a visualisation method aiming at an easy design guideline is proposed. These visual decision maps incorporate the uncertainty coming from the reduction of dimensionality and can be applied in early stage of design.

This paper shows an overview of different analyses regarding current challenges at self-pierce riveting with solid rivets as well as semi-tubular rivets of lightweight materials like aluminum die casting, carbon fiber reinforced plastic and 7xxx series aluminum alloy. The joining process analyses will demonstrate the cause and the development as well as the influence on joint quality of individual joining process-induced defects. In addition, methods are described how these imperfections can be avoided or reduced.

Shape-Memory-Alloys (SMA) are suited for miniaturized drives since they possess a high specific workload and scalability. However, most SMA drives still require guidance to realize stiffness. But, there is a design approach for actuators which realize both. Here, the stiffness in the non-moving directions is achieved by the arrangement of the SMA as wire robot. This paper presents a general description of such actuators. Based on that the design of such actuators is formulated as a mathematical optimization algorithm providing a correlation between the variables for design and specification. In order to evaluate this approach, a rotary and a linear actuator are designed and experimentally investigated.

Sandwich structures consist of one light core layer and two top layers, which form the load-bearing structure. These layers have to be stiff and strong and have to protect the structure against indentations. The main task of the core layer is to keep the top layers in place and to generate a high shear stiffness. In order to obtain the required space between the top layers, the core layer has to have a high specific volume. Different sandwich materials with aluminium or steel top layers and cores of aluminium combs, corrugated aluminium sheets or aluminium foams are already known. In order to obtain better properties in terms of strength fibre-reinforced plastics (FRP) are utilised as top layers; this is the focus of numerous of the current research studies. The sole use of these materials leads to negative effects regarding the damage and impact behaviour. New top layers with high strength and high stiffness characteristics as well as good damage tolerances are to be expected by utilising metal layers in combination with endless fibre-reinforced plastics, so called hybrid laminates. These hybrid laminates combine the positive properties of metals (e.g. ductility) and fibre-reinforced plastics (e.g. tensile strength). The focus of this investigation lies on the production and characterisation of sandwich structures with aluminium foam core layers and hybrid laminate top layers. The foam cores consist of closed pore aluminium foams produced by utilising ingot and powder metallurgical techniques. The top layers consist of glass fibre-reinforced thermoplastics and aluminium layers. The production of the sandwich materials is realised by means of thermal pressing.

Lightweight solutions and functional integration become more and more important in different fields of industry. In order to achieve a sensor and actuator functionality of shaped sheet metal parts, today a generally manual application step of the piezomodule is necessary. This subsequent process is time consuming and leads to high costs. In earlier studies a method was presented allowing the fabrication of a formable compound with an integrated sensor and actuator functionality. The formability of the compound is achieved using a viscous adhesive, surrounding the piezomodule during the forming operation. The low viscosity of the adhesive allows a relative movement between the piezomodule and the sheet metals and drastically reduces the transfer of critical strains to the piezomodule. Curing of adhesive takes place after the forming operation. To improve the efficiency of the process chain an advanced adhesive system with robust application properties has to be used. Furthermore, the productivity of several fabrication steps and their sequence in the process chain have to be verified and improved. The paper presents the process chain designed for automated production of formable sandwich sheets with integrated piezomodules, including the production steps for the fabrication of the semi-finished part as well as the forming operation. Aiming on a good formability during the shaping operation and on a stiff connection between the piezomodule and the sheet metal in the finished sandwich part, one focus is set on the adhesive properties required during the different process steps.