Fraunhofer Adaptronics Alliance
The wire offers a wide range of applications, requires little space and is cost-effective. The material is also characterized by a very high energy density. Elongations of up to 8% of the wire length are possible, resulting in displacements.
Modern manufacturing processes are characterized by an increasing degree of complexity. Smallest deviations of individual parameters can lead to the destablization of the whole process.
Conventional satellite design usually separates between structural and non-structural functions. The primary structure mainly supports mechanical loads and provides attachement points to the subsystems. These are developed and tested separately and integrated at the final stage of the assembly process. Such separation typically not only increases mass and installation volume but also times and cots for the production and the launch of the spacecraft.
With regard to the operation of electronic systems, batteries are indispensable for the provision of the supply energy. However, due to the limited life, not only increased costs, but also higher environmental loads are caused by the replacement or disposal of used batteries.
Digital Twins are numerical models approximating the physical world that process real and virtual infor-mation simultaneously. The combination of calculated and measured signals enables a more detailed and extended analysis of technical systems. Parametric and real-time Digital Twins also provide other interesting application scenarios. The models can be fast and efficiently validated or can be used for condition monitoring or as virtual sensors.
Lightweight structures compared to conventional structures are more prone to induced vibration due to their low mass and low damping. The Fraunhofer Institute for Structural Durability and System Reliability (LBF) demonstrate an application of semi-active, damping embedded structure with suitable sensors and piezo-actuators by using a smart fiber composite.
Additionally, the embedded sensors can be used for wear and stress monitoring of the component.
In conveyor applications, toothed belts often drive moving machine parts that require energy for motors, sensors and actuators. A cable trailing cable is required to supply these energy consumers. A system was developed at the Fraunhofer IWU that enables contactless energy transfer to a timing belt without cable trailing cable.
By using rotating ultrasonic vibrational systems to excite tools, a reduction in process costs and an increase in machining quality is achieved. The systems can be used in any machine tool. They are also equipped with integrated amplitude control.
Machining of composites, certainly for CFRP, as well as machining of hard materials (break disks made of C/C-SiC) are combined with massive friction and ool wear. These materials can be machined with low productivity or having high costs. Some materials can only be grinded.
Innovation :
High performance machining with vibrational assistance by means of tool excitation with ultrasonic vibration.
Conventional construction solutions that enable deformations or changes in stiffness of a structure consist of a variety of components and have isadvantages concerning their heavy weight. Through functionally integrated lightweight construction it is conceivable to reduce system complexity and mass. By integrating shape-memory actuators into fiber-reinforced polymers, it is possible to realize lightweight structures with variable geometry and stiffness.
Fiber reinforced plastics and polymeres are highly elastic. In order to measure strain of parts made of these, strain sensors have to be highly elastic too. Such sensors certainly for cyclic loading conditions with high amplitudes are not available. Metallic resistance strain gauges have a limited cyclic strain capability.
Wear-resistant thin film sensor systems are playing an ever greater role in the most varied applications, especially in the field of real-time acquisition of process data. For this reason the aim of the EU‘s »S ensorized Future« project is, among other things, to create a sensorized thin-film system which simultaneously during the plastic injection molding process picks up both the force and also the temperature distribution at the surface of the mold. For this purpose individual sensor modules have been developed at the Fraunhofer IST which can be fitted very precisely in to the mold.
The fourth industrial revolution – Industry 4.0 – can only succeed when not only the data processing is set value on but also the sensor technology which is responsible for the measurement data. In recent years industry has increasingly felt the need for a sensor system which is used directly on component surfaces in contact with the workpiece so as to be able to capture measurement data locally even during the process. A multifunctional thin film system is therefore being developed at the Fraunhofer IST for the local measurement of pressure and temperature distribution over the surface of deep-drawing dies. It is a multilayer system with which not only is local measurement of force or pressure on surfaces with complex shapes possible but also local temperature measurement at different parts of the component. The system also has a high wear resistance.
Within the Fraunhofer System Research for E-Mobility (FSEM II) project, 16 different Fraunhofer institutes are jointly drafting solutions for the future of e-mobility. The three Fraunhofer institutes IISB, IFAM and LBF are pooling their expertise in the “Drivetrain/Chassis” cluster for an innovative air-cooled electrified drivetrain with adaptive chassis damper.
The development of lightweight structures, which take account of comfort, precision or reliability, is a complex procedure – no matter what the commercial field. In order to save time and prototype costs, the development process is often extended through numerical simulation. Fraunhofer institute LBF developed the Mechanical Simulation Toolbox to help design passive, semi-active and active systems. Moreover, the toolbox – based on MATLAB® benefits from analyzing tools to measure the obtained vibration reduction. Apart from sales and training, we support our customers with automating their IT procedures and the development of customized toolboxes.
The reduction of unwanted noise and vibrations in vehicles is often a design requirement related to the comfort of passengers. However, classical countermeasures are usually associated with additional weight. In an automotive suspension, the control arm is a major transfer path for small vibrations induced e.g. by the road roughness, resulting in decreased NVH comfort inside the car. The goal of this research project was to develop a smart control arm that is lightweight, that meets the stiffness requirements and that presents enhanced structural damping without excessive additional weight. It has been especially designed with lightweight composite materials and with integrated piezoceramic transducers capable of absorbing mechanical vibrations through a semi-active shunt damping.
Rolling bearings do require a negative clearance or preload depending on bearing type, required speed, accuracy and rigidity. The preload determines decisively the performance characteristics such as durability, noise, load capacity, compensation of wear and setting operations of the bearing. As a result, the selection of the preset preload is usually a compromise. And for this reason it would be desirable, if there was an available way to control the preload during operation. By means of an actuator to influence the preload, it is possible to increase the service life of the component and to compensate temperature influences. In addition, the machining accuracy can be increased and a significant contribution to resource efficiency and availability of the machine tool can be achieved.
Reinforced and plain polymers are highly elastic. In order to measure strain of parts made of these, strain sensors have to be highly elastic too. Such sensors certainly for cyclic loading conditions with high amplitudes are not available. Metallic resistance strain gauges have a limited cyclic strain capability and an elastic limit below one percent strain. Fiber Bragg grating sensors are highly elastic. But the electronic measuring equipment for this optical sensors is complex, expensive and voluminous. Therefore it is not suitable for mobile applications. Carbon fibres can be used as strain sensors in composites. Their gauge factor is comparably low and measurements are highly temperature dependent. An alternative strain sensor with high elasticity is therefore needed.
The force distribution in forming tools influences the deep drawing process signi-ficantly. This force distribution depends on different factors, e.g. the tool geometry, stiffness in the machine/tool-system and the control of machines with multiple axis. For the reduction of the try-out process of forming tools as well as the adaption the force distribution by means of different actuator systems a metrological detection of the distribution is necessary. To simplify the handling and to increase the flexibility of application specific demands regarding the construction and the setup of the measuring system have to be considered.
The number of offshore wind turbines is continuously increasing and even doubled in German sea areas during the last year. Especially foundation structures are heavily loaded by wind and waves influences. This can lead to local weld failure. Since the application of conventional testing techniques in the offshore sector is limited, it is necessary to develop an appropriate permanent monitoring method.
Piezoelectric transducers based on piezoceramic-polymer-composites are predominantly used as sensors, actuators, ultrasonic transducers, or energy harvesters in smart structures, medical science and non-destructive testing. In the sense of cost- and performance-effective production piezoceramic components as well as resulting piezoelectric composites have to be adjusted to application needs.
The sequential integration of piezoceramic elements into electronic, fluidic, and optical systems by assembling or joining techniques is limited if patterned structures or cost-efficient production are demanded.
Cumulino is an active positioning cushion to cure and prevent infancy skull asymmetries.
Since supine sleeping position is recommended for infants it gets more likely to skull deformations. These deformities can be caused by positional anomalies in utero or postnatally. For example 19.7% of newborns in the fourth month are affected.
Nearly 40 percent of the total energy consumption in Germany is caused by the housing sector. Heating, cooling and ventilation of houses, office buildings and public buildings is expensive. True energy squanderer are office buildings with large-area glass facades. In summertime they turn into greenhouses. In winter, the heating demand is growing rapidly due to insufficient insulation of glass surfaces.
To reduce energy consumption, researchers of the Fraunhofer Institute for Machine Tools and Forming Technology IWU in Dresden are developing in cooperation with the Department of Textile and Surface of the Berlin Weissensee School of Art wall components that react autonomously to sunlight and the heat thereof.
The force distribution in forming tools influences the deep drawing process significantly. This force distribution depends on different factors, e.g. the tool geometry, stiffness in the machine/tool-system and the control of machines with multiple axis. For the reduction of the try-out process of forming tools as well as the adaption of the force distribution by means of different actuator systems a metrological detection of the distribution is necessary. To simplify the handling and to increase the flexibility of application specific demands regarding the construction and the setup of the measuring system have to be considered.
LEAF serves as a communication tool for the domestic flora. Attached to the flower pot LEAF senses the growing conditions of the plant. Temperature, humidity and light conditions are detected and evaluated by the integrated electronics.
Symbolized by laves, the resulting information can be visualized. The smart pointers move and deform analogous to the needs of the plants for light, water and temperature. The deformation is caused by a structurally integrated actuator made of shape memory material.
Modern homes and office buildings are often equipped with forced ventilation and air conditioning systems. From an acoustical point of view this may cause problems due to disturbing noise emissions and unwanted sound transmissions from adjacent rooms and corridors. Compact active noise control (ANC) modules based on the principle of active anti-sound can be used to reduce acoustic disturbance, improve acoustical comfort and to protect privacy. In this Project the Fraunhofer LBF explores ANC concepts and develops practical compact active noise control modules, integrated with adequate passive acoustic measures; with the aim to increase the application readiness of this innovative technology.
Fraunhofer LBF developed an energy efficient magnetorheological damper. An adjustable field generated by a physically moveable permanent magnet is superposed by a second field generated by a solenoid coil.
Fraunhofer Adaptronics Alliance