Offenburg University of Applied Sciences
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Energy Supply from Renewable Energy Sources
No full textRenewable energy sources such as solar radiation, geothermal heat and ambient heat are available for energy conversion. With the help of special converters, these resources can be put to use. These include solar collectors, geothermal probes and chillers. They collect the energy and convert it to a temperature level high enough to be suitable for heat purposes. In the case of refrigeration machines, a distinction is made between electrically and thermally driven machines
Edge-based solution for battery energy management system: Investigating the integration capability into the building automation system
Get PDFRecently, photovoltaic (PV) with energy storage systems (ESS) have been widely adopted in buildings to overcome growing power demands and earn financial benefits. The overall energy cost can be optimized by combining a well-sized hybrid PV/ESS system with an efficient energy management system (EMS). Generally, EMS is implemented within the overall functions of the Building Automation System (BAS). However, due to its limited computing resources, BAS cannot handle complex algorithms that aim to optimize energy use in real-time under different operating conditions. Furthermore, islanding the building's local network to maximize the PV energy share represents a challenging task due to the potential technical risks. In this context, this article addresses an improved approach based on upgrading the BAS data analytics capability by means of an edge computing technology. The edge communicates with the BAS low-level controller using a serial communication protocol. Taking advantage of the high computing ability of the edge device, an optimization-based EMS of the PV/ESS hybrid system is implemented. Different testing scenarios have been carried out on a real prototype with different weather conditions, and the results show the implementation feasibility and technical performance of such advanced EMS for the management of building energy resources. It has also been proven to be feasible and advantageous to operate the local energy network in island mode while ensuring system safety. Additionally, an estimated energy saving improvement of 6.23 % has been achieved using optimization-based EMS compared to the classical rule-based EMS, with better ESS constraints fulfillment
PROFINET – Sichere Kommunikation im Produktionsbereich
No full textAn international study summarizes the threat situation in the OT environment under the heading "Growing security threats" [1]. According to this study, attacks on automation systems are likely to increase in the future. Accordingly, an automation system must be able to protect the integrity of the transmitted information in the future. This requirement is motivated, among other things, by the fact that the network-side isolation of industrial communication systems is no longer considered sufficient as the sole protective measure. This paper uses the example of PROFINET to show how the future requirements for a real-time communication protocol can be met and how they can be derived from the IEC 62443 standard
Additive laser excitation of giant nonlinear surface acoustic wave pulses
No full textThe technique of laser ultrasonics perfectly meets the need for noncontact, noninvasive, nondestructive mechanical probing of nanometer- to millimeter-size samples. However, this technique is limited to the excitation of low-amplitude strains, below the threshold for optical damage of the sample. In the context of strain engineering of materials, alternative optical techniques enabling the excitation of high-amplitude strains in a nondestructive optical regime are needed. We introduce here a nondestructive method for laser-shock wave generation based on additive superposition of multiple laser-excited strain waves. This technique enables strain generation up to mechanical failure of a sample at pump laser fluences below optical ablation or melting thresholds. We demonstrate the ability to generate nonlinear surface acoustic waves (SAWs) in Nb-SrTiO3 substrates, with associated strains in the percent range and pressures up to 3 GPa at 1 kHz repetition rate and close to 10 GPa for several hundred shocks. This study paves the way for the investigation of a host of high-strain SAW-induced phenomena, including phase transitions in conventional and quantum materials, plasticity and a myriad of material failure modes, chemistry and other effects in bulk samples, thin layers, and two-dimensional materials
3D Bin Picking with an innovative powder filled gripper and a torque controlled collaborative robot
No full textA new and innovative powder filled gripper concept will be introduced to a process to pick parts out of a box without the use of a camera system which guides the robot to the part. The gripper is a combination of an inflatable skin, and a powder inside. In the unjammed condition, the powder is soft and can adjust to the geometry of the part which will be handled. By applying a vacuum to the inflatable skin, the powder gets jammed and transforms to a solid shaped form in which the gripper was brought before applying the vacuum. This physical principle is used to pick parts. The flexible skin of the gripper adjusts to all kinds of shapes, and therefore, can be used to realize 3D bin picking. With the help of a force controlled robot, the gripper can be pushed with a consistent force on flexible positions depending of the filling level of the box. A Kuka LBR iiwa with joint torque sensors in all of its seven axis’ was used to achieve a constant contact pressure. This is the basic criteria to achieve a robust picking process
Adversarial Attacks on Object Detection Models in the Automotive Domain
No full textThe progress in machine learning has led to advanced deep neural networks. These networks are widely used in computer vision tasks and safety-critical applications. The automotive industry, in particular, has experienced a significant transformation with the integration of deep learning techniques and neural networks. This integration contributes to the realization of autonomous driving systems. Object detection is a crucial element in autonomous driving. It contributes to vehicular safety and operational efficiency. This technology allows vehicles to perceive and identify their surroundings. It detects objects like pedestrians, vehicles, road signs, and obstacles. Object detection has evolved from being a conceptual necessity to an integral part of advanced driver assistance systems (ADAS) and the foundation of autonomous driving technologies. These advancements enable vehicles to make real-time decisions based on their understanding of the environment, improving safety and driving experiences. However, the increasing reliance on deep neural networks for object detection and autonomous driving has brought attention to potential vulnerabilities within these systems. Recent research has highlighted the susceptibility of these systems to adversarial attacks. Adversarial attacks are well-designed inputs that exploit weaknesses in the deep learning models underlying object detection. Successful attacks can cause misclassifications and critical errors, posing a significant threat to the functionality and safety of autonomous vehicles. With the rapid development of object detection systems, the vulnerability to adversarial attacks has become a major concern. These attacks manipulate inputs to deceive the target system, significantly compromising the reliability and safety of autonomous vehicles. In this study, we focus on analyzing adversarial attacks on state-of-the-art object detection models. We create adversarial examples to test the models’ robustness. We also check if the attacks work on a different object detection model meant for similar tasks. Additionally, we extensively evaluate recent defense mechanisms to see how effective they are in protecting deep neural networks (DNNs) from adversarial attacks and provide a comprehensive overview of the most commonly used defense strategies against adversarial attacks, highlighting how they can be implemented practically in real-world situations
Industrie 4.0 : Der Weg zum digitalisierten Produktionsunternehmen
No full textDas Zeitalter der Digitalisierung ist geprägt durch einen erhöhten Wettbewerb. Eine Chance, bei steigendem Wettbewerb erfolgreich zu bestehen, liegt daher nur in der durchgängigen Digitalisierung von Produktionsunternehmen. Dieser Beitrag stellt eine dreistufige generische Unternehmensmodellplattform Industrie 4.0 vor, die die Durchgängigkeit von Prozessen vom Kunden bis zum Lieferanten auf allen Unternehmensebenen in den Mittelpunkt stellt. Die Schritte zur Bewertung und Gestaltung des Fortschritts auf dem Weg zum digitalisierten Produktionsunternehmen werden aufgezeigt
Krisenkommunikation und Online-Content – Content-Marketing als Teil des Dialogs
No full textKrisenkommunikation bezeichnet ein besonderes Kommunikationsszena¬rio, bei dem im Rahmen des Managements einer aktuellen, existenzbedro¬henden Krise durch den Dialog mit den entscheidenden internen und externen Stakeholdern die Bewältigung der Krise im Sinne des Krisenma¬nagements unterstützt oder überhaupt erst ermöglicht wird. Content-Mar¬keting kann hier einen wertvollen Beitrag leisten, wenn bereits der Bedarf der Zielgruppen an Information aktiviert und damit der Boden für einen Wertbeitrag des Contents geschaffen ist. Damit ist auch klar, dass Content-Marketing nur ein Instrument im Rahmen der Krisenkommunikation sein kann, das neben anderen Kommunikationsformaten der Werbung und Öf¬fentlichkeitsarbeit zum Einsatz kommt
Empirische Grenzwertermittlung der Klemmkraftwirkung in Stanzwerkzeugen zur nachhaltigen Steigerung der Prozesssicherheit
No full textIm Rahmen dieser Bachelorarbeit werden der Stanzprozess und seine Auswirkung auf die Prozesssicherheit genauer untersucht. Es haben sich in den vergangenen Jahren diverse Fehler im Zusammenhang mit dem Stanzprozess ergeben, weshalb speziell der Prozess des Lochstanzens genauer betrachtet werden soll. Der Fokus wird dabei auf die Fehlerursachen gelegt, mit dem Ziel diese zukünftig zu verhindern. Zu Beginn soll eine umfassende Recherche zum Thema des Stanzprozesses, der Stanzabfallklemmung und zur Ausgangssituation des Projekts erfolgen. Die daraus resultierenden fünf Klemmungsarten für Lochabfälle in der Werkzeugmatrize werden im Zuge einer empirischen Grenzwertermittlung als Versuchsreihe, in Bezug auf deren Klemmwirkung, miteinander verglichen und ausgewertet. Für die Durchführung einer solchen Versuchsreihe sind eine Konzeptionierung des Versuchsprinzips und eine konstruktive Umsetzung erforderlich. Der Prozess wird dabei vollständig nach internen Richtlinien ausgelegt. Die Auswertung der verschiedenen Klemmungen soll eine Aussage über die zu erwartende Klemmwirkung und deren Auswirkung auf die Prozesssicherheit ergeben