@misc{JirasekSchauerBleicher, author = {Jirasek, Robert and Schauer, Thomas and Bleicher, Achim}, title = {Active Vibration Control of a Convertible Structure Based on a Polytopic LPV Model Representation}, series = {IFAC-PapersOnLine}, volume = {53}, journal = {IFAC-PapersOnLine}, number = {2}, issn = {2405-8963}, doi = {10.1016/j.ifacol.2020.12.1590}, pages = {8389 -- 8394}, abstract = {This paper deals with modeling and control of lightweight convertible structures for the application in civil and structural engineering. Such structures are prone to vibrations due to their lightweight design. In addition, they exhibit transformation state dependent dynamic behavior. In order to guarantee a reliable operation, the use of active vibration control (AVC) is an effective means. For the example of a simplified convertible structure, modeling is demonstrated using the linear parameter-varying (LPV) framework. Based on local linear time-invariant (LTI) models, derived from a finite element model of the convertible structure, a polytopic LPV model is established. This LPV model is then utilized to design a polytopic LPV output-feedback controller for AVC during the structure's transformation. The effectiveness of the designed controller is validated in simulation.}, language = {en} } @misc{ZhangSchauerWernickeetal., author = {Zhang, Yangwen and Schauer, Thomas and Wernicke, Laurenz and Wulff, Wulf and Bleicher, Achim}, title = {Facade-Integrated Semi-Active Vibration Control for Wind-Excited Super-Slender Tall Buildings}, series = {IFAC-PapersOnLine - 21th IFAC World Congress}, volume = {53}, journal = {IFAC-PapersOnLine - 21th IFAC World Congress}, number = {2}, address = {Berlin}, issn = {2405-8963}, doi = {10.1016/j.ifacol.2020.12.1585}, pages = {8395 -- 8400}, abstract = {Nowadays, skyscrapers are getting higher and more slender due to inner-city concentration, which makes the structure more susceptible to dynamic excitations. The design of super-slender skyscrapers is governed primarily by wind excitation. A traditional Tuned Mass Damper (TMD) has been installed in many skyscrapers to mitigate wind-induced vibrations, which has been proven to be very reliable. However, it needs large additional mass and huge installation space near the top of the building, which makes TMD not optimal for superslender skyscrapers. In this paper, a semi-active distributed-Multiple Tuned Facade Damper (d-MTFD) using movable facade elements as damping mass is investigated. The facade elements at the upper stories of the building are parallel movable to the primary structure. Electrical Machines (EM) as variable damper are integrated in their connections to realize semi-active vibration control, which makes the system more effective and robust. For real application, a practical design criterion is that the relative displacement of the facade elements cannot be too large, otherwise it makes the occupants feel uncomfortable. Therefore, multi-objective Genetic Algorithm (GA)-optimized on-off groundhook semi-active control is applied, where two control objectives are optimized. One control objective is to minimize the peak top floor acceleration and the other control objective is to minimize the maximum peak relative displacement of all the facade elements. As a result, a Pareto Front shows that better vibration suppression performance and smaller facade relative displacement can be achieved using the multi-objective optimized controller.}, language = {en} } @misc{ZhangSchauerWernickeetal., author = {Zhang, Yangwen and Schauer, Thomas and Wernicke, Laurenz and Vrontos, Apostolos and Engelmann, Michael and Wulff, Wulf and Bleicher, Achim}, title = {Design of Moveable Facade Elements for Energy Harvesting and Vibration Control of Super Slender Tall Buildings under Wind Excitation}, series = {POWERSKIN Conference Proceedings, M{\"u}nchen}, journal = {POWERSKIN Conference Proceedings, M{\"u}nchen}, publisher = {TU Delft Open}, address = {MUNICH}, isbn = {978-94-6366-406-6}, pages = {327 -- 338}, abstract = {Tall buildings are increasingly built worldwide due to significant economic benefits in dense urban land use. But super-slender tall buildings are very susceptible to wind excitation. Tuned Mass Damper (TMD) and distributed-Multiple Tuned Mass Damper (d-MTMD) have been widely investigated passively and actively and proven to be e cient solutions to mitigate the structure vibration. However, they both need additional mass and huge installation space near the top of the building. In this contribution, a new semi-active distributed-Multiple Tuned Fa{\c{c}}ade Damper (d-MTFD) is investigated that employs the mass of the outer skin of a Double-Skin Fa{\c{c}}ade (DSF) as damping mass. The outer skin of DSF at the upper storeys of the building are parallel moveable to the inner skin fixed on the primary structure. A design criterion besides the damping of the primary structure vibration is that the relative displacement of the outer skin with respect to the inner skin fixed on the primary structure should not be too large. Otherwise, it makes the occupants feel uncomfortable and imposes too high constructional demands. Therefore, on-o ground-hook control is investigated, where the two control objectives are optimized using genetic algorithms. One control objective is to minimize the peak top floor acceleration, and the other control objective is to reduce the maximum peak relative displacement of all the moveable outer skins. This multi-objective optimization results in a Pareto Front, which allows choosing controller settings that yield a good trade-o between both objectives. The approach has been first validated in a simulation with a 306 m benchmark building for a wind speed of 13,5 m/s at 10 m above ground level with a return period of 10 years. Acceptable peak top floor accelerations for hotel usage and a maximal displacement between the primary structure and the moveable outer skin less than ± 0.5 m could be achieved despite the presence of rolling friction. The variable damping coe cients for the on-o ground-hook control can be realized by means of a stepper motor in each moveable DSF element which acts as a generator using customized power electronics for energy harvesting. An open research question is if the harvested energy will be su cient for enabling a self-sustainable operation of the embedded control system and power electronics. Further validations will be carried out in Hardware-in-the-Loop (HiL) simulations in which a currently built prototype of one moveable DSF element will be physically connected to the simulation of the benchmark building.}, language = {en} } @misc{BleicherSchauerJiraseketal., author = {Bleicher, Achim and Schauer, Thomas and Jirasek, Robert and H{\"o}ltke, Tim and Zhang, Yangwen and Marker, Paul and Wulff, Wulf and Manfrecola, Johannes and Schmidt, Therese}, title = {Hybride Konstruktionen an der BTU Cottbus-Senftenberg}, series = {Bautechnik}, volume = {98}, journal = {Bautechnik}, number = {12}, issn = {1437-0999}, doi = {10.1002/bate.202100056}, pages = {907 -- 920}, abstract = {Die angestrebten Ziele einer Ressourcen- und Klimaneutralit{\"a}t erfordern ein radikaleres Umdenken der Bauschaffenden, das mit einer noch viel st{\"a}rkeren Sensibilisierung der Auftraggeber f{\"u}r die Auswirkungen des Material- und Energieverbrauchs im Bausektor verbunden ist. Ein Ansatz, um diese Ziele zu erreichen, sind hybride Konstruktionen, in denen unterschiedliche Materialien, Elemente, Funktionen und Technologien auf mehreren Konstruktionsebenen ressourcen- und energieeffizient kombiniert sowie im Fall eines R{\"u}ckbaus sortenrein rezykliert werden. Dieser anspruchsvolle Ansatz ist von Beginn an erkl{\"a}rtes Ziel des Lehrstuhls Hybride Konstruktionen - Massivbau an der BTU Cottbus-Senftenberg und zieht sich durch alle Lehr- und Forschungsaktivit{\"a}ten. Mit ausgew{\"a}hlten Forschungsprojekten werden Motivation und Methoden hybrider Konstruktionen sowie deren Potenzial f{\"u}r ressourcen- und klimaneutrale Konstruktionen anhand von Prototypen aufgezeigt. Hierbei steht neben der {\"o}kologischen Weiterentwicklung klassischer hybrider Konstruktionen aus nachwachsenden und rezyklierten Rohstoffen, bspw. Holz und Recyclingbeton, auch die Entwicklung aktiver hybrider Konstruktionen im Fokus. Die gezielte Integration von aktiven Technologien wie Sensorik, Aktuatorik und Regelungstechnik erm{\"o}glicht multifunktionale Konstruktionen, einen hohen Nutzungskomfort, einen geringeren Rohstoffverbrauch bis hin zur Energiegewinnung aus dynamischen Einwirkungen.}, language = {de} } @misc{ZhangSchauerBleicher, author = {Zhang, Yangwen and Schauer, Thomas and Bleicher, Achim}, title = {Optimized passive/semi-active vibration control using distributed-multiple tuned facade damping system in tall buildings}, series = {Journal of Building Engineering}, volume = {52}, journal = {Journal of Building Engineering}, issn = {2352-7102}, doi = {10.1016/j.jobe.2022.104416}, pages = {104416}, abstract = {To reduce wind-induced vibrations, Tuned Mass Dampers (TMD) are widely used in high-rise buildings. However, traditional TMD system requires large additional damping mass and huge installation space at the top floors of the building. In this paper, a novel distributed-Multiple Tuned Facade Damping (d-MTFD) system is investigated. This system employs the outer skin mass of the Double-Skin Facade (DSF) as the damping mass. In the upper stories, the DSF's outer skin, mounted on a guide rail system, is designed to be parallel moveable. The passive/semi-active d-MTFD system, which is assumed to be installed on a 76-story benchmark building under across-wind excitation, is optimized using multi-objective Genetic Algorithms (GA) for two defined objectives: minimizing the peak top floor acceleration and controlling the maximum peak relative displacement of all the moveable DSF's outer skins. On-off groundhook control and displacement-reducing bang-bang control are used as semi-active control strategies. The rolling friction caused by the guide rail system has a considerable impact on the optimization results. These results are presented in the form of Pareto fronts. Optimized parameters can be selected to yield a good trade-off between both objectives. The optimized passive/semi-active d-MTFD systems can highly improve the structural response. Compared with the optimized passive d-MTFD system, the use of semi-active control can reduce the vibration of the DSF's outer skin significantly. Comparing the selected optimized cases with similar peak top floor acceleration, the peak top floor facade relative displacement using displacement-reducing bang-bang control decreases 58.3\%, and the Root Mean Square (RMS) value decreases 61.4\%.}, language = {en} } @misc{ZhangWulffWernickeetal., author = {Zhang, Yangwen and Wulff, Wulf and Wernicke, Laurenz and Engelmann, Michael and Schauer, Thomas and Bleicher, Achim}, title = {Moveable Facade Elements for Sustainable High-rise Buildings}, series = {IABSE Congress Nanjing 2022 - Bridges and Structures: Connection, Integration and Harmonisation}, journal = {IABSE Congress Nanjing 2022 - Bridges and Structures: Connection, Integration and Harmonisation}, address = {Nanjing, China}, isbn = {978-3-85748-184-0}, doi = {10.2749/nanjing.2022.1046}, pages = {1046 -- 1054}, abstract = {This paper presents a sustainable semi-active distributed-Multiple Tuned Facade Damping (d-MTFD) system that utilizes the existing mass of the Double-Skin Facade's outer skin as damping mass to mitigate structural vibrations caused by wind excitation. Based on this concept, a prototype with one full-scale parallel moveable facade element has been developed, built, and validated. A stepper motor working together with its connected energy harvesting circuit is innovatively applied as an adjustable electrical damper and simultaneously as an energy harvester. Its feasibility has been proven through experiments using Hardware-in-the-Loop (HiL) simulations. An energy harvesting efficiency of 75\% was achieved by using a two-stage power converter as the energy harvesting circuit. The self-sufficiency of the semi-active d-MTFD system was achieved.}, language = {en} } @misc{ZhangWulffWernickeetal., author = {Zhang, Yangwen and Wulff, Wulf and Wernicke, Laurenz and Engelmann, Michael and Schauer, Thomas and Bleicher, Achim}, title = {Experimental identification and verification of a moveable facade element for energy harvesting and vibration control}, series = {Journal of Building Engineering}, volume = {65}, journal = {Journal of Building Engineering}, issn = {2352-7102}, doi = {10.1016/j.jobe.2022.105712}, abstract = {The distributed-Multiple Tuned Facade Damping (d-MTFD) system was proposed to effectively reduce wind-induced vibrations of high-rise buildings by using the parallel moveable outer skin of the Double-Skin Facade (DSF) as damping mass. A full-scale prototype with a moveable (kinetic) DSF element has been built for first experimental tests using Hardware-in-the-Loop (HiL) simulations. The parallel moveability of the DSF's outer skin is achieved by mounting it on a smooth-running guide rail system. A stepper motor is applied as an adjustable electrical damper and simultaneously serves as an energy harvester. By using grey-box system identification, all the parameters of the prototype can be accurately estimated. For example, a low equivalent friction ratio of 0.0022 was estimated. The identified model achieved high fitness values (80\% to 91\%) compared to the measured data, providing the basis for the reliability of the experimental tests using HiL. The prototype is the hardware part of the HiL simulations, which is connected to the simulation part, namely, a 76-story, 306 m high benchmark building assumed to be installed with the d-MTFD system. The feasibility of using a stepper motor as an adjustable electrical damper for semi-active control has been successfully validated based on the HiL simulations. By using semi-active control, the relative displacement of the DSF's outer skin can be significantly reduced by about 35\% compared with using passive control. Energy harvesting performance has also been investigated. The average energy harvesting efficiency of the power electronics was experimentally determined as approximately 75\%. With consideration of all the parasitic damping in the connection, the average energy harvesting efficiency was about 50\%. For tests under across-wind excitation with a return period of 10 years, the self-sufficient operation of the semi-active d-MTFD system was proven to be achievable based on the prototype results. The average harvested power of the whole benchmark building (with 1000 moveable facade elements) can be predicted as 1.3 kW.}, language = {en} } @misc{JirasekSchauerBleicher, author = {Jirasek, Robert and Schauer, Thomas and Bleicher, Achim}, title = {Linear parameter-varying output-feedback for active vibration control of an elastic kinetic roof structure with experimental validation}, series = {Engineering Structures}, volume = {307}, journal = {Engineering Structures}, issn = {0141-0296}, doi = {10.1016/j.engstruct.2024.117887}, pages = {1 -- 12}, abstract = {Elastic kinetics are an approach to design transformable lightweight structures with a stable transformation process. The transformation is realized through elastic bending of structural members by exploiting the compliant material behavior. This lightweight and flexible design comes at the cost of increased sensitivity to static and dynamic disturbances. However, most of the current research focuses on the principles of elastic kinetic transformation instead of effective disturbance mitigation. This work focuses on dynamic disturbance mitigation for such transformable lightweight structures using active control. Modeling and controller synthesis are performed in the linear parameter-varying (LPV) framework, since the dynamics of elastic kinetic structures are transformation-state dependent due to geometric nonlinearities. Based on an LPV model in a grid-based representation, an LPV output-feedback control can be designed and synthesized via a gridding approach. This methodology is experimentally tested and validated for the example of an active hybrid roof structure prototype.}, language = {en} } @techreport{SchauerBleicherZhangetal., author = {Schauer, Thomas and Bleicher, Achim and Zhang, Yangwen and Wulff, Wulf and Wernicke, Laurenz}, title = {Schwingungsd{\"a}mpfung und Energiegewinnung mit beweglichen Doppelfassaden: Entwurf Optimierung und Validierung eines autarken verteilten semiaktiven Systems zur Reduktion Wind-induzierter Schwingungen bei schlanken Hochh{\"a}usern}, volume = {08/2022}, address = {Bonn}, issn = {1868-0097}, url = {http://nbn-resolving.de/urn:nbn:de:101:1-2022112808245531150998}, pages = {98}, abstract = {Weltweit werden immer mehr „superschlanke" Hochh{\"a}user gebaut, da sie bei einer dichten st{\"a}dtischen Fl{\"a}chennutzung erhebliche wirtschaftliche Vorteile bieten. Jedoch sind sie sehr anf{\"a}llig f{\"u}r Windanregungen. Schwingungstilger sind passiv als auch aktiv Stand der Technik und haben sich als effiziente L{\"o}sungen zur D{\"a}mpfung Wind-induzierter Strukturschwingungen erwiesen. Dieser Ansatz ben{\"o}tigt jedoch zus{\"a}tzliche Masse und einen großen Bauraum in den begehrten obersten Etagen. In diesem Forschungsprojekt wurde ein neuer semiaktiver und verteilter Fassadend{\"a}mpfer untersucht, der die Masse der Außenhaut einer Doppelfassade im Sinne der Ressourceneffizienz als D{\"a}mpfungsmasse nutzt. F{\"u}r die Realisierung einer zeitlich ver{\"a}nderlichen D{\"a}mpfung wurde ein mechatronischer Schwingungsd{\"a}mpfer inklusive Energie-Harvester entwickelt, der Energie in einer Batterie speichert. Zur Validierung der Konzepte und zum Nachweis des autarken Betriebs des geregelten D{\"a}mpfungssystems wurde in Zusammenarbeit mit der Josef Gartner GmbH ein bewegliches Doppelfassadenelement als Prototyp realisiert und auf einem Versuchsstand installiert. Dies erlaubt die Durchf{\"u}hrung von Hardware-in-the-Loop Simulationen, bei denen ein gesamtes Geb{\"a}ude simuliert wird und ein einzelnes Fassadenelement als Hardware physisch aktiv ist und sein Verhalten untersucht werden kann. Die Machbarkeit einer autarken semiaktiven D{\"a}mpfung mit parallel beweglichen Prallscheiben an Doppelfassaden konnte somit erfolgreich demonstriert werden. Der Ansatz liefert einen Beitrag, den CO2-Fußabdruck eines Hochhauses zu reduzieren.}, language = {de} } @misc{ZhangWernickeWulffetal., author = {Zhang, Yangwen and Wernicke, Laurenz and Wulff, Wulf and Bleicher, Achim and Schauer, Thomas}, title = {Design and validation of a dual-functional damper based on a stepper motor for energy harvesting and vibration control}, series = {Mechanical Systems and Signal Processing}, volume = {200}, journal = {Mechanical Systems and Signal Processing}, number = {110568}, issn = {0888-3270}, doi = {10.1016/j.ymssp.2023.110568}, pages = {1 -- 19}, abstract = {Dampers are widely used to reduce undesired vibrations. In recent decades, they have been developed from the energy dissipation strategy to the energy harvesting strategy. Dual-functional dampers, which convert part of vibration energy into electrical energy, are intensively studied. DC motors are the most applied electromagnetic transducers in these studies. In this paper, two-phase stepper motors are applied as adjustable electrical dampers and energy harvesters. Dual-functional dampers using stepper motors inherently have higher damping density than those using DC motors, as stepper motors have more pole pairs than DC motors. The nonlinear theoretical electrical damping coefficient of two-phase stepper motors is derived and compared with that of DC motors. A dual two-stage Energy Harvesting Circuit (EHC) is proposed to realize the function of adjustable electrical damping through resistance emulation and the function of harvesting energy. A test bench is built to experimentally verify the adjustable electrical damping and energy harvesting performance of a selected two-phase hybrid stepper motor with the proposed dual two-stage energy harvesting circuit. The numerical solution from the identified model shows a high agreement with the experimental results. The energy harvesting efficiency in the electrical domain has reached about 85\%. This tested dual-functional damper using a stepper motor has been successfully integrated into a full-scale demonstrator of the distributed-Multiple Tuned Facade Damping (d-MTFD) system.}, language = {en} } @misc{JirasekSchauerSuetal., author = {Jirasek, Robert and Schauer, Thomas and Su, Di and Nagayama, Tomonori and Bleicher, Achim}, title = {Experimental linear parameter-varying model identification of an elastic kinetic roof structure}, series = {Engineering Structures}, volume = {297}, journal = {Engineering Structures}, issn = {0141-0296}, doi = {10.1016/j.engstruct.2023.116986}, pages = {1 -- 13}, abstract = {Elastic kinetic structures are a recent approach to design transformable lightweight structures. Their transformation is based on elastic bending, exploiting the compliant material behavior of the structural members. This enables transformable structures with a stable transformation process. However, due to their lightweight and flexible design, elastic kinetic structures are highly sensitive to static and dynamic disturbances. Moreover, such transformable structures exhibit a transformation state dependent dynamic behavior, due to geometric nonlinearities. Nevertheless, most of current research focuses on the principles of elastic kinetic transformation than on effective disturbance mitigation. The latter is usually designed based on low-order control-oriented models. This paper describes a system identification methodology, suitable to identify low-order models for the transformation state dependent dynamics of elastic kinetic structures. The system identification is carried out using a local approach in the linear parameter-varying (LPV) framework. For the identification of local linear time-invariant (LTI) models, the system realization using the information matrix (SRIM) method is applied. The collection of local LTI models is internally balanced using a balancing transformation, in order to represent the locally estimated models with respect to a common state-space basis. Via linear interpolation, an LPV system in grid-based representation is derived. This methodology is experimentally validated with data from an active hybrid roof structure prototype.}, language = {en} } @incollection{FreymannSchauerBleicher, author = {Freymann, Konrad and Schauer, Thomas and Bleicher, Achim}, title = {Adaptive Doppelfassade zur Schwingungskontrolle}, series = {Beyond Transparency}, booktitle = {Beyond Transparency}, editor = {GmbH, Messe D{\"u}sseldorf}, publisher = {Messe D{\"u}sseldorf GmbH}, address = {D{\"u}sseldorf}, pages = {26 -- 26}, language = {de} }