Subproject C3

Uncertainty in the assessment of structure-properties relations in active and adaptronic load-carrying systems

In subproject C3, the initial conditions in using an active system for stabilization purposes of thin columns, see subproject C2, have been assessed and represented with the SFB 805 process model by numerical and experimental methods.

First results match the aimed work package stated in the SFB 805 proposal for the first funding period for the reliability-based component selection and design. Appropriate experimental test strategies for active components were developed. Both work packages on evaluating active component properties degradation and uncertainty in the assessment of the overall system reliability were partially achieved. Besides using appropriate simulation methods and designing test rigs and test scenarios for components and system, experimental long term tests on piezoelectric stack actuators in the active column have been started to evaluate the time variant interaction between the actuator’s and the passive column’s dynamic behavior. These long term tests have not been finished within the first funding period due to the time consuming first examination about the current relation and its description between active and passive system components. Similarly, retrieving uncertainty ratios was not completely achieved.

Despite the delays the ending subproject C3 has set an important milestone in SFB 805 with the analysis, the cross-process description and the assessment of uncertainty in structure-properties relation in active load carrying systems using the SFB uncertainty and process models. The results of structure-property-relation between the piezoelectric stack actuator and the passive load carrying structure together with the results of the load and system state control study from the ending subproject C1 are the basis of the new subproject C7. The results of the former subprojects C3 and C1 are both relevant for structure health control methods to be develop in subproject C7 in the second funding period of the SFB.

[1] Ondoua, Serge; Platz, Roland; Nuffer, Jürgen; Hanselka, Holger (2010): Uncertainties in Active Stabilization of Buckling Columns by Means of Piezoelectric Materials. In: 21st International Conference on Adaptive Structures and Technologies 2010 (ICAST 2010), October 4 – 6. ICAST International Conference on Adaptive Structures and Technologies. University Park, Pennsylvania, USA: Curran.

[2] Platz, Roland; Ondoua, Serge; Habermehl, Kai; Bedarff, Thomas; Hauer, Thomas; Schmitt, Sebastian; Hanselka, Holger (2010): Approach to validate the influences of uncertainties in manufacturing on using load-carrying structures. In: P. Sas und B. Bergen (Hg.): Proceedings of ISMA 2010. International Conference on Noise and Vibration Engineering including USD2010. Leuven/Belgium, September 20-22. ISMA Advance Conference Programme; Katholieke Universiteit Leuven; International Conference on Noise and Vibration Engineering; ISMA; USD; International Conference on Uncertainty in Structural Dynamics; Leuven Conference on Noise and Vibration Engineering. Heverlee, S. 5319–5334.

[3] Koenen, Jan F.; Enss, Georg C.; Ondoua, Serge; Platz, Roland; Hanselka, Holger (2011): Evaluation and Control of Uncertainty in Using an Active Column System. In: AMM 104, S. 187–195. DOI: 10.4028/www.scientific.net/AMM.104.187.

[4] Ondoua, Serge; Platz, Roland; Hanselka, Holger (2011): A study on scatter in piezoelectric stackactuator characteristics as an uncertainty criterion in usage process of a load-carrying system. In: Proceedings of International Conference on Structural Engineering Dynamics ICEDyn 2011. Instituto Superior Técnico, Technical University of Lisbon. Tavira/Portugal.

[5] Ondoua, Serge; Platz, Roland; Nuffer, Jürgen; Hanselka, Holger (2011): A study of uncertainties in active load carrying systems due to scatter in specifications of piezoelectric actuators. In: Christophe Berenguer, Antoine Grall und Carlos Guedes Soares (Hg.): Advances in Safety, Reliability and Risk Management. ESREL 2011. Troyes/France: CRC Press, S. 2114–2120.

[6] Ondoua, Serge; Platz, Roland; Nuffer, Jürgen; Hanselka, Holger (2011): Unsicherheit in der Zuverlässigkeitsbewertung von aktiven Komponenten am Beispiel eines piezoelektrischen Stapelaktuators für eine aktive Knickstabilisierung. In: 25. Fachtagung Technische Zuverlässigkeit TTZ 2011, VDI-Berichte Nr. 2146. Leonberg, Germany, May 11 – 12. VDI Verein Deutscher Ingenieure, S. 145–158.

[7] Sprenger, André; Haydn, Michael; Ondoua, Serge; Mosch, Lucia; Anderl, Reiner (2012): Ontology-Based Information Model for the Exchange of Uncertainty in Load Carrying Structures. In: Applied Mechanics and Materials, Trans Tech Publications 104, S. 55–66. DOI: 10.4028/www.scientific.net/AMM.104.55.

[8] Ondoua, Serge; Platz, Roland; Hanselka, Holger (2013): Unsicherheit im Arbeitsdiagramm eines piezoelektrischen Aktuators für die aktive Stabilisierung von Stäben. In: 26. VDI-Fachtagung Technische Zuverlässigkeit 2013. Entwicklung und Betrieb zuverlässiger Produkte, VDI-Berichte Nr. 2210. Leonberg bei Stuttgart, April 23-24. VDI-Fachtagung Technische Zuverlässigkeit; VDI-Gesellschaft Produkt- und Prozessgestaltung. Leonberg/Germany: VDI-Verl. (VDI-Berichte, 2210), S. 261–270.

[9] Ondoua, Serge; Platz, Roland (2014): Numerical and experimental investigation of parameter uncertainty in the working diagram and in use of a single piezoelectric stack actuator to stabilize a slender beam column against buckling. In: A. Cunha, E. Caetano, P. Ribeiro und G. Müller (Hg.): Proceedings of the 9th International Conference on Structural Dynamics, EURODYN 2014. Porto/Portugal (2713-2719).

[10] Platz, Roland; Enss, Georg C.; Ondoua, Serge; Melz, Tobias (2014): Active stabilization of a slender beam-column under static axial loading and estimated uncertainty in actuator properties. In: Proceedings of the Second International Conference on Vulnerability and Risk Analysis and Management (ICVRAM) and the Sixth International Symposium on Uncertainty Modeling and Analysis (ISUMA). ASCE American Society of Civil Engineers. Liverpool, UK, S. 235–244.

Subproject Managers

Photo	Name	Contact
H	Prof. Dr.-Ing. Holger Hanselka
N	Dr. rer. nat. Jürgen Nuffer