Malfunctions and failures within the adaption process are harmful for the overall load-bearing structure or compromise functioning for the user and have to be avoided or rather detected in time. Therefore, if a failure occurs it may not have fatal consequences.
For this reason project B03 examines uncertainties, disturbances, faults and failure possibilities. An integrated monitoring and fault detection informs about the occurrence of faults. A subsequent fault diagnosis allows conclusions about the fault location, which is used for their isolation and detection at an early stage. To design the system less susceptible to interferences and more robust against disturbances, the disturbances are estimated. When it comes to a failure or a failure is probable, an adaptive, hybrid, cross-domain and cross-level fail-safe-concept minimizes the impact of damage. It uses active and passive fail-safe-elements within the adaptation regarding the expectable situation to decrease the impact of failure and guarantee a safe state for a certain time.
Summarized this yields to the following essential questions:
- How can elements and frameworks of adaptive load-bearing structures be reliability-oriented modelled and analyzed?
- Which fault-critical situations exist and which methods will lead to an adaptive, hybrid, cross-domain and cross-level fail-safe-concept?
- Which possibilities exist to design fail-safe elements and frameworks?
- Which interactions exist between the hybrid elements of the fail-safe-concept and how can they be connected in an optimal way?
- How can the status of the framework be monitored and which failure reactions are necessary to avoid fatal faults?
- How does the fail-safe-system and the overall adaptive system interact?
- How can disturbances and faults be modelled and estimated?
- What are relevant measurement signals for the detection of faults?
- Which methods are suitable for fault detection and diagnosis in adaptive structures?
Basic objectives for the fail-safe-concept are modeling and estimation of faults and disturbances in distributed systems. Both disturbance and fault models have to be developed for the elements and frameworks of adaptive load-bearing structures.
Different methods for disturbance and load estimation are developed and criteria for the differentiation between load and fault scenarios are derived. The reliability and accuracy of the disturbance and load estimation is evaluated and classified.
A special challenge is the modeling of failures in distributed systems. By a various staged, adaptive failure reaction the operational state should be sustainable. A major part of the safety concept is the particular combination of active and passive safety elements, accessing the adaption process static as well as dynamic and level the failure reaction.
The results of the fault diagnosis is passed to the projects B02 and B04 for reconfiguring the observer and controller. C02 is provided with reliability requirements for choosing an actuator concept and later optimizing it regarding reliability. For a reliable power supply of the electro active polymers the fail-safe-concept is handed to C03.
- Prof. Dr.-Ing. Bernd Bertsche, Institute of Machine Components
- Prof. Dr.-Ing. Cristina Tarín, Institute for System Dynamics