Funded by the European Union
WP 4 Smart sensors and actuators
A concept of a fast pneumatic valves based on a controlled snap-through effects of prestressed composites has been proposed. The intended application area is real-time control of air flow in adaptive pneumatic fenders used for protection of maritime installations and vessels.Conceptual work on piezotransducers for structural adaptation and fluid-less space applications.
Transducers for pipe SHM and their applicability for virtual isolation of pipe sections: Based on a prototyped system of propagation torsional wave generator and sensor, evolutions of the system shall integrate a wave directional principle. Since wave can be guided potentially two-ways, the generator shall imbed a system designed to emit waves in only one way. This will improve the post-processing protocol of virtual isolation of pipe sections and therefore the ability to identify the location of singularities and defects.
Transducers for vibro-acoustic control: in order to experimentally assess the adaptative strategy defined in WP3 for vibroacoustics, the design and the manufacturing of prototype electro-mechanical nodes will be done. These nodes will embark self-processing and self-sustainable components to make them deployed on large scale array of vibration sensors. Numerical studies and simulations of performance of shunted piezoelectric patches for wave propagation control have been performed.
Research and development of piezo-based sensors and actuators intended for the wide range of applications targeted in the project. Three main topics are identified: one is related to Structural Health Monitoring, SHM (WP1) applications and the other two are related to Adaptronics (WP3: Adaptive Impact Absorption, Active Control of Vibrations, Vibro-Accoutics, etc):
- For the SHM, piezo-patches are considered as the smart transducers able to emit and receive acoustic waves to detect defects. In particular, the use of piezo-composite patches is studied. Those patches feature a all-in-one array of independent patches, which allow to implement various detection strategies to enhance the damage detection. Since the piezo-composite patches are not yet available for testing, the work has concentrated on regular piezo-patches that are already available. Modeling and simulation of detection strategies have been carried out assuming the use of the standard patches. The short term objective is to glue standard patches on the structure and to make practical measurements. With those measurements it will be possible to confirm the simulation results, and to verify that the model is working properly. With the model validated, it will be possible to model and simulate the structure with the piezo-composite patches. In the meantime, the objective is to manufacture a new batch of piezo-composite patches so that they can be used later on for practical testing and demonstration.
- The first topic in Adaptronics is related to the Stepping Piezo Actuator (SPA), which is a long-stroke fine-resolution linear actuator. The idea is to investigate new control strategies of this actuator for applications in adaptronics, such as active isolation. A model of the actuator is currently being built, so that the proposed control strategies can be simulated. The short term objective is to propose a control strategy for being able to control the step size of the actuator to achieve a even higher resolution. This strategy will be first simulated, and then it will be tested in practice with a real actuator available at the moment. After validating the first control strategy, the objective is to propose advanced control strategies for active isolation taking advantage of the long stroke and enhanced resolution of the actuator. In the meantime, the final actuators and electronics will be manufactured for testing of the advanced strategies with the chosen actuators.
- The second topic in Adaptronics is the design of a fast and high-flow speed piezo-valve. The short term objective is to make a bibliography on the state of the art of such valves to propose a general topology for the valve. Then, a CFD model of the valve should be built in order to simulate it. This topic complements the first topic, and it will be addressed by the secondees when the first topic can not be pushed further.
