This propoject will investigate the fundamental properties and applications of novel arrays of nonlinear actuators for the nondestructive evaluation (NDE) and structural health monitoring (SHM) of civil structures and materials. The investigators will also explore the ability to use the nonlinear actuators for focusing and harvesting elastic energy, and for imaging bulk materials. The arrays of nonlinear actuators included in this study can generate highly nonlinear solitary waves (HNSWs), which are compact non-dispersive stress waves with a finite spatial dimension. The spatial dimension of these pulses is independent of the wave amplitude and dependent only on the nonlinear material's geometry. HNSWs hold promise to improve current NDE/SHM devices because of their ability to support non-oscillatory, high amplitude signals that rely exclusively on mechanical excitations.

On a fundamental level, the investigators aim at understanding the behavior of arrays of highly nonlinear actuators adjacent to different neighboring solid media. In particular, they will: (i) study the ability to focus nonlinear waves as a function of the properties of the adjacent media, (ii) design and implement methods to improve transmission of the signal across the interface between the actuators and the adjacent media; (iii) determine the limitations of signal power and the degradation of performance due to failure of the highly nonlinear actuators. From a purely applied perspective, the project will be devoted to the application of HNSWs for the NDE/SHM of structural materials.

Besides the impact to the nonlinear dynamics scientific community, the proposed research will have strategic importance to a broad range of engineering applications. The NDE/SHM component of this research enables to increase the safety of existing civil and aerospace structures. The ability to harvest focused elastic energy has the potential to create new, sustainable means to power small electronic devices and sensors. This research outcomes will enable the development of novel transducers arrays for acoustic imaging, the successful outcome of our research could impact the biomedical imaging community.

Some of the research outcomes and experiments will be integrated into the investigators' teaching portfolio and into outreach activities. This research will provide multidisciplinary training for all participating students. As the submission of at least one patent application is forecast, potential marketing opportunities will be explored. Finally, the research results will be broadly disseminated through the submission of journal articles and through the presentation at conferences of international audience.

Project Start
Project End
Budget Start
2012-09-15
Budget End
2015-12-31
Support Year
Fiscal Year
2012
Total Cost
$260,000
Indirect Cost
Name
California Institute of Technology
Department
Type
DUNS #
City
Pasadena
State
CA
Country
United States
Zip Code
91125