Design and development of a smart structural ambient vibration monitoring system | |
| Author | Marghoob, Muhammad Abdur Rahman |
| Call Number | AIT Thesis no.ST-25-24 |
| Subject(s) | Intelligent sensors--Design and construction Vibration--Data processing |
| Note | A thesis submitted in partial fulfillment of the requirements for the degree of Master of Engineering in Structural Engineering |
| Publisher | Asian Institute of Technology |
| Abstract | This thesis presents the design and development of a low-cost smart structural ambient vibration monitoring system that integrates open-hardware sensing, finite element modelling (FEM), and optimal sensor placement for structural health monitoring of civil structures. The sensing unit is based on a 4.5 Hz horizontal geophone combined with a custom low-noise analogue front-end, an ADS1263 32-bit delta-sigma ADC converter, and a Raspberry Pi 4B for data acquisition, on-board processing, and wireless communication. Hardware performance is validated through shake-table experiments against a commercial Raspberry Shake instrument, showing very close agreement in identified peak frequencies, with 0% deviation. Ambient vibration tests further demonstrate that the proposed sensor achieves root-mean square velocity noise levels of only a few micrometers per second in the 0.1-40 Hz band, confirming its suitability for low-amplitude structural monitoring.On the algorithmic side, a real-time sensor placement and re-optimization framework based on the Effective Independence (EFI) method is implemented. The EFI procedure uses the Fisher Information Matrix and is evaluated with entropy and condition number metrics when reference mode shapes are available. This framework is embedded in a 3D FEM and BIM interface, allowing users to visualize structural models, assign and update sensor locations, stream live data, and view mode shapes extracted using operational modal analysis. A feedback mechanism identifies poorly performing sensors, such as channels with low SNRs and recommends alternative locations using updated mode shapes and information metrics.Three numerical case studies, consisting of a simply supported beam and an irregular two dimensional, are used to verify the EFI implementation and the adaptive re-optimization logic. For the beam, MAC values above 0.97 are obtained between FEM and identified modes. The frame achieves similar values close to unity for three target modes. Experimental validation on a laboratory steel frame confirms that the combined hardware and software platform can reliably capture low-frequency ambient vibrations and maintain good observability of target modes through adaptive sensor configuration. Overall, the results indicate that the proposed smart ambient vibration monitoring system is a practical and cost-effective tool for real-time structural health monitoring and research applications. |
| Year | 2025 |
| Type | Thesis |
| School | School of Engineering and Technology |
| Department | Department of Civil and Infrastucture Engineering (DCIE) |
| Academic Program/FoS | Structural Engineering (STE) /Former Name = Structural Engineering and Construction (ST) |
| Chairperson(s) | Krishna, Chaitanya |
| Examination Committee(s) | Pennung Warnitchai;Punchet Thammarak;Panon Latcharote |
| Scholarship Donor(s) | Computers and Structures Inc. (CSI), USA;AIT Scholarship |
| Degree | Thesis (M. Eng.) - Asian Institute of Technology, 2025 |