Filippo Parrini

Bio: Filippo Parrini is an academic researcher from University of Florence. The author has contributed to research in topics: Radar & Ground-penetrating radar. The author has an hindex of 11, co-authored 31 publications receiving 604 citations.

High-speed CW step-frequency coherent radar for dynamic monitoring of civil engineering structures

Abstract: A high-speed coherent radar for dynamic testing of civil engineering structures is proposed. The radar operates a continuous-wave (CW) step-frequency in Ku-band, and the base-band signal is generated by direct digital synthesis. Vibration measurements carried out on a 200 m-long bridge forced by vehicular traffic are reported.

Static and dynamic testing of bridges through microwave interferometry

Abstract: A novel microwave sensor capable of remote detection of structural displacements is experimented as geotechnical instrument for static and dynamic testing of bridges. The sensor is based on an interferometric radar providing range imaging capability and sub-millimetric accuracy range displacement measurement. Dynamic monitoring calls for sampling rate high enough for transient analysis, while static monitoring requires long-term stability. The instrument has been designed in order to provide both these features. The results of a validation campaign on a railway bridge during the final test before going into service are reported.

Dynamic Monitoring of Bridges Using a High-Speed Coherent Radar

Abstract: Remote dynamic monitoring of bridges by a high-speed interferometric radar is proposed. The equipment is a continuous-wave step-frequency radar with very fast frequency hopping that is capable of sampling the structure at a rate high enough for transient analysis of motion through phase comparison of successively acquired images. An experimental test carried out on a highway bridge forced by vehicular traffic is presented

Interferometric radar vs. accelerometer for dynamic monitoring of large structures: An experimental comparison

Abstract: Interferometric radar has been recently proposed as a measurement instrument for dynamic testing/monitoring of large structures, such as bridges, towers, buildings, and dams, which is currently performed by networks of accelerometers. In this paper, the authors report a direct comparison between the two measurement techniques (radar interferometer vs. accelerometers) both employed during a field test on a bridge. As different quantities, displacement and acceleration are measured by the two techniques, a preliminary discussion about signals and noise has been necessary. Finally, the experimental results are critically discussed.

A Review on Recent Progress of Portable Short-Range Noncontact Microwave Radar Systems

Abstract: This paper reviews recent progress of portable short-range noncontact microwave radar systems for motion detection, positioning, and imaging applications. With the continuous advancements of modern semiconductor technologies and embedded computing, many functionalities that could only be achieved by bulky radar systems in the past are now integrated into portable devices with integrated circuit chips and printed circuits boards. These portable solutions are able to provide high motion detection sensitivity, excellent signal-to-noise ratio, and satisfactory range detection capability. Assisted by on-board signal processing algorithms, they can play important roles in various areas, such as health and elderly care, veterinary monitoring, human-computer interaction, structural monitoring, indoor tracking, and wind engineering. This paper reviews some system architectures and practical implementations for typical wireless sensing applications. It also discusses potential future developments for the next-generation portable smart radar systems.

Through-Wall Imaging via a Linear Inverse Scattering Algorithm

Abstract: A through-wall imaging problem for a 2-D scalar geometry is addressed. It is cast as an inverse scattering problem and tackled under the linear model of the electromagnetic scattering that is provided by the Born approximation. A truncated singular value decomposition inversion scheme is exploited, and the performances that are achievable by such an inversion scheme are assessed by exploiting synthetic data. The cases of weakly and strongly scattering objects are both considered. Finally, an example of reconstruction that is obtained by exploiting experimental data is presented.

An interferometric radar for non-contact measurement of deflections on civil engineering structures: laboratory and full-scale tests

Abstract: Recent progress in radar techniques and systems has led to the development of a microwave interferometer, potentially suitable for non-contact vibration monitoring of civil engineering structures. The main characteristic of the new radar system, named IBIS-S, is the possibility of simultaneously measuring the (static or dynamic) displacement at several points of a structure with high sensitivity. The paper first describes the technical characteristics of the microwave interferometer and the results of laboratory tests carried out to evaluate the actual displacement sensitivity of the equipment. Subsequently, the application of the sensor to the measurement of ambient vibration response on a concrete bridge is presented and discussed.

Progress and trends in nondestructive testing and evaluation for wind turbine composite blade

Abstract: Wind energy is one of the fastest growing renewable energy resources. It is distinctly important to increase reliability and availability of wind turbines and further to reduce the wind energy cost. Blades are considered to be one of the most critical components in wind turbine system because they convert Kinetic energy of wind into useable power. Blades are fabricated by carbon fiber reinforced polymer (CFRP) or glass fiber reinforced polymer (GFRP). Flaws and damages are inevitable during either fabrication or lifetime of a composite blade. Thus, non-destructive testing (NDT) and structural health monitoring (SHM) for wind turbine blade (WTB) are required to prevent failures and increase reliability in both manufacturing quality control and in-service inspection. In this work, a fully, in-depth and comprehensive review of NDT techniques for WTB inspection was reported based on an orderly and concise literature survey. Firstly, typical flaw and damage occurring in manufacturing progress and in service of WTB were introduced. Next, the developments of visual, sonic and ultrasonic, optical, electromagnetic, thermal and radiographic NDT for composite WTB inspection were reviewed. Thereafter, strengths and limitations of NDT techniques were concluded through comparison studies. In the end, some research trends in WTB NDT have been predicted, for example in combination with SHM. This work will provide a guide for NDT and SHM of WTB, which plays an important role in wind turbine safety control and wind energy cost savings. In addition, this work can benefit the NDT development in the field of renewable energy, such as solar energy, and energy conservation field, such as building diagnosis.