Practical issues in real-world implementation of structural health monitoring systems

Abstract

Currently, there exist several different types of structural health monitoring (SHM) systems that are in the stage of development and/or are being tested for use in real-world applications. For a number of years, Structural Health Monitoring (SHM) systems have demonstrated feasibility in laboratory and controlled testing environments. Acellent has been developing and testing strategies to bring the SHM field to the next level. These include issues involved with system installation, calibration, reliability and connections for structures fabricated with composite materials. Composite structures are susceptible to hidden or barely visible damage caused by impacts and/or excessive loads that if unchecked may lead to lower structural reliability, higher life-cycle costs, and loss in operational capability. Current maintenance and inspection techniques for in-service composite structures can be labor-intensive and time-consuming. Utilization of an integrated sensor network system such as that developed by Acellent can greatly reduce the inspection burden through fast in-situ data collection and processing. Using a built-in network of actuators and sensors, Acellent Technologies is providing the tools required for a practical SHM system. In this paper, key development and testing issues concerning real-world implementation of the SHM system on composite structures are presented.

Integrated Sensor Durability and Reliability

“…The performance and reliability of layered piezoelectric actuator/sensor networks was recently evaluated by Kusaka and Qing [70] and Beard et al [71,72] (see Stanford Multiactuator-Receiver Transduction (SMART) Layer Technology and Its Applications). In those efforts, the mechanical loading durability, environmental reliability, and overall system reliability of Acellent's Stanford multiactuator receiver transduction (SMART) layer technology [73] were studied, respectively.…”

“…Testing results for the SMART Layer system were highlighted in that effort, where environmental conditions (temperature, moisture, chemical attack) were considered as well as mechanical shock/loading, and intense fatigue testing. In general, the results indicated that the layered piezoelectric actuator/sensor networks did not lose functionality for most realistic operational conditions [71]. The need for self-diagnosis, sensor redundancy, and environmental compensation was also discussed with regard to improving overall system reliability [72].…”

“…Regarding sensor durability and reliability, the use of sealed electrical connectors, sensor system encapsulation/coating, optimized adhesive bonding, and sensor networks integrated on a flexible thin-film material (polyamide) provided for a rugged SMART Layer design [71][72][73]. The use of multiple distributed sensors also provided the system with sensor redundancy and opportunities for implementing self-test procedures.…”

Advances in Health Monitoring and Management

“…As illustrated in Figure 22 [49], in the active mode, an electric pulse is sent to a piezoelectric actuator that produces Lamb waves within the structure under evaluation. The array of piezoelectric sensors will pick up the resultant Lamb waves for processing and analysis.…”

Optimal Estimation of Deterioration From Diagnostic Image Sequence

“…This system uses a network of distributed piezoelectric sensors/actuators embedded on a thin dielectric carrier film called the SMART Layer R , see [3], [4]. The SMART Layer technology has both active and passive sensing capabilities via the embedded piezoelectric transducers, see Figure 3.…”