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Special issue on a structural health monitoring project for a composite unmanned aerial vehicle wing

The main objective of structural health monitoring (SHM) is to trace the performance of a structure with the assistance of advanced sensing technology and issue an alarm when any abnormality of the structure is identified. This special issue presents the outcomes of KASHMOS research project developed under the auspices of the Agency for Defense Development in Korea from 2008 to 2011. The project focused on the development of onboard and ground SHM hardware systems and algorithms that can be applied to monitor loading and detect damage in composite unmanned aerial vehicle (UAV) wings. Through the project, sensor-integrated composite wings, onboard sensor-interrogation device, ground inspection station, and monitoring algorithms were developed. This special issue consists of five papers that touch various aspects of the online and ground monitoring systems developed by seven research groups under the KASHMOS project. The paper by Park et al. 1 titled ‘An SHM project for a composite UAV wing: overview and evaluation tests’ provides an overview of the research project and gives brief descriptions on the SHM system architecture, operational scenario, developed components, and evaluation tests. The paper by Jang et al. 2 titled ‘Real-time impact identification algorithm for composite structures using fiber Bragg grating sensors’ proposes a neural network-based real-time impact identification algorithm for composite wing structures by using fiber Bragg grating sensors and giving verification results in a composite wing box. The paper by An et al. 3 titled ‘Airplane hot spot monitoring using integrated impedance and guided wave measurements’ presents an integrated impedance and guided wave damage detection technique for online monitoring of critical hot spots within a composite airplane structure using piezoelectric transducers. The paper by Chia et al. 4 titled ‘Composite aircraft debonding visualization by laser ultrasonic scanning excitation and integrated piezoelectric sensing’ introduces a damage visualization approach using a laser-based ultrasonic propagation imaging system for manufacturing defects and debonding mode damage of composite aircraft wings. The paper by Shin et al. 5 titled ‘Assessing a joint integrity of a lug assembly using piezoelectric active-sensors’ investigates the use of piezoelectric active-sensing SHM techniques, including high-frequency response functions and time-series predictive models, for detecting joint loosening modes in a lug assembly in the presence of ambient temperature changes. The assistance of the editors and editorial staff of Structural Control and Health Monitoring in hosting this special issue and expediting the review of the papers is much appreciated.