(Sepcial) Advances in Health Monitoring and Sensing Technologies for Aerospace System - I
Chair: Prof. Sangchul Lee (Korea Aerospace University)
New prognostics-based structural maintenance strategies for civil aircraft Prof. Christian GOGU (Universite Toulouse III)
Currently, structural maintenance of civil aircraft is based on the scheduled maintenance strategy, where all the aircraft of a same model are inspected according to a predetermined schedule. Embedding sensors in aeronautical structures allowing to monitor their structural health can also open up new strategies for more efficient maintenance planning. A first possibility is to move from scheduled maintenance to condition based maintenance, where the current condition of the aircraft triggers specific maintenance policies. A further step is to not only use the current state of the damage but to also predict future damage growth and determine the maintenance policy accordingly. Both condition based as well as prognostics based strategies can be carried out independently or can be coordinated with other, scheduled, non-structural maintenances, which leads to a total of four new possible maintenance strategies. An application of these maintenance strategies to fuselage panels of a short range commercial aircraft is presented and their effectiveness and cost-efficiency is compared between them and with that of traditional scheduled maintenance. We show that large savings can be achieved, particularly when large variabilities are present.
A Preliminary Study for Aircraft Engine Health Management based on Multi-scale Kalman Filters Prof. Joo-Ho CHOI, Seokgoo KIM, Yuri YUN and Heeseong KIM (Korea Aerospace University, University)
Aircraft engine is directly associated with flight safety. Its unpredicted failures lead to catastrophic accident and down-time. To prevent these problems, prediction of the accurate remaining useful life of engine is essential. With the rapid development of sensor technology, engine health condition can be monitored with multiple sensors. Therefore, it is important to develop suitable methodologies of integrating various data to improve the accuracy of remaining useful life. This paper attempts to establish an integrated method based on multi-scale Kalman Filters (MSKF) to implement the on-board fault detection which investigates the abrupt state change real-time to ensure safe flight and the off-board health estimation that evaluates the current degradation state and predicts the remaining life for prepare its replacement in advance. Due to the inability to access the code for engine performance simulation, Electrohydraulic Flight Actuator (EHA) is employ to study the feasibility of the approach in this study. The system includes three sub-system models: motor, pump and hydraulic cylinder that are coupled with each other. MSKF is implemented with one for the on-board real-time fault detection and the other for the off-board long-term health degradation. MSKF is recently proven feasible for battery health management where the SOC (short time scale) and SOH & RUL (long time scale) are estimated concurrently. Artificial data for the actuator performance are generated under the scenario that it encounters abrupt fault in the middle of cycle while the actuator undergoes long term health degradation.
Development of the Aircraft Structural Health Monitoring Equipment integrating Optical Sensor and Analog Sensor Mr. Kyeung Sik CHOI, Sang yong KIM, Cheol joo LEE and Han soo YUN (Danam systems, Agency for Defense Development, Korea Aerospace Industries)
The structure of the aircraft has made lots of effort to secure the safety, and the safety is remarkably secured through the lifetime management and the non-destructive inspection. However, periodic inspection requires much time and expense, and various monitoring techniques for aircraft structures are required, especially when the SHM technique is studied for composite structures that can not use traditional lifetime management techniques. For this monitoring perform, the predeveloped analog sensor has a limit in durability limitations and cable weight. Therefore, the demand for the monitoring equipment of the new technique has been increasing, and FBG and PZT sensor are used representatively. In this paper, we have developed a device that can acquire analog sensor(Accelerometer, Strain gage) and FBG sensor, and support interworking with the Air Data Bus(MIL-STD-1553B, Ethernet) for real-time analysis. Also, it is satisfied a various military environmental requirements for use in military aircraft. The equipment which is introduced in this paper is expected to be used for SHM and lifetime management.