In this paper, a structural health condition monitoring method for the cryotanks based on impedance and Lamb waves is presented. The method consists of four stages: environmental awareness, damage prewarning, sensor network self-diagnosis, and structural damage detection. In the environmental awareness stage, the change of environmental temperature is monitored by the changing trend of the sensor impedance signal. Under the condition of temperature stability, the baseline signal space of impedance and Lamb waves are established to avoid the influence of temperature change on the diagnosis accuracy. In the damage prewarning stage, the root-mean-square deviation between the impedance signals of different conditions is interpreted as a prewarning factor of possible damage. In the sensor network self-diagnosis stage, the state of the sensor is monitored by analyzing the impedance signal characteristics. In the stage of damage diagnosis, the damage index is extracted by comparing signals from different conditions, and it is adjusted according to the sensor state. The final results of the structural health monitoring method include the structural health status and sensor network status. Finally, the effectiveness of the method is verified by the cryogenic delaminating damage monitoring test of the composite structure.
Impedance- and Lamb-Waves-Based Health Condition Monitoring Approach for Composite Cryotanks
Journal of Spacecraft and Rockets ; 57 , 5 ; 1069-1078
2020-05-20
10 pages
Aufsatz (Zeitschrift)
Elektronische Ressource
Englisch