Abstract:When an aircraft, spacecraft, automobile, ship, or other engineering facility is impacted by other objects during service, the damage caused by the component may cause a failure of the component or even a catastrophic accident. How to take effective measures to monitor and assess such active impact damage is essential. To locate impact damage precisely in real-time in an engineering structure, a non-contact impact damage location method based on scanning laser Doppler vibrometer (SLDV) was proposed in this paper. The Hilbert-Huang Transform (HHT) was applied to the signal processing to obtain the best response frequency spectrum. The separated IMF1 was used in the circular trajectory positioning imaging of amplitude total addition and amplitude multiplication. The experimental results indicate that HHT can be used to achieve non-contact impact damage localization of composite materials.