Omni-directional impact localization method on composite structure using plum blossom array

Aiming at the problem of blind area using uniform linear array, impact localization method of 2D multiple signal classification (2D-MUSIC) using plum blossom array was investigated.The layout of plum blossom array consisted of one sensor in the center and M sensors uniformly spaced on circle with the radius R .First, the velocity of Lamb wave propagating was estimated by the time information of impact signal acquired by reference array element PZT0 and array element PZT1 which received impact signal firstly.Second, near-field 2D-MUSIC algorithm was applied to localize the distance and direction of impact source simultaneously.Finally, the experiment on the glass fiber composite laminates was established to verify the validity of the impact localization method.Experimental results show that plum blossom array based impact localization method could localize impact source from 0° to 360° accurately, whose maximum error of distance and direction error is 2.2 cm and 5° respectively.