The desire to counteract impact loads on laminated structures in order to reduce ply damage has recently led to research using smart materials in laminated composites. The ability to sense the onset of these impact loads using piezoelectric material is the first step in the damage control process. This research focuses on smart laminated plates under impact and the electric field created by piezoelectric patches in the structure. A modified version of an existing finite element program is used to numerically simulate a laminated plate under a low velocity impact. Linear constitutive relations are used in the program which calculate the electric field generated by the in-plane strains on the piezoelectric plies. Several studies are made comparing the electric field generated by patches of piezoelectric material of varying size, shape, and location within the plate. The average electric field generated by larger patches which contain more oscillations of electric field filters the high frequency components. The distance between the impacting point and the piezoelectric sensor is found to be directly related to the lag time between the impact and generation of an electric field.

Date Published: 12 July 1993
PDF: 12 pages
Proc. SPIE 1918, Smart Structures and Materials 1993: Smart Sensing, Processing, and Instrumentation, (12 July 1993); doi: 10.1117/12.147983

Published in SPIE Proceedings Vol. 1918:
Smart Structures and Materials 1993: Smart Sensing, Processing, and Instrumentation
Richard O. Claus, Editor(s)