Impact on composite laminated plates: An inverse method

A method is developed to detect the impact force history exerted on a laminated composite plate of rectangular dimensions from the recorded strain responses. The impact duration considered is in the order of 1 ms, which is frequently encountered in composite laminates struck by a foreign object at low velocities. A Green's function is constructed based on the classical lamination theory and the model superposition method to correlate the laminate response to the impact force. Instead of obtaining the impact force history through the direct deconvolution process of a convolutional integral, a constrained optimization technique is employed, and a convergent criterion is also proposed. The method is verified using both the signals numerically generated with a signal-to-noise of 2.0 and experimental data. The agreement is very satisfactory in all the comparisons. This verifies the proposed method.