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In order to enhance the ability of response signal to reflect eggshell crack information and improve the accuracy of eggshell crack detection, structural parameters and detection conditions of the excitation stick were optimally designed by dynamic experiments based on mechanical model of the knocking device. The shape of pulse produced by excitation stick was related to the weight of stick, stiffness coefficient and percussion speed according to mechanics analysis results. The spectrum of excitation pulse was analyzed. The results showed that the sensitivity of response signals for eggshell creak information can be improved by reducing the pulse width and increasing the pulse peak. The excitation pulse signal was collected by a quartz force sensor, which was analyzed to optimize the excitation stick by using force spectrum method. In order to ensure that the main lobe band of the excitation force pulse covered the natural frequency of eggs, the weight of the optimized excitation stick with nylon striking end was less than 5.6g. The relationship model between the pulse peak and the stick percussion speed was established, which would offer a reference to select the appropriate percussion speed for different varieties of eggs. The mathematical model of the transient impulse process was established to provide the basis for the later finite element simulation. The experiment results showed that the excitation pulse produced by the optimized excitation stick had the advantage of good stability, and the correlation coefficients between the pulse of intact eggs and mathematical model were more than 0.92. Frequency band of the pulse could cover the natural frequency of eggs and the pulse had sufficient excitation energy, which were of great help to distinguish between intact eggs and crack eggs and increase the signal to noise ratio (SNR) of response signal.