Abstract: Using the ANSYS software to sunflower combine impulse sensor on the structure of the pneumatic conveying the fluid-structure coupling modal analysis, studied the presence of fluid-structure interaction, impact plate materials and impact plate clamped on the natural frequencies and formations, the influence of the pulse sensor and analyses the influence of natural frequency pulse sensor harvester output accuracy of measurement. Experimental results show that: The greater the natural frequency of the impulse sensor, the better the stability and sensitivity of the system; The fluid-structure coupling effect obviously increases the first natural frequency of the impulse sensor, but does not change the natural array. The impact plate material affects the first-order natural frequency of the impulse sensor, and the impact plate material has little effect on the formation when the material characteristics of the impact plate are similar. The maximum first-order natural frequency of the impact sensor of the acrylic material impact plate is 46.913 Hz. The fixed mode of the impact plate affects the natural frequency and formation of the impulse sensor, among which the first natural frequency of the intermediate fixed mode is 35.548 Hz at most. Through the verification test of sunflower production test bed, the maximum relative error of the impulse sensor of acrylic impact plate is at least 2.1%, and the maximum relative error of the impulse sensor of intermediate fixed support is at least 2.37%.The rationality of simulation analysis is verified.