Objective To clarify the collision damage mechanism of cassava seed stems during the seeding process and seek a seeding method with less damage.

Method Using 3D scanning technology to reversely establish a 3D model of cassava seed stem, and through finite element analysis of seed stem collision based on Hyper Mesh and LS-DYNA, the main influencing factors of seeding performance (drop height, installation inclination angle of vibration plate, and vibration frequency of vibration plate) were studied to investigate the process of seed stem collision damage. The variation law of the equivalent stress of the contact between the seed stem bud and the sowing component slope, the equivalent stress at the junction of seed bud and stalk, the strain at the junction of seed bud and stalk, and the strain of seed bud and sowing components slope contact at different experimental factor levels were clarified. On the basis of single factor experiments, a quadratic rotation orthogonal combination experiment was conducted to study the influencing factors, combined with nonlinear multi-objective optimization calculation methods, in order to verify the rationality of the established regression model.

Result When the drop height was 167.83 mm, the installation inclination angle of the vibration plate was 22.18°, and the vibration frequency was 66.96 Hz, the equivalent stress of the oblique contact between the seed bud and the sowing component was 32.64 MPa, the equivalent stress of the intersection between the seed bud and the stalk was 17.08 MPa, the strain of the intersection between the seed bud and the stalk was 0.094, and the oblique contact strain of the seed bud and the sowing component was 1.049. The predicted results of the model were similar to the actual simulation results, proving the reliability of the regression model.

Conclusion The results provide a theoretical basis for revealing the collision mechanism of cassava seed stems and optimizing the seeding device.