OPTIMAL DESIGN AND SIMULATION OF SANDY LOAM SOIL COVERING DEVICE BASED ON BIONIC SAND CRAB PINCERS

Aiming at the problems that the soil covering machine of the seeder is prone to, such as uneven soil covering thickness and seed position deviation, which affect the sowing quality under sandy loam soil conditions, an innovative disk-type soil covering device based on the bionic shape of the claw legs of sand crabs has been optimized and designed. In this study, the contour features of the pincers of sand crabs were extracted using MATLAB software and applied to the tooth profile design of the soil cover plate, aiming to improve their operational performance in sandy loam soil. This study analyzed the operation mechanism of the bionic soil covering device based on the characteristics of sandy loam soil and determined the key parameters affecting the soil covering effect, including the installation deflection angle, installation inclination angle and the distance between the openings at the back of the soil covering tray. Taking the qualified rate of soil cover thickness and the standard deviation of seed lateral displacement as evaluation indicators, and with the help of EDEM discrete element simulation technology, the interaction model of sandy loam - seed - bionic soil cover device was constructed, and the single-factor and Box-Behnken response surface experimental designs were systematically carried out. Through simulation analysis and optimization, the optimal parameter combination of the soil covering device suitable for sandy loam soil was determined as follows: installation deflection angle 21.3°, installation inclination angle 20.1°, and the opening spacing behind the soil covering tray 100.0mm. It has laid a foundation for the research on improving the uniformity of soil covering and the straightness of seed rows in the soil covering device of sandy loam soil seeders.