DESIGN AND EXPERIMENTAL STUDY OF A VEHICLE-MOUNTED FERTILIZING AND SPRAYING MACHINE

In order to solve the problems of low efficiency of fertilization and spraying in the hilly mountains of China, a vehicle-mounted fertilization and spraying machine was designed. The whole structure and working principle of the machine were described, and the key components of fertilization and spraying are designed. The kinetics and kinematics of fertilizer particles and droplets were modeled by theoretical analysis of their motion characteristics in the air. The fertilization and variable spraying control system based on the core controller MCU (Microcontroller Unit) was set up. And the system can adjust the rotational speed of the disc and can automatically change the spraying volume by real-time detection of forward speed to achieve a constant spraying volume per unit area. The test results showed that: when the disc speed was greater than 90 r/min, the uniformity coefficient of variation was less than 15%, which satisfied the operational requirements; the uniformity coefficient of variation reached the minimum value of 10.03% when the disc rotation speed was 180 r/min, and the best fertilization performance was achieved at this time. In the spraying system, the actual spraying volume increased with the increased forward speed, and the relative error between the theoretical flow rate and the actual flow rate was 6.25% at most, and the average error was 5.94%, which could achieve the purpose of variable spraying. The research results can provide technical reference for the design and development of fertilization and spraying machinery in hilly areas.