关键词: 玉米免耕播种机, 指夹式排种器, 振动, 时频分析, 排种性能

Abstract: In order to study the vibration characteristics of maize notillage seeder and the influence of vibration on the leakage index and reseeding index of the seeder, a vibration test system composed of vibration acceleration sensor, charge amplifier and USB acquisition card was set up. A vibration test was carried out to collect the vibration signal of the sowing operation during the notillage surface operation of the corn notill planter. Due to the complex working environment in the field, the IIR filter in the classical filtering method was used to filter out other highfrequency interference signals of the collected vibration signals. The time domain analysis was carried out on the vibration signals collected in the field, and the mean square value was used as the time domain analysis index value. The analysis results showed that the root mean square of vibration acceleration increased linearly with the increase of operating speed and rotational speed of rotary tillage, and the rotational speed and operating speed of rotary tillage were the main factors that caused the vibration of corn notill planter. The order of influence  was: rotary tillage speed > working speed. Through using the quadratic integration method to analyze the collected signals in the field, it was concluded that the maximum vibration displacement of the planter was 16.004 mm. The vibration signal was analyzed in the frequency domain, and the power spectral density was obtained by the direct method. The results showed that the vibration frequency of the corn notill planter was mainly between 0-100 Hz. The frequency distribution and rotary tillage speed had a great influence. According to the working parameters obtained from the field vibration signal, a vibration test bench was built, and the vibration frequency, vibration amplitude and working speed of the seeder were used as test factors, and the pass index and missed seeding index were used as evaluation indicators to conduct a threefactor and threelevel response surface test. The analysis results showed that the working speed, vibration amplitude and vibration frequency had significant effects on the pass index and missed broadcast index. The order of the influence of each factor on the qualification index  was: vibration amplitude, working speed and vibration frequency, the order of each factor on the missed seeding index  was: vibration amplitude, vibration frequency and working speed. The research results of this paper can provide theoretical reference for reducing the vibration of maize notill seeder and optimizing the finger clip seed feeder.

Key words: corn no-tillage seeder, finger-clip seed metering device, vibration, time-frequency analysis, seeding performance