| With the increase of population,the problems of environment and resources are particularly important in today’s society.How to realize the scientific regulation and distribution of existing resources and avoid resource waste is an important topic to realize sustainable development.The protection of environment and resources in agricultural production can be realized by saving water and fertilizer;Land leveling shall be carried out before or after farming according to seasonal farming time,so as to effectively improve irrigation efficiency and fertilizer utilization rate,avoid environmental pollution caused by excessive fertilization and increase income.Based on the study of GNSS leveling technology at home and abroad,a precise leveling system based on gyroscope attitude measurement,GNSS positioning technology and automatic control technology is designed.The research content of this paper is mainly divided into the following aspects:Firstly,through the research on the existing graders at home and abroad,starting from the working principle of the grader,this paper analyzes the actual needs of the grader in the work,and designs and selects the hardware system of the grader.In order to solve the sudden situation in the process of leveling,a controller which can realize manual and automatic control is designed.Then,according to the working characteristics of the grader,the attitude control method of the grader is studied.Based on the relevant control theory(PID,PWM),the mathematical modeling method is used to analyze and model the control target(pitch angle and elevation).The flat control software is developed by using VB 6.0 software.Matlab r2021 a is used to digitally analyze the control system and test the system performance.After comparison,fuzzy PID and PWM are used to control the leveling system by adjusting the duty cycle of electromagnetic directional valve to avoid overshoot and vibration.Finally,in order to test whether the leveling system can operate stably,a field experiment is carried out;After the topographic survey,the leveling operation is carried out.After the operation,the three indexes of flatness,height difference distribution column and maximum height difference are improved differently.The flatness increases by 50%,the height difference distribution column increases by 32%,and the maximum height difference is 13.7cm.The test results show that the automatic control system of farmland grader based on gyroscope can work stably.Improve farmland topography to meet work requirements. |
