Research On Control Technology Of Tilling Depth Of Electro-hydraulic Suspension System Of Large Tractor

As an important tool for farming,the large tractor is an important branch of intelligent agricultural machinery equipment to study its depth control technology in complex operating environments.At present,there is a single research on tractor tillage depth control methods in China,and no in-depth research has been carried out on the multi-factor discussion.Therefore,according to the actual operating environment and the characteristics of the tractor’s electro-hydraulic suspension system,a depth-control method based on three-parameter adjustment of resistance-position-slip rate based on sliding mode variable structure control is constructed to effectively improve the cultivation quality.Design the control plan of the depth of the large tractor.First of all,according to the functional principle of the electro-hydraulic suspension system,the key core components are selected and designed,and the advantages and disadvantages of different tillage depth adjustment methods are analyzed and analyzed,and then the resistance-position-slip rate adjustment scheme is designed,and its principle and flow chart arc designed,And then combined with the selection to establish its mathematical model,and build a simulation model to verify the steady state of the working unit.Model and analyze the electro-hydraulic suspension system and the depth control algorithm of large tractors.Firstly,combined with the non-linear characteristics of the tractor operation unit,mathematical modeling of the electro-hydraulic suspension system,comparative analysis of various control algorithms,selection of fuzzy PID control algorithm and sliding mode variable structure control algorithm and design of the controller.At the same time,the Matlab/Simulink software platform is used to compare and analyze the response characteristics of the two algorithms,which proves that the sliding mode variable structure controller has short response time and strong stability,and has excellent response characteristics and anti-interference performance.Simulation and verification of the depth adjustment scheme of sliding mode variable structure control algorithm.Under specific environmental conditions,the simulation curves of resistance-position adjustment and rcsistance-position-slip rate adjustment when the average soil specific resistance is 3N/cm2,4N/cm2,and 5N/cm2 are analyzed separately.Through comparative analysis,the excellent performance of the resistance-position-slip rate adjustment scheme is verified,and it can better adapt to the complex and changing farming environment.Controller design and experimental research are carried out.Combined with the existing test conditions,the design and development of the main program and main module subprogram of the control system were completed with STC89C52RC as the main control chip,and then a field ploughing test platform was built,and the field was developed for the control algorithm and adjustment scheme designed in this paper.The comparison test verifies that the resistance-position-slip rate adjustment scheme based on sliding mode variable structure control can achieve the expected function.