Research On Self Balanced Traction Control Strategy Of Electric Monorail Weeding Agricultural Machinery

With the rapid development of mechanized agriculture,the level of automation of agricultural machinery in China is relatively low,which greatly reduces the efficiency of agricultural production.Our country land management is the combination of cooperation and contract system management pattern,but most farmers do not wish to participate,often choose business alone,presents the farmland smaller and is not suitable for large agricultural machinery field control situation,the small agricultural machinery is the trend of application of the small agricultural machinery mostly need manual operation,greatly enhance the farmers’ labor and operation difficulty,because the field width different line spacing,farm machinery volume does not match with the field line spacing,lead to row operations rolling crops,wastes the inevitable.Aiming at the problem of inter-row operation of agricultural machinery,this study designed an electric monorail self-balancing weeder.Due to the narrow body and simple structure of the monorail structure,the agricultural machine can effectively avoid the problem of the mismatch between the traditional electric weeder and the row spacing.It is suitable for weeding in the field,with lighter weight and less compaction and damage to the soil.Moreover,the equipment has the function of automatic leveling,which greatly reduces the difficulty of farmers’ work.The main research contents and results of this paper are as follows:（1）According to the principle of equipment balance and working conditions.Through the analysis of gyro balance principle,it can be known that the moment produced by gyro precession is related to the moment of inertia,precession angular velocity and rotation angular velocity of rotor.Based on this principle,an electric double wheel self balancing weeding agricultural machinery equipment is designed.Firstly,the structure of the equipment is designed.According to the weeding operation requirements,the propulsion motor with rated power,voltage and speed of 7W,3V and 50 R / min,the self rotating motor with 260 W,12V and 20640 r / min,the hub motor with 250 W,36V and 500 r / min and the power battery with rated capacity of 30A·h are selected.the gear dynamic analysis and the Lagrange equation and euler matrix method to set up the dynamics model of self balancing weeding farm machinery,use SOLIDWORKS to establish a three-dimensional model of equipment,equipment fuselage barycentric coordinates（0.57,0,0.32）,moment of inertia of the rotational inertia of the fuselage and product I_bxx,I_byy,I_bzz,I_bxz were 3.79 kg·m² and 17.81 kg·m² and 14.32 kg·m² and 5.41 kg·m²,The moment of inertia of the rear wheel I_rxx,I_ryy and I_rzz are 0.08 kg·m²,3.0 kg·m² and 2.93 kg·m² respectively.The moment of inertia and the product of moment of inertia of the front wheel are Itxx,I_tyy,I_tzz and I_txz are 0.04 kg·m²,0.07 kg·m²,0.04 kg·m² and 0.23 kg·m² respectively.The dynamic model verification analysis shows that the device has good observability,stability and controllability.（2）A self-balancing model is designed based on fuzzy PID control and precession return to zero compensation algorithm,and the simulation experiment is carried out in MATLAB.The results show that when there is no precession compensation,the gyro of the electric self-balancing traction system will maintain a large precession angle,while the anti-interference ability of the traction system is relatively low;when the precession angle is too large,the gyro will fail.Affect the balance control of the electric self-balancing traction system;after adding precession angle compensation,the precession angle of the electric self-balancing traction system will drop to about 10°of the set compensation boundary,and the descent speed is positively correlated with the precession angle compensation coefficient.When the angle is turned to 30°,the roll angle of the fuselage will be tilted to a certain extent but eventually stabilizes at around 0.5°.（3）Based on the control algorithm,an equipment controller with STM32F103VET6 as the processor is designed.The controller is assisted by control algorithm,MPU9250,L298 N,Angle sensor and ultrasonic range sensor to realize the body balance,speed adjustment and steering control of the electric monorail weeder during operation,and to verify the selection of hub motor and power battery pack.The results show that the controller can realize the balancing,traction and steering functions of the equipment in field operation,and the selected motor and battery pack can meet the operation requirements greatly.