Tractor automatic navigation control system and method thereof

Abstract

The invention provides a tractor automatic navigation control system. The system comprises a navigation control device, a steering control unit and an electro-hydraulic proportion steering executing device, wherein the navigation control device receives GPS positioning data in real time, calculates a lateral deviation between a current tractor position and an operation navigation target, calculates a target steering angle of a steering wheel in a current control period according to the lateral deviation and a tractor running speed value measured in real time, converts the target steering angle into a steering control command and then sends the steering control command to the steering control unit; the steering control unit judges whether a steering angle measured value of the steering wheel of the tractor is less than a preset limit value; if the steering angle measured value is less than the preset limit value, the steering control unit compares the target steering angle with the measured value, calculates a PWM duty cycle according to a steering angle difference value and outputs a control signal for driving the electro-hydraulic proportion steering executing device; and the electro-hydraulic proportion steering executing device responds to the PWM control signal and controls the flowing direction and the flowing speed of oil of a tractor steering system by the opening of a valve core of an electro-hydraulic proportion direction valve to make a piston of a steering hydraulic cylinder extend out or retract to deflect the steering wheel to the target steering angle.

Description

technical field [0001] The invention relates to the technical field of control, in particular to an automatic navigation control system and method suitable for hydraulic steering tractors. Background technique [0002] During the field operation of tractors, due to the poor maneuverability of the operation unit, it is easy to affect the productivity due to heavy plowing, missed plowing or extra distance. In order to reduce the occurrence of rework and missed work between adjacent working ridges, the existing technology mostly uses the method of marking with a marker or spraying foam to mark in the field as the basis for the driver's work navigation. With the development of domestic precision agricultural technology research in recent years, researchers have developed an agricultural machinery navigation system, which uses GPS, PC104 computers and navigation light sticks to provide navigation instructions for agricultural machinery field operations. However, there are certai...

AI Technical Summary

Problems solved by technology

However, there are certain defects in the above two navigation instruction methods for agricultural machinery operations.

[0003] The traditional method of marking with a liner and spraying foam is basically infeasible or the navigation indication effect is poor when the visibility of the farmland operation environment is low, there is no obvious reference on the farmland surface, and the ground surface is undulating. The purpose of improving the quality of work

[0004] Most of the existing navigation indication systems use RS232 / RS485 bus, which leads to complicated system wiring and poor reliability, and the versatility and compatibility of each module of the system are not strong

At the same time, this type of navigation and indication system is greatly affected by human operation factors, and the navigation accuracy of the operation is poor, which cannot meet the application requirements of high-precision farmland operations such as sowing.

In addition, the operation and control of the existing navigation indication system still needs to be completed by the driver. In fact, it is an auxiliary operation navigation system, and the labor intensity of the driver is still relatively high.

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