Attitude regulation and control system for farm implement of tractor in hilly and mountainous areas

Abstract

The invention belongs to the technical field of agricultural machinery farm tool posture regulation and control, and particularly relates to a hill and mountain tractor farm tool posture regulation and control system which comprises a CPU module, a hydraulic valve control module, an execution mechanism module, a sensor module and an early warning module. The CPU module comprises a particle swarm fuzzy PID (Proportion Integration Differentiation) controller and a limiting information processing unit; the hydraulic valve control module comprises a hydraulic oil tank, a filter, a hydraulic oil pump, an overflow valve, an electromagnetic proportional valve and a one-way throttle valve; the executing mechanism module comprises left and right lifting hydraulic cylinders, left and right lifting arms, left and right lifting rods, left and right lower pull rods and upper pull rods; in the specific using process, the posture of the tractor operation device can be rapidly and accurately adjusted and dangerous conditions can be early warned under the working condition of the slope land, the angle of the tractor operation device is always kept consistent with the angle of the slope land, and the agricultural productivity of hilly and mountainous areas and the safety and accuracy in operation work are improved.

Description

Technical Field

[0001] The present invention belongs to the field of agricultural machinery and implement posture control technology and control technology, and in particular relates to a tractor implement posture control system for hilly and mountainous areas. Background Art

[0002] Agricultural work in hilly and mountainous terrain often involves facing slopes of 6° to 15°. Hilly and mountainous tractors operating on slopes are prone to uneven plowing depths, which in turn affects operational efficiency and crop growth. To address this issue and meet the urgent needs of hilly and mountainous areas, major research institutes and universities have conducted research on the posture adjustment of the body and working device of hilly and mountainous tractors. Currently, hydraulic differential height technology is often used to adjust the working device of hilly and mountainous tractors. Its main principle is to use left and right hydraulic cylinders to keep the working device level with the slope. Traditional hydraulic actuators, with hydraulic cylinders directly connected to the working device, lack stability and are prone to shaking when encountering extremely bumpy roads, thus affecting work quality. Currently, the hydraulic adjustment control method for the working device of hilly and mountainous tractors mostly uses fuzzy control, a nonlinear control method that generally exhibits good control performance. However, fuzzy PID controllers also have some shortcomings. For example, the determination of quantization and scaling factors, the selection of membership functions, and the formulation of fuzzy rule tables can significantly affect control effectiveness. These issues rely heavily on expert and engineering experience and cannot fully cope with interference under special conditions, thus affecting adaptive capabilities and control effectiveness. Therefore, it is particularly important to design a hilly and mountainous tractor implement posture control system that can automatically adjust and operate stably and reliably under slope conditions, and always maintain consistency with the slope angle. Summary of the Invention

[0003] The purpose of the present invention is to provide a tractor implement posture control system for hilly and mountainous areas. During specific use, the present invention can enable the tractor operating device to quickly and accurately adjust the operating device posture and issue early warnings of dangerous conditions under slope conditions, always maintaining consistency with the slope angle, thereby improving agricultural productivity in hilly and mountainous areas and improving the safety and accuracy of operations.

[0004] In order to achieve the above object, the present invention adopts the following technical solutions: A hilly and mountainous tractor implement posture control system, comprising a CPU module, a hydraulic valve control module, an actuator module, a sensor module, and an early warning module; The CPU module includes a particle swarm fuzzy PID control unit and a limit information processing unit; The hydraulic valve control module includes a hydraulic oil tank, a filter, a hydraulic oil pump, a relief valve, an electromagnetic proportional valve, and a one-way throttle valve; The actuator module includes left and right lifting hydraulic cylinders, left and right lifting arms, left and right lifting rods, left and right lower pull rods, and upper pull rods; The sensor module includes a hydraulic cylinder displacement sensor, a vehicle body posture lateral posture inclination sensor and a working device posture lateral posture inclination sensor; The early warning module includes a display screen, a buzzer, and a reset button; The sensor module can monitor various posture information, generate electrical signals and input them into the CPU module. The CPU module processes the electrical signals and generates adjustment signals through the PSO-Fuzzy PID control algorithm. After receiving the adjustment signals, the hydraulic valve control module controls the flow size and direction of the hydraulic oil circuit by controlling the input current of the electromagnetic proportional valve, and ultimately controls the extension and retraction of the left and right lifting hydraulic cylinders. The actuator module drives the movement of the adjustment mechanism through the extension and retraction of the left and right lifting hydraulic cylinders on both sides, forming a height difference through the movement of the adjustment mechanisms on both sides, thereby adjusting the lateral inclination angle of the working device. After receiving the posture and warning information electrical signals, the early warning module displays posture information such as the tractor body inclination angle, the working device inclination angle, and the hydraulic cylinder extension and retraction displacement on the display screen, and can issue an abnormal alarm through the buzzer.

[0005] The CPU module is used to convert, detect, filter, and amplify the attitude data signal output by the sensor module. The processed attitude angle data signal is used to calculate the hydraulic cylinder piston rod extension and contraction required for attitude adjustment in real time, and further processed through the PSO-Fuzzy PID control algorithm to obtain the current size of the forward or reverse connection of the electromagnetic reversing valve, and generate an adjustment control signal to be transmitted to the valve-controlled hydraulic module.

[0006] The CPU module is used to process the vehicle body lateral inclination angle signal, the agricultural implement lateral inclination angle signal, and the hydraulic cylinder displacement signal to determine whether they are within the set safety range. If they are beyond the safety range, the posture and warning information processing unit will send an alarm signal to the warning module, causing the warning module to issue an alarm; at the same time, the posture information and hydraulic cylinder extension and contraction amount information will be transmitted to the display screen of the warning module; the CPU module can receive the reset signal given by the warning module and process it, and transfer the processed adjustment control signal to the hydraulic valve control module.

[0007] The solenoid valve in the hydraulic valve control module adopts a three-position four-way solenoid valve. The hydraulic valve control module controls the direction and opening size of the solenoid valve valve core according to the adjustment electrical signal, and then controls the flow size and direction of the hydraulic oil in the hydraulic circuit, thereby controlling the telescopic displacement of the hydraulic cylinder.

[0008] The upper pull rod and the left and right lower pull rods in the actuator module are connected to the working device through a ball pin; the tail of the hydraulic rod of the left and right lifting hydraulic cylinders on both sides of the actuator module is connected to the lifting arm by a pin shaft, the lifting arm and the lifting rod are connected by a ball pin, and the lifting rod and the lower pull rod are connected by a pin shaft; the telescopic movement of the hydraulic cylinder is transmitted to the linkage mechanism of the actuator, and finally transmitted to the left and right lower pull rods, so that the left and right lower pull rods form a height difference, thereby changing the posture inclination angle of the working device.

[0009] The sensor module is used to detect the posture inclination angle of the tractor body in hilly and mountainous areas and indirectly measure the slope angle, the posture inclination angle of the working device, and the extension and contraction amount of the hydraulic cylinder piston rod of the working device. At the same time, it generates posture angle data signals and extension and contraction displacement data signals, and transmits the detection data signals to the posture and warning information processing unit in the CPU module for data analysis and processing.

[0010] The display screen in the early warning module can display the working device posture information transmitted by the CPU module. The working device posture information includes the angle of the vehicle body and the working device, and the extension and retraction of the hydraulic cylinder; when each posture data exceeds the set safety range, the buzzer will sound an alarm and the entire posture adjustment system will stop urgently; after an emergency stop occurs, the driver can check and clear the fault, and then operate the reset button in the early warning module to restore the working device to its initial state.

[0011] The particle swarm fuzzy PID control unit is used to control the posture adjustment of the working device through the particle swarm optimization fuzzy PID control algorithm (PSO-Fuzzy PID); the algorithm optimization process of the particle swarm fuzzy PID controller is to optimize the parameters in the fuzzy control; this is an optimization process to achieve optimal control of the system; for the posture adjustment control problem of the working device, the particle swarm optimization algorithm optimizes the fuzzy output Kp, Ki and Kd three PID control parameters of the fuzzy controller; the particle swarm fuzzy PID controller optimizes the current fuzzy control quantities Kp, Ki, Kd, ​​and obtains the global optimal PID parameter Kp of the current particle swarm through the particles. best 、Ki best 、Kd best And the global optimal parameter Kp best 、Ki best 、Kd best Feedback is sent to the hydraulic valve control module to perform telescopic displacement of the hydraulic cylinder to drive the actuator, adjust the attitude inclination angle of the working device, and thus realize the attitude control of the working device.

[0012] The particle swarm fuzzy PID control unit optimizes the current fuzzy control quantities Kp, Ki, and Kd, specifically comprising the following steps: Step 1. Set up the fuzzy controller: Set the fuzzy input variables e (error), ec (error change rate) and the fuzzy output variables Kp, Ki, and Kd. Use the Mamdani reasoning method for fuzzy reasoning and the area centroid method for clarification. Set the fuzzy language to PB (negative large), PM (negative medium), PS (negative small), ZO (zero), NS (positive small), NM (positive medium), and NB (positive large). Use triangular functions for the membership functions of both input and output quantities. Step 2. Initialize the particle swarm: Initially set the random position and velocity of the particle swarm; given the population size M and spatial dimension N, randomly generate the velocity vi and position xi of each particle; Step 3, fitness evaluation: Calculate the fitness of the particles according to the fitness function in the algorithm, and use the benchmark test function f(x) to calculate the current fitness value f(xi) of each particle. In this control system, the integral index of the product of time and absolute error is used to optimize the parameters of the fuzzy PID controller for the attitude adjustment of the working device. It can fully reflect the relationship between the deviation and time of the system. The smaller the value, the better. The expression can be described as:

[0013] Step 4. Update particle speed and position: Update the particle speed and position according to the fitness value using the following formula: Velocity update formula:

[0014] Position update formula:

[0015] At the same time, ensure that the particle position (PID parameters) is still within the preset range; Step 5. Update the historical optimal position: If the fitness of the current particle is better than its historical optimal fitness, update its historical optimal position Pi; at the same time, check and update the global optimal position Pg; Step 6. Determine the termination condition: Check whether the termination condition is met, such as reaching the maximum number of iterations or the fitness reaching the preset threshold; Step 7. Output result: Output the fuzzy output variable Kp corresponding to the global optimal position best 、Ki best 、Kd best , which is input into the PID controller as the optimization result to control the attitude adjustment device.

[0016] The tilt angle-hydraulic cylinder displacement converter in the particle swarm fuzzy PID control unit is used to convert the rotation amount required for the target tilt angle into the telescopic displacement amount of the hydraulic cylinder.

[0017] The beneficial effects of the present invention are as follows: the hilly mountain tractor agricultural implement posture control system provided by the present invention has the following characteristics and advantages when used: 1. The present invention employs a particle swarm fuzzy PID control method to automatically adjust the posture of the tractor's agricultural implements on slopes in real time, ensuring that the tractor's operating device remains consistent with the changing angle of the slope. Furthermore, the particle swarm fuzzy PID control method is used for posture adjustment. This control method is more responsive than the fuzzy PID control method, exhibits minimal overshoot error, and possesses adaptive learning and optimization capabilities, making operations more efficient and precise. 2. The present invention provides a posture control system for tractor implements in hilly and mountainous areas. It provides a posture adjustment device controlled by two hydraulic cylinders independently, which can realize synchronous and asynchronous movements of the left and right hydraulic cylinders. It realizes an early warning function, which can enable the driver to understand the posture information of the hilly and mountainous area tractor's working device in real time, and automatically stop the posture adjustment work in an emergency to ensure safe operation. A monitoring alarm is set to issue an alarm when the working device exceeds the limit tilt angle range to avoid useless work. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] Figure 1 This is a general layout diagram of a hilly and mountainous tractor implement posture control system provided by the present invention; Figure 2 This is a structural diagram of the actuator of a hilly and mountainous tractor implement posture control system provided by the present invention; Figure 3 This is a particle swarm optimization flow chart of a hilly mountain tractor implement posture control system provided by the present invention; Figure 4 This is a structural block diagram of a PSO-Fuzzy PID controller for a hilly mountain tractor implement posture control system provided by the present invention; Figure 5 The present invention provides a PSO-Fuzzy PID control simulation model for a tractor implement posture control system in hilly and mountainous areas; Figure 6 This is a PID controller parameter optimization curve in a simulation test of a tractor implement posture control system for hilly and mountainous areas provided by the present invention; Figure 7 This is the optimal fitness value curve in a simulation test of a tractor implement posture control system for hilly and mountainous areas provided by the present invention; Figure 8 This is an implement posture adjustment curve in a simulation test of a hilly and mountainous tractor implement posture control system provided by the present invention; The numbers in the figure are: 1-1, CPU module; 1-2, hydraulic valve control module; 1-3, actuator module; 1-4, sensor module; 1-5, early warning module; 2-1, right lifting arm; 2-2, right hydraulic cylinder; 2-3, left lifting arm; 2-4, right lifting rod; 2-5, upper pull rod; 2-6, right lower pull rod; 2-7, left hydraulic cylinder; 2-8, left lifting rod; 2-9, left lower pull rod. DETAILED DESCRIPTION

[0019] Specific Example 1: The technical solutions of the present invention will be described clearly and completely below with reference to the following examples. Obviously, the examples described are only some examples of the present invention, not all of them. Based on the examples of the present invention, all other examples obtained by persons of ordinary skill in the art without inventive effort are within the scope of protection of the present invention. It should be noted that, unless otherwise specified, all embodiments and preferred implementation methods described herein can be combined to form new technical solutions. Unless otherwise specified, all technical features and preferred features described herein can be combined to form new technical solutions. Unless otherwise specified, all components or preferred components described herein can be combined to form new technical solutions. "Range" disclosed herein, in the form of lower limits and upper limits, can refer to one or more lower limits and one or more upper limits, respectively. Unless otherwise specified, the reactions or steps described herein can be performed sequentially or in a sequential order. Preferably, the reaction methods described herein are performed sequentially. Unless otherwise specified, the technical and scientific terms used herein have the same meanings as those familiar to those skilled in the art. Furthermore, any methods or materials similar or equivalent to those described herein can also be applied to the present invention.

[0020] As the specification of the present invention Figure 1As shown, the present invention provides a hilly and mountainous tractor implement posture control system that can be used to adjust the posture of the working device of a hilly and mountainous wheeled tractor when working on a slope, thereby enabling the working device to always remain consistent with the changes in the slope angle, thereby improving the efficiency and stability of its slope operation; at the same time, the present invention can monitor the working status information of the working device, and issue an early warning when it detects that the vehicle body working device is out of synchronization or the working device has turned to an extreme angle, thereby ensuring the working safety of the tractor working device. The present invention provides a hilly mountain tractor agricultural implement posture control system mainly composed of a CPU module (1-1), a hydraulic valve control module (1-2), an actuator module (1-3), a sensor module (1-4), and an early warning module (1-5); wherein the CPU module (1-1) is used to convert, detect, filter, amplify, and perform other processing on the posture angle data signal output by the sensor module; the processed posture angle data signal is processed by a PSO-Fuzzy PID controller to generate an adjustment control signal and transmit it to the hydraulic valve control module (1-2); the electromagnetic reversing valve of the hydraulic valve control module (1-2) is connected in the forward or reverse direction to make the left and right hydraulic cylinders extend and retract; and the system is also used to process the hydraulic cylinder extension and retraction amount signal, whether the limit angle is reached, and the body working device angle difference signal, determine whether an alarm is required, and transmit its posture information, hydraulic cylinder extension and retraction amount information, etc. to the display screen of the early warning module (1-5); and is also used to process the electrical signal given by the reset key of the processor early warning module (1-5) and transmit the processed adjustment control signal to the hydraulic valve control module (1-2). The hydraulic proportional solenoid valve control block in the hydraulic valve control module (1-2) controls the solenoid valve to be connected in the forward or reverse direction for a certain period of time based on the adjustment signal, thereby controlling the extension and retraction of the hydraulic cylinder piston rod, thereby driving the actuator module (1-3) to adjust the posture of the agricultural implement. The actuator module includes left and right lift hydraulic cylinders (referred to as: left hydraulic cylinder 2-7 and right hydraulic cylinder 2-2), left and right lift arms (referred to as: left lift arm 2-3 and right lift arm 2-1), left and right lift rods (referred to as: left lift rod 2-8 and right lift rod 2-4), left and right lower tie rods (referred to as: left lower tie rod 2-9 and right lower tie rod 2-6), and an upper tie rod (2-5). The mechanical mechanism in the actuator module (1-3) is driven by the extension and retraction of the left and right hydraulic cylinders, driving the left and right lower tie rods to rise and fall, forming a height difference between the left and right lower tie rods, causing the working device to rotate relative to the vehicle body, thereby changing the lateral posture angle. The sensor modules (1-4) are used to detect the posture tilt angle of the tractor body and indirectly measure the slope angle, the posture tilt angle of the tractor working device, the extension and contraction amount of the working device hydraulic cylinder piston rod, and whether the working device has reached the limit tilt angle. At the same time, they generate posture angle data signals and extension and contraction displacement data signals, and transmit these data signals to the CPU module for data analysis and processing.The display screen in the warning module (1-4) displays the working device's posture information transmitted by the CPU module, including the angle between the vehicle body and the working device, and the extension and retraction of the hydraulic cylinder. A buzzer issues a warning of a misalignment between the vehicle body and the working device, or of reaching the maximum tilt angle. The driver can release the emergency stop state and restore the working device to its initial state by pressing the working device's home position button. This is a general overview of how the entire system functions.

[0021] This embodiment builds a system model based on the MATLAB / Simulink simulation platform to obtain inclination angle comparison curves for different posture adjustment control algorithms. PSO-Fuzzy PID control combines a particle swarm optimization algorithm, a fuzzy control system, and a PID control system in series to form a closed-loop agricultural implement posture adjustment control system. The deviation between the target inclination angle and the measured inclination angle, as well as the rate of change of the deviation, is processed by a fuzzy PID controller to obtain the corresponding parameter control variable. The particle swarm algorithm is used to optimize and adjust the PID parameters of the fuzzy PID controller. The steps for building a PSO-Fuzzy PID control working device posture adjustment simulation system are as follows: Step 1: Use MATLAB / Simulink to build a model and establish a particle swarm optimization simulation model based on the PSO-Fuzzy PID controller. Add the ITAE index part to the model, obtain it by time product and error absolute value integration, and set the output value S1 of output port 1 as the adaptive value of the particle swarm algorithm. Just add parameter symbols in the submodule. The model is named PSO-Fuzzy PID, and the specific graphics are as follows: Figure 5 As shown; Step 2: Design a fuzzy controller, setting the fuzzy input variables e (error), ec (error change rate), and the fuzzy output variables Kp, Ki, and Kd. The Mamdani reasoning method is used for fuzzy reasoning, and the area centroid method is used for clarification. The fuzzy language is set to PB (negative large), PM (negative medium), PS (negative small), ZO (zero), NS (positive small), NM (positive medium), and NB (positive large). Triangular functions are used for the membership functions of both the input and output quantities. Step 3: Use the m file to write the particle swarm optimization program and set the parameters. Set the particle swarm size to M, the number of iterations to N, and the maximum inertia weight to ω max , the minimum inertia weight is ω min , the individual acceleration constant is c1, the global acceleration constant is c2, the particle swarm dimension is D (that is, the number of optimized parameters), and the maximum particle speed is v max , the minimum particle speed is v min , the upper bound of particle displacement is Ub (i.e., the upper limit of each optimization parameter), and the lower bound of particle displacement is Lb (i.e., the lower limit of each optimization parameter); Step 4: Use the m-file to write the connection program. First, call the assignin function to assign the values ​​of X(1), X(2), and X(3) to Kp, Ki, and Kd in the Workspace. This statement transfers the parameters from the particle swarm algorithm to the Simulink component. Then, the parameters are sent to the model for simulation. Finally, the obtained performance indicator results are passed to the particle swarm module. The above is the specific process of setting up the entire simulation system.

[0022] The simulation operation process of the PSO-Fuzzy PID working device attitude adjustment is as follows: S1: Set the simulation tilt angle to 12°, and use fuzzy PID and PSO-Fuzzy PID to simulate and compare the working device posture adjustment system. Set the basic parameters of the particle swarm optimization program, set the maximum inertia weight to 0.9, the minimum inertia weight to 0.4, the individual acceleration constant to 2, the global acceleration constant to 2, the particle swarm dimension to 3, the maximum particle speed to 1, the minimum particle speed to -1, the particle displacement upper bound Ub to [600 100 200], and the particle displacement lower bound Lb to [300 0 0]. S2: Initialize the particle swarm, set the number of iterations to 50, confirm the number of particle swarms, each particle represents a set of PID parameters, and the number of particle swarms is 50; S3: Tuning PID parameters. The fuzzy controller selects two inputs and three outputs. The input values ​​are the inclination deviation value e(t) and the deviation change rate ec. The output values ​​are the proportional gain deviation value ΔKp, the integral gain deviation value ΔKi, and the differential gain deviation value ΔKd. The final output PID parameter value is realized by the following formula:

[0023] Where Kp, Ki, and Kd are the parameter values ​​after fuzzy control tuning, Kp', Ki', and Kd' are the initial parameter values ​​of the PID controller, and ΔKp, ΔKi, and ΔKd are the parameter deviation values ​​of fuzzy control tuning; S4: Initialize the random position and velocity of the particle swarm, and randomly generate the velocity vi and position xi of each particle; S5: Evaluate the fitness. Use the integral index of the product of time and absolute error to optimize the parameters of the PID controller for adjusting the posture of the working device. The fitness function is:

[0024] S6: Update particle speed and position. Update the particle speed and position according to the fitness value using the following formula: Velocity update formula:

[0025] Position update formula:

[0026] S7: Update the historical optimal position. If the fitness of the current particle is better than its historical optimal fitness, update its historical optimal position Pi. At the same time, check and update the global optimal position Pg. S8: Output the optimal solution. When the particle swarm reaches the minimum fitness or the iteration ends, the global optimal position Pg[A, B, C] is assigned to the PID parameters to obtain Kp best 、Ki best 、Kd best .

[0027] In this example, the simulation inclination angle is set to 12°, the number of particle swarm optimization iterations is 50, and the particle swarm size is 50. By running the simulation model and after multiple iterations of the particle swarm, the optimal PID parameters are finally obtained; PID controller parameter optimization curve is as shown in the instruction manual. Figure 6 As shown in the figure, the optimal solution is Kp=487.47, Ki=0, Kd=58.41. The curve of the optimal fitness value changing with the number of iterations is shown in the appendix of the manual. Figure 7 As shown, the final stable fitness value is 0.18858; The simulation tracking response of the PSO-Fuzzy PID control algorithm to the step signal is shown in the attached manual. Figure 8 As shown in the step response curve of the particle swarm PID control simulation, the attitude adjustment time of the working device is 1.19s, and the overshoot is 0.06°, which is almost negligible. It can be seen that under the particle swarm PID control with adjusted parameters, the attitude adjustment time is short, the response is fast, and the dynamic performance of the system is good. After waveform analysis and calculation, Table 1 shows the performance comparison of the specific step response between the two.

[0028] Comparative analysis shows that the PSO-Fuzzy PID control algorithm better meets the posture adjustment requirements of tractor operating devices in hilly and mountainous areas than traditional PID control algorithms. The above description is merely a preferred embodiment of the present invention and does not constitute any formal limitation on the present invention. Although the present invention has been disclosed above in terms of preferred embodiments, this is not intended to limit the present invention. Any person skilled in the art can utilize the above-disclosed technical content to make minor changes or modifications to equivalent embodiments without departing from the scope of the present invention. However, any simple modifications, equivalent changes, and modifications made to the above embodiments based on the technical essence of the present invention without departing from the scope of the present invention remain within the scope of the present invention.

Claims

1. A hilly mountain tractor agricultural implement posture control system, characterized in that: Including CPU module, hydraulic valve control module, actuator module, sensor module, and early warning module; The CPU module includes a particle swarm fuzzy PID control unit and a limit information processing unit; The hydraulic valve control module includes a hydraulic oil tank, a filter, a hydraulic oil pump, a relief valve, an electromagnetic proportional valve, and a one-way throttle valve; The actuator module includes left and right lifting hydraulic cylinders, left and right lifting arms, left and right lifting rods, left and right lower pull rods, and upper pull rods; The sensor module includes a hydraulic cylinder displacement sensor, a vehicle body attitude lateral attitude inclination sensor and a working device attitude lateral attitude inclination sensor; The early warning module includes a display screen, a buzzer, and a reset button; The sensor module can monitor various posture information, generate electrical signals and input them into the CPU module. The CPU module processes the electrical signals and generates adjustment signals through the PSO-Fuzzy PID control algorithm. After receiving the adjustment signal, the hydraulic valve control module controls the flow size and direction of the hydraulic oil circuit by controlling the current size of the input electromagnetic proportional valve, and finally controls the extension and retraction of the left and right lifting hydraulic cylinders. The actuator module drives the movement of the adjustment mechanism through the extension and retraction of the left and right lifting hydraulic cylinders on both sides, and forms a height difference through the movement of the adjustment mechanisms on both sides, so as to adjust the lateral inclination angle of the working device. After receiving the posture and warning information electrical signals, the early warning module displays the posture information such as the inclination angle of the tractor body, the inclination angle of the working device, the extension and retraction displacement of the hydraulic cylinder, etc. on the display screen, and can issue an abnormal alarm through the buzzer.

2. The hilly mountain tractor agricultural implement posture control system according to claim 1, characterized in that: The CPU module is used to convert, detect, filter and amplify the attitude data signal output by the sensor module. The processed attitude angle data signal calculates the hydraulic cylinder piston rod extension and contraction required for attitude adjustment in real time and further processes it through the PSO-Fuzzy PID control algorithm to obtain the current size of the electromagnetic reversing valve in the forward or reverse direction, and generates an adjustment control signal to be transmitted to the valve-controlled hydraulic module.

3. The hilly mountain tractor agricultural implement posture control system according to claim 2, characterized in that: The CPU module is used to process the lateral inclination angle signal of the vehicle body, the lateral inclination angle signal of the agricultural implement, and the hydraulic cylinder displacement signal to determine whether they are within the set safety range. If they are beyond the safety range, the posture and warning information processing unit will send an alarm signal to the warning module, causing the warning module to issue an alarm; at the same time, the posture information and the hydraulic cylinder extension and contraction amount information are transmitted to the display screen of the warning module; the CPU module can receive the reset signal given by the warning module and process it, and transfer the processed adjustment control signal to the hydraulic valve control module.

4. The hilly mountain tractor agricultural implement posture control system according to claim 1, characterized in that: The solenoid valve in the hydraulic valve control module adopts a three-position four-way solenoid valve. The hydraulic valve control module controls the direction and opening size of the solenoid valve core movement according to the adjustment electrical signal, and then controls the flow size and direction of the hydraulic oil in the hydraulic circuit, thereby controlling the telescopic displacement of the hydraulic cylinder.

5. The hilly mountain tractor agricultural implement posture control system according to claim 4, characterized in that: The upper pull rod and the left and right lower pull rods in the actuator module are connected to the working device through a ball pin; the tail of the hydraulic rod of the left and right lifting hydraulic cylinders on both sides of the actuator module is connected to the lifting arm by a pin shaft, the lifting arm and the lifting rod are connected by a ball pin, and the lifting rod and the lower pull rod are connected by a pin shaft; the telescopic movement of the hydraulic cylinder is transmitted to the linkage mechanism of the actuator, and finally transmitted to the left and right lower pull rods, so that the left and right lower pull rods form a height difference, thereby changing the posture inclination angle of the working device.

6. The hilly mountain tractor agricultural implement posture control system according to claim 5, characterized in that: The sensor module is used to detect the posture inclination angle of the tractor body in hilly and mountainous areas and indirectly measure the slope angle, the posture inclination angle of the working device, and the extension and retraction amount of the hydraulic cylinder piston rod of the working device, while generating posture angle data signals and extension and retraction displacement data signals, and transmitting the detection data signals to the posture and warning information processing unit in the CPU module for data analysis and processing.

7. The hilly mountain tractor agricultural implement posture control system according to claim 6, characterized in that: The display screen in the early warning module can display the working device posture information transmitted by the CPU module. The working device posture information includes the angle of the vehicle body and the working device, and the extension and retraction amount of the hydraulic cylinder; when each posture data exceeds the set safety range, the buzzer will sound an alarm and the entire posture adjustment system will stop urgently; after an emergency stop occurs, the driver can operate the reset button in the early warning module after checking and clearing the fault to restore the working device to its initial state.

8. The hilly mountain tractor agricultural implement posture control system according to claim 1, characterized in that: The particle swarm fuzzy PID control unit is used to control the posture adjustment of the working device through a particle swarm optimization fuzzy PID control algorithm (PSO-Fuzzy PID); the algorithm optimization process of the particle swarm fuzzy PID controller is to optimize the parameters in the fuzzy control; for the problem of posture adjustment control of the working device, the particle swarm optimization algorithm optimizes the three PID control parameters of the fuzzy output Kp, Ki and Kd of the fuzzy controller; the particle swarm fuzzy PID controller optimizes the current fuzzy control quantities Kp, Ki, and Kd, and obtains the global optimal PID parameters Kpbest, Kibest, and Kdbest of the current particle swarm through particles, and feeds back the global optimal parameters Kpbest, Kibest, and Kdbest to the hydraulic valve control module, and drives the actuator to perform telescopic displacement of the hydraulic cylinder to adjust the posture inclination angle of the working device, thereby realizing the posture control of the working device.

9. The hilly mountain tractor implement posture control system according to claim 8, characterized in that: The particle swarm fuzzy PID control unit optimizes the current fuzzy control quantities Kp, Ki, and Kd, specifically comprising the following steps: Step 1, set the fuzzy controller: set the fuzzy input variables e (error), ec (error change rate) and fuzzy output variables Kp, Ki, Kd; select Mamdani reasoning method for fuzzy reasoning, and use the area centroid method for clarification; set the fuzzy language to PB (negative large), PM (negative medium), PS (negative small), ZO (zero), NS (positive small), NM (positive medium), NB (positive large). The membership functions of both input and output quantities use triangular functions; Step 2, initialize the particle swarm: initially set the random position and speed of the particle swarm; given the population size M and spatial dimension N, randomly generate the speed vi and position xi of each particle; Step 3, fitness evaluation: The fitness of the particles is calculated according to the fitness function in the algorithm, and the current fitness value f(xi) of each particle is calculated using the benchmark test function f(x); the control system uses the integral index of the product of time and absolute error to optimize the parameters of the fuzzy PID controller for attitude adjustment of the operating device; it can fully reflect the relationship between the deviation and time of the system; the smaller the value, the better, and the expression can be described as: ; Step 4. Update particle speed and position: Update the particle speed and position according to the fitness value, using the following formula: Speed ​​update formula: ; Position update formula: ; At the same time, make sure that the particle position (PID parameters) is still within the preset range; Step 5, Update the historical optimal position: If the fitness of the current particle is better than its historical optimal fitness, update its historical optimal position Pi; at the same time, check and update the global optimal position Pg; Step 6. Determine the termination condition: Check whether the termination condition is met, such as reaching the maximum number of iterations or the fitness reaching the preset threshold; Step 7. Output results: Output the fuzzy output variables Kpbest, Kibest, and Kdbest corresponding to the global optimal position, and input them into the PID controller as the optimization results to control the posture adjustment device.

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