A dynamic monitoring and stability control system and control method for tillage depth

Abstract

This invention provides a dynamic monitoring and stability control system and method for tillage depth. The system monitors the operating status of the tractor and rotary tiller using a speed-measuring radar fixed to the tractor, a tilt attitude sensor, and a stroke sensor mounted on the second lifting hydraulic cylinder. The operational stability of the rotary tiller is controlled via an oil tank, a hydraulic pump, a three-position six-way proportional multi-way valve (first section), a first one-way valve, a second one-way valve, a third one-way valve, a first speed control valve, a fourth one-way valve, a fifth one-way valve, a sixth one-way valve, a seventh one-way valve, a second speed control valve, an eighth one-way valve, a three-position six-way proportional multi-way valve (second section), and a third speed control valve. Combined with the dynamic monitoring and stability control method for tillage depth, the system can monitor the tractor's tillage depth online. When no actuators are working, the system is unloaded, resulting in low heat generation. The two lifting hydraulic cylinders have high synchronization accuracy, effectively ensuring the quality requirements of the operation.

Description

Technical Field

[0001] This invention relates to the field of agricultural planting technology, specifically to a dynamic monitoring and stability control system and method for tillage depth. Background Technology

[0002] Tillage is one of the important links in agricultural production. Tillage is beneficial to improving the physical properties of soil and regulating the ratio of solid, liquid and gas phases in the soil. Tillage depth is one of the important evaluation indicators of the operation quality of tillage machinery. According to relevant standards in my country, the stability of tillage depth should be ≥85%. At the same time, with the continuous development of precision agriculture, the accuracy of judging tillage depth by only monitoring the position of the hydraulic cylinder of the three-point suspension of the tractor is no longer sufficient to meet the production needs. The main problems are as follows: (1) It does not have the function of online monitoring of tillage depth and cannot obtain tillage depth data in real time; (2) The hydraulic system with solenoid valve as the control element generates a lot of heat and the system impact is large. Summary of the Invention

[0003] The purpose of this invention is to provide a dynamic monitoring and stability control system and method for tillage depth, which can monitor the tillage depth of the tractor online in real time, unload the system when no actuators are working, generate low heat in the hydraulic system, and ensure high synchronization accuracy of the two lifting hydraulic cylinders to guarantee the quality requirements of the operation.

[0004] To achieve the above objectives, the present invention adopts the following technical solution:

[0005] A dynamic monitoring and stability control system for tillage depth includes a tillage depth monitoring unit, a stability control unit, a first lifting hydraulic cylinder, and a second lifting hydraulic cylinder. The tillage depth monitoring unit includes a controller, a speed measuring radar, and a tilt angle attitude sensor fixed to a tractor. The first lifting hydraulic cylinder, the second lifting hydraulic cylinder, the tilt angle attitude sensor, and the speed measuring radar are fixed to the tractor. The tractor is connected to a rotary tiller via a suspension lowering rod. The piston rods of the first and second lifting hydraulic cylinders extend upward and are hinged to the bottom of the suspension lowering rod. A stroke sensor is installed on the second lifting hydraulic cylinder. Hydraulic actuators are installed on the tractor.

[0006] The stability control unit includes an oil tank, a hydraulic pump, a three-position six-way proportional multi-way valve (first section), a first check valve, a second check valve, a third check valve, a first speed control valve, a fourth check valve, a fifth check valve, a sixth check valve, a seventh check valve, a second speed control valve, an eighth check valve, a three-position six-way proportional multi-way valve (second section), and a third speed control valve.

[0007] The hydraulic pump is connected to the tractor's engine drive; the P and F ports of the first section of the three-position six-way proportional multi-way valve and the P port of the second section of the three-position six-way proportional multi-way valve are connected to the hydraulic pump's outlet; the A port of the second section of the three-position six-way proportional multi-way valve is connected to the rodless chamber of the hydraulic actuator, the B port is connected to the rod chamber of the hydraulic actuator, and the F port is connected to the E port of the first section of the three-position six-way proportional multi-way valve; the inlet port of the first check valve, the outlet port of the second check valve, the inlet port of the fourth check valve, and the outlet port of the fifth check valve are connected to the A port of the first section of the three-position six-way proportional multi-way valve; the outlet ports of the first and third check valves are connected to the A port of the first speed control valve; the inlet ports of the second and eighth check valves are connected to the B port of the first speed control valve; the inlet ports of the third and eighth check valves are connected to the... The oil outlet of the first lifting hydraulic cylinder is connected to the rodless chamber of the first lifting hydraulic cylinder; the oil outlets of the fourth and seventh check valves are connected to the A port of the second speed control valve; the oil inlets of the fifth and sixth check valves are connected to the B port of the second speed control valve; the oil outlets of the sixth and seventh check valves are connected to the rodless chamber of the second lifting hydraulic cylinder; the rod chambers of the first and second lifting hydraulic cylinders are connected to the B port of the first section of the three-position six-way proportional multi-way valve; the oil inlet of the hydraulic pump, the E port of the second section of the three-position six-way proportional multi-way valve, the T port of the first section of the three-position six-way proportional multi-way valve, and the T port of the second section of the three-position six-way proportional multi-way valve are connected to the oil tank; the openings of the first and second speed control valves are the same; the speed measuring radar, tilt attitude sensor, and stroke sensor are electrically connected to the controller.

[0008] Preferably, it further includes a filtration unit; the filtration unit includes a spring-loaded check valve and a filter; the T-port of the first section of the three-position six-way proportional multi-way valve and the T-port of the second section of the three-position six-way proportional multi-way valve are connected to the oil inlet of the spring-loaded check valve, and the oil outlet of the spring-loaded check valve is connected to the oil tank; both ends of the filter are connected to the oil inlet and oil outlet of the spring-loaded check valve, respectively.

[0009] Preferably, it further includes a cooling unit; the cooling unit includes a hydraulic oil temperature sensor, a cooler, a third speed control valve, and a shut-off valve; the outlet pipe of the spring-loaded check valve and the filter passes through the cooler and is connected to the oil tank; the hydraulic oil temperature sensor is connected to the oil tank; the A port of the third speed control valve is connected to the shut-off valve, and the B port is connected to the inlet of the cooler.

[0010] Preferably, it further includes a safety valve; the oil inlet of the safety valve is connected to the oil outlet of the hydraulic pump, and the oil outlet is connected to the oil tank.

[0011] Preferably, it also includes a pressure sensor and a proportional relief valve; the T-port of the first section of the three-position six-way proportional multi-way valve and the T-port of the second section of the three-position six-way proportional multi-way valve are connected to the oil inlet of the proportional relief valve; the oil outlet of the proportional relief valve is connected to the oil inlet of the spring-loaded check valve; the pressure sensor is connected to the oil inlet pipeline of the proportional relief valve.

[0012] A method for dynamic monitoring and stability control of tillage depth includes:

[0013] S1, Tillage Depth Monitoring Method

[0014] The working depth of the rotary tiller can be calculated using Formula 1:

[0015] (1)

[0016] In the formula, This refers to the working depth of the rotary tiller. The diameter of rotation of the rotary tiller. The length of the tractor suspension lower control arm. The angle between the tractor's suspension lower control rod and the horizontal direction. The vertical distance from the fixing point of the suspension lower rod to the ground;

[0017] Solving the problem through experimental testing and linear fitting. , and Relationship:

[0018] (2)

[0019] The regulations specify the pitch angle when the tractor is in an upward tilt position. The pitch angle is a positive value when the tractor is in a downward-facing position. It is a negative value;

[0020] Substituting Formula 2 into Formula 1, we get

[0021] (3)

[0022] For the selected tractor and rotary tiller, , and All are constant values. , , , , , These are parameters to be determined and need to be identified through experimental testing and linear fitting. The stroke of the piston rod of the second lifting hydraulic cylinder is measured in real time by a stroke sensor. Acquired in real time through tilt attitude sensor;

[0023] S2, Stability Control Method

[0024] The speed measuring radar uses real-time dynamic carrier phase differential technology to monitor the tractor's operating speed in real time. When the tractor's operating speed is relatively fast, the first and second lifting hydraulic cylinders are controlled to speed up their actions; conversely, the first and second lifting hydraulic cylinders are controlled to slow down their actions.

[0025] Preferably, when solving for the undetermined parameters, the tractor is parked on a tilting adjustable lifting platform and adjusted to... ≥0, the stroke of the first lifting hydraulic cylinder and the second lifting hydraulic cylinder Fixed in a certain position, assuming The range of values ​​for ≥0 is (0, ... max1 If the angle is adjusted via a lifting platform, the angle change increment is 0.1. max1 Record the swing angle of the suspension lower lever at different tilt angles in sequence. The value can then be obtained through linear fitting. , The parameter value; similarly, park the tractor on the tilt-adjustable lifting platform and adjust it to... <0, the stroke of the first lifting hydraulic cylinder and the second lifting hydraulic cylinder Fixed in a certain position, assuming The range of values ​​for <0 is (— max2 If the value is 0, then the angle is adjusted by the lifting platform, with the angle change step being 0.1. max2 Record the swing angle of the suspension lower lever at different tilt angles in sequence. The value can then be obtained through linear fitting. , The value of the parameter;

[0026] Meanwhile, the tractor is parked on level ground. Assuming the strokes of the first and second lifting hydraulic cylinders are... The range of values ​​for is (0, ...). -max Then, by adjusting the stroke of the first and second lifting hydraulic cylinders, the stroke variation step is 0.1. -max Record the suspension pull rod swing angle under different strokes in sequence. The value can then be obtained through linear fitting. The value of the parameter.

[0027] Compared with the prior art, the beneficial effects of the present invention are as follows:

[0028] (1) The operating status of the tractor and rotary tiller is monitored by the speed measuring radar, tilt attitude sensor and stroke sensor set on the second lifting hydraulic cylinder, which are fixed on the tractor. The online monitoring of the tractor's tillage depth can be realized. The model parameters are easy to obtain, the versatility is strong, and the monitoring accuracy is high. (2) The three-position six-way proportional multi-way valve configured in the system is unloaded when no actuator is working, so that the system generates less heat. (3) The shuttle valve bidirectional speed regulation circuit ensures that the two lifting hydraulic cylinders have high synchronization accuracy in both directions, effectively guaranteeing the quality requirements of the operation. Attached Figure Description

[0029] Figure 1 This is a schematic diagram of the structure of the present invention;

[0030] Figure 2 This is a hydraulic schematic diagram of the present invention;

[0031] Figure 3 This is a flowchart of the control method in this invention.

[0032] In the picture:

[0033] 1. Oil tank; 2. Hydraulic pump; 3. Safety valve; 4. First port of a 3-position 6-way proportional multi-way valve; 5. First check valve; 6. Second check valve; 7-1. First lifting hydraulic cylinder; 7-2. Second lifting hydraulic cylinder; 8. Third check valve; 9. First speed control valve; 10. Fourth check valve; 11. Fifth check valve; 12. Sixth check valve; 13. Seventh check valve; 14. Second speed control valve; 15. Eighth check valve; 16. Stroke sensor; 17. Second port of a 3-position 6-way proportional multi-way valve; 18. Hydraulic actuator; 19. Proportional relief valve; 20. Spring-loaded check valve; 21. Hydraulic oil temperature sensor; 22. Filter; 23. Cooler; 24. Third speed control valve; 25. Shut-off valve; 26. Pressure sensor; 27. Tractor; 28. Tilt attitude sensor; 29. ​​Rotary tiller; 30. Suspension lower control rod; 31. Speed ​​measuring radar. Detailed Implementation

[0034] The invention will now be further described with reference to the accompanying drawings.

[0035] like Figure 1 , Figure 2As shown, a tillage depth dynamic monitoring and stability control system includes a tillage depth monitoring unit, a stability control unit, a first lifting hydraulic cylinder 7-1, and a second lifting hydraulic cylinder 7-2. The tillage depth monitoring unit includes a controller fixed on a tractor 27, a speed measuring radar 31, and a tilt angle attitude sensor 28. The first lifting hydraulic cylinder 7-1, the second lifting hydraulic cylinder 7-2, the tilt angle attitude sensor 28, and the speed measuring radar 31 are fixed on the tractor 27. The tractor 27 is connected to a rotary tiller 29 via a suspension lowering rod 30. The piston rods of the first lifting hydraulic cylinder 7-1 and the second lifting hydraulic cylinder 7-2 extend upward and are hinged to the bottom of the suspension lowering rod 30. A stroke sensor 16 is provided on the second lifting hydraulic cylinder 7-2. A hydraulic actuator 18 is provided on the tractor 27, and the hydraulic actuator 18 is the actuator for other working parts on the tractor 27.

[0036] The stability control unit includes an oil tank 1, a hydraulic pump 2, a three-position six-way proportional multi-way valve (first section) 4, a first check valve 5, a second check valve 6, a third check valve 8, a first speed control valve 9, a fourth check valve 10, a fifth check valve 11, a sixth check valve 12, a seventh check valve 13, a second speed control valve 14, an eighth check valve 15, a three-position six-way proportional multi-way valve (second section) 17, and a third speed control valve 24.

[0037] Hydraulic pump 2 is connected to the engine drive of tractor 27; the P port and F port of the first section 4 of the three-position six-way proportional multi-way valve, and the P port of the second section 17 of the three-position six-way proportional multi-way valve are connected to the oil outlet of hydraulic pump 2; the A port of the second section 17 of the three-position six-way proportional multi-way valve is connected to the rodless chamber of hydraulic actuator 18, the B port is connected to the rod chamber of hydraulic actuator 18, and the F port is connected to the E port of the first section 4 of the three-position six-way proportional multi-way valve; the oil inlet of the first check valve 5... The oil outlet of the first check valve 6, the oil inlet of the fourth check valve 10, and the oil outlet of the fifth check valve 11 are connected to port A of the first three-position six-way proportional multi-way valve 4; the oil outlet of the first check valve 5 and the oil outlet of the third check valve 8 are connected to port A of the first speed control valve 9; the oil inlet of the second check valve 6 and the oil inlet of the eighth check valve 15 are connected to port B of the first speed control valve 9; the oil inlet of the third check valve 8 and the oil outlet of the eighth check valve 15 are connected to port A of the first speed control valve 9. The rodless chamber of the lifting hydraulic cylinder 7-1 is connected; the oil outlet of the fourth check valve 10 and the oil outlet of the seventh check valve 13 are connected to the A port of the second speed regulating valve 14; the oil inlet of the fifth check valve 11 and the oil inlet of the sixth check valve 12 are connected to the B port of the second speed regulating valve 14; the oil outlet of the sixth check valve 12 and the oil inlet of the seventh check valve 13 are connected to the rodless chamber of the second lifting hydraulic cylinder 7-2; the rod chamber of the first lifting hydraulic cylinder 7-1 and the second lifting hydraulic cylinder 7-2 are connected to the rodless chamber of the first lifting hydraulic cylinder 7-1 and the rodless chamber of ... first lifting hydraulic cylinder 7-2 are connected to the rodless chamber of the first lifting hydraulic cylinder 7-1 and the rodless chamber of the second lifting hydraulic cylinder 7 The rod chamber of cylinder 7-2 is connected to port B of the first section 4 of the three-position six-way proportional multi-way valve; the oil inlet of hydraulic pump 2, port E of the second section 17 of the three-position six-way proportional multi-way valve, port T of the first section 4 of the three-position six-way proportional multi-way valve, and port T of the second section 17 of the three-position six-way proportional multi-way valve are connected to oil tank 1; the openings of the first speed control valve 9 and the second speed control valve 14 are the same; the speed measuring radar 31, the tilt attitude sensor 28, and the stroke sensor 16 are electrically connected to the controller respectively;

[0038] When the first lifting hydraulic cylinder 7-1, the second lifting hydraulic cylinder 7-2, and the hydraulic actuator 18 are not working, the hydraulic oil output by the hydraulic pump 2 flows back to the oil tank 1 through the F and E ports of the first three-position six-way proportional multi-way valve 4 and the F and E ports of the second three-position six-way proportional multi-way valve 17, unloading the system. When one or more of the first lifting hydraulic cylinder 7-1, the second lifting hydraulic cylinder 7-2, and the hydraulic actuator 18 are working (when the first three-position six-way proportional multi-way valve 4 or the second three-position six-way proportional multi-way valve 17 is not in the neutral position), the system can establish pressure for operation. It can connect to N connections of the second three-position six-way proportional multi-way valve 17 (generally N is less than 10), thus driving multiple sets of hydraulic actuators 18.

[0039] The first check valve 5, the second check valve 6, the third check valve 8, the eighth check valve 15, and the first speed regulating valve 9 form a shuttle valve bidirectional speed regulating circuit. The fourth check valve 10, the fifth check valve 11, the sixth check valve 12, the seventh check valve 13, and the second speed regulating valve 14 form another shuttle valve bidirectional speed regulating circuit. The oil in the first speed regulating valve 9 and the second speed regulating valve 14 can only flow from port A to port B. Both the first lifting hydraulic cylinder 7-1 and the second lifting hydraulic cylinder 7-2 are hydraulic cylinders of the tractor's 27 hydraulic suspension. The two hydraulic cylinders are required to have a certain synchronization accuracy, so the opening degree (flow rate of hydraulic oil) of the first speed regulating valve 9 and the second speed regulating valve 14 is always the same.

[0040] When the first link 4 of the three-position six-way proportional multi-way valve is switched to the left position, one hydraulic oil output from the hydraulic pump 2 flows sequentially through the P and A ports of the first link 4 of the three-position six-way proportional multi-way valve, the first check valve 5, the A and B ports of the first speed control valve 9, the eighth check valve 15, and the rodless chamber of the first lifting hydraulic cylinder 7-1. Then, the hydraulic oil in the rod chamber of the first lifting hydraulic cylinder 7-1 flows through the B and T ports of the first link 4 of the three-position six-way proportional multi-way valve. The other hydraulic oil flows sequentially through the P and A ports of the first link 4 of the three-position six-way proportional multi-way valve, the fourth check valve 10, the A and B ports of the second speed control valve 14, the sixth check valve 12, and the rodless chamber of the second lifting hydraulic cylinder 7-2. Then, the hydraulic oil in the rod chamber of the second lifting hydraulic cylinder 7-2 flows through the B and T ports of the first link 4 of the three-position six-way proportional multi-way valve.

[0041] When the first link 4 of the three-position six-way proportional multi-way valve is switched to the right position, one hydraulic oil output from the hydraulic pump 2 passes sequentially through the P and B ports of the first link 4 of the three-position six-way proportional multi-way valve, the rod chamber of the first lifting hydraulic cylinder 7-1, and then the hydraulic oil in the rodless chamber of the first lifting hydraulic cylinder 7-1 flows through the third check valve 8, the A and B ports of the first speed control valve 9, the second check valve 6, and the A and T ports of the first link 4 of the three-position six-way proportional multi-way valve; the other hydraulic oil passes sequentially through the P and B ports of the first link 4 of the three-position six-way proportional multi-way valve, the rod chamber of the second lifting hydraulic cylinder 7-2, and then the hydraulic oil in the rodless chamber of the second lifting hydraulic cylinder 7-2 flows through the seventh check valve 13, the A and B ports of the second speed control valve 14, the fifth check valve 11, and the A and T ports of the first link 4 of the three-position six-way proportional multi-way valve.

[0042] Furthermore, a filter unit is provided to remove impurities from the hydraulic oil. The filter unit includes a spring-loaded check valve 20 and a filter 22. The T-port of the first section 4 of the three-position six-way proportional multi-way valve and the T-port of the second section 17 of the three-position six-way proportional multi-way valve are connected to the oil inlet of the spring-loaded check valve 20, and the oil outlet of the spring-loaded check valve 20 is connected to the oil tank 1. The two ends of the filter 22 are connected to the oil inlet and oil outlet of the spring-loaded check valve 20, respectively. When the filter 22 is not blocked, the hydraulic oil flows through the filter 22. When the filter 22 is blocked, the hydraulic oil flows through the spring-loaded check valve 20, and the opening pressure of the spring-loaded check valve 20 is 10 bar.

[0043] Furthermore, to reduce the temperature of the circulating hydraulic oil in the system, a cooling unit is also provided. The cooling unit includes a hydraulic oil temperature sensor 21, a cooler 23, a third speed control valve 24, and a shut-off valve 25. The outlet pipes of the spring-loaded check valve 20 and the filter 22 pass through the cooler 23 and are connected to the oil tank 1. The hydraulic oil temperature sensor 21 is connected to the oil tank 1. Port A of the third speed control valve 24 is connected to the shut-off valve 25, and port B is connected to the inlet of the cooler 23. When the hydraulic temperature sensor 21 detects that the hydraulic oil temperature exceeds a certain set value set by the controller, the shut-off valve 25 opens. The third speed control valve 24 determines the cooling capacity of the system. When the oil temperature rises rapidly, the opening degree of the third speed control valve 24 is larger, and vice versa.

[0044] Furthermore, it also includes a safety valve 3; the oil inlet of the safety valve 3 is connected to the oil outlet of the hydraulic pump 2, and the oil outlet is connected to the oil tank 1; the safety valve 3 is used to set the safety pressure of the system, and when the outlet pressure of the hydraulic pump 2 exceeds the set safety pressure, the safety valve 3 opens to unload.

[0045] Furthermore, to monitor whether filter 22 is clogged and needs replacement, a pressure sensor 26 and a proportional relief valve 19 are also included. The T port of the first section 4 of the three-position six-way proportional multi-way valve and the T port of the second section 17 of the three-position six-way proportional multi-way valve are connected to the oil inlet of the proportional relief valve 19. The oil outlet of the proportional relief valve 19 is connected to the oil inlet of the spring-loaded check valve 20. The pressure sensor 26 is connected to the oil inlet pipeline of the proportional relief valve 19. The proportional relief valve 19 is used to steplessly set the system back pressure, and its set pressure is between 3-10 bar. The value of the pressure sensor 26 is monitored to determine whether filter 22 needs to be replaced. When the test pressure of the pressure sensor 26 is significantly greater than the set pressure of the proportional relief valve 19, it indicates that filter 22 is clogged and needs to be replaced.

[0046] like Figure 3 As shown, a method for dynamic monitoring and stability control of tillage depth includes:

[0047] Tillage depth can be calculated using Formula 1:

[0048] (1)

[0049] In the formula, This refers to the working depth of the rotary tiller 29. The rotation diameter of rotary tiller 29, The length of the tractor 27 suspension lower control rod 30 is given. The angle between the tractor 27 suspension lower control rod 30 and the horizontal direction (positive for upward and negative for downward). This refers to the vertical distance from the fixing point of the suspension lower lever 30 to the ground. The rotation diameter of the rotary tiller 29, the length of the suspension lower lever 30 of the tractor 27, and the vertical distance from the fixing point of the suspension lower lever 30 to the ground can be obtained by measuring with a tape measure.

[0050] For the selected tractor 27 and rotary tiller 29, , and All values ​​are constants; the actual tillage depth is 30 degrees of swing angle from the suspension lower lever. The function, while the suspension lower lever has a 30° swing angle. It is the tractor's 27-degree tilt angle. The stroke of the first lifting hydraulic cylinder 7-1 and the second lifting hydraulic cylinder 7-2 The function.

[0051] The solution can be obtained through experimental testing and linear fitting. , and Relationship:

[0052] (2)

[0053] The specification stipulates that when the tractor 27 is in an upward tilting posture, the pitch angle is... The value is positive; when the tractor 27 is in a downward-facing posture, the pitch angle is... It is a negative value.

[0054] When solving for the undetermined parameters, tractor 27 is parked on the tilt-adjustable lifting platform and adjusted to... ≥0, the stroke of the first lifting hydraulic cylinder 7-1 and the second lifting hydraulic cylinder 7-2 is reduced. Fixed in a certain position, assuming The range of values ​​for ≥0 is (0, ... max1 If the angle is adjusted via a lifting platform, the angle change increment is 0.1. max1 Record the 30° swing angle of the suspension lower lever under different tilt angles in sequence. The value can then be obtained through linear fitting. , The parameter value. Similarly, park tractor 27 on the tilt-adjustable lifting platform and adjust it to... <0, the stroke of the first lifting hydraulic cylinder 7-1 and the second lifting hydraulic cylinder 7-2 is reduced. Fixed in a certain position, assuming The range of values ​​for <0 is (— max2 If the value is 0, then the angle is adjusted by the lifting platform, with the angle change step being 0.1. max2 Record the 30° swing angle of the suspension lower lever under different tilt angles in sequence. The value can then be obtained through linear fitting. , The value of the parameter.

[0055] Meanwhile, the tractor 27 is parked on level ground. Assuming the strokes of the first lifting hydraulic cylinder 7-1 and the second lifting hydraulic cylinder 7-2 are... The range of values ​​for is (0, ...). -max Then, by adjusting the stroke of the first lifting hydraulic cylinder 7-1 and the second lifting hydraulic cylinder 7-2, the stroke variation step is 0.1. -max Record the 30° swing angle of the suspension lower lever under different strokes of the first lifting hydraulic cylinder 7-1 and the second lifting hydraulic cylinder 7-2. The value can then be obtained through linear fitting. The value of the parameter. Wherein, = Substituting Formula 2 into Formula 1, we get...

[0056] (3)

[0057] For the selected tractor 27 and rotary tiller 29, , and All are constant values. , , , , , These are parameters to be determined and need to be identified through experimental testing and linear fitting. The stroke of the piston rod of the second lifting hydraulic cylinder 7-2 is measured in real time by the stroke sensor 16. The speed is measured in real time by the tilt attitude sensor 28. The speed measuring radar 31 uses real-time dynamic carrier phase differential technology to monitor the working speed of the tractor 27 in real time. When the working speed of the tractor 27 is relatively fast, the first lifting hydraulic cylinder 7-1 and the second lifting hydraulic cylinder 7-2 are required to act quickly (high sensitivity). Conversely, the first lifting hydraulic cylinder 7-1 and the second lifting hydraulic cylinder 7-2 are required to act slowly (low sensitivity).

Claims

1. A method for dynamic monitoring and stability control of tillage depth, characterized in that, include: S1, Tillage Depth Monitoring Method The working depth of the rotary tiller can be calculated using Formula 1: （1） In the formula, The working depth of the rotary tiller (29), The rotation diameter of the rotary tiller (29) The length of the lower suspension rod (30) of the tractor (27), The angle between the tractor (27) suspension lower lever (30) and the horizontal direction, The vertical distance from the fixing point of the suspension lower lever (30) to the ground; Solving the problem through experimental testing and linear fitting. , and Relationship: （2） The regulations stipulate that when the tractor (27) is in an upward posture, the pitch angle is... The pitch angle is positive when the tractor (27) is in a downward pitching position. It is a negative value; Substituting Formula 2 into Formula 1, we get （3） For the selected tractor (27) and rotary tiller (29). , and All are constant values. , , , , , These are parameters to be determined and need to be identified through experimental testing and linear fitting. The stroke of the piston rod of the second lifting hydraulic cylinder (7-2) is measured in real time by the stroke sensor (16). The data is obtained in real time by tilt attitude sensor (28); S2, Stability Control Method The speed measuring radar (31) uses real-time dynamic carrier phase differential technology to monitor the working speed of the tractor (27) in real time. When the working speed of the tractor (27) is relatively fast, the first lifting hydraulic cylinder (7-1) and the second lifting hydraulic cylinder (7-2) are controlled to speed up the action. Conversely, the first lifting hydraulic cylinder (7-1) and the second lifting hydraulic cylinder (7-2) are controlled to slow down the action. The tillage depth dynamic monitoring and stability control method is implemented through a tillage depth dynamic monitoring and stability control system, which includes: a tillage depth monitoring unit, a first lifting hydraulic cylinder (7-1), and a second lifting hydraulic cylinder (7-2). The tillage depth monitoring unit includes a controller, a speed measuring radar (31), and a tilt attitude sensor (28) fixed on the tractor (27); the tractor (27) is connected to the rotary tiller (29) via a suspension lowering rod (30); the piston rods of the first lifting hydraulic cylinder (7-1) and the second lifting hydraulic cylinder (7-2) extend upward and are hinged to the bottom of the suspension lowering rod (30); a stroke sensor (16) is provided on the second lifting hydraulic cylinder (7-2); and a hydraulic actuator (18) is provided on the tractor (27).

2. The method for dynamic monitoring and stability control of tillage depth as described in claim 1, characterized in that, When solving for the undetermined parameters, the tractor (27) is parked on the tilt-adjustable lifting platform and adjusted to... ≥0, the stroke of the first lifting hydraulic cylinder (7-1) and the second lifting hydraulic cylinder (7-2) will be... Fixed in a certain position, assuming The range of values ​​for ≥0 is (0, ... max1 If the angle is adjusted via a lifting platform, the angle change increment is 0.

1. max1 Record the swing angle of the suspension lower lever (30) at different tilt angles in sequence. The value can then be obtained through linear fitting. , The parameter value; similarly, park the tractor (27) on the tilt-adjustable lifting platform and adjust it to <0, the stroke of the first lifting hydraulic cylinder (7-1) and the second lifting hydraulic cylinder (7-2) is reduced. Fixed in a certain position, assuming The range of values ​​for <0 is (— max2 If the value is 0, then the angle is adjusted by the lifting platform, with the angle change step being 0.

1. max2 Record the swing angle of the suspension lower lever (30) at different tilt angles in sequence. The value can then be obtained through linear fitting. , The value of the parameter; At the same time, the tractor (27) is parked on flat ground, assuming the strokes of the first lifting hydraulic cylinder (7-1) and the second lifting hydraulic cylinder (7-2) are... The range of values ​​for is (0, ...). -max Then, by adjusting the stroke of the first lifting hydraulic cylinder (7-1) and the second lifting hydraulic cylinder (7-2), the stroke variation step is 0.

1. -max Record the swing angle of the suspension lower lever (30) under different strokes in sequence. The value can then be obtained through linear fitting. The value of the parameter.

3. The method for dynamic monitoring and stability control of tillage depth as described in claim 1, characterized in that, The tillage depth dynamic monitoring and stability control system also includes a stability control unit; the stability control unit includes an oil tank (1), a hydraulic pump (2), a three-position six-way proportional multi-way valve first section (4), a first check valve (5), a second check valve (6), a third check valve (8), a first speed regulating valve (9), a fourth check valve (10), a fifth check valve (11), a sixth check valve (12), a seventh check valve (13), a second speed regulating valve (14), an eighth check valve (15), and a three-position six-way proportional multi-way valve second section (17); The hydraulic pump (2) is connected to the engine drive of the tractor (27); the P port and F port of the first section (4) of the three-position six-way proportional multi-way valve and the P port of the second section (17) of the three-position six-way proportional multi-way valve are connected to the oil outlet of the hydraulic pump (2); the A port of the second section (17) of the three-position six-way proportional multi-way valve is connected to the rodless chamber of the hydraulic actuator (18), the B port is connected to the rod chamber of the hydraulic actuator (18), and the F port is connected to the E port of the first section (4) of the three-position six-way proportional multi-way valve; the oil inlet of the first check valve (5), The outlet of the second check valve (6), the inlet of the fourth check valve (10), and the outlet of the fifth check valve (11) are connected to port A of the first section (4) of the three-position six-way proportional multi-way valve; the outlet of the first check valve (5) and the outlet of the third check valve (8) are connected to port A of the first speed control valve (9); the inlet of the second check valve (6) and the inlet of the eighth check valve (15) are connected to port B of the first speed control valve (9); the inlet of the third check valve (8) and the outlet of the eighth check valve (15) are connected to the first speed control valve (9). The rodless chamber of the lowering hydraulic cylinder (7-1) is connected; the oil outlet of the fourth check valve (10) and the oil outlet of the seventh check valve (13) are connected to the A port of the second speed regulating valve (14); the oil inlet of the fifth check valve (11) and the oil inlet of the sixth check valve (12) are connected to the B port of the second speed regulating valve (14); the oil outlet of the sixth check valve (12) and the oil inlet of the seventh check valve (13) are connected to the rodless chamber of the second lifting hydraulic cylinder (7-2); the rod chamber of the first lifting hydraulic cylinder (7-1) and the second lifting hydraulic cylinder The rod chamber of (7-2) is connected to port B of the first section (4) of the three-position six-way proportional multi-way valve; the oil inlet of the hydraulic pump (2), port E of the second section (17) of the three-position six-way proportional multi-way valve, port T of the first section (4) of the three-position six-way proportional multi-way valve, and port T of the second section (17) of the three-position six-way proportional multi-way valve are connected to the oil tank (1); the opening degree of the first speed control valve (9) and the second speed control valve (14) is the same; the speed measuring radar (31), the tilt attitude sensor (28), and the stroke sensor (16) are electrically connected to the controller respectively.

4. The method for dynamic monitoring and stability control of tillage depth as described in claim 3, characterized in that, It also includes a filtration unit; the filtration unit includes a spring-loaded check valve (20) and a filter (22); the T port of the first section (4) of the three-position six-way proportional multi-way valve and the T port of the second section (17) of the three-position six-way proportional multi-way valve are connected to the oil inlet of the spring-loaded check valve (20), and the oil outlet of the spring-loaded check valve (20) is connected to the oil tank (1); the two ends of the filter (22) are connected to the oil inlet and oil outlet of the spring-loaded check valve (20) respectively.

5. The method for dynamic monitoring and stability control of tillage depth as described in claim 4, characterized in that, It also includes a cooling unit; the cooling unit includes a hydraulic oil temperature sensor (21), a cooler (23), a third speed control valve (24) and a shut-off valve (25); the oil outlet pipes of the spring-loaded check valve (20) and the filter (22) pass through the cooler (23) and are connected to the oil tank (1); the hydraulic oil temperature sensor (21) is connected to the oil tank (1); the A port of the third speed control valve (24) is connected to the shut-off valve (25), and the B port is connected to the inlet of the cooler (23).

6. A method for dynamic monitoring and stability control of tillage depth as described in any one of claims 3 to 5, characterized in that, It also includes a safety valve (3); the oil inlet of the safety valve (3) is connected to the oil outlet of the hydraulic pump (2), and the oil outlet is connected to the oil tank (1).

7. A method for dynamic monitoring and stability control of tillage depth as described in claim 4 or 5, characterized in that, It also includes a pressure sensor (26) and a proportional relief valve (19); the T port of the first section (4) of the three-position six-way proportional multi-way valve and the T port of the second section (17) of the three-position six-way proportional multi-way valve are connected to the oil inlet of the proportional relief valve (19); the oil outlet of the proportional relief valve (19) is connected to the oil inlet of the spring-loaded check valve (20); the pressure sensor (26) is connected to the oil inlet pipeline of the proportional relief valve (19).

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