CN107182313B - Self-excitation vibration subsoiler and tilling depth measurement and control method - Google Patents

Abstract

The invention discloses a self-excited vibration subsoiler and a cultivation depth measurement and control method thereof, wherein the self-excited vibration subsoiler comprises a rack, a detection device, a hydraulic device and a plurality of self-excited vibration subsoilers, wherein: the detection device is arranged on the frame, and the self-excited vibration subsoiling monomers and the hydraulic device are arranged on the frame; the self-excited vibration subsoiler is used for loosening soil, the hydraulic device is used as a vibration source, the subsoiler is vibrated by coaction with soil, the detection device is used for detecting the soil penetration depth of the self-excited vibration subsoiler, and the hydraulic device is controlled according to the soil penetration depth, so that the tilling depth variation is controlled within an allowable range.

Description

Self-excited vibrating subsoiler and method of tillage depth measurement and control

technical field

The invention belongs to the technical field of agricultural machinery, and relates to a self-excited vibration subsoiler and a tillage depth measurement and control method, which are mainly used in the field of soil subsoiler farming.

Background technique

Soil cultivation is an important part of agricultural production. Due to the long-term use of unreasonable farming methods such as shallow rotation and plowing, the quality of cultivated land in my country has been declining year by year, and crop production has been seriously reduced. Subsoiling soil preparation technology is to loosen the soil without turning the soil, which can effectively break the plow bottom layer and improve the soil aggregate structure. It has obvious advantages in soil improvement effect and has been vigorously promoted in recent years. Self-excited vibration subsoiling technology has obvious drag reduction effect. At present, self-excited vibration subsoilers use springs as excitation sources, so that the upper end of the subsoiler is connected to the frame through springs. Swing under the joint action of resistance and spring force, so as to achieve the effect of reducing drag. However, due to the fixed spring stiffness and limited preload adjustment range, the self-excited vibratory subsoiler with the spring as the excitation source has a large difference in soil specific resistance, poor adaptability and intermittent failure when operating in different areas, resulting in plowing Deep stability cannot be guaranteed.

In the prior art, a horizontal vibrating device is installed before the frame and the shovel handle. The horizontal vibrating device includes a spring and a hydraulic cylinder set inside the spring. This design still uses the spring as the excitation source. A hydraulic cylinder is added inside the spring. By adjusting the amount of hydraulic oil in the hydraulic cylinder, the expansion and contraction of the vibration spring can be controlled, and the maximum expansion and contraction position of the spring is limited to ensure the plowing depth.

The invention uses a hydraulic cylinder as the excitation source and is equipped with a tillage depth detection device. The tillage depth detection device monitors the tillage depth in real time and adjusts the working pressure of the hydraulic cylinder with the variation of the tillage depth as an index, so that the soil resistance can be matched with the excitation source in real time to ensure the tillage depth. Under the premise of the subsoiling shovel to achieve the optimal drag reduction effect.

Compared with the prior art, the present invention has the following advantages;

1. Using the hydraulic cylinder as the excitation source can realize the real-time adjustment of the hydraulic pressure of the hydraulic cylinder, avoiding the intermittent failure caused by insufficient rigidity when the spring is the excitation source, so there is no need to increase the expansion and contraction control device, and the subsoiling single structure is simplified.

2. Real-time detection of tillage depth, taking the variation of tillage depth as the basis for regulating the working pressure of hydraulic cylinders, and adding feedback links can ensure the consistency of tillage depth more accurately and with evidence.

Contents of the invention

For realizing the purpose of the present invention, adopt following technical scheme to realize:

A self-excited vibration subsoiling machine, including a frame, a detection device, a hydraulic device, and a plurality of self-excited vibration subsoiling units, characterized in that: the detection device is installed on the frame, and the plurality of self-excited vibrations subsoiling units And the hydraulic device is installed on the frame; the self-excited vibration subsoiling unit is used for loosening the soil, the hydraulic device is used as the excitation source of the self-excited vibration subsoiling unit, and the detection device is used to detect the self-excited vibration subsoiling unit The depth of entry into the soil, and control the hydraulic device according to the depth of entry into the soil, and then control the tillage depth.

The self-excited vibration subsoiler, wherein: the self-excited vibration subsoiler includes a monomer fixing frame, a subsoiler connecting plate, a subsoiler, a hydraulic cylinder, and a suppression device; the suppression device includes a suppression wheel, a suppression Wheel connection arm.

The self-excited vibration subsoiling machine, wherein: the self-excited vibration subsoiling unit is fixed on the frame through the unit fixing frame; the earring at the front end of the hydraulic cylinder is hinged with the upper end of the unit fixing bracket through a pin shaft, and the earring at the other end of the hydraulic cylinder The connecting plate of the subsoiling shovel is hinged with the second pin shaft; the front end of the connecting plate of the subsoiling shovel is hinged with the lower end of the single fixing frame through the first pin shaft. The first connecting plate of the subsoiling shovel can rotate around the pin shaft. The rear end is fixedly connected to the upper end of the subsoiling shovel.

The self-excited vibration subsoiler, wherein: the upper end of the suppression device is connected to the end of the subsoiler connecting plate through the third pin shaft, the suppression device can rotate around the pin shaft, the suppression device includes a connecting arm, and the upper end of the connection arm passes through the third pin The shaft is connected with the end of the connecting plate of the subsoiling shovel, the lower end of the connecting arm is connected with the rotating shaft of the pressing wheel, and the pressing wheel can rotate and roll around the lower end of the connecting arm.

The self-excited vibrating subsoiler, wherein: the hydraulic device includes an accumulator, a filter, a valve group, and connecting pipes; Cylinder connection, each proportional pressure reducing valve independently controls a hydraulic cylinder, and the working pressure of the hydraulic cylinder is adjusted by controlling the pressure of the oil outlet of the proportional pressure reducing valve.

The self-excited vibrating subsoiler, wherein: the oil inlet of the hydraulic device is connected to the hydraulic output port of the tractor, and is connected to the oil inlet of the valve group through a filter and an accumulator, and the oil return port of the hydraulic device is connected to the hydraulic return port of the tractor. The oil port is connected and directly connected with the oil return port of the valve group, and the oil outlet of the valve group is connected to the rodless cavity of each hydraulic cylinder.

The self-excited vibration subsoiler is characterized in that: the detection device includes a main controller, a connecting circuit, a single controller combination, and a sensor combination; the single controller combination includes a plurality of single controllers, and the sensor combination Including a first angle sensor and a second angle sensor.

The self-excited vibrating subsoiler, wherein: the main controller is combined with a touch screen and a single controller through a connection circuit, and the touch screen is installed with a tractor cab; each single controller is combined with a sensor; each sensor The first angle sensor in the combination is horizontally fixed above the connecting plate of the subsoiling shovel, and the second angle sensor is vertically fixed above the connecting arm of the pressing wheel.

The self-excited vibrating subsoiler, wherein: the unit controller detects the tillage depth, coefficient of variation of tillage depth, and average tillage depth through a combination of sensors installed on the self-excited vibrating subsoiler unit and sends them to the main controller; The body controller also adjusts the working pressure of the hydraulic cylinder by controlling the proportional pressure reducing valve to stabilize the plowing depth.

A self-excited vibration subsoiler measurement and control method for a self-excited vibratory subsoiler as described in one of the above, wherein:

The method comprises the steps of:

a. Input the working parameters of the self-excited vibration subsoiling unit through the touch screen;

b. The main controller determines the size parameters of the self-excited vibration subsoiling unit according to the data input by the touch screen and controls the work of the unit controller;

c. The single controller calculates the working parameters of the subsoiler;

d. The single controller controls the working pressure of the hydraulic cylinder according to the calculated working parameters;

e. The single controller sends the calculated working parameters to the main controller;

f. The main controller sends the received multiple monomer working parameters to the touch screen for display.

The self-excited vibration subsoiler measurement and control method, wherein: the method is specifically carried out as follows:

a. Input the self-excited vibration subsoiling unit size parameters H, h, L, L1, L2, R on the touch screen, set the lower limit of tillage depth variation V _L , the upper limit of tillage depth variation V _U , and the initial setting of the proportional pressure reducing valve Pressure P _s ; start self-excited vibration subsoiling depth control through the touch screen;

b. The main controller determines the size parameters H, h, L, L1, L2 and R of the self-excited vibration subsoiling unit according to the data input by the touch screen, and sets the lower limit of tillage depth variation V _L , the upper limit of tillage depth variation V _U , and the proportional reduction The pressure valve initially sets the pressure P _s and sends it to the unit controller combination; after the unit controller receives the data, it starts to read the data of the angle sensor combination, and calculates the current tillage depth D _n and variation of the tillage depth of the subsoiling unit Coefficient V _D , average tillage depth D _m , where: H is the vertical distance from the first pin axis to the tip of the subsoiling shovel; h is the vertical distance from the first pin axis to the third pin axis; L is the vertical distance from the first pin axis to the The horizontal distance of the centerline of the subsoiler shovel; L1 is the vertical distance between the third pin axis and the rotation axis of the pressing wheel; L2 is the distance between the centerline of the subsoiling shovel and the centerline of the connecting arm; R is the radius of the pressing wheel;

c. In step b, the method for calculating the current tillage depth D _n of the subsoiler is:

c1) As the subsoiler shovel enters the soil, the angle between the connecting arm of the pressing wheel detected by the first angle sensor and the horizontal direction is α, and at this time, the current plowing depth D _n of the subsoiler shovel 111 is calculated according to the following formula;

D _n =Hh-(L1×sin α)-R

c2) When the subsoiling shovel vibrates, the second angle sensor detects the angle α ₁ between the subsoiling shovel mounting plate and the horizontal direction, and the second angle sensor detects the angle α between the pressing wheel mounting plate and the horizontal direction. At this time, according to the following The formula calculates the current tillage depth D _n of the subsoiler;

D _n ＝Hcos a ₁ -L1sin a+L2sin a ₁ -h cos a ₁ -R

The average value of tillage depth is calculated according to the following formula:

In the formula: n—the number of sampling points;

The coefficient of variation of tillage depth is calculated according to the following formula:

In the formula: S—Standard deviation of plowing depth;

d. The single controller sends the calculated current tillage depth D _n , tillage depth variation coefficient V _D , and average tillage depth D _m to the main controller, and the main controller sends them to the touch screen for display after receiving them;

e. The tillage depth sampling interval of the single controller is 0.5s. After accumulatively sampling a predetermined number of sample points, the coefficient of variation V _D of the predetermined number of sample points is calculated. The single controller varies according to the tillage depth. The coefficient V _D adjusts the working pressure of the hydraulic cylinder to stabilize the plowing depth.

The self-excited vibration subsoiling machine measurement and control method, wherein the single controller adopts a fuzzy control algorithm to control the pressure of the hydraulic cylinder: a fuzzy controller is established according to the fuzzy control theory, and the input variables of the fuzzy controller are the variation coefficient error e, Variation coefficient error rate of change ec, the output is the proportional pressure reducing valve control voltage adjustment value u.

The self-excited vibration subsoiler measurement and control method, wherein the method for determining the input variables of the fuzzy controller is:

(1) If V _L < V _D < V _U , the single controller considers that the variation of the current tillage depth is within the set range, and the working pressure of the hydraulic cylinder is not adjusted, then the variation coefficient error e=0;

(2) If V _D > V _U , the single controller thinks that the current tillage depth variation deviates from the target tillage depth variation and exceeds the set tillage depth variation upper limit, and the tillage depth stability is poor, and it is necessary to increase the working pressure of the hydraulic cylinder, then the variation coefficient error e=V _D -V _U ;

(3) If V _D < V _L , the single controller thinks that the current tillage depth variation deviates from the target tillage depth variation and is lower than the set tillage depth variation lower limit, and the drag reduction effect is poor, so the working pressure of the hydraulic cylinder needs to be reduced, then the variation coefficient Error e=V _D -V _L ;

Among them: the rate of change of the coefficient of variation error ec is the ratio of the error of the coefficient of variation in this period to the corresponding time T in this period.

The self-excited vibration subsoiler measurement and control method, wherein the establishment of the fuzzy controller is divided into the following steps:

aAccording to the preliminary test, the value range of the input variable e of the fuzzy controller is e=[-10,10], the value range of ec=[-20,20], and the value range of the output variable u=[-3,3 ];

b Define language variables E, EC, language values E', EC' for input variables e, ec, and define language variables E, EC discrete domain as {-6, -4, -2, 0, 2, 4, 6 }, language value E', EC' value range is {negative big (NB), negative middle (NM), negative small (NS), zero (Z), positive small (PS), positive middle (PM), positive big (PB )}; define linguistic variable U and linguistic value U′ for the output variable u, and define the discrete domain of linguistic variable U as {-6, -4, -2, 0, 2, 4, 6}, linguistic value U′ The domain is {Negative Big (NB), Negative Medium (NM), Negative Small (NS), Zero (Z), Positive Small (PS), Positive Medium (PM), Positive Big (PB)};

c According to the value range of input variables e and ec and the discrete domain of linguistic variables E and EC, the quantization factors k _e =0.6 and k _ec =0.3 of input variables e and ec are calculated; according to the value range of output variable u and the discrete universe of language variable U, the quantization factor k _u of the output variable u is calculated to be 0.5;

d Select trigonometric functions as the membership functions of the linguistic values E, EC, and U, and establish the membership functions with the elements in the domain of linguistic variables as the central values;

e establish a fuzzy control rule library, as shown in the following table:

The self-excited vibration subsoiler measurement and control method, wherein the working process of the fuzzy controller is as follows:

a The fuzzy controller calculates the variation coefficient error e and the variation coefficient error change rate ec in real time;

b Perform fuzzy processing on the variation coefficient error e and the variation coefficient error change rate ec, and quantify the variation coefficient error e and the variation coefficient change rate ec into language variables E and EC through quantization factors k _e and k _ec ;

c The fuzzy controller obtains the linguistic values A, B, A, B ∈ U′ of the linguistic variables E and EC according to the membership function and the principle of the maximum degree of membership;

d The fuzzy controller performs fuzzy reasoning according to the fuzzy control rule base, and the linguistic value C to which the linguistic variable U belongs is determined by the linguistic values A and B, C∈U′;

e. Perform defuzzification processing on the language value C, calculate the weighted average value of each element in the language value U′ set and its degree of membership according to the center of gravity method, and perform rounding to obtain the language variable U;

The f fuzzy controller converts the language variable U into the proportional decompression valve control voltage adjustment value u through the quantization factor k _u .

Description of drawings

Fig. 1 is the overall structure schematic diagram of self-excited vibration subsoiler of the present invention

Fig. 2 is the front view of the self-excited vibration subsoiling unit of the present invention

Fig. 3 is the structural representation of the suppression device of the present invention

Fig. 4 is a structural schematic diagram of the hydraulic device of the self-excited vibration subsoiler of the present invention

Fig. 5 is a structural schematic diagram of the self-excited vibration subsoiler detection device of the present invention

Figure 6 is a schematic diagram of the size parameters of the self-excited vibration subsoiling monomer of the present invention

Fig. 7 is a schematic diagram of the self-excited vibration subsoiling monomer structure of the present invention

Fig. 8 is a schematic diagram of the non-vibration state of the self-excited vibration subsoiling unit in the soil of the present invention

Fig. 9 is a schematic diagram of the vibration state of the self-excited vibration subsoiling unit in the present invention

Fig. 10 is a flowchart of plowing depth control of the single controller of the self-excited vibrating subsoiler of the present invention

Fig. 11 is a structural diagram of the fuzzy controller of the single controller of the self-excited vibration subsoiler of the present invention

Fig. 12 is the shape and distribution diagram of the membership function adopted by the fuzzy control algorithm of the self-excited vibration subsoiling machine monomer controller of the present invention

reference sign

1 self-excited vibration subsoiling unit 101 hydraulic cylinder 102 pin shaft

103 pin shaft 104 single body fixing frame 105 pin shaft

106 subsoiling shovel connecting plate 107 bolts 108 bolts

109 Suppression device 1091 Suppression wheel connecting arm 1092 Suppression wheel

110 pin shaft 111 subsoiling shovel 2 ground wheels

3 detection device 301 main controller 302 connection circuit

303 single controller combination 3031 single controller 304 sensor combination

3041 angle sensor 3042 angle sensor 4 touch screen

5 hydraulic device 501 valve group 5011 proportional pressure reducing valve

502 connecting pipe fittings 503 accumulator 504 filter

6 racks 7 three-point suspension

Detailed ways

As shown in Figure 1, the present invention provides a self-excited vibration subsoiler, including a three-point suspension 7, a frame 6, ground wheels 2, a detection device 3, a touch screen 4, a hydraulic device 5, and a self-excited vibration subsoiler 1. The ground wheels 2 are installed on both sides of the frame 6, the three-point suspension 7 is installed in the middle of the front of the frame, and is used to connect with the tractor for farming. The detection device 3 is installed on the frame 6, and multiple self-excited vibrations are deep The loosening unit 1 and the hydraulic device 5 are installed on the frame 6. The self-excited vibration subsoiling unit 1 is used for loosening the soil, and the hydraulic unit 5 is used as the excitation source of the self-excited vibration subsoiling unit 1. The effect makes the submersible unit vibrate. The detection device 3 is used to detect the penetration depth of the self-excited vibration subsoiling unit 1, and control the hydraulic device according to the penetration depth, so as to control the tillage depth variation within the allowable range.

As shown in Figure 2, the self-excited vibration subsoiling unit 1 includes a unit fixing frame 104, a subsoiling shovel connecting plate 106, a subsoiling shovel 111, a hydraulic cylinder 101, and a suppression device 109, and the suppression device includes a suppression wheel 1092, a suppression wheel Connecting arm 1091 . The self-excited vibration subsoiler unit 1 is fixed on the subsoiler frame 6 through the unit holder 104 . The earring at the front end of the hydraulic cylinder 101 is hinged to the upper end of the single fixing frame 104 through the pin 102, and the earring at the other end of the hydraulic cylinder 101 is hinged to the connecting plate 106 of the subsoiling shovel through the pin 103; Body fixed frame 104 lower ends are hinged, and subsoiling shovel connecting plate 106 can rotate around bearing pin 105, and subsoiling shovel connecting plate 106 rear end is fixedly connected the upper end of subsoiling shovel 111 by bolt 107, bolt 108, subsoiling shovel 111 from upper end It is hooked downward as a whole and is used for loosening soil. As shown in Figures 2 and 3, the upper end of the suppression device 109 is connected to the end of the subsoiler connecting plate 106 through a pin shaft 110, and the suppression device 109 can rotate around the pin shaft 110. The specific suppression device 109 includes a connecting arm 1091, and the upper end of the connecting arm 1091 The pin shaft 110 is connected with the end of the subsoiler connecting plate 106, and the lower end of the connecting arm 1091 is connected with the rotation shaft of the pressing wheel 1092, and the pressing wheel 1092 can rotate and roll around the lower end of the connecting arm 1091.

During the working process, the pressing wheel 1092 is always in contact with the ground, a certain working pressure is maintained in the hydraulic cylinder 101, and the self-excited vibration subsoiling unit 1 vibrates due to changes in soil resistance. When the soil resistance increases, the subsoiler shovel 111 tilts up, and the plowing depth becomes shallower. The subsoiler shovel 111 drives the subsoiler connecting plate 106 to rotate around the pin shaft 105, the hydraulic cylinder 101 is compressed, and the subsoiling shovel connecting plate 106 is aligned with the horizontal direction. When the included angle _α increases, the inclination α between the connecting arm 1091 of the pressing wheel and the horizontal direction also increases; when the soil resistance decreases, the subsoiler shovel 111 goes down, and the plowing depth increases, and the subsoiler shovel 111 drives the subsoiler shovel connecting plate 106 around the pin The shaft 105 rotates, the hydraulic cylinder 101 extends, the angle α between the subsoiling shovel connecting plate 106 and the horizontal direction _decreases , and the angle α between the pressing wheel connecting arm 1091 and the horizontal direction also decreases.

The self-excited vibration subsoiler provided by the present invention includes a hydraulic device 5 and a detection device 3 .

As shown in Figure 4, the hydraulic device 5 includes an accumulator 503, a filter 504, a valve group 501, and a connecting pipe 502; Connection; each proportional pressure reducing valve 5011 independently controls a hydraulic cylinder 101 without interfering with each other, and the working pressure of the hydraulic cylinder 101 can be adjusted by controlling the pressure of the oil outlet A of the proportional pressure reducing valve 5011.

The oil inlet P of the hydraulic device 5 is connected to the hydraulic output port of the tractor, and is connected to the oil inlet P of the valve group 501 through the filter 504 and the accumulator 503, and the oil return port T of the hydraulic device 5 is connected to the hydraulic oil return port of the tractor. And directly connected with the oil return port T of the valve group 501, the accumulator 503 has the function of absorbing hydraulic pulsation and stabilizing the pressure; the oil outlet A of the valve group 501 is respectively connected to the rodless cavity of each hydraulic cylinder 101.

As shown in Figure 5, the detection device 3 includes a main controller 301, a connection circuit 302, a single controller combination 303, and a sensor combination 304. The single controller 3031 and the sensor combination 304 include an angle sensor 3041 and an angle sensor 3042 . The main controller 301 is connected with the touch screen 4 and the unit controller combination 303 through the connection circuit 302, and the touch screen 4 is placed in the cab of the tractor, which is convenient for the staff to set the initial parameters and read the current working parameters; each unit controller 3031 is connected with the A sensor combination 304 is connected, and the sensor combination 304 includes an angle sensor 3041 and an angle sensor 3042; the angle sensor 3042 is horizontally fixed above the subsoiling shovel connecting plate 106, and the angle sensor 3041 is vertically fixed above the pressing wheel connecting arm 1091. The detection device 3 in the present invention has a main controller 301 and several individual controllers 3031 with different communication addresses, and one individual controller 3031 is installed on each self-excited vibrating subsoiling individual 1 . The main controller 301 reads the data of each monomer controller in a polling manner, and sends it to the touch screen 4 for display; Working parameters such as detected tillage depth, variation coefficient of tillage depth, and average tillage depth are sent to the main controller 301. On the other hand, the single controller 3031 adjusts the working pressure of the hydraulic cylinder 101 by controlling the proportional pressure reducing valve 5011 to stabilize the tillage depth. In order to ensure good expandability of the self-excited vibration subsoiling machine tillage depth measurement and control system, the main controller 301 and the unit controller 3031 adopt the RS485 communication protocol, and the unit controller 3031 can be expanded according to the number of subsoiling units 1.

The present invention provides a method for measuring and controlling the tillage depth of a self-excited vibration subsoiler, which calculates the current tillage depth by combining the size parameters of the self-excited vibration subsoiler unit 1 and the angle changes of the subsoiler connecting plate 106 and the pressing wheel connecting arm 1091.

In order to facilitate the description of the size parameters of the self-excited vibration subsoiling unit 1, auxiliary straight lines AB, BC, and CD are made. As shown in Figure 6, point A is set at the pin shaft 105, the straight line AB is the horizontal line where the pin shaft 105 and the subsoiling shovel connecting plate 106 are located, the straight line BC is the vertical line where the subsoiling shovel 111 is located, and the straight line AB and the straight line BC intersect at B point; point D is set at the pin shaft 110, the straight line CD is the horizontal line where the pin shaft 110 and the subsoiling shovel connecting plate 106 are located, and the intersection of the straight line BC and the straight line CD is set as point C. In Fig. 6, H is the distance from the pin shaft 105 to the shovel tip, L is the distance between A and B, h is the distance between B and C, _L2 is the distance between C and D, and _L1 is the length of the connecting arm of the pressing wheel , R is the radius of the pressing wheel.

In order to facilitate the analysis of the angle change of the subsoiling shovel connecting plate 106 and the pressing wheel connecting plate 1091 when the self-excited vibration subsoiling unit 1 vibrates, a simplified model of the self-excited vibration subsoiling unit is drawn, as shown in Figure 7. During the vibration process, the pressing wheel 1092 is in contact with the ground all the time. When the soil resistance increases, the subsoiling shovel 111 tilts up, and the included angle _α1 between the subsoiling shovel connecting plate 106 and the horizontal direction increases, and the connection arm 1091 of the suppressing wheel connects with the horizontal direction. The inclination angle α also increases; when the soil resistance decreases, the subsoiling shovel 111 descends, the subsoiling shovel connecting plate 106 and the horizontal angle α ₁ decrease, and the angle α between the pressing wheel connecting arm 1091 and the horizontal direction also decreases.

A self-excited vibration subsoiler plowing depth measurement and control method, the method includes the following steps:

a. Connect the oil inlet P and oil return port T of the hydraulic device 5 with the hydraulic output port and the oil return port of the tractor, and input the size parameters H, h, L, L1, L2, R, set the lower limit of tillage depth variation V _L and the upper limit of tillage depth variation V _U (the lower limit of tillage depth variation V _L and the upper limit of tillage depth variation V _U can be set comprehensively considering the quality requirements of agronomic land preparation and the degree of drag reduction), proportional decompression Initially set the pressure P _s of the valve 5011, click the "Start" button on the touch screen to start the self-excited vibration subsoiling depth measurement and control machine;

b. The main controller 301 reads the size parameters H, h, L, L1, L2, and R of the self-excited vibration subsoiling unit 1 from the touch screen 4, and sets the lower limit of tillage depth variation V _L , the upper limit of tillage depth variation V _U , and the ratio The pressure reducing valve 5011 initially sets the pressure P _s and sends it to the unit controller combination 303; taking the unit controller 3031 with address 01 as an example, after receiving the data, the unit controller 3031 starts to read the angle sensor 3041, Based on the data of the angle sensor 3042, the current tillage depth D _n , the coefficient of variation of the tillage depth V _D , and the average tillage depth D _m of the subsoiling shovel 111 are calculated;

c. In step b, the method of calculating the current tillage depth D _n , coefficient of variation of tillage depth V _D , and average tillage depth D _m of the subsoiler shovel 111 is:

c1) As the subsoiler shovel 111 enters the soil, the angle sensor 3041 detects that the angle between the connecting arm of the pressing wheel and the horizontal direction is α, as shown in Figure 8. At this time, the current plowing depth D _n of the subsoiler shovel 111 is calculated according to the following formula;

D _n =Hh-(L1×sin a)-R

c2) When the subsoiling shovel 111 vibrates, the angle sensor 3042 detects the angle α ₁ between the subsoiling shovel mounting plate 106 and the horizontal direction, and the angle sensor 3041 detects the angle α between the pressing wheel mounting plate and the horizontal direction, as shown in Figure 9, At this time, the current tillage depth D _n of the subsoiler is calculated according to the following formula;

D _n ＝Hcosa ₁ -L1sin a+L2sin a ₁ -h cos a ₁ -R

c3) Calculate the average value of tillage depth according to the following formula:

In the formula:

n—the number of sampling points;

c4) Calculate the average value of tillage depth according to the following formula:

In the formula:

S—Standard deviation of tillage depth, unit cm

d. The single controller 3031 sends the calculated current tillage depth D _n , tillage depth variation coefficient V _D , and average tillage depth D _m to the main controller 301, and the main controller 301 sends them to the touch screen 4 for display after receiving them;

e. Set the sampling interval of the single controller 3031 to 0.5s, and the single controller 3031 compares the real-time calculated tillage depth variation coefficient V _D with the set tillage depth variation lower limit V _L and tillage depth variation upper limit V _U , according to the comparison result as the working pressure of the control hydraulic cylinder.

The algorithm of the single controller 3031 controlling the working pressure of the hydraulic cylinder is shown in FIG. 10 . The single controller 3031 calculates the variation coefficient error e and the variation coefficient error _{change rate ec according to the lower limit V L and} the upper limit V _U of the variation coefficient V D of the tillage depth, which are set as the input of the fuzzy controller. The output proportional decompression valve controls the voltage to adjust the amount u, and then adjusts the working pressure of the hydraulic cylinder.

The method of determining the input variable (variation coefficient error e) of the fuzzy controller is:

(1) If V _L < V _D < V _U , the single controller considers that the variation of the current tillage depth is within the set range, and the working pressure of the hydraulic cylinder is not adjusted, then the variation coefficient error e=0;

(2) If V _D > V _U , the single controller thinks that the current tillage depth variation deviates from the target tillage depth variation and exceeds the set tillage depth variation upper limit, and the tillage depth stability is poor, so it is necessary to increase the working pressure of the hydraulic cylinder. At this time, the variation coefficient Error e=v _D -v _U ;

(3) If v _D < v _L , the single controller believes that the current tillage depth variation deviates from the target tillage depth variation and is lower than the set tillage depth variation lower limit, and the drag reduction effect is poor, so the working pressure of the hydraulic cylinder needs to be reduced, then the variation coefficient Error e=V _D -V _L ;

(4) The rate of change of the coefficient of variation error ec is the ratio of the error of the coefficient of variation in the current period to the corresponding time T in the current period.

The structure of the fuzzy controller is shown in Figure 11. The establishment of the fuzzy controller is divided into the following steps:

aAccording to the preliminary test, the value range of the input variable e of the fuzzy controller is e=[-10,10], the value range of ec=[-20,20], and the value range of the output variable u=[-3,3 ];

b Define language variables E, EC, language values E', EC' for input variables e, ec, and define language variables E, EC discrete domain as {-6, -4, -2, 0, 2, 4, 6 }, language value E', EC' value range is {negative big (NB), negative middle (NM), negative small (NS), zero (Z), positive small (PS), positive middle (PM), positive big (PB )}; define linguistic variable U and linguistic value U′ for the output variable, and define the discrete domain of linguistic variable U as {-6, -4, -2, 0, 2, 4, 6}, and the value domain of linguistic value U′ It is {Negative Big (NB), Negative Medium (NM), Negative Small (NS), Zero (Z), Positive Small (PS), Positive Medium (PM), Positive Big (PB)};

c According to the value range of input variables e and ec and the discrete domain of linguistic variables E and EC, the quantization factors k _e =0.6 and k _ec =0.3 of input variables e and ec are calculated; according to the value range of output variable u and the discrete universe of language variable U, the quantization factor k _u of the output variable u is calculated to be 0.5;

d Select trigonometric functions as the membership functions of the linguistic values E, EC, and U, and establish the membership functions with the elements in the domain of linguistic variables as the center values respectively. The distribution of the membership functions is shown in Figure 12.

e establish a fuzzy control rule library, as shown in the following table:

The working process of the fuzzy controller is as follows:

a The fuzzy controller calculates the variation coefficient error e and the variation coefficient error change rate ec in real time;

b Perform fuzzy processing on the variation coefficient error e and the variation coefficient error change rate ec, and quantify the variation coefficient error e and the variation coefficient change rate ec into language variables E and EC through quantization factors k _e and k _ec ;

c The fuzzy controller obtains the linguistic values A, B, A, B ∈ U′ of the linguistic variables E and EC according to the membership function and the principle of the maximum degree of membership;

d The fuzzy controller performs fuzzy reasoning according to the fuzzy control rule base, and the linguistic value C to which the linguistic variable U belongs is determined by the linguistic values A and B, C∈U′;

e. Perform defuzzification processing on the language value C, calculate the weighted average value of each element in the language value U′ set and its degree of membership according to the center of gravity method, and perform rounding to obtain the language variable U;

The f fuzzy controller converts the language variable _U into the proportional pressure reducing valve control voltage adjustment value u through the quantization factor k u, u>0 means to increase the working pressure of the hydraulic cylinder, and u<0 means to reduce the working pressure of the hydraulic cylinder.

The invention uses the hydraulic cylinder as the excitation source, which can realize the real-time adjustment of the hydraulic pressure of the hydraulic cylinder, and avoids intermittent failure caused by insufficient rigidity when the spring is the excitation source. Therefore, there is no need to increase the expansion and contraction control device, and the single structure of the deep loosening is simplified. The present invention can detect the tillage depth in real time, takes the variation of the tillage depth as the basis for regulating the working pressure of the hydraulic cylinder, adds a feedback link, and can ensure the consistency of the tillage depth more accurately and with a basis.

Claims (1)

1. A self-excited vibration subsoiler measurement and control method, characterized in that: The self-excited vibrating subsoiling machine includes a frame, a detection device, a hydraulic device, and multiple self-excited vibrating subsoiling units, wherein: the detection device is installed on the frame, and multiple self-excited vibrating subsoiling units and hydraulic devices are installed on the On the frame; the self-excited vibration subsoiling unit is used for loosening the soil, the hydraulic device is used as the excitation source of the self-excited vibration subsoiling unit, and the detection device is used to detect the depth of the self-excited vibration subsoiling unit, and according to The depth of soil entry controls the hydraulic device, and then controls the tillage depth; the hydraulic device includes accumulators, filters, valve groups, and connecting pipes; connection, each proportional pressure reducing valve independently controls a hydraulic cylinder, and adjusts the working pressure of the hydraulic cylinder by controlling the pressure of the oil outlet of the proportional pressure reducing valve. Connected to the oil inlet of the valve group, the oil return port of the hydraulic device is connected to the hydraulic oil return port of the tractor, and directly connected to the oil return port of the valve group, and the oil outlet of the valve group is connected to the rodless chamber of each hydraulic cylinder; self-excited The vibrating subsoiling unit is fixed on the frame through the unit fixing frame; the earring at the front end of the hydraulic cylinder is hinged to the upper end of the unit fixing bracket through a pin, and the earring at the other end of the hydraulic cylinder is hinged to the connecting plate of the subsoiling shovel through the second pin shaft; The front end of the shovel connecting plate is hinged to the lower end of the single fixing frame through the first pin shaft, the subsoiling shovel connecting plate can rotate around the pin shaft, and the rear end of the subsoiling shovel connecting plate is fixedly connected to the upper end of the subsoiling shovel; The method is specifically carried out as follows: a. Input the self-excited vibration subsoiling unit size parameters H, h, L, L1, L2, R on the touch screen, set the lower limit of tillage depth variation V _L , the upper limit of tillage depth variation V _U , and the initial setting of the proportional pressure reducing valve Pressure P _s ; start self-excited vibration subsoiling depth control through the touch screen; b. The main controller determines the size parameters H, h, L, L1, L2 and R of the self-excited vibration subsoiling unit according to the data input by the touch screen, and sets the lower limit of tillage depth variation V _L , the upper limit of tillage depth variation V _U , and the proportional reduction The pressure valve initially sets the pressure P _s and sends it to the unit controller combination; after the unit controller receives the data, it starts to read the data of the angle sensor combination, and calculates the current tillage depth D _n and variation of the tillage depth of the subsoiling unit Coefficient V _D , average tillage depth D _m , where: H is the vertical distance from the first pin axis to the tip of the subsoiling shovel; h is the vertical distance from the first pin axis to the third pin axis; L is the vertical distance from the first pin axis to the The horizontal distance of the centerline of the subsoiler shovel; L1 is the vertical distance between the third pin axis and the rotation axis of the pressing wheel; L2 is the distance between the centerline of the subsoiling shovel and the centerline of the connecting arm; R is the radius of the pressing wheel; c. In step b, the method for calculating the current tillage depth D _n of the subsoiler is: c1) As the subsoiler shovel enters the soil, the angle between the connecting arm of the pressing wheel detected by the first angle sensor and the horizontal direction is α, and at this time, the current plowing depth D _n of the subsoiler shovel 111 is calculated according to the following formula; _Dn =Hh-(L1×sina)-R c2) When the subsoiling shovel vibrates, the second angle sensor detects the angle α ₁ between the subsoiling shovel mounting plate and the horizontal direction, and the second angle sensor detects the angle α between the pressing wheel mounting plate and the horizontal direction. At this time, according to the following The formula calculates the current tillage depth D _n of the subsoiler; D _n ＝Hcosa ₁ -L1sina+L2sina ₁ -hcosa ₁ -R The average value of tillage depth is calculated according to the following formula:

In the formula: n—the number of sampling points; The coefficient of variation of tillage depth is calculated according to the following formula:

In the formula: S—Standard deviation of plowing depth; d. The single controller sends the calculated current tillage depth D _n , tillage depth variation coefficient V _D , and average tillage depth D _m to the main controller, and the main controller sends them to the touch screen for display after receiving them; e. The tillage depth sampling interval of the single controller is 0.5s. After accumulatively sampling a predetermined number of sample points, the coefficient of variation V _D of the predetermined number of sample points is calculated. The single controller varies according to the tillage depth. The coefficient V _D adjusts the working pressure of the hydraulic cylinder to stabilize the plowing depth; The single controller adopts the fuzzy control algorithm to control the pressure of the hydraulic cylinder: the fuzzy controller is established according to the fuzzy control theory, the input variables of the fuzzy controller are the variation coefficient error e, the variation coefficient error change rate ec, and the output is proportional decompression Valve control voltage adjustment value u; The method of determining the input variables of the fuzzy controller is: (1) If V _L <V _D <V _U , the single controller considers that the current tillage depth variation is within the set range, and the working pressure of the hydraulic cylinder is not adjusted, then the variation coefficient error e=0; (2) If V _D >V _U , the single controller thinks that the current tillage depth variation deviates from the target tillage depth variation and exceeds the set tillage depth variation upper limit, and the tillage depth stability is poor, and it is necessary to increase the working pressure of the hydraulic cylinder, then the variation coefficient error e=V _D -V _U ; (3) If V _D < V _L , the single controller thinks that the current tillage depth variation deviates from the target tillage depth variation and is lower than the set tillage depth variation lower limit, the drag reduction effect is poor, and the working pressure of the hydraulic cylinder needs to be reduced, then the variation coefficient Error e=V _D -V _L ; Among them: the rate of change of the coefficient of variation error ec is the ratio of the error of the coefficient of variation in this period to the corresponding time T in this period; The establishment of the fuzzy controller is divided into the following steps: aAccording to the preliminary test, the value range of the input variable e of the fuzzy controller is e=[-10,10], the value range of ec=[-20,20], and the value range of the output variable u=[-3,3 ]; b Define language variables E, EC, language values E', EC' for input variables e, ec, and define language variables E, EC discrete domain as {-6, -4, -2, 0, 2, 4, 6 }, language value E', EC' value range is {negative big (NB), negative middle (NM), negative small (NS), zero (Z), positive small (PS), positive middle (PM), positive big (PB )}; define linguistic variable U and linguistic value U′ for the output variable u, and define the discrete domain of linguistic variable U as {-6, -4, -2, 0, 2, 4, 6}, linguistic value U′ The domain is {Negative Big (NB), Negative Medium (NM), Negative Small (NS), Zero (Z), Positive Small (PS), Positive Medium (PM), Positive Big (PB)}; c According to the value range of input variables e and ec and the discrete domain of linguistic variables E and EC, the quantization factors k _e =0.6 and k _ec =0.3 of input variables e and ec are calculated; according to the value range of output variable u and the discrete universe of language variable U, the quantization factor k _u of the output variable u is calculated to be 0.5; d Select trigonometric functions as the membership functions of the linguistic values E, EC, and U, and establish the membership functions with the elements in the domain of linguistic variables as the central values; e establish a fuzzy control rule base; The working process of the described fuzzy controller is as follows: a The fuzzy controller calculates the variation coefficient error e and the variation coefficient error change rate ec in real time; b Perform fuzzy processing on the variation coefficient error e and the variation coefficient error change rate ec, and quantify the variation coefficient error e and the variation coefficient change rate ec into language variables E and EC through quantization factors k _e and k _ec ; c The fuzzy controller obtains the linguistic values A, B, A, B ∈ U′ of the linguistic variables E and EC according to the membership function and the principle of the maximum degree of membership; d The fuzzy controller performs fuzzy reasoning according to the fuzzy control rule base, and the linguistic value C to which the linguistic variable U belongs is determined by the linguistic values A and B, C∈U′; e. Perform defuzzification processing on the language value C, calculate the weighted average value of each element in the language value U′ set and its degree of membership according to the center of gravity method, and perform rounding to obtain the language variable U; The f fuzzy controller converts the language variable U into the proportional decompression valve control voltage adjustment value u through the quantization factor k _u .

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