Method for detecting compaction degree of agricultural tire to soil

Abstract

The invention discloses a method for detecting the soil compaction degree of an agricultural tire, solves the problem of how to reduce the adverse consequence of soil compaction, and belongs to the field of agricultural machinery experiments. The method comprises the following steps: paving a pressure sensing film on soil to be detected, pressing a tire on the pressure sensing film at a set roll angle, counting pressure point positions and corresponding pressure values of three areas on the pressure sensing film, and further calculating the pressure sum Pt of each area; obtaining pressure weights wI, wII and wIII of the three regions according to the influence of the roll angle on the pressures of the different regions, and calculating the total pressure PD corresponding to the roll angle according to the formula: PD = PIwI + PIIwII + PIIIwIII; the total pressure PD corresponding to different roll angles theta D is obtained, and the total grounding pressure # imgabs0 # wD is calculated as the influence weight of the roll angles theta D; and calculating the total compaction degree C according to the PZ. According to the method, the influence mechanism of different roll angles of the tire on the ground pressure distribution and the soil compaction degree is quantified, and a quantitative basis is provided for optimizing the tire width, the tire pressure and mechanical operation conditions.

Description

Technical Field

[0001] The invention relates to a method for detecting the degree of soil compaction by an agricultural tire, and belongs to the field of agricultural machinery testing. Background Art

[0002] With the rapid development of agricultural mechanization, the compaction effect of tires on soil has become a matter of great concern. When agricultural machinery is operating in the field, the ground contact pressure of the tires may lead to a decrease in soil porosity and permeability, which in turn affects crop growth and soil ecosystems. In addition, soil compaction will increase the cost of farming and the uncertainty of crop yields. Traditional research has mainly focused on the effects of parameters such as tire load, width, and tire pressure on soil compaction. Summary of the invention

[0003] In order to solve the problem of how to reduce the adverse consequences of soil compaction, the present invention provides a method for detecting the degree of soil compaction by an agricultural tire.

[0004] A method for detecting the degree of soil compaction by an agricultural tire of the present invention comprises:

[0005] S1. Lay a pressure sensing film on the soil to be tested, press the tire on the pressure sensing film at a set roll angle, and count the pressure point positions and corresponding pressure values ​​on the pressure sensing film;

[0006] S2. Divide the pressure sensing film into three areas, namely, left area I, middle area II and right area III. Calculate the total pressure P of each area according to the pressure point distribution in each area. t , t=Ⅰ,Ⅱ,Ⅲ;

[0007] S3. According to the influence of the roll angle on the pressure in different regions, the pressure weights w of the three regions are obtained. Ⅰ ,w Ⅱ ,w Ⅲ , calculate the total pressure P corresponding to the roll angle D =P Ⅰ w Ⅰ +P Ⅱ w Ⅱ +P Ⅲ w Ⅲ ;

[0008] S4. According to S1 to S3, different roll angles θ are obtained. D The corresponding total pressure P D , D = 1, 2, ..., n, n represents the number of roll angles, according to different roll angles θ D The corresponding total pressure P D Calculate the total ground pressure P Z , w D is the roll angle θD The weight of influence;

[0009] S5, according to the total ground pressure P Z Calculate the total compaction C.

[0010] As a preference, in S2, the sum of the pressures in each region P t for:

[0011]

[0012] The coordinates of the pressure point position in the pressure sensing film area t are {(x1,y1),(x2,y2),...,(x m ,y m )}, corresponding to the pressure value area {P1, P2, ..., P m};

[0013] m is the number of pressure points generated by the tire within the pressure sensing film area t;

[0014] The geometric center coordinates of region t are (x c ,y c );

[0015] σ represents standard deviation.

[0016] As a preference, the three regional pressure weights w Ⅰ ,w Ⅱ ,w Ⅲ They are:

[0017]

[0018] Among them, the influence coefficient of the roll angle on the pressure distribution is

[0019] a0 and b0 are the major and minor axes of the tire contact patch when there is no roll, respectively;

[0020] W is the width of the tire;

[0021] D is the diameter of the tire.

[0022] As a preferred embodiment, in S4, the roll angle θ D The influence weight w D for:

[0023]

[0024] Here, ε is a small constant that prevents the denominator from being zero.

[0025] Preferably, the total compaction degree C is:

[0026]

[0027] Among them, M is the load and M0 is the standard load;

[0028] P is the tire pressure, P0 is the standard tire pressure;

[0029] v is the speed and v0 is the standard speed.

[0030] The beneficial effects of the present invention are that traditional research has only focused on the impact of factors such as tire width, load and inflation pressure on soil compaction effects, and has ignored the role of the important variable of roll angle. The present invention quantifies the impact mechanism of different tire roll angles (positive and negative angles) on ground pressure distribution and soil compaction. Traditional studies have difficulty capturing the asymmetric ground pressure distribution caused by changes in roll angles, and the present invention can collect pressure distribution data in real time with high precision. A quantitative model has been established for the changes in compaction depth caused by the roll angle, while traditional methods are mostly qualitative analysis. The present invention provides a quantitative basis for optimizing tire width, tire pressure and mechanical operating conditions. Application scenarios include soil protection operations of agricultural machinery under different terrain conditions, and load distribution optimization of engineering vehicles on special foundations. BRIEF DESCRIPTION OF THE DRAWINGS

[0031] Figure 1 It is a schematic diagram of the process of the present invention;

[0032] Figure 2 It is a regional schematic diagram of the pressure sensing film;

[0033] Figure 3 Schematic diagram of the major and minor axes of the tire contact patch when there is no roll. DETAILED DESCRIPTION

[0034] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0035] It should be noted that, in the absence of conflict, the embodiments of the present invention and the features in the embodiments may be combined with each other.

[0036] The present invention will be further described below in conjunction with the accompanying drawings and specific embodiments, but they are not intended to limit the present invention.

[0037] Traditional research only focuses on the impact of factors such as tire width, load and inflation pressure on soil compaction, ignoring the role of the important variable of roll angle. By introducing a pressure sensing film and a test bench, a set of ground contact pressure data in one of the three areas of the pressure sensing film (for example, the left area) is obtained by adjusting different tire roll angles. Then, all pressure data are weighted according to their different importance on the pressure sensing film and a regional total pressure is obtained using the Gaussian model. Figure 1 As shown, the method for detecting the degree of soil compaction by an agricultural tire of this embodiment includes:

[0038] Step 1. The detection method of this embodiment is carried out on a test bench, which includes a test bench and a tractor. A soil trough is provided on the test bench, and the soil to be tested is laid in the soil trough. A pressure sensing film is laid on the soil to be tested, and the roll angle of the tire is measured. The pressure sensing film is pressed to set the roll angle, and the tire of the tractor is controlled to walk on the soil trough, and the pressure point position and the corresponding pressure value on the pressure sensing film are counted:

[0039] Step 2: Divide the pressure sensing film into three areas, such as Figure 2 As shown, they are area I on the left, area II in the middle, and area III on the right:

[0040] Left area I: The low side area of ​​the lateral distribution of the contact patch, where pressure is concentrated at negative roll angles;

[0041] Middle area II: The center area of ​​the ground contact surface, where the ground contact pressure is usually more uniform;

[0042] Right area III: The high side area of ​​the lateral distribution of the contact patch, where the pressure may increase at positive roll angles;

[0043] Calculate the total pressure P of each area according to the pressure point distribution of each area t , t=Ⅰ,Ⅱ,Ⅲ:

[0044] A set of measurement data: {P1, P2, ..., P m}, represents the ground pressure values ​​at different positions in the area to the left of the pressure sensing film. These data are discrete pressure points. The position corresponding to each pressure point is: {(x1,y1),(x2,y2),...,(x m ,y m )}, indicating the spatial position of these pressure points on the pressure sensing film (expressed in horizontal and vertical coordinates).

[0045] The total pressure of each area P t for:

[0046]

[0047] The horizontal and vertical coordinates of the pressure point position of the pressure sensing film area t are {(x1,y1),(x2,y2),...,(x m ,y m )}, corresponding to the pressure value area {P1, P2, ..., P m};

[0048] m is the number of pressure points generated by the tire in the pressure sensing film area t; the horizontal and vertical coordinates of the geometric center of area t are (x c ,y c );σ represents the standard deviation. The horizontal and vertical directions of the geometric center of the region are (x c ,y c ) has the highest importance, and the farther away from the center point, the lower the importance. The parameter σ describing the degree of importance attenuation is taken as 0.98, which indicates the degree of diffusion of the Gaussian model.

[0049] Step 3: According to the influence of the roll angle on the pressure in different areas, the pressure weights w of the three areas are obtained. Ⅰ ,w Ⅱ ,w Ⅲ , calculate the total pressure P corresponding to the roll angle D =P Ⅰ w Ⅰ +P Ⅱ w Ⅱ +P Ⅲ w Ⅲ ;

[0050] Three area pressure weights w Ⅰ ,w Ⅱ ,w Ⅲ They are:

[0051]

[0052] w Ⅱ =1-|k·θ D |

[0053]

[0054] Among them, θ D is the tire roll angle (unit: °). When the tire rolls, θ D A positive value indicates that the vehicle body leans to the right, θ D Negative means leaning to the left.

[0055] The influence coefficient k of the roll angle on the pressure distribution is obtained by the following formula:

[0056]

[0057] a0 and b0 are the major and minor axes of the tire contact patch when there is no roll, respectively;

[0058] W is the width of the tire; D is the diameter of the tire.

[0059] Step 4: Follow steps 1 to 3 to obtain different roll angles θ D The corresponding total pressure P D , D = 1, 2, ..., n, n represents the number of roll angles, the smaller the roll angle, the greater the contribution, the roll angle θ D The influence weight w D for

[0060]

[0061] ε is a small constant to prevent the denominator from being zero, and is set to 0.01.

[0062] According to different roll angles θ D The corresponding total pressure P D Calculate the total ground pressure P Z , the integrated total ground pressure return formula:

[0063]

[0064] Step 5: According to the total ground pressure P Z Calculate the total compaction C:

[0065]

[0066] Among them, M is the load and M0 is the standard load;

[0067] For small tractor tires: 5,000-10.000N, M0 takes 7500N;

[0068] For medium-sized tractor tires: 10,000-30,000N, M0 takes 20,000N;

[0069] For large tractor tires: 30,000-60,000N, M0=45000N;

[0070] P is the tire pressure, P0 is the standard tire pressure;

[0071] v is the speed, v0 is the standard speed, and the benchmark value for field operations is 1m / s.

[0072] This embodiment uses experimental equipment and data analysis methods to evaluate the impact of tires on soil compaction under different roll angles, tire pressure, driving speed and other parameters. The ground contact pressure cloud map is obtained using the pressure sensing film, and the soil compaction degree is predicted in combination with mathematical modeling, thereby optimizing tire design and mechanical operating parameters.

[0073] This implementation method is based on a detection method using a pressure sensing film and a test bench. The tire ground contact pressure distribution data is collected in real time through a high-resolution pressure sensing film, and a set of compaction detection models are constructed in combination with mathematical modeling and experimental verification. In the agricultural field, the model can guide the adjustment of tire roll angles, load distribution, and operation mode optimization to achieve light compaction and high-efficiency operations, and reduce the damage to soil structure caused by inefficient repair methods such as deep plowing. In the engineering field, the model can also be used for construction foundation protection design to reduce the risk of settlement and instability. In the future, this technology is expected to be applied to multiple fields such as agriculture, engineering, and environmental protection, providing scientific support for green development and intelligent operations.

[0074] Although the present invention is described herein with reference to specific embodiments, it should be understood that these embodiments are merely examples of the principles and applications of the present invention. It should therefore be understood that many modifications may be made to the exemplary embodiments and that other arrangements may be devised without departing from the spirit and scope of the present invention as defined by the appended claims. It should be understood that the various dependent claims and features described herein may be combined in a manner different from that described in the original claims. It should also be understood that features described in conjunction with individual embodiments may be used in other described embodiments.

Claims

1. A method for detecting the degree of soil compaction by agricultural tires, characterized in that: The method comprises: S1. Lay a pressure sensing film on the soil to be tested, press the tire on the pressure sensing film at a set roll angle, and count the pressure point positions and corresponding pressure values ​​on the pressure sensing film; S2. Divide the pressure sensing film into three areas, namely, left area I, middle area II and right area III. Calculate the total pressure P of each area according to the pressure point distribution in each area. t , t=Ⅰ,Ⅱ,Ⅲ; S3. According to the influence of the roll angle on the pressure in different regions, the pressure weights w of the three regions are obtained. Ⅰ ,w Ⅱ ,w Ⅲ , calculate the total pressure P corresponding to the roll angle D =P Ⅰ w Ⅰ +P Ⅱ w Ⅱ +P Ⅲ w Ⅲ ; S4. According to S1 to S3, different roll angles θ are obtained. D The corresponding total pressure P D , D = 1, 2, ..., n, n represents the number of roll angles, according to different roll angles θ D The corresponding total pressure P D Calculate the total ground pressure P Z , w D is the roll angle θ D The weight of influence; S5, according to the total ground pressure P Z Calculate the total compaction C.

2. The method for detecting the degree of soil compaction by agricultural tires according to claim 1, characterized in that: In S2, the total pressure of each area P t for: The coordinates of the pressure point position in the pressure sensing film area t are {(x1,y1),(x2,y2),...,(x m ,y m )}, corresponding to the pressure value area {P1, P2, ..., P m }; m is the number of pressure points generated by the tire within the pressure sensing film area t; The geometric center coordinates of region t are (x c ,y c ); σ represents standard deviation.

3. The method for detecting the degree of soil compaction by agricultural tires according to claim 1, characterized in that: Three area pressure weights w Ⅰ ,w Ⅱ ,w Ⅲ They are: w Ⅱ =1-|k·θ D | Among them, the influence coefficient of the roll angle on the pressure distribution is a0 and b0 are the major and minor axes of the tire contact patch when there is no roll, respectively; W is the width of the tire; D is the diameter of the tire.

4. The method for detecting the degree of soil compaction by agricultural tires according to claim 1, characterized in that: In S4, the roll angle θ D The influence weight w D for: Here, ε is a small constant that prevents the denominator from being zero.

5. The method for detecting the degree of soil compaction by agricultural tires according to claim 1, characterized in that: The total compaction degree C is: Among them, M is the load and M0 is the standard load; P is the tire pressure, P0 is the standard tire pressure; v is the speed and v0 is the standard speed.

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