CN-121977562-A - Self-propelled sprayer field path planning method for soil mechanical compaction reduction

CN121977562ACN 121977562 ACN121977562 ACN 121977562ACN-121977562-A

Abstract

The invention belongs to the field of machinery, and particularly relates to a self-propelled sprayer field path planning method for soil mechanical compaction reduction. In order to solve the problem that the compaction degree of soil machinery is high in a path obtained by the existing path planning method, the invention provides a path planning method in a self-propelled sprayer field, a field operation area is planned by arranging a sensor in the self-propelled sprayer, and a soil mechanical model is built by detecting the compaction degree of the soil so as to improve a field path planning algorithm. The method not only reduces the soil compaction of the self-propelled sprayer to the greatest extent, but also provides a feasible path planning technical scheme on the basis of ensuring the efficiency of pesticide application operation, and solves the problem that the compaction degree of the path obtained by the existing path planning method to soil machinery is high.

Inventors

WANG YIJIA
LI GUOXU
WEN NUAN
LI TIANXIAO
FU QIANG
LI MO

Assignees

东北农业大学

Dates

Publication Date: 20260505
Application Date: 20260121

Claims (10)

1. The self-propelled sprayer field path planning method for the soil mechanical compaction reduction is characterized by comprising the following steps of: s1, scanning a soil area of a path to be planned by adopting a ground penetrating radar to obtain a radar signal; Performing signal preprocessing on the radar signal to obtain a preprocessed radar signal; s2, performing dielectric constant inversion processing according to the preprocessed radar signals to obtain a dielectric constant distribution diagram of a soil area of the path to be planned; s3, calculating soil body mechanical parameters according to a dielectric constant distribution diagram of a soil area of the path to be planned, wherein the soil body mechanical parameters comprise porosity, elastic modulus and internal friction angle; S4, constructing a soil stress field model by using a finite element method according to the soil mechanical parameters; S5, constructing a double-target optimization model according to the soil stress field model; S6, solving a double-target optimization model by using an improved ant colony algorithm to obtain a G path constructed by each ant, wherein G is a positive integer; And S7, screening the G paths constructed by each ant by using a Pareto front edge algorithm to obtain an optimal path.
2. The self-propelled sprayer field path planning method for soil mechanical compaction and reduction according to claim 1, wherein the method is characterized in that a ground penetrating radar is adopted to scan a soil area of a path to be planned in S1 to obtain radar signals, the radar signals are subjected to signal preprocessing to obtain preprocessed radar signals, and the specific process is as follows: S1.1, setting parameters of a ground penetrating radar; S1.2, scanning a soil area of a path to be planned by using a ground penetrating radar to obtain a radar signal ; S1.3 for radar signals Preprocessing to obtain preprocessed radar signals 。
3. The self-propelled sprayer in-field path planning method for soil mechanical compaction reduction of claim 2 wherein the radar signature is generated in S1.3 Preprocessing to obtain preprocessed radar signals The specific process is as follows: S1.3.1 pairs of radar signals Performing background removal processing to obtain a radar signal after background removal : S1.3.2 radar signal after background removal Performing band-pass filtering processing to obtain radar signals after the band-pass filtering processing : S1.3.3 band-pass filtering the processed radar signal Performing time-varying gain compensation processing to obtain a preprocessed radar signal 。
4. The self-propelled sprayer field path planning method for soil mechanical compaction and subtraction according to claim 3, wherein the step S2 is characterized in that the dielectric constant inversion processing is performed according to the preprocessed radar signal to obtain a dielectric constant distribution diagram of a soil area of a path to be planned, and the specific process is as follows: S2.1 for the preprocessed radar signals The hilbert transform process is performed and, according to the preprocessed radar signal after Hilbert transform processing Extracting signal envelope ; S2.2 according to signal envelope Locating reflected peak time ; S2.3 according to the time of reflection peak value Generating a dielectric constant profile of a soil region of a path to be planned 。
5. The self-propelled sprayer field path planning method for the compaction and subtraction of the soil machinery according to claim 4, wherein in the step S3, the soil mechanical parameters are calculated according to a dielectric constant distribution diagram of a soil area of a path to be planned, the soil mechanical parameters comprise porosity, elastic modulus and internal friction angle, and the specific process is as follows: s3.1, calculating the porosity n according to a dielectric constant distribution diagram of the soil area of the path to be planned, S3.2, calculating elastic modulus E according to the porosity n; S3.3, calculating an internal friction angle according to the dielectric constant distribution diagram and the porosity n of the soil area of the path to be planned 。
6. The self-propelled sprayer in-field path planning method for soil mechanical compaction reduction according to claim 5, wherein in the step S4, a soil stress field model is constructed by using a finite element method according to soil mechanical parameters; the specific process is as follows: S4.1, carrying out grid division on a soil area of a path to be planned to obtain a three-dimensional grid model, S4.2, constructing a rigidity matrix of each grid of the three-dimensional grid model according to the soil body mechanical parameters in the S4; Assembling a total stiffness matrix of the three-dimensional grid model according to the stiffness matrix of each grid of the three-dimensional grid model; And S4.3, constructing a soil stress field model according to the total stiffness matrix of the three-dimensional grid model, wherein the soil stress field model comprises a system static balance condition model, a stress calculation model and a plastic criterion model.
7. The self-propelled sprayer in-field path planning method for soil mechanical compaction and subtraction according to claim 6, wherein the step S5 is to construct a double-objective optimization model according to a soil stress field model, and the double-objective optimization model is expressed as: S5.1, constructing an objective function of a double-objective optimization model according to a soil stress field model, wherein the objective function is expressed as follows: In the formula, Representing the total rolling cost function The function P representing the total length of the path represents the selected path scheme, and e represents the single-row ordering of the jobs in the field; In the field for spraying machine the length of the operation single side; Is the stress of the grid w; the rolling times of the grid w; representing the total number of grids; S5.2, constructing constraint conditions of a double-target optimization model, wherein the constraint conditions comprise track coverage constraint, field ground steering constraint and operation speed constraint; the track coverage constraint is formulated as: The spraying machine coverage area is M represents an mth operation coverage area, M represents the total operation times, and F represents the total operation coverage area; the field head steering constraint is expressed as: The direction angle of the sprayer head at the moment t, The direction angle of the sprayer head at the time t-1 is shown; indicating the field maximum steering angle of the sprayer; The job speed constraint is formulated as: the operation speed of the sprayer at the time t is shown, Indicating the minimum operation speed of the sprayer; Indicating the maximum operating speed of the sprayer.
8. The self-propelled sprayer field path planning method for soil mechanical compaction and reduction according to claim 7, wherein the step S6 is characterized in that a double-objective optimization model is solved by using an improved ant colony algorithm to obtain a G path constructed by each ant, and the specific process is as follows: s6.1, initializing improved ant colony algorithm parameters, The improved ant colony algorithm parameters comprise ant colony number, pheromone volatilization coefficient, ant transfer probability and initial pheromone concentration matrix; Wherein, the first From the current grid of ants To a candidate grid The transition probability of (2) is formulated as: In the formula, For the heuristic function value of the current grid h to the candidate grid l, Is a weight factor of the pheromone, As heuristic weight factors, m represents an reachable grid sequence number; representing a current grid To a candidate grid Is used for the concentration of the pheromone, For the current grid Is used to determine the feasible neighborhood of (1), Wherein, heuristic function values from the current grid h to the candidate grid l are calculated The formula of (2) is: Wherein, the Heuristic variables are distance; Is a stress avoidance variable; Is a rolling inhibition variable; representing a current grid To a candidate grid Is the euclidean distance of (2); Representing the magnitude of the compressive stress of the current grid h to the candidate grid l, Representing the number of passes from the current grid h to the candidate grid l sprayer, S6.2, setting a pheromone concentration matrix updating rule, wherein the rule is expressed as follows by a formula: In the formula, Is a constant for the total amount of pheromones, As the path length weight of the path, Is the volatilization rate of the pheromone, As a coefficient of stress sensitivity, The update is represented by a representation of the update, Representing the cumulative compressive stress of ants arriving at grid l; s6.3, constructing a path of each ant according to the set algorithm parameters by each ant of the ant colony; According to the path of each ant, calculating the double objective function value of each ant; Updating the pheromone concentration matrix according to the double objective function value and the pheromone concentration matrix updating rule of each ant; s6.4, repeating the step S6.3, and stopping iteration when the iteration stopping condition is reached, so as to obtain G paths constructed by each ant, wherein G is a positive integer.
9. The self-propelled sprayer field path planning method for soil mechanical compaction and subtraction according to claim 8, wherein in S7, G paths constructed by each ant are screened by using Pareto front edge algorithm to obtain an optimal path, and the specific process is as follows: s7.1, taking each path constructed by each ant as a solution of the Pareto front-edge algorithm, and forming solution groups of the Pareto front-edge algorithm by all obtained solutions; S7.2, calculating an objective function value of each solution, and determining a dominant relationship among all solutions according to the objective function value of each solution; s7.3, selecting all non-dominant solutions for the dominant relations among all solutions, and adding the non-dominant solutions to the Pareto front; s7.4, judging whether the size of the Pareto front edge exceeds the limit, and eliminating the solution with the maximum crowding degree by using the crowding distance when the size of the Pareto front edge is larger than the limit; when the Pareto front edge size is smaller than or equal to the limit, outputting a solution of the Pareto front edge as an optimal solution, wherein a path corresponding to the optimal solution is an optimal path.
10. The self-propelled sprayer field path planning method for soil mechanical compaction and subtraction according to claim 8, wherein in the step S7.4, whether the Pareto front size exceeds the limit is judged, and when the Pareto front size is larger than the limit, a solution with the highest crowding degree is removed by using the crowding distance, and the specific process is as follows: the calculation formula for calculating the congestion distance of the ith solution is: In the formula, Representing the total rolling cost value of the i+1th solution, A path total length value representing the i+1th solution; represents the total rolling cost value of the i-1 th solution, A path total length value representing the i-1 th solution; Representing the maximum value of the total rolling cost, Represents the maximum value of the total length of the path; representing the minimum value of the total rolling cost, Representing the minimum total path length.

Description

Self-propelled sprayer field path planning method for soil mechanical compaction reduction Technical Field The invention belongs to the field of agricultural machinery dispatching, and particularly relates to a self-propelled sprayer field path planning method for soil mechanical compaction reduction. Background When modern agricultural machinery works in the field, repeated rolling of the soil by the wheels can cause the soil structure to change significantly. The change of the physical property not only prevents the normal extension and development of the root system of the crops, but also seriously influences the water penetration capacity of the soil, thereby restricting the water and nutrient absorption of the crops. The traditional self-propelled sprayer path planning only considers the operation efficiency, neglects the protection of the soil structure, and particularly in sensitive areas such as northeast black soil areas, the mechanical compaction is easy to cause crop yield reduction. Current solutions rely on a wide tire or crawler design to reduce the ground contact pressure but avoid cumulative damage to the deep soil. Therefore, the path obtained by the existing path planning method has the problem of high mechanical compaction degree of soil. Disclosure of Invention The invention aims to solve the problems that the existing path planning of the existing path planning has poor pertinence to soil compaction scenes in a field, and the error rate is high when an agricultural machinery operation task path is generated, so that the soil mechanical compaction degree is increased. The method for planning the field path of the self-propelled sprayer facing the soil mechanical compaction reduction comprises the following steps: s1, scanning a soil area of a path to be planned by adopting a ground penetrating radar to obtain a radar signal; Performing signal preprocessing on the radar signal to obtain a preprocessed radar signal; s2, performing dielectric constant inversion processing according to the preprocessed radar signals to obtain a dielectric constant distribution diagram of a soil area of the path to be planned; s3, calculating soil mechanical parameters according to a dielectric constant distribution diagram of a soil area of the path to be planned; The soil body mechanical parameters to be calculated comprise porosity, elastic modulus and internal friction angle; S4, constructing a soil stress field model by using a finite element method according to the soil mechanical parameters; S5, constructing a double-target optimization model according to the soil stress field model; S6, solving a double-target optimization model by using an improved ant colony algorithm to obtain a G path constructed by each ant, wherein G is a positive integer; And S7, screening the G paths constructed by each ant by using a Pareto front edge algorithm to obtain an optimal path. In the step S1, a ground penetrating radar is adopted to scan a soil area of a path to be planned to obtain a radar signal, the radar signal is subjected to signal preprocessing to obtain a preprocessed radar signal, and the specific process is as follows: S1.1, setting parameters of a ground penetrating radar; S1.2, scanning a soil area of a path to be planned by using a ground penetrating radar to obtain a radar signal ; S1.3 for radar signalsPreprocessing to obtain preprocessed radar signals; The S1.3 is used for radar signalsPreprocessing to obtain preprocessed radar signalsThe specific process is as follows: S1.3.1 pairs of radar signals Performing background removal processing to obtain a radar signal after background removal: S1.3.2 radar signal after background removalPerforming band-pass filtering processing to obtain radar signals after the band-pass filtering processing: S1.3.3 band-pass filtering the processed radar signalPerforming time-varying gain compensation processing to obtain a preprocessed radar signal。 In the step S2, dielectric constant inversion processing is carried out according to the preprocessed radar signals to obtain a dielectric constant distribution diagram of a soil area of a path to be planned, wherein the specific process comprises the following steps: S2.1 for the preprocessed radar signals The hilbert transform process is performed and, according to the preprocessed radar signal after Hilbert transform processingExtracting signal envelope; S2.2 according to signal envelopeLocating reflected peak time; S2.3 according to the time of reflection peak valueGenerating a dielectric constant profile of a soil region of a path to be planned。 In the step S3, calculating soil mechanical parameters according to a dielectric constant distribution diagram of a soil area of a path to be planned, wherein the soil mechanical parameters comprise porosity, elastic modulus and internal friction angle; the specific process is as follows: s3.1, calculating the porosity n according to a dielectric constant distribution diagram