A method and system for automatic delineation, navigation, and control of breeding experimental plots

Abstract

This invention relates to an automatic line marking and navigation control method and system for breeding experimental plots. The method includes the following steps: S1: Establishing a planar coordinate model of the experimental area; S2: Dividing the experimental plots based on the planar coordinate model and preset division parameters, generating theoretical line marking path segments for the experimental plots; S3: Generating a navigation task list for the automatic line marking vehicle based on the sorted theoretical line marking path segments, and navigating the automatic line marking vehicle according to the navigation task list; S4: During the automatic driving of the vehicle, the Stanley tracking algorithm is used to generate path tracking control for the automatic line marking vehicle. This invention realizes a complete closed-loop process from the acquisition of key point coordinates in the experimental area, plot parameter setting, path planning to unmanned vehicle navigation execution and pollination line marking completion, significantly improving the efficiency and accuracy of breeding plot line marking and reducing labor costs.

Description

Technical Field

[0001] This invention belongs to the field of agricultural equipment navigation technology, and in particular relates to an automatic line marking navigation control method and system for breeding experimental plots. Background Technology

[0002] The precise delineation of breeding experimental plots is a fundamental step in ensuring the reliability and comparability of experimental data in agricultural breeding experiments. Currently, this work mainly relies on manual labor. Typically, workers measure the side lengths and plot dimensions manually using tape measures or measuring tapes according to the experimental design plan, mark the points with wooden stakes or bamboo sticks, and then use string lines or ropes to determine the plot boundaries. Finally, white lime powder is manually applied along the lines to form ground markings. This manual marking method has the following significant drawbacks:

[0003] (1) The work efficiency is low and the labor intensity is high. The entire process of marking lines requires repeated measurement, line pulling and powdering. When facing large-scale tests of hundreds or thousands of communities, a lot of manpower and time are required.

[0004] (2) The accuracy and consistency of the marking are difficult to guarantee. Manual operation is easily affected by experience, line of sight and ground undulation, which leads to errors in the size, spacing and alignment of the plots, which impairs the spatial consistency and data reliability of the test.

[0005] (3) Low standardization and over-reliance on individual experience. Different operators have large differences in operation, making it difficult to form a unified and replicable standardized process, which is not conducive to large-scale promotion and continuous years of trials.

[0006] Furthermore, because modern breeding experimental fields are typically small in scale, numerous, and densely laid out with regular patterns, this operational scenario places high demands on the positioning accuracy, path planning capabilities, and precision of the actuators of automated equipment. Currently, general-purpose automated guided vehicles used in sowing, spraying, and other processes often lack the navigation accuracy and operational modes to meet the needs of dense, reciprocating straight-line marking, and therefore cannot directly achieve precise and efficient automated operations in the division of breeding experimental plots. Summary of the Invention

[0007] The purpose of this invention is to solve one of the above-mentioned technical problems and to provide an automatic line marking and navigation control method and system for breeding experimental plots.

[0008] To achieve the above objectives, the technical solution adopted by the present invention is as follows:

[0009] A method for automatic demarcation and navigation control of breeding experimental plots includes the following steps:

[0010] S1: Collect the latitude and longitude coordinates of the four corner points of the breeding test area; establish a planar coordinate model of the test area based on the latitude and longitude coordinates of the four corner points;

[0011] S2: Set the division parameters for the test cells; divide the test cells based on the plane coordinate model and division parameters, and generate cell grid lines;

[0012] The grid lines of the test community are used as the theoretical line-drawing path segments. The direction of each theoretical line-drawing path segment is determined according to the predetermined rules, and the theoretical line-drawing path segments are sorted.

[0013] S3: Generate a navigation task list for the automatic line marking vehicle based on the sorted theoretical line marking path segments, and navigate the automatic line marking vehicle according to the navigation task list so that it can drive automatically in the breeding test area, and control the powder spreading mechanism mounted on the automatic line marking vehicle to spread powder and mark the line.

[0014] S4: During the vehicle's automatic driving process, the vehicle's current latitude and longitude information and the vehicle's current heading angle information are acquired in real time. Based on the vehicle's current latitude and longitude information and the vehicle's heading angle information, the lateral error and heading error between the vehicle's current position and the theoretical line segment it is currently traveling on are calculated. Based on the lateral error and heading error, the Stanley tracking algorithm is used to generate steering control values ​​for the wheels of the automatically marked vehicle. Based on the steering control values, the speed of the left and right drive wheels of the automatically marked vehicle is adjusted so that the vehicle runs along the current theoretical line segment.

[0015] In some embodiments of the present invention, step S1: the method for establishing a planar coordinate model of the test area includes the following steps:

[0016] Select one corner point of the test area as the origin corner point;

[0017] The latitude and longitude coordinates of the test area are transformed into a Cartesian coordinate system with the origin and corner points as the origin by using a predetermined planar coordinate approximation transformation formula;

[0018] The predetermined approximate transformation formula for plane coordinates is:

[0019] ;

[0020] ;

[0021] Where x is the abscissa of the Cartesian coordinate system, and y is the ordinate of the Cartesian coordinate system. The longitude of the origin's corner point. The latitude of the origin and corner point. The longitude of any point in the test area. Let latitude be any point in the test area. This is the scaling factor for converting latitude and longitude differences into meters.

[0022] In some embodiments of the present invention, step S2 specifically includes the following steps:

[0023] The long and short directions of the test area are determined based on the planar coordinates of the four corner points of the test area in the planar coordinate model.

[0024] Equidistant interpolation is performed along the long and short sides based on the division parameters to generate cell grid lines; the cell grid lines are either cell boundary lines or cell center lines.

[0025] The grid lines of the test community are used as the theoretical line-drawing path segments. The direction of each theoretical line-drawing path segment is determined according to the predetermined rules, and the theoretical line-drawing path segments are sorted.

[0026] Based on the lateral offset distance between the nozzle of the powder spreading mechanism mounted on the automatic marking vehicle and the geometric center of the vehicle, offset compensation is performed on each theoretical marking path segment.

[0027] In some embodiments of the present invention, step S3, the method for navigating automatically marked routes for vehicles based on a navigation task list, specifically includes:

[0028] Each theoretical line segment after offset compensation is discretized into path points, and an ordered sequence of path points is generated.

[0029] Generate a task for each path point in the ordered path point sequence to obtain a navigation task list; wherein, each path point's task includes the path point's task number, the path point's target coordinates, and the current task status;

[0030] The automatic lane marking vehicle is controlled to execute the tasks of each path point in the navigation task list in sequence, so that the automatic lane marking vehicle can drive automatically along each theoretical lane marking path segment in the test area.

[0031] In some embodiments of the present invention, step S4 specifically includes the following steps:

[0032] During the task execution, the starting and ending coordinates of the theoretical line-marking path segment currently being traveled by the automatically marked vehicle, the vehicle's current latitude and longitude information, and the vehicle's current heading angle information are obtained in real time.

[0033] The distance d between the vehicle's current position and the end point of the theoretically marked path segment is calculated based on the coordinates of the end point of the theoretically marked path segment and the vehicle's current latitude and longitude information.

[0034] If the distance d is less than the predetermined distance threshold, the task index of the theoretical line drawing path segment currently being traveled by the vehicle has been completed, and the task index of the next theoretical line drawing path segment continues to be executed.

[0035] Otherwise, based on the starting and ending coordinates of the currently traveled theoretical route segment and the theoretical heading angle of the currently traveled theoretical route segment, the following is determined: ,

[0036] Calculate the heading error between the vehicle's current heading and the target heading based on the vehicle's current heading angle information. ;

[0037] If heading error If the deviation exceeds the predetermined steering threshold, the automatically marked lane vehicle will be controlled to turn in place until the heading error is corrected. The absolute value is less than the predetermined steering threshold;

[0038] Otherwise, calculate the lateral error between the vehicle's current position and the theoretically marked path segment the vehicle is currently traveling on. And based on lateral error With heading error Calculate the overall error Then, the Stanley tracking algorithm is used to integrate the error. The signal is converted into a PWM signal for the wheel drive motor through linear mapping, forming the steering control quantity of the wheel, so that the vehicle can track and run along the sorted theoretically marked path segments.

[0039] In some embodiments of the present invention, step S4, the method for generating steering control values ​​for the wheels of an automatically lane-marking vehicle using the Stanley tracking algorithm, specifically includes the following steps:

[0040] For lateral error Nonlinear compression is performed, and the compression formula is:

[0041] ;

[0042] in, To account for the lateral error after nonlinear compression, The distance between the current projection point and the next path point. For lateral error gain;

[0043] Lateral error after nonlinear compression and heading error Amplitude limiting is applied, and the overall error is calculated. :

[0044] ;

[0045] in, and All are proportionality coefficients, and the overall error is... The amplitude is limited to Within the range;

[0046] Comprehensive error By linearly mapping and converting the PWM differential signals of the left and right drive wheels of the automatically marked vehicle, the PWM signals of the wheel drive motors are generated, which in turn generate the steering control quantities of the wheels, enabling the vehicle to track and run along the sorted theoretical marked path segments.

[0047] In some embodiments of the present invention, the following steps are further included:

[0048] During autonomous driving, when the automatically marked vehicle transitions from the previous theoretically marked path segment to the starting point of the next theoretically marked path segment, the target direction angle is calculated based on the vehicle's current coordinates and the starting coordinates of the next theoretically marked path segment. ;

[0049] Control the vehicle to turn in place until the target steering angle is reached. With respect to the vehicle's current heading angle When the difference is less than the predetermined heading difference threshold, the vehicle body alignment is completed;

[0050] After the vehicle body is aligned, the straight-line marking stage begins. A PID controller processes the heading error using proportional, integral, and derivative operations to calculate the steering correction. :

[0051] ;

[0052] in, For heading error, , , , These are the proportional, integral, and differential coefficients of the heading error, respectively.

[0053] During vehicle driving, the basic forward PWM is denoted as The calculated PWM signals for the left and right wheels are as follows:

[0054] ;

[0055] ;

[0056] in, This is the PWM signal for the left wheel. This is the PWM signal for the right wheel.

[0057] In some embodiments of the present invention, step S3 further includes the following steps:

[0058] Configure the operating mode state machine of the automatic line marking vehicle; the operating modes include at least idle mode, manual mode and automatic mode; in idle mode, the drive motor and powder spreading mechanism of the automatic line marking vehicle are turned off; in manual mode, the operation and powder spreading of the automatic line marking vehicle are controlled by manual commands; in automatic mode, the navigation task list is called and executed, the vehicle is driven and the powder spreading is automatically controlled.

[0059] The scheduled task processing function is set to read the current running mode at predetermined intervals and switch the state machine according to the interaction status between the user and the host computer based on manual commands.

[0060] In some embodiments of the present invention, step S3, the method of controlling the powder-spreading mechanism mounted on the automatic line-marking vehicle to spread powder and mark lines includes the following steps:

[0061] When the automatic marking vehicle travels on each theoretical marking path segment, the lime powder mixing and feeding mechanism of the vehicle is controlled to run at the set speed to achieve continuous and uniform spreading of lime powder along the path; when the path execution ends or an abnormality occurs, the spreading mechanism is automatically stopped.

[0062] Some embodiments of the present invention further provide an automatic demarcation and navigation control system for breeding experimental plots, used to execute the above-described automatic demarcation and navigation control method for breeding experimental plots, including:

[0063] Automatic lane marking vehicle, including a walking actuator and a powder spreading mechanism:

[0064] The RTK positioning module, including a fixed base station and a mobile positioning terminal, is used to provide real-time positioning and orientation data for automated lane marking vehicles.

[0065] The human-computer interaction module is used to collect the coordinates of the corner points of the test area and the division parameters of the test sub-areas input by the user, and to display the system status;

[0066] The main control board module communicates with the RTK positioning module and the human-machine interaction module. It is used to perform test area modeling, automatic cell division, operation path planning and generate a navigation task list based on corner coordinates and cell division parameters. It performs path tracking calculation based on real-time positioning data and navigation task list to generate driving control commands and powder spreading control commands.

[0067] The traveling actuator control module, connected to the main control board module, is used to receive driving control commands and drive the automatic lane marking vehicle to move through the traveling actuator.

[0068] The powder spreading control module, connected to the main control board module, is used to receive powder spreading control commands and control the mixing and feeding of the marking material in the powder spreading mechanism, so as to spread powder on the ground synchronously during the movement of the automatic marking vehicle.

[0069] In some embodiments of the present invention, the main control board module is configured to run a state machine, which includes at least an idle mode, a manual mode, and an automatic mode. In the automatic mode, the main control board module calls the navigation task list and automatically controls the walking actuator control module and the powder spreading control module to work together.

[0070] The beneficial effects of this invention are as follows:

[0071] 1. The automatic line marking navigation control method provided by the present invention only requires manual collection of the four corner points of the test area and setting of the division parameters. It can automatically complete the area modeling, small area division and navigation and powder spreading operations of the automatic line marking vehicle, replacing the traditional repeated distance measurement, line drawing and manual powder spreading, greatly shortening the operation time and significantly reducing on-site manpower input and labor intensity.

[0072] 2. This invention uses centimeter-level position and heading information provided by RTK differential positioning technology and Stanley for path tracking control, enabling the automatic line marking vehicle to run precisely along the predetermined planned path, which greatly improves the accuracy, consistency and quality of line marking, and reduces the waste of lime powder, such as missed spreading, double spreading and white lime powder.

[0073] 3. This invention solidifies corner point acquisition, cell division, path generation, navigation tracking, and dusting control into algorithms and a running state machine. Combined with the menu-driven settings of the handheld device, operators can complete high-quality line drawing by setting parameters and starting the operation step by step, significantly reducing reliance on experienced technicians. At the same time, different operating modes and safety mechanisms are designed. In the event of communication abnormalities or misoperation, the system can automatically stop and shut down dusting, improving the overall operational safety and reliability.

[0074] 4. While forming physical lines in the field, this invention retains the latitude and longitude coordinates and task information corresponding to each line and each plot, forming plot layout data under a unified coordinate system. Compared with the traditional manual line marking that relies solely on visual identification, it can provide a unified spatial benchmark for subsequent positioning sampling, drone patrol, automatic harvesting path planning, and experimental data spatial management.

[0075] 5. The automatic line marking navigation control method provided by this invention supports multiple modes of dividing plots, such as dividing along different sides, configuring by row spacing / column spacing, or configuring by the number of rows and columns. It can adapt to breeding experimental fields with different areas, shapes, and layouts and has good adaptability.

[0076] Other features and advantages of the invention will be set forth in the description which follows, and will be apparent in part from the description, or may be learned by practicing the invention. The objects and other advantages of the invention may be realized and obtained by means of the structures pointed out in the description, claims and drawings. Attached Figure Description

[0077] To more clearly illustrate the technical solutions in the embodiments of this application or the prior art, the specific embodiments of the present invention will be described in detail below with reference to the accompanying drawings. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0078] Figure 1 A flowchart of an automatic delineation and navigation control method for breeding experimental plots;

[0079] Figure 2 A flowchart illustrating the overall control method provided in this embodiment of the invention;

[0080] Figure 3 This is an overall flowchart of the cell division and line drawing path generation method provided in an embodiment of the present invention;

[0081] Figure 4 This is an overall flowchart of the path navigation and tracking method provided in the embodiments of the present invention;

[0082] Figure 5 A schematic diagram of an automatic line marking and navigation control system for breeding experimental plots;

[0083] Figure 6 Signal flow diagram of the navigation control system provided in the embodiments of the present invention;

[0084] Figure 7 This is a schematic diagram of the structure of an automatic lane marking vehicle provided in an embodiment of the present invention;

[0085] Figure 8 This is a schematic diagram of the material feeding control power supply assembly provided in an embodiment of the present invention;

[0086] Figure 9 This is a schematic diagram of the powder-spreading module provided in an embodiment of the present invention;

[0087] The attached figures are labeled as follows:

[0088] 1. Tracked walking assembly;

[0089] 2. Material feeding control power supply assembly; 21. Power supply module; 22. Powder spreading mechanism; 221. Feeding funnel; 222. Motor commutator; 223. Powder spreading drive motor; 224. Drive shaft sleeve; 225. Stirring rod seat; 226. Stirring rod; 227. Connecting buckle; 228. Feeding cylinder; 229. Feeding screw; 2210. Coupling; 2211. Stirring rod; 2212. Conical hopper; 2213. Feeder cover 2214. Drive shaft; 23. Main control board and power safety management module; 231. Motor driver; 232. Air switch; 233. Power management control board; 234. Emergency stop switch; 235. Power charging port; 236. Rear protection board; 237. Main control box; 3. Real-time positioning status assembly; 31. Front receiver; 32. Rear receiver; 33. Front antenna; 34. Rear antenna; 35. Status indicator light. Detailed Implementation

[0090] To make the objectives, technical solutions, and advantages of this application clearer, the application is described and illustrated below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative and not intended to limit the scope of this application. All other embodiments obtained by those skilled in the art based on the embodiments provided in this application without inventive effort are within the scope of protection of this application.

[0091] It should be noted that the terminology used herein is for the purpose of describing particular implementations only and is not intended to limit the exemplary implementations according to this application. As used herein, unless the context clearly indicates otherwise, the singular form is also intended to include the plural form. Furthermore, it should be understood that the terms “comprising” and “having”, and any variations thereof, are intended to cover non-exclusive inclusion, for example, a process, method, system, product, or apparatus that comprises a series of steps or units is not necessarily limited to those steps or units explicitly listed, but may include other steps or units not explicitly listed or inherent to such process, method, product, or apparatus.

[0092] Where there is no conflict, the embodiments and features in the embodiments of the present invention can be combined with each other.

[0093] The technical solution of the present invention will be described in detail below with reference to specific embodiments and accompanying drawings.

[0094] As attached Figure 1 - Appendix Figure 9As shown in the illustrative embodiment of an automatic line marking navigation control method for breeding experimental plots according to the present invention, this navigation control method is used to drive an automatic line marking vehicle equipped with a powdering mechanism through a corresponding automatic line marking navigation control system, enabling it to automatically travel and mark lines within the breeding experimental area. The navigation control method includes the following steps.

[0095] S1: The latitude and longitude coordinates of the four corner points of the breeding test area are collected using an RTK positioning device and sent to the main control board of the control system. The main control board establishes a planar coordinate model of the test area based on the latitude and longitude coordinates of the four corner points. The RTK positioning device includes at least a fixed base station and a mobile positioning terminal. The fixed base station is fixed at a fixed location near the breeding test area, and the mobile positioning terminal is installed on the body of the automatic line marking vehicle.

[0096] In step S1, the method for collecting the latitude and longitude coordinates of the four corner points of the breeding test area specifically includes the following steps.

[0097] Operators use portable handheld controllers to park sequentially at the four corner points of the rectangular area along the boundary of the experimental field. They then trigger data acquisition commands sequentially using the handheld controllers to record the latitude and longitude coordinates of each corner point. After data acquisition, the corner point coordinates are reported to the main control board of the control system via wireless communication and cached for subsequent cell division and trajectory generation.

[0098] In some embodiments of the present invention, such as Figure 2 As shown, before collecting the latitude and longitude coordinates of the four corner points of the breeding test area using the RTK positioning device in step S1, the following steps are further included.

[0099] The fixed base station is activated to initialize and broadcast the base station coordinates; the RTK receiver on the automatic line marking vehicle receives differential data from the base station and BeiDou satellite observation information, and enters the centimeter-level RTK positioning state.

[0100] In some embodiments of the present invention, the method for establishing a planar coordinate model of the test area in step S1 includes the following steps.

[0101] One corner of the test area was selected as the origin corner point.

[0102] The latitude and longitude coordinates of the test area are transformed into a Cartesian coordinate system with the origin and corner points as the origin by using a predetermined plane coordinate approximation transformation formula.

[0103] The predetermined approximate transformation formula for plane coordinates is:

[0104] ;

[0105] .

[0106] Where x is the abscissa of the Cartesian coordinate system, and y is the ordinate of the Cartesian coordinate system. The longitude of the origin's corner point. The latitude of the origin and corner point. The longitude of any point in the test area. Let latitude be any point in the test area. To convert latitude and longitude differences into meters, .

[0107] Through the above transformation, the boundary line of the rectangular test area and the line segments of the internal cells can be represented by planar straight line segments, which facilitates the subsequent calculation of geometric quantities such as distance and offset.

[0108] S2: Set the division parameters and line marking patterns for the test plots, forming a set of division parameters, and send it to the main control board of the control system. The division parameters for the test plots are input through the human-machine interface of the handheld device, including one or more of the following: row and column spacing, number of plots, and number of rows and columns. Line marking patterns include serpentine pattern and unidirectional movement pattern.

[0109] The test cells are divided based on a planar coordinate model and partitioning parameters, generating cell grid lines. These grid lines serve as the boundary lines, center lines, or reference lines for applying powder to each cell.

[0110] The grid lines of the test area are used as the theoretical line-drawing path segments. The direction of each theoretical line-drawing path segment is determined according to predetermined rules, and the segments are sorted. To avoid the lines from left to right intersecting, the system also judges the path order and performs necessary reversal processing to ensure that the travel path is arranged in the shape corresponding to the line-drawing pattern.

[0111] In some embodiments of the present invention, such as Figure 3 As shown, step S2 specifically includes the following steps.

[0112] The long and short sides of the test area are determined based on the planar coordinates of the four corner points of the rectangular test area in the planar coordinate model.

[0113] Cell grid lines are generated by equidistant interpolation along the long and short sides based on the division parameters. The cell grid lines are either cell boundary lines or cell center lines.

[0114] The grid lines of the test area are used as the theoretical line segments. The direction of each theoretical line segment is determined according to predetermined rules, and the segments are then sorted. In this embodiment, the line marking pattern is a back-and-forth serpentine pattern. To ensure that the vehicle's direction of travel is consistent with the serpentine logic, the paths are arranged in a back-and-forth serpentine manner during the sorting process. Odd-numbered rows are from left to right, and even-numbered rows are from right to left. The sign of the cross product between the diagonal vector of the test area and the first line vector is determined. If the result shows that the current path direction is opposite to the expected direction, the task list is reversed to ensure that the path order is consistent with the plot layout.

[0115] Based on the lateral offset distance between the nozzle of the powder spreading mechanism mounted on the automatic marking vehicle and the geometric center of the vehicle, offset compensation is performed on each theoretical marking path segment to make the actual powder spreading trajectory of the powder spreading mechanism coincide with the theoretical marking path segment.

[0116] The method for offset compensation includes the following steps.

[0117] Let the endpoints of a line segment in a plane coordinate system be... and The direction vector of the line segment is Its length is:

[0118] .

[0119] The unit vector is:

[0120] .

[0121] If the offset distance of the nozzle relative to the center line of the vehicle body is Then offset the rear endpoint The coordinates are:

[0122] ;

[0123] .

[0124] S3: As Figures 3-4 As shown, a navigation task list for the automatic line marking vehicle is generated based on the sorted theoretical line marking path segments. The automatic line marking vehicle is then guided to navigate the path based on the navigation task list, enabling it to drive automatically in the breeding test area. The powder spreading mechanism mounted on the automatic line marking vehicle is also controlled to spread powder and mark the lines.

[0125] In some embodiments of the present invention, step S3, the method for navigating automatically marked vehicles based on a navigation task list, specifically includes the following steps.

[0126] Each theoretically drawn path segment after offset compensation is discretized into path points, and an ordered sequence of path points is generated.

[0127] Generate a task for each pathpoint in the ordered pathpoint sequence to obtain a navigation task list; wherein, each pathpoint task includes the task number of the pathpoint, the target coordinates of the pathpoint, and the current task status.

[0128] The automatic lane marking vehicle is controlled to execute the tasks of each path point in the navigation task list in sequence, so that the automatic lane marking vehicle can drive automatically along each theoretical lane marking path segment in the test area.

[0129] In some embodiments of the present invention, the following steps are further included.

[0130] Based on the offset-compensated path points, a task list array is generated, and the latitude and longitude coordinates of each target point are added sequentially. The coordinates of the first point are then appended to the end of the list to form a closed path that facilitates the vehicle's return to the starting point.

[0131] In some embodiments of the present invention, step S3, the method of controlling the powder spreading mechanism mounted on the automatic marking vehicle to spread powder and mark lines specifically includes the following steps.

[0132] Configure the operating mode state machine for the automatically marking vehicle. The operating modes include idle mode (MOBILED_IDLE), manual mode (MOBILED_Manual), and automatic mode (MOBILED_AUTO). In idle mode, the motor and powder spreading mechanism are off. In manual mode, forward, reverse, left turn, right turn, and powder spreading are directly controlled according to the handheld device commands. In automatic mode, the task list execution function is called to drive the vehicle and automatically control powder spreading according to the path planning results.

[0133] Set a timed task processing function to read the current running mode every 100ms and switch the state machine according to the operator's commands and the interaction status with the host computer.

[0134] The drive system employs interlocking and safety checks to interlock and determine forward, reverse, and left / right steering commands, preventing erroneous control states such as "both forward and reverse are effective simultaneously" or "both left and right are effective simultaneously." Only when the operating mode is not idle does it generate valid forward, reverse, and left / right steering control signals for the motor based on the current direction command (FWD_REV) and steering command (Left_Right), along with speed and powder-spreading motor speed commands.

[0135] In the automatic mode, when the automatic running status is marked as "running" and the current path task is in "execution", the lime powder mixing and feeding motors are controlled to run at the set speed. When the task is paused, ended, or communication is abnormal, the powder spreading motors stop immediately to prevent excessive spreading and idling waste.

[0136] In some embodiments of the present invention, step S3, the method of controlling the powder spreading mechanism mounted on the automatic marking vehicle to spread powder and mark lines includes the following steps.

[0137] When the automatic marking vehicle travels on the theoretical marking path segments, that is, when the control system is in automatic operation and the current state is marking execution, the lime powder mixing and feeding mechanism of the vehicle operates at a set speed to achieve continuous and uniform spreading of lime powder along the path. When the path execution ends or is paused / abnormal, the powder spreading mechanism automatically stops.

[0138] S4: During the vehicle's automatic driving process, the vehicle's current latitude and longitude information and the vehicle's current heading angle information are acquired in real time. Based on the vehicle's current latitude and longitude information and the vehicle's heading angle information, the lateral error and heading error between the vehicle's current position and the theoretical line segment it is currently traveling on are calculated. Based on the lateral error and heading error, the Stanley tracking algorithm is used to generate steering control values ​​for the wheels of the automatically marked vehicle. Based on the steering control values, the speed of the left and right drive wheels of the automatically marked vehicle is adjusted so that the vehicle runs along the current theoretical line segment.

[0139] In some embodiments of the present invention, step S4 specifically includes the following steps:

[0140] During the task execution, the starting and ending coordinates of the theoretical line-marking path segment currently being traveled by the automatically marked vehicle, the vehicle's current latitude and longitude information, and the vehicle's current heading angle information are obtained in real time.

[0141] Calculate the straight-line distance d between the vehicle's current position and the end point of the theoretically marked path segment based on the coordinates of the vehicle's current destination and the vehicle's current latitude and longitude information.

[0142] If the distance d is less than the predetermined distance threshold, the task indexing of the theoretical line-drawing path segment currently being traveled by the vehicle has been completed, and the task indexing of the next theoretical line-drawing path segment continues to be executed.

[0143] Otherwise, based on the starting and ending coordinates of the currently traveled theoretical route segment and the theoretical heading angle of the currently traveled theoretical route segment, the following is determined: .

[0144] Calculate the heading error between the vehicle's current heading and the target heading based on the vehicle's current heading angle information. .

[0145] If heading error If the deviation exceeds the predetermined steering threshold, the automatically marked lane vehicle will be controlled to turn in place until the heading error is corrected. The absolute value is less than the predetermined steering threshold.

[0146] Otherwise, calculate the lateral error between the vehicle's current position and the theoretically marked path segment the vehicle is currently traveling on. And based on lateral error With heading error Calculate the overall error Then, the Stanley tracking algorithm is used to integrate the error. The signal is converted into a PWM signal for the wheel drive motor through linear mapping, forming the steering control quantity of the wheel, so that the vehicle can track and run along the sorted theoretically marked path segments.

[0147] To achieve accurate vehicle tracking along the target line, the signed distance from the point to the line is used as the lateral error. The specific calculation method is as follows:

[0148] Suppose that a target straight line segment on the current path originates from point... and The current vehicle location is defined as follows: First, transform the three points to a planar coordinate system with the first point of the task list as the origin. , , ,definition:

[0149] ;

[0150] Calculate the lateral error for:

[0151] ;

[0152] when This indicates that the vehicle is located on the left side of the path. This indicates that it is located on the right side of the path.

[0153] Heading error The specific calculation method is as follows:

[0154] The theoretical heading angle corresponding to the current path line AB is: The heading is calculated using the classical spherical heading formula based on the current vehicle position and the coordinates of the next target point. Let the latitude and longitude of the two points be converted to radians as follows: and Longitude difference is ,but:

[0155] ;

[0156] To ensure the results are in Within the scope, Normalized to:

[0157] .

[0158] The actual heading angle of the vehicle body is To avoid discontinuities caused by angles crossing 0° / 360°, the heading error will be... Normalization to Within the interval:

[0159] .

[0160] like ,but ;like ,but .

[0161] straight-line distance The following approximate distance formula is used for calculation:

[0162] ;

[0163] ;

[0164] ;

[0165] in, The coordinates of the vehicle's current location. The coordinates of the target point, The unit is m.

[0166] After calculating the lateral error and heading error Then, the control law is constructed by introducing the comprehensive steering error of the Stanley algorithm.

[0167] In some embodiments of the present invention, step S4, which uses the Stanley tracking algorithm to generate steering control values ​​for the wheels of an automatically lane-marked vehicle, specifically includes the following steps.

[0168] For lateral error Nonlinear compression is performed, and the compression formula is:

[0169] .

[0170] in, To account for the lateral error after nonlinear compression, The distance between the current projection point and the next path point. This is the lateral error gain.

[0171] Lateral error after nonlinear compression and heading error Amplitude limiting is applied, and the overall error is calculated. :

[0172] .

[0173] in, and All are proportionality coefficients, and the overall error is... The amplitude is limited to Within the range.

[0174] Comprehensive error By linearly mapping and converting the PWM differential signals of the left and right drive wheels of the automatically marked vehicle, the PWM signals of the wheel drive motors are generated, which in turn generate the steering control quantities of the wheels, enabling the vehicle to track and run along the sorted theoretical marked path segments.

[0175] In some embodiments of the present invention, during the automatic driving process, when the automatically marked vehicle turns from the starting point of the previous theoretical marked path segment to the next theoretical marked path segment, if the current vehicle heading deviates significantly from the target heading, for example, by more than 3°, a two-step strategy of "turning in place and then going straight" is adopted. This strategy specifically includes the following steps.

[0176] Calculate the target direction angle based on the vehicle's current coordinates and the starting coordinates of the next theoretically defined path segment. .

[0177] Control the vehicle to turn in place until the target steering angle is reached. With respect to the vehicle's current heading angle When the difference is less than the predetermined heading difference threshold, the vehicle body alignment is completed. When the vehicle is rotating in place, it will turn right or left in the shortest direction of rotation.

[0178] After the vehicle body is aligned, the straight-line marking stage begins. A PID controller processes the heading error using proportional, integral, and derivative operations to calculate the steering correction. :

[0179] .

[0180] in, For heading error, , , , These are the proportional, integral, and differential coefficients of the heading error, respectively.

[0181] During vehicle driving, the basic forward PWM is denoted as The calculated PWM signals for the left and right wheels are as follows:

[0182] ;

[0183] .

[0184] in, This is the PWM signal for the left wheel. For the right wheel PWM signal, Implement upper and lower limit constraints, and dynamically adjust the base speed based on the vehicle's distance from the target point; for example, reduce the speed as the vehicle approaches the target point. This ensures accuracy while improving operational stability.

[0185] In some embodiments of the present invention, the following steps are further included.

[0186] Once all navigation marking tasks are completed or the operator issues an end command, the automatic marking device stops moving and spreading, and switches the state machine to idle mode, waiting for the next marking task.

[0187] As attached Figure 5 - Appendix Figure 9 As shown, some embodiments of the present invention further provide an automatic line marking and navigation control system for breeding experimental plots, used to control an automatic line marking vehicle to execute the above-described automatic line marking and navigation control method for breeding experimental plots. The automatic line marking vehicle includes at least a walking actuator and a powder spreading mechanism 22. The system includes an RTK positioning module, a human-machine interface module, a main control board module, a walking actuator control module, a powder spreading execution control module, a communication module, and a power supply and safety protection module.

[0188] The RTK positioning module includes a fixed base station and a mobile positioning terminal, which are used to provide real-time positioning and orientation data for automated lane marking vehicles.

[0189] The human-computer interaction module is a portable handheld device used to collect the corner coordinates of the test area and the division parameters of the test sub-area input by the user, and to display the system status.

[0190] The main control board module communicates with the RTK positioning module and the human-machine interaction module. It is used to perform test area modeling, automatic cell division, operation path planning and generate a navigation task list based on corner coordinates and cell division parameters. Based on real-time positioning data and the navigation task list, it performs path tracking calculation and generates driving control commands and powder spreading control commands.

[0191] The traveling actuator control module is connected to the main control board module and is used to receive driving control commands and drive the automatic lane marking vehicle to move through the traveling actuator.

[0192] The powder spreading execution control module is connected to the main control board module and is used to receive powder spreading control commands and control the mixing and feeding of the marking material in the powder spreading mechanism so as to spread powder on the ground synchronously during the movement of the automatic marking vehicle.

[0193] The inter-module connections and signal flow in this system are as follows: Figure 6 As shown, the fixed base station is installed at a fixed location near the work area. It receives satellite navigation signals through a satellite antenna, calculates differential correction information in real time using a built-in differential calculation unit, and sends differential data to mobile positioning terminals within the work area through a communication module. The differential data is preferably transmitted wirelessly, forming the uplink reference signal link in the system.

[0194] The mobile positioning terminal is installed on the vehicle body of the automatic line marking device. It simultaneously receives raw navigation signals from satellites and differential correction data from fixed base stations. Through its internal positioning calculation unit, it obtains current position, speed, and attitude information with centimeter-level accuracy and outputs the positioning results to the main control board module at certain intervals.

[0195] The mobile positioning module and the main control board module are connected via a serial bus to form a high-precision location information data link in the system.

[0196] As the core control unit of the system, the main control board module receives high-precision location information, time information and other data from the mobile positioning terminal on the one hand, and establishes a two-way data connection with the human-machine interaction module through the communication module on the other hand.

[0197] The handheld controller is used to send operation commands such as corner point acquisition instructions for the work area, cell division parameters, work mode selection, and start / stop to the main control board module. It also receives and displays the current work status, alarm information, and location information from the main control board module. The connection between the handheld controller and the main control board module uses wired serial communication to achieve bidirectional data flow for parameter transmission and status feedback.

[0198] At the execution control level, the main control board module outputs driving control commands, including target speed, steering angle, and start / stop control, to the traveling actuator control module based on the received high-precision position information, operating parameters, and path planning results. The traveling actuator control module includes a drive motor, steering actuator, and its drive circuit. After receiving the control signals output from the main control board, it completes the straight-line driving, steering, and U-turn actions of the unmanned lane marking device, and feeds back status signals such as vehicle speed, wheel speed, and steering position to the main control board to achieve closed-loop control.

[0199] Simultaneously, the main control board module also outputs control commands such as powder spreading start / stop signals and powder spreading motor speed settings to the powder spreading control and execution mechanism module to realize the opening, stopping, and powder spreading amount adjustment of the powder spreading mechanism 22. The powder spreading control and execution mechanism module drives the mixing motor, feeding mechanism, and other components to work according to the control commands from the main control board. When necessary, it feeds back information such as motor operating status and material level status to the main control board for monitoring and adjusting operational safety and powder spreading uniformity. The main control board module determines whether the predetermined start and end points have been reached based on the current position information. Within the corresponding section, it issues a powder spreading start command; when leaving the marked section, it issues a powder spreading stop command, thereby achieving synchronization between the travel trajectory and the powder spreading trajectory.

[0200] The power supply and safety protection module provides the necessary power to the main control board module, mobile positioning terminal, walking actuator control module, powder spreading actuator module, and handheld device, and forms a safety control link with the main control board through emergency stop switch 234, fuses, and protection circuits. When an emergency stop signal or serious fault is detected, the power supply and safety protection module can cut off the power to some or all actuators, the main control board will stop sending drive and powder spreading control commands, and the abnormal status will be indicated through the handheld device.

[0201] In some embodiments of the present invention, the main control board module is configured to run a state machine, which includes at least an idle mode, a manual mode, and an automatic mode. In automatic mode, the main control board module calls the navigation task list and automatically controls the walking actuator control module and the powder-spreading control module to work together.

[0202] As attached Figure 7 As shown, in some embodiments of the present invention, the automatic marking vehicle consists of a tracked walking assembly 1, a material feeding control power supply assembly 2, and a real-time positioning status assembly 3.

[0203] Among them, the tracked walking assembly 1 is the walking actuator of the automatic marking vehicle. It is powered by two control motors at the front and rear. The control motherboard sends control signals to drive the motors, so that the tracks can perform tasks such as forward movement, backward movement, and turning.

[0204] The real-time positioning status assembly 3 mainly consists of a mobile positioning terminal, an antenna, and a status indicator light 35. Specifically, the mobile positioning terminal is an RTK receiver, including a front receiver 31 and a rear receiver 32, and the antenna includes a front antenna 33 and a rear antenna 34.

[0205] The material feeding control power supply assembly 2 mainly consists of a power supply module 21, a powder spreading mechanism 22, a main control board, and a power safety management module 23. Among them, such as... Figure 8As shown, the main control board and power safety management module 23 includes: a motor driver 231, an air switch 232, a power management control board 233, an emergency stop switch 234, a power charging port 235, a rear protection board 236, and a main control box 237.

[0206] In some embodiments of the present invention, such as Figure 9 As shown, the powder-spreading mechanism 22 includes: a feeding funnel 221, a motor commutator 222, a powder-spreading drive motor 223, a drive shaft sleeve 224, a feeder cover plate 2213, a drive shaft 2214, a conical hopper 2212, a stirring rod seat 225, a stirring rod 2211, a stirring rod 226, a coupling 2210, a feeding screw 229, a connecting buckle 227, and a feeding cylinder 228.

[0207] The working principle of the powder-spreading mechanism 22 is as follows: Before spreading the powder, the marking powder / lime powder is spread along the line. Figure 9 The cone-shaped hopper 2212 is filled in the direction of the middle arrow. When the automatic marking device starts working, the powder-spreading drive motor 223 receives the control signal from the main control board and starts to rotate. After the powder-spreading drive motor 223 starts working, it drives the drive shaft 2214 to rotate through the motor commutator 222. The stirring rod seat 225 installed on the drive shaft 2214 is equipped with a stirring rod 2211. When the powder-spreading module is working, the stirring rod 2211 continuously stirs the marking powder in the cone-shaped hopper 2212, so that it is continuously sprinkled under the spiral action of the feeding screw 229 at the lower end of the stirring rod 226.

[0208] Finally, it should be noted that the various embodiments in this specification are described in a progressive manner, with each embodiment focusing on the differences from other embodiments. The same or similar parts between the various embodiments can be referred to each other.

[0209] The above embodiments are only used to illustrate the technical solutions of the present invention and not to limit them; although the present invention has been described in detail with reference to preferred embodiments, those skilled in the art should understand that modifications can still be made to the specific implementation of the present invention or equivalent substitutions can be made to some technical features without departing from the spirit of the technical solutions of the present invention, and all such modifications and substitutions should be covered within the scope of the technical solutions claimed in the present invention.

Claims

1. A method for automatic demarcation and navigation control of breeding experimental plots, characterized in that, Includes the following steps: S1: Collect the latitude and longitude coordinates of the four corner points of the breeding test area; establish a planar coordinate model of the test area based on the latitude and longitude coordinates of the four corner points; S2: Set the division parameters and line drawing mode for the test cells; divide the test cells based on the plane coordinate model and the division parameters, and generate cell grid lines; The grid lines of the test cell are used as the theoretical line-drawing path segments. The direction of each theoretical line-drawing path segment is determined according to a predetermined rule, and the theoretical line-drawing path segments are sorted. The line drawing mode is a back-and-forth serpentine mode. To ensure that the vehicle's direction of travel is consistent with the serpentine logic, the path is arranged in a back-and-forth serpentine manner during the sorting process. Odd-numbered rows are from left to right, and even-numbered rows are from right to left. The cross product sign between the diagonal vector of the test area and the first line drawing vector is judged. If the judgment result shows that the current path direction is opposite to the expected direction, the task list is reversed as a whole to make the path order consistent with the plot layout. S3: Generate a navigation task list for the automatic line marking vehicle based on the sorted theoretical line marking path segments, and navigate the automatic line marking vehicle according to the navigation task list so that it can drive automatically in the breeding test area, and control the powder spreading mechanism installed on the automatic line marking vehicle to spread powder and mark the line. S4: During the automatic driving process, the vehicle's current latitude and longitude information and the vehicle's current heading angle information are acquired in real time. Based on the vehicle's current latitude and longitude information and the vehicle's heading angle information, the lateral error and heading error between the vehicle's current position and the theoretical line segment it is currently traveling on are calculated. Based on the lateral error and the heading error, the Stanley tracking algorithm is used to generate steering control values ​​for the wheels of the automatic line-marking vehicle. Based on the steering control values, the speed of the left and right drive wheels of the automatic line-marking vehicle is adjusted so that the vehicle runs along the current theoretical line segment. Step S2 specifically includes the following steps: The long side direction and short side direction of the test area are determined based on the planar coordinates of the four corner points of the test area in the planar coordinate model. Based on the division parameters, equidistant interpolation is performed along the long side and the short side to generate cell grid lines; the cell grid lines are cell boundary lines or cell center lines. The grid lines of the test cell are used as the theoretical line-drawing path segments. The direction of each theoretical line-drawing path segment is determined according to a predetermined rule, and the theoretical line-drawing path segments are sorted. Based on the lateral offset distance between the nozzle of the powder spreading mechanism mounted on the automatic marking vehicle and the geometric center of the vehicle, offset compensation is performed on each theoretical marking path segment. In step S3, the method for providing route navigation for the automatically marked vehicle based on the navigation task list specifically includes: Each theoretical line segment after offset compensation is discretized into path points, and an ordered sequence of path points is generated. A task is generated for each path point in the ordered path point sequence to obtain a navigation task list; wherein, each path point's task includes the path point's task number, the path point's target coordinates, and the current task status; The automatic lane marking vehicle is controlled to sequentially execute the tasks of each path point in the navigation task list, so that the automatic lane marking vehicle automatically travels along each theoretical lane marking path segment in the test area.

2. The automatic line marking and navigation control method for breeding experimental plots according to claim 1, characterized in that, In step S1: The method for establishing the planar coordinate model of the test area includes the following steps: One corner point of the test area is selected as the origin corner point; The latitude and longitude coordinates of the test area are transformed into a Cartesian coordinate system with the origin corner point as the origin by using a predetermined plane coordinate approximation transformation formula; The predetermined planar coordinate approximation transformation formula is as follows: ； ； Where x is the abscissa of the Cartesian coordinate system, and y is the ordinate of the Cartesian coordinate system. The longitude of the origin corner point, The latitude of the origin corner point, The longitude of any point in the test area. Let latitude be any point in the test area. This is the scaling factor for converting latitude and longitude differences into meters.

3. The automatic line marking and navigation control method for breeding experimental plots according to claim 1, characterized in that, Step S4 specifically includes the following steps: During the task execution, the starting and ending coordinates of the theoretical line-marking path segment currently being traveled by the automatic line-marking vehicle, the vehicle's current latitude and longitude information, and the vehicle's current heading angle information are obtained in real time. The distance d between the vehicle's current position and the end point of the theoretically marked path segment is calculated based on the coordinates of the end point of the theoretically marked path segment and the vehicle's current latitude and longitude information. If the distance d is less than the predetermined distance threshold, the task index of the theoretical line drawing path segment currently being traveled by the vehicle is determined to be completed, and the task index of the next theoretical line drawing path segment is executed. Otherwise, based on the starting and ending coordinates of the currently traveled theoretical route segment and the theoretical heading angle of the currently traveled theoretical route segment, the following is determined: , Calculate the heading error between the vehicle's current heading and the target heading based on the vehicle's current heading angle information. ; If the heading error If the heading error exceeds a predetermined steering threshold, the automatically marking vehicle is controlled to turn in place until the heading error is corrected. The absolute value is less than the predetermined steering threshold; Otherwise, calculate the lateral error between the vehicle's current position and the theoretically marked path segment the vehicle is currently traveling on. And based on the lateral error With the heading error Calculate the overall error Then, the Stanley tracking algorithm is used to integrate the error. The signal is converted into a PWM signal for the wheel drive motor through linear mapping, forming the steering control quantity of the wheel, so that the vehicle can track and run along the sorted theoretically marked path segments.

4. The automatic line marking and navigation control method for breeding experimental plots according to claim 3, characterized in that, In step S4, the method for generating steering control values ​​for the wheels of the automatically lane-marking vehicle using the Stanley tracking algorithm specifically includes the following steps: Regarding the lateral error Nonlinear compression is performed, and the compression formula is: ； in, To account for the lateral error after nonlinear compression, The distance between the current projection point and the next path point. For lateral error gain; The lateral error after nonlinear compression and the heading error Amplitude limiting is applied, and the overall error is calculated. : ； in, and All are proportionality coefficients, and the comprehensive error is... The amplitude is limited to Within the range; The combined error The signals are converted into PWM differential signals for the left and right drive wheels of the automatically marked vehicle by linear mapping, thereby forming PWM signals for the wheel drive motors and steering control quantities for the wheels, enabling the vehicle to track and run along the sorted theoretical marked path segments.

5. The automatic line marking and navigation control method for breeding experimental plots according to claim 1, characterized in that, Further steps include: During automatic vehicle driving, when the automatically marked vehicle moves from the starting point of the previous theoretically marked path segment to the starting point of the next theoretically marked path segment, the target direction angle is calculated based on the vehicle's current coordinates and the starting coordinates of the next theoretically marked path segment. ; Control the vehicle to turn in place until the target steering angle is reached. With respect to the vehicle's current heading angle When the difference is less than the predetermined heading difference threshold, the vehicle body alignment is completed; After the vehicle body is aligned, the straight-line marking stage begins. A PID controller processes the heading error using proportional, integral, and derivative operations to calculate the steering correction. : ； in, For heading error, , , , These are the proportional, integral, and differential coefficients of the heading error, respectively. During vehicle driving, the basic forward PWM is denoted as The calculated PWM signals for the left and right wheels are as follows: ； ； in, This is the PWM signal for the left wheel. This is the PWM signal for the right wheel.

6. The automatic line marking and navigation control method for breeding experimental plots according to claim 1, characterized in that, Step S3 further includes the following steps: Configure the operating mode state machine of the automatic line marking vehicle; the operating mode includes at least idle mode, manual mode and automatic mode; in the idle mode, the drive motor and powder spreading mechanism of the automatic line marking vehicle are turned off; in the manual mode, the operation and powder spreading of the automatic line marking vehicle are controlled by manual commands; in the automatic mode, the navigation task list is called and executed to drive the vehicle and automatically control the powder spreading. The scheduled task processing function is set to read the current running mode at predetermined intervals and switch the state machine according to the interaction status between the user and the host computer based on manual commands.

7. An automatic demarcation and navigation control system for breeding experimental plots, used to execute the automatic demarcation and navigation control method for breeding experimental plots as described in any one of claims 1-6, characterized in that, include: Automatic lane marking vehicle, including a walking actuator and a powder spreading mechanism: The RTK positioning module, including a fixed base station and a mobile positioning terminal, is used to provide real-time positioning and orientation data for automated lane marking vehicles. The human-computer interaction module is used to collect the corner coordinates of the test area and the division parameters of the test sub-area input by the user, and to display the system status; The main control board module is communicatively connected to the RTK positioning module and the human-machine interaction module. It is used to perform test area modeling, automatic cell division, operation path planning and generate a navigation task list based on the corner coordinates and cell division parameters. It also performs path tracking calculation based on real-time positioning data and the navigation task list to generate driving control commands and powder spreading control commands. The walking actuator control module is connected to the main control board module and is used to receive the driving control command and drive the automatic line marking vehicle to move. The powder spreading control module, connected to the main control board module, is used to receive the powder spreading control command and control the mixing and feeding of the marking material in the powder spreading mechanism so as to spread powder on the ground synchronously during the movement of the automatic marking vehicle.

8. The automatic line marking and navigation control system for breeding experimental plots according to claim 7, characterized in that, The main control board module is configured to run a state machine, which includes at least an idle mode and an automatic mode. In the automatic mode, the main control board module calls the navigation task list and automatically controls the walking actuator control module and the powder spreading control module to work together.

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