Construction warehouse surface-based roller path planning method and system

Abstract

The application discloses a kind of based on construction warehouse surface compactor path planning method and system, belong to path planning technical field, the method includes S1, constructs axis alignment's bounding box;S2, the bounding box is rotated transformation, establishes rotation working coordinate system;S3, all trajectory points located in field area polygon boundary are as effective trajectory point set, and obtain basic trajectory;S4, for any the basic trajectory generates by several continuous offset segments Composed controllable offset curve, to obtain the actual operation trajectory of current iteration;S5, to all the actual operation trajectory according to the set operation iteration number repeated output, obtain actual operation trajectory point sequence;S6, the actual operation trajectory point is restored to original geographic coordinate system, outputs path data.The application is realized wheel trace space dislocation and uniform coverage by segmented controllable continuous offset curve and multi-iteration differentiation offset, improves overall compaction quality, and has high efficiency and reproducibility.

Description

Technical Field

[0001] This invention belongs to the field of path planning technology, specifically relating to a method and system for planning the path of a compaction vehicle based on the construction site. Background Technology

[0002] In site construction projects, such as water conservancy dam filling, road base compaction, airport runway compaction, and grain storage surface leveling, in order to ensure that the filling material reaches the design requirements for compaction or flatness, it is usually necessary to use mechanical equipment such as road rollers and leveling machines to repeatedly compact the rectangular or polygonal construction area in a predetermined direction.

[0003] The quality of compaction is influenced by a variety of factors, including compaction speed, number of passes, compacted thickness, vibration frequency, and amplitude. Generally speaking, as the compaction speed increases, the compaction effect tends to decrease; as the number of passes increases, the density increases accordingly. However, the quality of compacted material depends not only on the absolute degree of compaction, but also on the spatial uniformity of the compaction distribution.

[0004] Currently, conventional compactor path planning methods are mostly based on simple geometric parallel line generation strategies: existing technologies often repeatedly output the same set of basic trajectories multiple times, meaning that the actual driving paths of each operation completely overlap. For example... Figure 4 As shown, because the tracks of each pass completely overlap, the roller tracks repeatedly act on the same position, resulting in an excessive number of passes of compaction in the track zone and insufficient compaction in adjacent areas. This makes it impossible to adjust the compaction direction and coverage distribution according to the actual road conditions and compaction requirements.

[0005] To address this issue, some existing technologies attempt to apply a fixed offset to the entire strip, causing the trajectories of different passes to be shifted and staggered as a whole. However, this overall shift involves offsets between multiple strips, resulting in abrupt angle changes at both ends of the strip and disrupting the smooth transition between adjacent strips. More importantly, this method only focuses on the positional change of the entire strip and does not adjust the trajectory of individual strips, making it difficult to achieve a uniform distribution of compaction throughout the construction area, leading to poor overall compaction quality. Summary of the Invention

[0006] This invention provides a method and system for planning the path of a compaction vehicle based on the construction site, which solves the problem that existing compaction path planning cannot take into account the uniformity of coverage, resulting in uneven distribution of compaction degree and density throughout the entire area, thus affecting the overall compaction quality.

[0007] The objective of this invention can be achieved through the following technical solutions: A method for planning the path of a compaction vehicle based on the construction site includes the following steps: S1, Construct an axis-aligned bounding box based on the input field area polygon boundary vertex data; S2, Rotate the bounding box based on the preset working direction ⻆ to establish a rotating working coordinate system; S3, in the rotating working coordinate system, interpolate at equal intervals along two orthogonal directions to form a regular strip path structure; take all trajectory points located within the polygonal boundary of the field area as the set of effective trajectory points, and obtain the basic trajectory of each strip from the set of effective trajectory points; S4, Generate a controllable offset curve consisting of several continuous offset segments for any of the aforementioned basic trajectories to obtain the actual operation trajectory for the current pass; Each of the aforementioned continuous offset segments includes: an ascending segment with gradually increasing offset, a stable segment with constant offset, and a descending segment with offset gradually returning to the basic trajectory. S5, Repeat the output of all the actual operation trajectories according to the set number of operation passes to obtain the actual operation trajectory point sequence with the number of passes and the direction angle of travel; S6, rotate and transform the actual operation trajectory point sequence to restore it to the original geographic coordinate system; output path data including longitude, latitude, travel direction angle and the number of operation passes at the current point.

[0008] Preferably, the offset of the continuous offset segment in S4 is determined as follows: a random number generator is initialized with a fixed random seed, and the target offset is randomly generated within a preset range of maximum and minimum offset. Target offset:

[0009] The lengths of each stage are: , , ; The offset of the i-th point is: Ascending segment offset: ; Stable segment offset: ; Falling segment offset: ; The maximum offset is 1m, and the minimum offset is 0.5m; among which... This indicates a random number generation operation, where the random number ranges from 0 to 1 and can be any decimal. This is the maximum offset; Minimum offset; The target offset; The length of the rising segment; The length of the stable segment; This is the length of the descent segment.

[0010] Preferably, in S4, the continuous offset segment is applied along an offset direction perpendicular to the working direction, and the working direction vector is: ; The normal direction vector is: ; The final offset vector is: ; Randomly determine whether to deviate left or right along the direction of the operation; among which It is the offset vector; Let be the magnitude of the vector; The direction of the offset vector; It is the normal direction vector.

[0011] Preferably, in S5, the traversal method of alternating between forward and reverse order is used between two adjacent operation cycles; The direction of travel in S5 when switching actual work trajectories is calculated as follows: the direction of travel is calculated based on the positional relationship between the end point of the previous actual work trajectory and the starting point of the next actual work trajectory.

[0012] Preferably, the orthogonal direction in S3 is determined as follows: the first unit vector is along the working direction, and the second unit vector is along the normal direction perpendicular to the working direction. The first unit vector and the second unit vector are obtained by normalizing the bounding box edge vector after rotation.

[0013] Preferably, the method for constructing the bounding box aligned with the S1 centerline is as follows: extract the longitude and latitude values ​​of each vertex of the polygon boundary of the field area, and calculate the maximum and minimum values ​​respectively; The set of vertices of the polygon in the field area is ; The bounding box boundary is: Minimum longitude: ; Maximum longitude: ; Minimum latitude: ; Maximum latitude: ; in, , Let represent the longitude and latitude values ​​of the i-th vertex, respectively, and n be the total number of vertices; , These represent the minimum and maximum longitude values, respectively. , These represent the minimum and maximum latitude values, respectively.

[0014] Preferably, the rotation transformation in S2 is represented by quaternions, and the transformation matrix is ​​determined by the rotation axis and rotation degree fixed at the center of the earth, and the coordinate transformation is performed on the vertices of the bounding box in sequence.

[0015] Preferably, in S3, a ray casting algorithm is used to determine whether the trajectory point is located inside the original polygon area; the ray casting algorithm is specifically as follows: draw a ray from the trajectory point to be determined along the direction of increasing longitude, calculate the number of times the ray intersects with the boundary of the polygon area, if the number of intersection points is odd, the point is determined to be inside the polygon, and if the number is even, the point is determined to be outside.

[0016] A compaction vehicle path planning system based on the construction site surface includes: The bounding box construction module constructs axis-to-axis bounding boxes based on the vertex data of the field polygon boundary. The rotation transformation module performs rotation transformation on the bounding box of the axis pair according to the preset working direction; The basic trajectory generation module generates a basic trajectory in the rotating working coordinate system; The offset curve module generates a controllable continuous offset curve for each of the aforementioned basic trajectories; The path organization module is used to organize the paths of the continuous offset curves in an alternating forward and reverse order manner and calculate the operation direction of adjacent strips to obtain the actual operation trajectory point sequence; The data output module is used to perform a reverse rotation transformation on the actual operation trajectory point sequence and output path data.

[0017] Preferably, the offset curve module uses a fixed random seed to ensure the reproducibility of the offset results.

[0018] The beneficial effects of this invention are as follows: 1. This invention generates a consistent and uniformly spaced basic trajectory within any complex polygonal surface by interpolating a rotating bounding box and regular strips, eliminating the risk of missed compaction caused by boundary trimming. A trapezoidal wave continuous offset strategy ensures smooth transitions between passes, avoiding abrupt angle changes at both ends of the strip and guaranteeing stable energy transfer during roller turning. Simultaneously, alternating positive and negative offsets are configured for different passes, causing the wheel tracks to interlock spatially, effectively preventing repeated compaction or omissions at the same location and significantly improving the uniformity of coverage after multiple passes.

[0019] 2. This invention uses a fixed random seed, and the sequence of offset directions can be repeatedly generated under the same input. It retains the advantage of smooth transition of continuous offset segments, and enhances the uniformity of coverage through direction randomization, without adding extra turning complexity or reducing operation efficiency. Attached Figure Description

[0020] To facilitate understanding by those skilled in the art, the present invention will be further described below with reference to the accompanying drawings.

[0021] Figure 1The flowchart of the compaction vehicle path planning method based on the construction site surface provided by the present invention is shown.

[0022] Figure 2 This is a schematic diagram showing the relationship between the modules of the compaction vehicle path planning system based on the construction site surface provided by the present invention.

[0023] Figure 3 This is a schematic diagram of the number of rolling passes in this invention.

[0024] Figure 4 This is a graphical report illustrating the number of passes for rolling using existing technology. Detailed Implementation

[0025] To further illustrate the technical means and effects of the present invention in achieving its intended purpose, the following detailed description of the specific implementation methods, structures, features, and effects of the present invention, in conjunction with the accompanying drawings and preferred embodiments, is provided.

[0026] like Figures 1-3 As shown, a method for planning the path of a compaction vehicle based on the construction site includes the following steps: S1. Based on the input field area polygon boundary vertex data, extract the longitude and latitude values ​​of all vertices, and calculate the maximum and minimum values ​​respectively to determine the minimum axis-aligned bounding matrix that contains the field area polygon, i.e., the bounding box. S2, according to the construction process requirements, input a working direction ⻆, rotate the entire enclosure box and all points inside it around the center of the enclosure box to establish a rotating working coordinate system.

[0027] S3. In the rotating working coordinate system, interpolate at equal intervals along two orthogonal directions to form a regular strip path structure; take all trajectory points located within the polygon boundary of the field area as the set of effective trajectory points, and obtain the basic trajectory of each strip from the set of effective trajectory points. Based on the above steps, strip-type basic paths with consistent direction and uniform spacing can be generated in complex polygon areas.

[0028] S4 generates a controllable offset curve consisting of several continuous offset segments for any base trajectory to obtain the actual operation trajectory for the current pass; each continuous offset segment includes: an ascending segment with gradually increasing offset, a stable segment with constant offset, and a descending segment with offset gradually returning to the base trajectory. For example, if the maximum offset in the second pass is 0.25 meters, the length of the ascending segment is 4 meters, the length of the stable segment is 12 meters, and the length of the base trajectory is 100 meters, then the offset increases linearly from 0 to 0.25 meters within the range of 0 to 4 meters, remains at 0.25 meters within the range of 4 to 16 meters, decreases linearly to 0 within the range of 16 to 20 meters, and increases from 0 to 0.25 meters again within the range of 20 to 24 meters, and so on until the end of the trajectory.

[0029] The ascending and descending sections ensure a smooth transition of offset, completely avoiding the abrupt angle changes at both ends of the strip caused by the overall translation method, thus guaranteeing the continuity of the roller track and the stable change in the compacted material quality during roller turning; for example... Figures 3-4 As shown, by setting different maximum offsets for different number of passes, the wheel tracks of each pass can be staggered in space, avoiding repeated compaction or missed compaction of the same position. This fundamentally avoids the "strip-like" uneven compaction phenomenon caused by the complete overlap of tracks in traditional methods, and significantly improves the uniformity of coverage.

[0030] S5: Repeatedly output all actual operation trajectories according to the set number of operation passes to obtain a sequence of actual operation trajectory points with pass number markers and travel direction angles. Specifically, first, initialize an empty data sequence, and then, according to the total number of compaction passes N required by the construction process, perform the following operations in sequence for each pass from 1 to N: Call step S4, use the offset parameters corresponding to the pass, the maximum offset, the length of the rising segment, and the length of the stable segment, and pre-configure these parameters in the parameter table. For example, for the first pass, A=0 with no offset, for the second pass, A=+0.30 meters, for the third pass, A=-0.30 meters, for the fourth pass, A=+0.15 meters, etc., to generate the actual operation trajectory point sequence for the pth pass for each basic trajectory. For each trajectory, according to the travel direction of its respective strip, set the travel direction angle for each trajectory point, and append the coordinates, direction angle, and pass number marker of each trajectory point to the empty data sequence. After the loop ends, the data sequence contains complete information on all passes, all strips, and all discrete trajectory points. For example, when the total number of passes N=4, the following are generated sequentially: the first pass with no offset straight line trajectory, the second pass with a +0.30 meter trapezoidal wave offset, the third pass with a -0.30 meter trapezoidal wave offset, and the fourth pass with a +0.15 meter trapezoidal wave offset. The points on each trajectory are marked with the pass number and direction.

[0031] The above steps record the cumulative number of passes corresponding to each compaction position through pass marking, enabling construction managers to identify under-compacted and over-compacted areas, and thus guide additional compaction or parameter adjustment. Since the tracks of each pass are offset in the vertical direction to achieve spatial misalignment, the wheel tracks of adjacent passes interlock with each other, and the actual number of compaction passes at each point in the entire field tends to be consistent, thereby improving the spatial uniformity of compaction and density.

[0032] S6 rotates the actual operation trajectory point sequence to restore it to the original geographic coordinate system; it outputs path data including longitude, latitude, travel direction angle, and the current operation pass number. For example, a trajectory point in the rotated coordinate system is (x′=10.0, y′=-3.75). The original rotation angle α=30°. After inverse rotation, it has longitude 118.123° and latitude 39.256°. The travel direction angle of this trajectory point was originally 90°. After adding 30°, it becomes 120°, indicating that it should travel in the direction of 120° north of east in the geographic coordinate system; the pass number is marked as 2.

[0033] In summary, this embodiment generates a consistent and uniformly spaced basic trajectory within any complex polygonal surface by using a rotating bounding box and regular strip interpolation, eliminating the risk of missed compaction caused by boundary trimming. The use of a trapezoidal wave continuous offset strategy ensures smooth transitions between each pass, avoiding abrupt angle changes at both ends of the strip and ensuring stable energy transfer during roller turning. Simultaneously, different offsets with alternating positive and negative values ​​are configured for different passes, allowing wheel tracks to interlock spatially, effectively preventing repeated compaction or omissions at the same location and significantly improving the uniformity of coverage after multiple passes.

[0034] In one embodiment, the offset of continuous offset segments in S4 is determined as follows: a random number generator is initialized with a fixed random seed so that when the same input parameters (such as the basic trajectory and the offset segment length L) are run repeatedly, the generated random offset sequence is completely consistent. This ensures that the path planning results for the same pass and the same field area are repeatable and verifiable, facilitating path preview and on-site verification before construction. For each offset segment, a target offset is generated using a random number function within the preset maximum and minimum offset range.

[0035] Target offset:

[0036] in This indicates a random number selection operation. The random number range is any decimal between 0 and 1. In this embodiment, it is set to 1.0 meter and 0.5 meters respectively, meaning that the target offset of each offset segment will be randomly selected between 0.5 meters and 1.0 meter. The purpose of using random selection is to make the lateral misalignment amplitude between different offset segments have irregular differences, avoid the "secondary striping" effect that periodic offset may produce, further disperse the repetitive areas of the wheel tracks, and improve the uniformity of coverage.

[0037] Based on the total length L of the current offset segment, the length of each sub-segment is allocated according to the principle that the rising segment, the stable segment, and the falling segment are approximately of equal length. The specific calculation method is as follows: The length of the growth segment is rounded down to the nearest whole number. The length of the stable segment is rounded down. The length of the falling segment is taken as the remaining part; this ensures that the total length L is completely covered, and the lengths of the rising segment and the stable segment are equal (both are L / 3 rounded down). The falling segment may be slightly longer than the former two due to rounding, but the overall proportion is still close to three equal parts, so that the offset curve has an approximately trapezoidal symmetrical shape.

[0038] Next, for the i-th trajectory point within this offset segment, the actual offset offseti of the current point is calculated according to the sub-stage in which the point is located, using the following formula: Ascending segment offset: That is, the offset of the rising segment increases linearly with i, starting from 0; Stable segment offset: The offset remains constant at the target offset, forming the flat-top portion of the wave.

[0039] Falling segment offset: The offset decreases linearly from the target offset and eventually drops to 0.

[0040] The maximum offset is 1m, and the minimum offset is 0.5m; This is the maximum offset; Minimum offset; The target offset; The length of the rising segment; The length of the stable segment; This is the length of the descent segment.

[0041] Through the point-by-point calculations described above, an offset is assigned to each trajectory point within the current offset segment, and this offset is superimposed onto the coordinates of the base trajectory point to obtain the actual operational trajectory point. Subsequently, the next offset segment is processed, with each segment independently and randomly generating a new target offset and repeating the above segmentation and interpolation process until the end of the entire base trajectory. The final generated actual operational trajectory consists of multiple interconnected trapezoidal wave curves with randomized offsets and smooth segmentation.

[0042] The target offset of each offset segment varies randomly within the range of 0.5 to 1.0 meters, breaking the regular wheel track pattern that may be generated by fixed offset or periodic sine waves. This allows the rolling wheel tracks of different passes and different segments to form a more uniform staggered coverage in space, thereby more effectively reducing the problem of uneven compaction. On the other hand, the use of fixed random seeds ensures the repeatability and consistency of the path planning results, which facilitates the approval, storage and reproduction of construction plans, while avoiding unpredictable driving problems that may be caused by purely random paths.

[0043] In one embodiment, the continuous offset segments in S4 are applied with an offset direction perpendicular to the working direction, and the working direction vector is: In a rotating working coordinate system, it is usually along the positive or negative X′ axis, where v z The component is usually 0 in actual compaction.

[0044] The normal direction vector is: ; Introduce a random offset direction flag This is achieved by randomly generating a fixed random seed each time an offset segment is generated, where 1 represents the positive direction of the normal (e.g., the left side) and -1 represents the negative direction of the normal (the right side). Finally, based on... By combining the offset direction marker and the normal direction vector, the final offset vector is synthesized: The final offset vector has both magnitude and direction. Superimposing it onto the base trajectory point yields the spatial position of the actual operation trajectory point.

[0045] Randomly determine whether to deviate left or right along the direction of the operation; among which It is the offset vector; Let be the magnitude of the vector; The direction of the offset vector; It is the normal direction vector.

[0046] This embodiment achieves more flexible and uniform wheel track spatial misalignment: because the offset direction (left or right) of each offset segment is random, different segments may alternately deflect to the left or right, rather than always deflecting to the same side, thus further disrupting the wheel track repetition pattern and avoiding unilateral cumulative offset. Simultaneously, due to the use of a fixed random seed, the sequence of offset directions can be repeatedly generated under the same input, ensuring the determinism and traceability of the path planning results. It retains the advantage of smooth transitions in continuous offset segments, while enhancing coverage uniformity through direction randomization, without adding extra turning complexity or reducing operational efficiency.

[0047] In one embodiment, to achieve continuous reciprocating construction, each strip is repeatedly output according to a set number of passes. During the pass organization process, adjacent passes use an alternating forward and reverse traversal method, so that the construction equipment forms a reciprocating movement effect within the same strip. Specifically: for M passes of compaction tasks in the same row of strips, the k-th pass (k=0,1,...,M) 1) If k is even, the sampling points are traversed in ascending order; if k is odd, the sampling points are traversed in descending order. Through this alternation, the end of the strip can be naturally connected to the beginning of the next strip, realizing the continuous connection of the entire path and avoiding breakpoints or extra connection segments.

[0048] Secondly, after completing all M passes of compaction on the current strip, it is necessary to turn to the adjacent next strip. This requires calculating the travel direction angle of the actual working trajectory to guide the roller from the end point of the current strip to the start point of the next strip. In S5, the direction angle calculation method for switching actual working trajectories is as follows: the travel direction angle is calculated based on the positional relationship between the end point of the previous actual working trajectory and the start point of the next actual working trajectory. Specifically, let the end point of the previous strip be... The starting point of the second band is Then the direction α is calculated as follows: ; Because the travel direction angle is dynamically calculated based entirely on the geometric position of the actual trajectory points, rather than using a fixed preset value, it can adapt to the offset state of different strips, ensuring that the guidance control from the end of one strip to the beginning of another always points in the correct direction, avoiding sudden changes in direction or path misalignment. The travel direction angle calculation, combined with the alternating forward and reverse traversal strategy, enables a smooth and continuous transition at strip switching points, eliminating the need for additional connecting lines or manual specification of steering angles. This ensures the stability and safety of the automated road roller when following the path.

[0049] In one embodiment, after completing the rotational transformation in step S2, a bounding box in an axis-aligned rotating working coordinate system is obtained. The bounding box has two mutually perpendicular edge directions: the longer side is parallel to the working direction, and the shorter side is perpendicular to the compaction working direction. The orthogonal direction in S3 is determined as follows: the first unit vector is along the working direction. The normal direction perpendicular to the working direction is the second unit vector. First unit vector Second unit vector It is obtained by normalizing the edge vectors of the rotated bounding box.

[0050] The strip spacing (row spacing) is determined along the direction of the second unit vector, representing the interval between the starting lines of two adjacent strips; the sampling spacing (column spacing) is determined along the direction of the first unit vector, representing the interval between adjacent sampling points within the same strip. The specific calculation process is as follows: Let the two edge vectors of the rotated bounding box be and the long side direction vector be: And the short side direction vector: Then the first unit vector is The second unit vector is With the direction of the second unit vector as the row direction, the number of stripes is: With the direction of the first unit vector as the column direction, the number of sampling points in each strip is: Where row is the strip spacing and hang is the sampling column spacing.

[0051] In one embodiment, the method for constructing the axis-aligned bounding box in S1 is as follows: extract the longitude and latitude values ​​of each vertex of the field area polygon boundary, calculate the maximum and minimum values ​​respectively, and use these four extreme values ​​as the boundary to construct a rectangle. The four sides of the rectangle are parallel to the longitude and latitude lines respectively, forming a minimum axis-aligned bounding box that can completely contain the original field area polygon.

[0052] The set of vertices of the polygon in the field area is The maximum and minimum values ​​of the bounding box boundary vertices are as follows: Minimum longitude: Maximum longitude: Minimum latitude: Maximum latitude: ; in, , Let represent the longitude and latitude values ​​of the i-th vertex, respectively, and n be the total number of vertices; , These represent the minimum and maximum longitude values, respectively. , These represent the minimum and maximum latitude values, respectively.

[0053] For example, if the field area is the bottom surface of an approximately trapezoidal grain silo, with vertex coordinates of (118.10°, 9.20°), (118.25°, 39.20°), (118.20°, 39.35°), and (118.05°, 39.30°), then the calculated values ​​are: =118.05°, =118.25° =39.20° =39.35°, the bounding box is the rectangular region enclosed by these four extreme points. The bounding box does not change with the shape of the polygon and is always aligned with the latitude and longitude coordinate system, providing a unified and simple reference boundary for subsequent rotation transformations and strip division.

[0054] In one embodiment, the rotation transformation in S2 is represented by quaternions. The transformation matrix is ​​determined by a rotation axis and rotation angle fixed to the Earth's center. Coordinate transformations are then performed sequentially on the vertices of the bounding box. Specifically, based on a preset working direction angle, the bounding box of the axis-to-axis is rotated to establish a rotational working coordinate system. Let the rotation angle be θ (0 degrees for east and 90 degrees for north), and the rotation axis be the normal vector passing through the center point of the bounding box and perpendicular to the ground. Rotation transformations are represented using quaternions: .

[0055] For a bounding box vertex p, the rotated coordinates p′ are calculated as follows: First, convert the vertex from latitude and longitude coordinates to three-dimensional Cartesian coordinates (x, y, z) in a geocentric coordinate system; then, obtain the new Cartesian coordinates through quaternion rotation; finally, convert back to latitude and longitude coordinates. Let the rotation matrix be... ,but: The rotated bounding box has a uniform strip direction in the new coordinate system, ensuring that the path strips generated subsequently are consistent with the actual construction direction.

[0056] In one embodiment, step S3 uses a ray casting algorithm to determine whether a trajectory point is located inside the original polygonal region. Specifically, the ray casting algorithm involves drawing a ray from the trajectory point to be determined along the increasing longitude direction, calculating the number of intersections between the ray and the polygonal boundary of the field area, and determining whether the point is inside the polygon if the intersection count is odd, and outside if it is even. Specifically, let the point to be determined... The coordinates are Draw a ray from this point along the increasing longitude direction, and calculate the number of times this ray intersects the polygon boundary. Let the number of vertices of the polygon be... The vertex sequence is For each edge in When the following conditions are met: Calculate the longitude of the intersection point of the ray and the edge. ;like If the intersection point count is odd, the point is inside the polygon; if it is even, it is outside. Only points that meet the conditions are retained as the set of valid trajectory points, and each set of valid points constitutes the basic trajectory of a work strip. In this way, strip-shaped basic paths with consistent direction and uniform spacing can be generated within a complex polygonal region. Indicates latitude; Indicates longitude; , These represent the longitude and latitude values ​​of the i-th vertex, respectively, and i+1 represents the longitude or latitude value of the (i+1)-th point, which will not be elaborated further.

[0057] A compaction vehicle path planning system based on the construction site includes a bounding box construction module, a rotation transformation module, a basic trajectory generation module, an offset curve module, a path organization module, and a data output module.

[0058] The bounding box construction module receives the vertex data of the field polygon and outputs an axis-aligned bounding box to the rotation transformation module.

[0059] The rotation transformation module rotates the bounding box by combining the preset working direction angle, and outputs the rotated bounding box and transformation matrix to the basic trajectory generation module.

[0060] The basic trajectory generation module uses the rotation bounding box, strip spacing, and sampling spacing parameters to generate a basic trajectory point sequence and outputs it to the offset curve module.

[0061] The offset curve module applies segmented controllable offsets to the base trajectory based on the offset parameters of the current pass, generates the actual operation trajectory point sequence of the current pass, and outputs it to the path organization module.

[0062] The path organization module collects trajectory points from all passes, sorts them according to the alternating forward and reverse order rule, calculates the switching direction angle between strips, and outputs a complete trajectory sequence with pass number markers and direction angles to the data output module.

[0063] The data output module uses the inverse transformation matrix provided by the rotation transformation module to restore the coordinates and orientation angles of the trajectory points to the original geographic coordinate system, and finally outputs a path data file that can be used by navigation devices.

[0064] In one embodiment, the offset curve module uses a fixed random seed to ensure the reproducibility of the offset results. Specifically, during system initialization or the first call to the offset curve module, a fixed integer value is set as the seed for the random number generator (e.g., the seed value is set to 0). When the module needs to randomly generate the target offset and offset direction for each offset segment, it samples based on the random number generator initialized with the fixed seed. That is, when calling the random() function to obtain a random decimal in the range [0, 1), the same random value will be obtained each time the same offset segment is reached. In this way, even if the offset fluctuates randomly within a preset range (e.g., 0.5 to 1.0 meters) and the offset direction is randomly selected to deviate left or right, the overall generated offset curve still has determinism and reproducibility: the path planning results under the same field area, the same number of passes, and the same set of parameters will not change due to multiple calculations.

[0065] The above description is merely a preferred embodiment of the present invention and is not intended to limit the present invention in any way. Although the present invention has been disclosed above with reference to preferred embodiments, it is not intended to limit the present invention. Any person skilled in the art can make some modifications or alterations to the above-disclosed technical content to create equivalent embodiments without departing from the scope of the present invention. Any simple modifications, equivalent changes and alterations made to the above embodiments based on the technical essence of the present invention without departing from the scope of the present invention shall still fall within the scope of the present invention.

Claims

1. A method for planning the path of a compaction vehicle based on the construction site surface, characterized in that, Includes the following steps: S1, Construct an axis-aligned bounding box based on the input field area polygon boundary vertex data; S2, Rotate the bounding box based on the preset working direction angle to establish a rotating working coordinate system; S3, in the rotating working coordinate system, interpolate at equal intervals along two orthogonal directions to form a regular strip path structure; take all trajectory points located within the polygonal boundary of the field area as the set of effective trajectory points, and obtain the basic trajectory of each strip from the set of effective trajectory points; S4, Generate a controllable offset curve consisting of several continuous offset segments for any of the aforementioned basic trajectories, so as to obtain the actual operation trajectory for the current pass; Each continuous offset segment includes: an ascending segment with gradually increasing offset, a stable segment with constant offset, and a descending segment with offset gradually returning to the basic trajectory. S5, Repeat the output of all the actual operation trajectories according to the set number of operation passes to obtain the actual operation trajectory point sequence with the number of passes and the direction angle of travel; S6, rotate and transform the actual operation trajectory point sequence to restore it to the original geographic coordinate system; output path data including longitude, latitude, travel direction angle and the number of operation passes at the current point; The method for determining the offset of the continuous offset segment in S4 is as follows: a random number generator is initialized with a fixed random seed, and the target offset is randomly generated within the preset maximum and minimum offset range. Target offset: The lengths of each stage are: , , ; No. i The offset of each point is: Ascending segment offset: ; Stable segment offset: ; Falling segment offset: ； The maximum offset is 1m, and the minimum offset is 0.5m; among which... This indicates a random number generation operation, where the random number ranges from 0 to 1 and can be any decimal. This is the maximum offset; Minimum offset; The target offset; The length of the rising segment; The length of the stable segment; The length of the descent segment; The continuous offset segment described in S4 applies an offset direction perpendicular to the working direction, and the working direction vector is: ; The normal direction vector is: ; The final offset vector is: ; Randomly determine whether to deviate left or right along the work direction; among which, It is the offset vector; Let be the magnitude of the vector; The direction of the offset vector; It is the normal direction vector.

2. The method for planning the path of a compaction vehicle based on a construction site surface according to claim 1, characterized in that, In S5, the traversal method of alternating between forward and reverse order is used between two adjacent job passes; The method for calculating the travel direction angle when switching actual work trajectories in S5 is as follows: the travel direction angle is calculated based on the positional relationship between the end point of the previous actual work trajectory and the starting point of the next actual work trajectory.

3. The method for planning the path of a compaction vehicle based on a construction site surface according to claim 1, characterized in that, The orthogonal direction in S3 is determined as follows: the first unit vector is along the working direction, and the second unit vector is along the normal direction perpendicular to the working direction. The first unit vector and the second unit vector are obtained by normalizing the bounding box edge vector after rotation.

4. The method for planning the path of a compaction vehicle based on the construction site surface according to claim 1, characterized in that, The method for constructing the bounding box aligned with the S1 centerline is as follows: extract the longitude and latitude values ​​of each vertex of the polygon boundary of the field area, and calculate the maximum and minimum values ​​respectively; The set of vertices of the polygon in the field area is ; The bounding box boundary is: Minimum longitude: ; Maximum longitude: ; Minimum latitude: ; Maximum latitude: ; in, , Let represent the longitude and latitude values ​​of the i-th vertex, respectively, and n be the total number of vertices; , These represent the minimum and maximum longitude values, respectively. , These represent the minimum and maximum latitude values, respectively.

5. The method for planning the path of a compaction vehicle based on a construction site surface according to claim 1, characterized in that, The rotation transformation in S2 is represented by quaternions. The transformation matrix is ​​determined by the rotation axis and rotation angle fixed at the center of the earth, and the coordinate transformation is performed on the vertices of the bounding box in sequence.

6. The method for planning the path of a compaction vehicle based on a construction site surface according to claim 1, characterized in that, In S3, a ray casting algorithm is used to determine whether the trajectory point is located inside the original polygon area. The ray casting algorithm is as follows: draw a ray from the trajectory point to be determined along the direction of increasing longitude, calculate the number of times the ray intersects with the boundary of the polygon area, and if the number of intersection points is odd, the point is determined to be inside the polygon; if the number of intersection points is even, the point is determined to be outside the polygon.

7. A compactor path planning system based on a construction site surface, applicable to the compactor path planning method based on a construction site surface as described in any one of claims 1-6, characterized in that, include: The bounding box construction module constructs axis-aligned bounding boxes based on the vertex data of the field polygon boundary. The rotation transformation module performs rotation transformation on the axis-aligned bounding box according to a preset working direction angle; The basic trajectory generation module generates a basic trajectory in the rotating working coordinate system; The offset curve module generates a controllable continuous offset curve for each of the aforementioned basic trajectories; The path organization module is used to organize the path of the continuous offset curve in an alternating forward and reverse order manner and calculate the operation direction angle of adjacent strips to obtain the actual operation trajectory point sequence. The data output module is used to perform a reverse rotation transformation on the actual operation trajectory point sequence and output path data.

8. A compaction vehicle path planning system based on a construction site surface according to claim 7, characterized in that, The offset curve module uses a fixed random seed to ensure the reproducibility of the offset results.

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