A method and system for automatic path tracking of a track-type harvester

Abstract

The application discloses a caterpillar type harvester path automatic tracking method and system, and relates to the technical field of vehicle path tracking control; boundary object set is generated by obtaining operation boundary data, header boundary data, machine motion data and caterpillar execution data, and boundary chain is formed by filtering according to the direction connection, adjacent connection and header left and right end position change of the boundary object; the header passing area is demarcated along the boundary chain, the advancing zone is limited in combination with the relative relationship of the header, and the caterpillar control amount is generated according to the advancing zone, the machine motion data and the caterpillar execution data; after the execution of the caterpillar control amount, the next caterpillar control deviation is corrected by using the machine, the caterpillar and the header boundary feedback; when the boundary chain is interrupted or the connection is abnormal, the connection boundary is generated, and the boundary chain is connected back after the boundary object is obtained again. The path tracking object is kept corresponding to the actual harvesting boundary of the header, and the continuity of the path tracking control under the boundary abnormal scene is improved.

Description

Technical Field

[0001] This invention relates to the field of vehicle path tracking and control technology, and in particular to an automatic path tracking method and system for a tracked harvester. Background Technology

[0002] During field harvesting, tracked harvesters need to continuously move along crop rows, cut area boundaries, or uncut area boundaries using their tracked walking mechanism, ensuring the cutter head maintains a continuous connection with the boundaries of the crops to be harvested. Existing automatic path tracking methods typically use global navigation positioning (GNSS) paths, machine heading deviations, or visually recognizable boundaries as tracking targets, then convert the machine's deviation relative to these targets into track differential speed or steering control values. However, in actual harvesting scenarios, crop lodging, overlapping cut widths, missed cuts, stubble obstruction, mud and water reflections, and field boundary continuity can cause discontinuities, offsets, or multiple boundary mixing in the visible field, leading to visual errors. The perceived boundary, the preset path, and the actual boundary of the crop area entered by the header no longer stably correspond to the same operational benchmark. At the same time, when the tracked walking mechanism travels on muddy or straw-covered ground, it is prone to slippage, sinking, and steering lag, causing the changes in machine movement, track execution, and the positional changes of the left and right ends of the header relative to the crop boundary to be out of sync. In this case, even if the machine center can follow the navigation path or a certain visual boundary, the header may still deviate from the actual harvest boundary, resulting in incorrect boundary object selection, distortion of the header entry connection relationship, repeated correction of track control deviation, and misalignment when the boundary is interrupted or reappears.

[0003] How to unify the operation boundary, header position changes, machine movement and track execution status into a continuous operation benchmark, so that the path tracking object corresponds to the actual harvest boundary of the header, and maintain the correctability of track control deviation when the boundary is interrupted or the continuity is abnormal, is a current technical problem in this field. Summary of the Invention

[0004] To overcome the aforementioned deficiencies of the prior art, this invention provides an automatic path tracking method for tracked harvesters. In field harvesting operations, this method associates the work boundary with changes in the position of the header to form a boundary chain, and generates a travel belt and track control quantity based on the boundary chain. This allows the tracked harvester to update the path tracking control basis even when the boundary is interrupted or the connection is abnormal, reducing the risk of the header deviating from the actual harvest boundary.

[0005] To achieve the above objectives, the present invention provides the following technical solution: An automatic path tracking method for a tracked harvester, the tracked harvester comprising a body, a tracked walking mechanism, and a header, including: S1. Acquire work boundary data, cutter table boundary data, machine motion data and track execution data; identify boundary objects from work boundary data, match the cutter table boundary data with the boundary objects to obtain the positional changes of the left and right ends of the cutter table relative to the boundary objects, and associate the boundary objects and positional changes to generate a set of boundary objects. S2. Based on the extension direction and adjacent position relationship of the boundary objects in the boundary object set, establish the connection relationship between the boundary objects; then, based on the position change in the boundary object set, select the boundary objects that form a harvest connection with the cutting platform from the boundary objects with the connection relationship, and connect them according to the harvesting progress order to form a boundary chain. S3. Delineate the area through which the cutter passes along the boundary chain, compare the offset direction and offset change between the left and right ends of the cutter and the boundary chain, and obtain the relative relationship of the cutter; the travel zone is jointly defined by the area through which the cutter passes and the relative relationship of the cutter. S4. Compare the travel belt with the machine motion data and track execution data to obtain the track control deviation; generate the track control quantity from the track control deviation and output the track control quantity to the track travel mechanism; after the track travel mechanism executes the track control quantity, use the machine motion data, track execution data and cutter boundary data that are acquired again to correct the track control deviation and complete the feedback update of the track control deviation. S5. When a boundary object in the boundary chain is interrupted, disappears, or no longer forms a harvest connection with the header, a connection boundary is formed by combining the end direction of the boundary chain before the interruption, the area through which the header passes, and the direction of machine movement; the travel zone is updated using the connection boundary, and after a boundary object that forms a harvest connection with the header is re-obtained, the re-obtained boundary object is incorporated into the boundary chain.

[0006] The technical effects and advantages of this invention are as follows: The operation boundary, the position changes of the left and right ends of the header, the movement of the machine body and the execution status of the track are associated as a set of boundary objects, and further filtered to form a boundary chain. This transforms the path tracking object from a single identification edge into a continuous operation benchmark, thereby ensuring that the path control basis corresponds to the actual harvest boundary of the header and maintaining the correctability of control deviation when the boundary is interrupted or the continuity is abnormal. Directional continuity results, adjacent continuity results, and positional change continuity results are used together to screen boundary objects, so that boundary objects that only have appearance continuity but do not form a harvest continuity with the header are eliminated. This can reduce the probability of interfering boundaries such as lodging outlines, stubble shadows, and mud and water reflections entering the boundary chain, and enhance the correspondence between the boundary chain and the actual harvest process. The area through which the header passes is delineated along the boundary chain, and the travel zone is defined based on the offset direction and offset change of the left and right ends of the header relative to the boundary chain. This makes the controlled object of the tracked walking mechanism no longer stay on a single boundary line, but transform it into a spatial control area related to the header coverage area, which is conducive to making the tracked control results serve the maintenance of the header harvest boundary. The body deviation, track execution difference, and cutter deviation change are used together to correct the track control deviation in the next track control. The body response, track response, and cutter boundary state after the control quantity is executed can be reintroduced into the control calculation, making the deviation correction in muddy wet ground slippage or track steering lag scenarios more in line with the actual operation state. When the boundary chain is interrupted, disappears, or no longer forms a harvesting continuity with the header, the continuity boundary is generated by combining the direction of the end of the boundary chain before the interruption, the area through which the header passes, and the direction of machine movement. The re-acquired boundary object is then incorporated into the boundary chain through a reconnection determination, so that the travel zone can remain continuous when the boundary is temporarily unavailable, and returns to the real boundary tracking state after the boundary is restored. Attached Figure Description

[0007] Figure 1 This is a system block diagram of the present invention; Figure 2 This is a flowchart illustrating the generation of boundary object sets and boundary chains in this invention. Figure 3 This is a flowchart illustrating the process of generating the track, updating the track control feedback, and reconnecting the track in this invention. Detailed Implementation

[0008] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0009] Refer to the instruction manual for the whole process. Figure 1 An automatic path tracking method for a tracked harvester, wherein the tracked harvester includes a body, a tracked walking mechanism, and a header, and the specific method is as follows: S1, Generation of Boundary Object Sets This implementation process places the work boundary, the left and right ends of the cutter head, the machine's motion state, and the track execution state into the same work coordinate system, enabling direct comparison of the extension direction of the boundary objects, adjacent positional relationships, and the positional changes of the left and right ends of the cutter head relative to the boundary objects; refer to the appendix of the instruction manual for details. Figure 2 The implementation process includes the following steps: S1.1 Acquire work boundary data, header boundary data, machine motion data, and track execution data; wherein, the work boundary data includes continuous edge segments, the boundary sensing unit outputs at least one of the following data: work area image, distance point sequence, and edge contour, and the output results form edge segment data with a continuous endpoint sequence, which serves as continuous edge segments to characterize crop edges, cut area edges, or uncut area edges; the header boundary data includes the left end boundary position and the right end boundary position of the header, which are determined by the header structure dimensions, header installation position, and machine coordinates. The relationship is converted to represent the spatial position of the left and right ends of the cutter head at the current operation time; the machine motion data includes the current position of the machine, the direction of travel of the machine, and the change in the heading of the machine. The current position of the machine is used to represent the current position of the machine in the same machine coordinate system. The direction of travel of the machine is used to represent the forward direction of the tracked harvester in the current operation section. The change in the heading of the machine is used to represent the change in the heading of the machine relative to the previous data collection time or the previous operation position; the track execution data is used to represent the execution status of the track walking mechanism, including the execution status of the left track and the execution status of the right track, for subsequent track control deviation calculation and feedback update.

[0010] S1.2 When identifying boundary objects from the operation boundary data, continuous edge segments in the operation boundary data are marked as crop edge objects, harvested edge objects, or unharvested edge objects according to their position relative to the operation area in front of the header, the harvested area, and the unharvested area, thus obtaining boundary objects; where, the operation area in front of the header refers to the area located in front of the header along the machine's direction of travel and about to enter the header's coverage area; the harvested area refers to the area that the header has passed through and harvested; the unharvested area refers to the area that has not yet entered the header and still maintains the form of crops to be harvested; when performing marking, if the continuous edge segment is located in the area of ​​crops to be harvested, the boundary object is marked as follows: Between crops and non-crop areas, they are marked as crop edge objects; if a continuous edge segment is located between a harvested area and an unharvested area after the header has passed, it is marked as a harvested edge object, which is a boundary object obtained from the edge marking of the harvested area; if a continuous edge segment is located on the outer boundary of the unharvested area, or on the edge position formed by the gaps between crop rows within the unharvested area, it is marked as an unharvested edge object, which is a boundary object obtained from the edge marking of the unharvested area; boundary objects are used to represent the operational boundary units that can participate in the subsequent continuation relationship judgment, avoiding directly using the original edge segment as the path tracking object.

[0011] S1.3 When mapping the cutter platform boundary data to the boundary object, the left and right boundary positions of the cutter platform are transformed to the same machine coordinate system as the boundary object. The lateral position changes of the left and right boundary positions of the cutter platform relative to the boundary object are calculated respectively to obtain the position changes. The same machine coordinate system uses the machine's direction of travel as the longitudinal reference and the direction perpendicular to the machine's direction of travel as the lateral reference. The boundary object, the left boundary position of the cutter platform, and the right boundary position of the cutter platform are all transformed to this coordinate system. During the calculation, the boundary... The object's position in the lateral direction is used as a comparison benchmark. The lateral relative positions between the left and right edges of the cutter platform and the boundary object are read respectively. Then, the lateral relative positions at the current acquisition time are compared with the lateral relative positions at adjacent acquisition times or adjacent operation positions to obtain the lateral position changes of the left and right edges of the cutter platform relative to the boundary object. The position changes are used to characterize whether the left and right edges of the cutter platform are closer to, farther away from, continue in the same direction, or cross the boundary object.

[0012] S1.4 When generating a boundary object set by associating boundary objects and position changes, the boundary objects, position changes, aircraft travel direction, and aircraft heading changes are associated to generate a boundary object set. During execution, for each boundary object, its object type, spatial position, extension direction, and corresponding lateral position changes at the left and right ends of the cutter are recorded, and the aircraft travel direction and heading changes at the time the boundary object is generated are written into the same data entry. The boundary object set is composed of multiple data entries. Each boundary object in the boundary object set has spatial boundary attributes, relative change attributes at the cutter end, and aircraft motion attributes, which serve as inputs for S2 to establish continuity relationships and filter boundary objects that form harvest continuity with the cutter.

[0013] After implementing this process, the operation boundary data is organized into a set of boundary objects with regional attributes, changes in the left and right ends of the header, and references to machine movement. This set of boundary objects provides a unified data foundation for the subsequent generation of boundary chains, enabling subsequent operations to determine which boundary objects are not only visually continuous but also correspond to the actual harvesting process of the header under the same coordinates and the same operating direction.

[0014] S2, Boundary Chain Generation This implementation process forms a boundary chain based on the set of boundary objects. The boundary chain first confirms whether the boundary objects are continuous along the machine's direction of travel, then confirms whether adjacent boundary objects are spatially adjacent, and finally verifies whether the boundary object is indeed participating in the current harvesting process by utilizing the positional changes of the left and right ends of the header relative to the boundary object. By executing this implementation process, the boundary chain used in subsequent steps S3 corresponds to the actual harvesting boundary of the header. See the appendix of the instruction manual for details. Figure 2 The implementation process includes the following steps: S2.1. When establishing the continuity relationship between boundary objects based on the extension direction and adjacent position relationship of the boundary objects in the boundary object set, the direction of the body's movement is used as the direction reference. The direction relationship between the extension direction of each boundary object in the boundary object set and the direction reference is compared to obtain the direction continuity result that characterizes whether the boundary object extends along the direction of the body's movement. During execution, the spatial position and extension direction of each boundary object are first read from the boundary object set. The extension direction of the boundary object is obtained by the direction of the line connecting the front and rear endpoints of the boundary object. When the direction of the line connecting the front and rear endpoints cannot stably represent the main direction of the boundary object, it is obtained by the direction of the fitted line of the boundary object. When the boundary object forms a continuous trajectory in the continuous acquisition position, it is obtained by the main direction in the continuous acquisition position. Then, the extension direction is converted to the same body position described in S1. In the standard system, the machine's travel direction is taken as the longitudinal positive direction, and the extension direction of the boundary object is projected onto the machine's travel direction. When the projection is positive, and the boundary object does not mainly traverse the working area in front of the header laterally, the direction continuation result indicates that the boundary object extends along the machine's travel direction. When the projection is negative, or the boundary object mainly traverses the working area in front of the header laterally in the left-right direction, the direction continuation result indicates that the boundary object does not extend along the machine's travel direction. Here, a positive projection indicates that the boundary object has a component extending along the current harvesting travel direction, and traversing the working area in front of the header laterally indicates that the boundary object mainly appears as a lateral obstruction edge, a field edge, or a local miscellaneous edge. The direction continuation result serves as the input for subsequent adjacent continuation judgments, used to first exclude boundary objects that do not match the current working section's travel direction.

[0015] S2.2. Compare the directional continuity results to represent the end positions and adjacent positions between boundary objects extending along the machine's direction of travel, and obtain the adjacent continuity results representing whether the boundary objects are adjacent one after the other. During execution, only the boundary objects representing the directional continuity results extending along the machine's direction of travel are processed, and these boundary objects are sorted according to the machine's direction of travel. End positions refer to the front and rear positions formed by the boundary object along its extension direction, and adjacent positions refer to the front-to-back arrangement relationship of two boundary objects in the machine's direction of travel and their relative position relationship in the lateral direction. During comparison, if the latter boundary object is located in front of the former boundary object, and the rear position of the latter boundary object and the front position of the former boundary object can form a front-to-back continuity in the direction of travel, and their lateral positions are maintained, then the boundary object is considered adjacent. If two boundary objects are positioned on the same side of the cutter head's centerline or within a continuously connected area of ​​the cutter head's coverage, then the adjacent connection result indicates that the two boundary objects are adjacent one after the other. The connection is based on the rear end of the latter boundary object being located ahead of the front end of the former boundary object, and the two objects being projected in a continuous order in the longitudinal direction of the machine coordinate system. A continuously connected area of ​​the cutter head's coverage refers to the lateral positions of both objects falling within the working boundary area extending to the same side of the cutter head's lateral coverage. If two boundary objects overlap or are inverted in the direction of travel, laterally cross the cutter head's centerline, or are separated by another boundary object, then the adjacent connection result indicates that the two boundary objects are not adjacent one after the other. The adjacent connection result is used to indicate whether there is a spatial connection basis between boundary objects.

[0016] S2.3. Boundary objects that simultaneously possess both directional continuity results and adjacent continuity results are identified as boundary objects with continuity relationships. Specifically, a boundary object is included in the scope of boundary objects with continuity relationships only when the directional continuity result indicates that the boundary object extends along the direction of the machine's movement, and the adjacent continuity result indicates that the boundary object has a front-to-back adjacent relationship with the preceding and following boundary objects. Boundary objects with continuity relationships indicate that they have connection conditions in spatial direction and adjacent position, but this result only indicates spatial continuity and does not directly indicate that the boundary object necessarily belongs to the actual harvest boundary. It is necessary to continue to combine the positional changes obtained in S1 to make harvest continuity judgments.

[0017] S2.4. Using positional changes in the boundary object set as the basis for harvest continuity, when selecting boundary objects that form a harvest continuity with the cutter platform from the boundary objects with continuity relationships, compare the positional changes corresponding to the boundary objects with continuity relationships, and select the boundary objects whose positional changes of the left and right ends of the cutter platform relative to the boundary object remain in the same direction and do not cross each other between adjacent collection times or adjacent boundary objects. These are the boundary objects that form a harvest continuity with the cutter platform. Among them, the positional changes come from the lateral positional changes of the left and right boundary positions of the cutter platform relative to the boundary objects in S1. Continuity in the same direction means that between adjacent collection times or adjacent boundary objects, the lateral positional change direction of the left end of the cutter platform relative to the boundary object is not the same as the previous change direction. Conversely, the direction of change in the lateral position of the right end of the cutter relative to the boundary object is not opposite to the previous direction of change; no crossing occurs means that the lateral relative position of the left or right end of the cutter relative to the boundary object has not switched from one side of the boundary object to the other side, nor has the boundary object jumped from one side of the cutter's coverage area to the other side; the lateral relative position is distinguished by the lateral position of the boundary object, and the cutter end is marked as the first symbol when it is on one side and the second symbol when it is on the other side. If the symbol does not change between adjacent collection times or adjacent boundary objects, it indicates that no crossing has occurred; through this operation, boundary objects that are spatially connected but do not maintain a harvest corresponding to the actual entry of the cutter are excluded from the boundary chain formation process.

[0018] S2.4.1 When comparing the positional changes of boundary objects with a continuous relationship, the positional changes of the boundary objects with a continuous relationship are compared with the positional changes of adjacent boundary objects to obtain a continuous result representing whether the positional changes continue in the same direction and do not cross boundaries. During execution, two adjacent boundary objects with a continuous relationship are selected sequentially according to the harvesting progress order. The lateral positional changes of the left end of the cutter corresponding to the previous boundary object and the lateral positional changes of the left end of the cutter corresponding to the next boundary object are read, and the direction of change of the two is compared to see if they are consistent or continue. Similarly, the lateral positional changes of the right end of the cutter corresponding to the previous boundary object and the lateral positional changes of the right end of the cutter corresponding to the next boundary object are read. The lateral position change of the corresponding right end of the header is compared to see if the two changes are consistent or continuous. Then, the lateral relative position signs of the left and right ends of the header relative to the boundary objects are checked to see if they change between adjacent boundary objects. When the position change directions of both ends are not reversed and the lateral relative position signs do not change, the position change continuity result indicates that the position change continues in the same direction and does not cross any boundaries. When the position change direction of either end is reversed, or the lateral relative position sign of either end changes, the position change continuity result indicates that the position change does not continue in the same direction or crosses any boundaries. This position change continuity result is used to support the marking of subsequent non-harvested boundary objects.

[0019] S2.4.2 When a boundary object has directional continuity and adjacent continuity results, but the continuous result of positional change indicates that the positional change of the left and right ends of the header relative to the boundary object does not continue in the same direction or crosses over, the boundary object is marked as a non-harvested boundary object. A non-harvested boundary object refers to a boundary object that has a continuous appearance in the image, point series, or edge contour and can be continuous in direction and adjacent position, but cannot maintain the harvest corresponding to the positional change of the left and right ends of the header. In the lodged crop area, the appearance contour formed by the lodged crop extends along the direction of machine travel, and the edge of the stubble shadow is adjacent to the already cut boundary. When the positional change of the left and right ends of the header relative to the boundary object is reversed or crossed, the boundary object does not belong to the boundary that the current header actually harvests along. After marking the boundary object as a non-harvested boundary object, it will not be used as a component object of the boundary chain in the future.

[0020] S2.4.3. Remove non-harvest boundary objects from the boundary objects with continuity relationships, and use the remaining boundary objects as candidate boundary objects to select those that form harvest continuity with the header. Candidate boundary objects refer to boundary objects that have passed the direction continuity judgment and adjacent continuity judgment and have not been excluded by the position change continuity results. These candidate boundary objects are used in S2.4 to continue to select boundary objects that form harvest continuity with the header, so that the boundary chain formation process not only depends on the continuity of the boundary appearance, but is also constrained by the relative position change of the left and right ends of the header.

[0021] S2.5 Connect the boundary objects that form harvesting succession with the header according to the harvesting progress sequence to form a boundary chain; specifically, sort the boundary objects that form harvesting succession with the header according to the machine's travel direction, and determine the connection order between adjacent boundary objects according to the adjacent succession results, and organize the sorted boundary objects into a continuous boundary sequence; the boundary chain is a boundary sequence composed of boundary objects that form harvesting succession with the header, used to represent the harvesting boundary that can be used as a reference for automatic path tracking during the current operation; the boundary chain retains the direction succession results, adjacent succession results, position changes and position change continuity results of each boundary object, so that the subsequent S3 can delineate the area through which the header passes along the boundary chain, and generate the relative relationship of the header based on the offset direction and offset change of the left and right ends of the header and the boundary chain.

[0022] After this implementation process is executed, the boundary chain is derived from the joint screening of two types of constraints: spatial continuity and harvest continuity. The directional continuity results and adjacent continuity results are used to confirm whether the boundary object has a spatial basis for continuous operation boundary, and the position change continuity results are used to confirm whether the spatial boundary corresponds to the actual harvesting entrance of the header. In application: when the tracked harvester enters the lodged area, both the lodged contour edge and the real uncut boundary extend along the direction of the machine's movement, and both appear as continuous edges in the image. This implementation process continues to compare the position changes of the left and right ends of the header relative to these boundary objects. If the position change corresponding to the lodged contour edge crosses, while the position change corresponding to the real uncut boundary continues in the same direction, then the lodged contour edge is marked as a non-harvesting boundary object, and the real uncut boundary is preserved and connected to form a boundary chain, thereby establishing the subsequent travel zone on a boundary reference consistent with the actual harvesting process of the header.

[0023] S3, Movement Zone Generation This implementation process converts the boundary chain formed in S2 into a travel track that the tracked walking mechanism can execute. Based on the determined boundary chain, the coverage relationship and offset changes of the left and right ends of the header are introduced into the path control object. This allows S4 to calculate the track control deviation not only by referring to the machine's center position but also by controlling the header's state relative to the actual harvest boundary. See the appendix of the instruction manual for details. Figure 3 The implementation process includes the following steps: S3.1 When delineating the header passage area along the boundary chain, the boundary chain is used as the operational side boundary, and the lateral coverage range between the left and right ends of the header defines the header's coverage boundary relative to the boundary chain. The header passage area is then delineated along the boundary chain. The boundary chain is obtained by connecting the boundary objects that form a harvesting succession with the header in S2 according to the harvesting progress sequence, and is used to represent the operational side boundary that serves as the tracking reference in the current harvesting operation. The lateral coverage range between the left and right ends of the header is obtained by the lateral distance between the left and right end boundary positions of the header in the same machine coordinate system, and is used to represent the harvesting width that the header can cover in the lateral direction. During execution, the boundary chain position is read segment by segment along the extension direction of the boundary chain. The boundary chain is used as the operational side boundary on one side of the header, and then the coverage boundary is determined on the side of the boundary chain relative to the header according to the lateral coverage range between the left and right ends of the header. The header passage area is formed between the boundary chain and the coverage boundary. The header passage area is used to represent the spatial range that the header should cover when it travels along the boundary chain, and is the spatial basis for the subsequent generation of the travel zone.

[0024] S3.2. To obtain the relative relationship of the cutter table by comparing the offset direction and offset change between the left and right ends of the cutter table and the boundary chain, the positions of the left and right ends of the cutter table and the boundary chain are compared to obtain the offset direction and offset change of the left and right ends of the cutter table relative to the boundary chain. The relative relationship of the cutter table is then generated from the offset direction and offset change. The offset direction refers to the lateral deviation of the left or right boundary position of the cutter table relative to the boundary chain. The offset change refers to the trend of the lateral offset corresponding to this offset direction in adjacent acquisition times or adjacent working positions. During the comparison, the coordinates of the machine body are used... Within the system, using the lateral position of the boundary chain at the corresponding longitudinal position as a reference, the lateral relative positions between the left edge of the cutter and the boundary chain, and between the right edge of the cutter and the boundary chain are read respectively. The current lateral relative position is then compared with the lateral relative position at the previous acquisition time or the previous operation position to obtain the offset direction and offset change of the left and right edges of the cutter relative to the boundary chain. The relative relationship of the cutter is formed by the offset direction and offset change, which is used to characterize whether the cutter tends to move closer to the boundary chain, tends to move away from the boundary chain, maintains coverage, or has a tendency to deviate from the boundary chain.

[0025] S3.3 When the travel zone is jointly defined by the cutter platform's passage area and its relative relationship, the cutter platform's passage area is used as the spatial basis of the travel zone. The cutter platform's passage area is adjusted according to the reverse direction of the offset direction and the change in offset in the relative relationship of the cutter platforms to obtain the travel zone for the tracked walking mechanism to track. The travel zone is the spatial control area for the tracked walking mechanism to track. Its source is not a single geometric path line, but is jointly defined by the cutter platform's passage area and its relative relationship. During execution, if the relative relationship of the cutter platforms indicates that the left and right ends of the cutter platform deviate to one side relative to the boundary chain, the position of the travel zone is adjusted in the reverse direction of the offset within the cutter platform's passage area. When the offset change indicates that the degree of deviation increases, the travel zone moves in the opposite direction of the offset relative to the cutter platform's passage area. When the offset change indicates that the degree of deviation decreases, the travel zone remains within the current cutter platform's passage area. When the offset change indicates that the cutter platform crosses over, the travel zone is limited to the side that causes the cutter platform to exit the crossing state. The obtained travel zone is used in S4 to compare with the machine motion data and track execution data, and is used as the control object for calculating the track control deviation.

[0026] Through the above processing, the boundary chain is transformed from a boundary sequence into a spatial travel zone that can participate in track control, expanding the controlled object from a single boundary line to an area that the header can pass through and maintain harvest continuity. In application: when the boundary chain is located on the right side of the header's working boundary, and the right end of the header gradually deviates outward relative to the boundary chain, the relative relationship of the header indicates that the header has a tendency to move away from the boundary chain. The system adjusts the travel zone in the area through which the header passes according to the opposite direction of this offset, so that subsequent track control deviations can guide the track walking mechanism to drive the header back closer to the boundary chain.

[0027] S4, Track Control Deviation Feedback Update This implementation process converts the travel track into track control variables executed by the tracked walking mechanism. After the tracked walking mechanism executes these variables, it uses three types of feedback—body motion, track execution, and cutter boundary—to correct the track control deviation for the next iteration. The changes in the body, track, and cutter relative to the boundary chain after track execution are reintroduced into the control deviation, ensuring that track slippage, steering hysteresis, or cutter deviation from the boundary chain can be absorbed by the next control calculation. See the appendix of the instruction manual for details. Figure 3 The implementation process includes the following steps: S4.1 When comparing the track movement data with the machine body motion data and track execution data to obtain the track control deviation, the position and direction of the track movement data are compared with the machine body motion data to obtain the machine body deviation relative to the track. The track is obtained by S3 based on the cutter's passage area and its relative relationship, representing the spatial control area that the tracked walking mechanism needs to track. The machine body motion data includes the machine body's current position, direction of travel, and heading change. During the comparison, the machine body's current position, direction of travel, and heading change are converted to the same machine body coordinate system as the track. The lateral deviation direction and amount of the machine body's current position relative to the center area or boundary constraint area of ​​the track are read, and the directional deviation of the machine body's direction of travel relative to the extension direction of the track is read. The machine body deviation is composed of the lateral deviation direction, lateral deviation amount, and directional deviation, used to characterize whether the machine body is currently traveling along the track and how it deviates from the track. S4.2. Compare the left and right track execution states in the track execution data to obtain track execution differences. The left and right track execution states include at least one of the following: driving speed, driving torque, driving command execution state, and motion state fed back by the track transmission components. During the execution difference comparison, the left and right track execution states are read at the same acquisition time, and the differences between the two in driving speed, driving change direction, or driving intensity are compared to obtain track execution differences. Track execution differences are used to characterize whether the track travel mechanism is currently forming a left turn, right turn, straight travel, or insufficient differential speed execution state, providing a basis for subsequent judgment of the correspondence between track control quantities and machine motion results.

[0028] S4.3. The track control quantity is generated from the track control deviation. When the track control quantity is output to the track-walking mechanism, the machine body deviation is used as the path deviation term, and the track execution difference is used as the execution deviation term. These are combined to obtain the track control deviation. The track control deviation is then used to generate the track control quantity for adjusting the left and right tracks, and this quantity is output to the track-walking mechanism. The path deviation term characterizes the position and direction deviation of the machine body relative to the track, and the execution deviation term characterizes whether the current execution state of the left and right tracks can support the machine body to return to center on the track. During the merging process, the path deviation term is used as the target of the track control quantity. The correction basis is to use the execution deviation as the basis for the execution correction of the track control quantity to obtain the track control deviation; then, according to the correction direction indicated by the track control deviation, the left track speed correction quantity and the right track speed correction quantity are generated, and the track control quantity is formed by the left track speed correction quantity and the right track speed correction quantity, and then output to the track travel mechanism; for example, when the body deviation indicates that the body deviates to the left relative to the travel track, and the track execution difference indicates that there is no differential speed between the left track and the right track sufficient to make the body return to the right, the track control quantity is generated as the left and right track adjustment quantity to make the body return to the direction of the travel track.

[0029] S4.4 After the tracked traveling mechanism executes the track control quantity, when correcting the track control deviation using the re-acquired machine motion data, track execution data, and cutter boundary data, the machine motion data, track execution data, and cutter boundary data are acquired again. The re-acquired machine motion data is compared with the traveling belt to obtain the change in machine deviation; the re-acquired track execution data is compared with the track control quantity to obtain the change in track execution; and the re-acquired cutter boundary data is compared with the boundary chain to obtain the change in cutter deviation. The changes in machine deviation, track execution, and cutter deviation are used to correct the track control deviation for the next operation. The change in machine deviation is obtained by comparing the machine deviation before and after the execution of the track control quantity, and is used to characterize whether the machine is moving closer to the traveling belt. The track execution change is obtained by comparing the re-acquired track execution data with the output track control quantity, and is used to characterize whether the left and right tracks form corresponding execution according to the track control quantity; the header deviation change is obtained by comparing the re-acquired header boundary data with the boundary chain, and is used to characterize whether the left and right ends of the header are closer to the harvest boundary corresponding to the boundary chain after the track control quantity is executed; when correcting the track control deviation for the next time, the machine deviation change is used to adjust the path deviation item, the track execution change is used to adjust the execution deviation item, and the header deviation change is used to correct the correction direction related to the actual header boundary connection in the track control deviation, so that the next track control deviation is not only determined by the machine position, but also affected by the actual track execution state and the header boundary state.

[0030] S4.4.1 When correcting the next track control deviation using changes in body deviation, track execution, and cutter deviation, the track execution change is compared with the body deviation change to obtain the response correspondence result of the track execution change to the body deviation change. During execution, the differential speed direction or speed change direction of the left and right tracks represented by the track execution change is read, and then the body deviation change is read to indicate whether the body is moving closer to, away from, or maintaining deviation from the track. The direction of the track execution change is compared with the correction direction of the body deviation change. If the track execution change indicates that the track travel mechanism has performed differential or speed adjustment for return to center, and the body deviation change decreases synchronously, then the response correspondence result indicates that the track execution change corresponds to the body deviation change. If the track execution change has occurred, but the body deviation change has not decreased, or the correction direction of the body deviation change is opposite to the expected direction of the track execution change, then the response correspondence result indicates that the track execution change does not correspond to the body deviation change.

[0031] S4.4.2 When the direction of the track execution change represented by the response result is inconsistent with the correction direction of the body deviation change, or when the track execution change does not reduce the body deviation change, the response result is taken as the track execution response deviation, and the correction direction of the cutter's deviation relative to the boundary chain is determined by the cutter deviation change. The track execution response deviation indicates that the track travel mechanism has undergone an execution change, but this change has not been effectively converted into a correction change of the body relative to the travel track. This situation corresponds to slippage on wet ground, insufficient adhesion due to straw cover, or track steering lag. The correction direction of the cutter's deviation relative to the boundary chain is obtained from the cutter deviation change. If the cutter boundary data, after comparing with the boundary chain, indicates that the left and right ends of the cutter are far from the boundary chain, the correction direction points to the side that brings the cutter closer to the boundary chain. If the cutter boundary data, after comparing with the boundary chain, indicates that the left and right ends of the cutter are excessively close or have crossed over, the correction direction points to the side that removes the cutter from the crossing state. When the track execution response is distorted, the next correction direction is still determined by the actual change of the cutter relative to the boundary chain.

[0032] S4.4.3. The track execution response deviation and deviation correction direction are used to correct the next track control deviation, resulting in the corrected next track control deviation. During execution, when a track execution response deviation exists, the track execution change is not used as the basis for the correction of the body deviation when forming the next track control deviation, and the path deviation item corresponding to the body deviation change is retained or re-included. At the same time, the deviation correction direction indicated by the cutter deviation change is written into the next track control deviation, so that the correction direction of the next track control quantity is consistent with the deviation correction direction. When there is no track execution response deviation, the body deviation change, track execution change, and cutter deviation change are used together to correct the next track control deviation. The corrected next track control deviation obtained in this way is used to generate the track control quantity again and output to the track travel mechanism.

[0033] In this implementation, the track control process is transformed from a one-time deviation control to a feedback update process. The machine body deviation is used to represent the relative state between the machine body and the track, the track execution difference is used to represent the actual execution relationship between the left and right tracks, and the header deviation change is used to represent whether the header is still harvesting along the boundary link. In application: when the tracked harvester performs right turn return control in muddy and wet land, the left and right track execution data have shown that the right turn differential has been formed, but the machine body deviation change has not decreased, indicating that the track execution change has not been effectively converted into machine return. At this time, the system takes this situation as the track execution response deviation and further reads the header deviation change. If the right end of the header is still far away from the boundary link, the next track control deviation will continue to adjust the track control amount according to the deviation correction direction of the header approaching the boundary link, so that the control result is closer to the actual harvest boundary of the header.

[0034] S5. Boundary Generation and Boundary Chain Reconnection This implementation process handles situations where the boundary chain is interrupted, disappears, or no longer forms a harvesting continuity with the header during actual harvesting. It utilizes the end direction of the boundary chain before the interruption, the area traversed by the header, and the direction of machine movement to form a continuity boundary, ensuring that the travel belt maintains a continuity basis related to the harvesting operation even when the actual boundary is temporarily unavailable. Once the boundary object is re-obtained, the boundary chain is reconnected through three types of comparisons: directional continuity, adjacent continuity, and harvest continuity. For details, please refer to the appendix to the instruction manual. Figure 3 The implementation process includes the following steps: S5.1 When a boundary object in the boundary chain is interrupted, disappears, or no longer forms a harvesting continuity with the header, the end direction of the boundary chain before the interruption, the area traversed by the header, and the machine movement direction are read. An interruption of a boundary object means that adjacent boundary objects in the boundary chain no longer satisfy the direction continuity result or the adjacent continuity result. The disappearance of a boundary object means that the corresponding boundary object cannot be obtained in subsequent operation boundary data. No longer forming a harvesting continuity with the header means that although the boundary object is still identified, the positional changes of the left and right ends of the header relative to that boundary object do not continue in the same direction or involve crossing it. The end direction of the boundary chain before the interruption is obtained from the extension direction of the last boundary object in the boundary chain that satisfies the harvesting continuity, and is used to represent the continuation direction of the boundary chain before the interruption. The area traversed by the header is used to limit the spatial range that the header can cover near the boundary chain. The machine movement direction is obtained from the machine movement data and is used to represent the actual travel trend of the tracked harvester when the boundary anomaly occurs.

[0035] S5.2 When forming a successor boundary by combining the end direction of the boundary chain before the interruption, the area through which the header passes, and the direction of machine movement, the end direction of the boundary chain before the interruption is used as the directional constraint, the area through which the header passes as the spatial constraint, and the direction of machine movement as the travel constraint to generate the successor boundary. In specific execution, the initial extension direction of the successor boundary is first determined along the end direction of the boundary chain before the interruption, and then the initial extension direction is restricted to the area through which the header passes, so that the successor boundary does not deviate from the harvest coverage area already established by the header. Subsequently, the travel orientation of the successor boundary is corrected by the direction of machine movement, so that the successor boundary is consistent with the current actual travel trend of the tracked harvester. The successor boundary is used to represent the temporary working boundary when the boundary chain is temporarily interrupted, and is not used as a result of permanently replacing the real boundary object. The successor boundary is generated by combining directional constraints, spatial constraints, and travel constraints to avoid deviating from the actual area through which the header passes by simply extrapolating the direction of the last boundary object.

[0036] S5.3 When updating the travel zone using the continuation boundary, the continuation boundary is used as a temporary continuation segment of the boundary chain, and the travel zone is updated jointly by the continuation boundary and the uninterrupted boundary objects in the boundary chain. The temporary continuation segment refers to the temporary boundary segment used to maintain the continuity of the travel zone before the actual boundary objects have met the harvest continuation conditions again. During execution, the continuation boundary is connected to the uninterrupted boundary objects in the boundary chain to form a temporary boundary chain for the current control cycle. Then, according to the travel zone generation method in S3, the cutter passage area is redefined along the temporary boundary chain and the travel zone is adjusted. The temporary boundary chain is only used to update the travel zone in the current control cycle and does not replace the formal object sequence of the boundary chain. The updated travel zone continues to be used by S4 to calculate the track control deviation, so that the tracked walking mechanism can still travel along the spatial area related to the current harvest process during the boundary interruption.

[0037] S5.4 During the process of updating the travel zone using the continuation boundary, the system receives the re-acquired boundary object. The re-acquired boundary object refers to the boundary object that is re-identified in the subsequent operation boundary data and is located near the continuation direction of the continuation boundary or near the area through which the header passes. The re-acquired boundary object is an uncut edge object, a cut edge object, or a crop edge object that is re-identified from the subsequent operation boundary data. The system does not directly incorporate the boundary object into the boundary chain because the boundary object reappears. Instead, it continues to confirm the directional continuation, adjacent continuation, and harvest continuation relationship between the boundary object and the continuation boundary and header boundary data through the reconnection judgment result. After the reconnection conditions are met, the boundary object replaces the continuation boundary and participates in the generation of the subsequent travel zone.

[0038] S5.5. Compare the directional continuation results and adjacent continuation results of the newly obtained boundary object with the continuation boundary, and compare the harvest continuation results of the newly obtained boundary object with the cutter boundary data to obtain the reconnection judgment result. When performing the comparison, first compare the extension direction of the newly obtained boundary object with the extension direction of the continuation boundary to obtain the directional continuation result of whether the newly obtained boundary object can continue along the direction of the continuation boundary. Then compare the positional relationship between the end position, adjacent position and end of the continuation boundary of the newly obtained boundary object to obtain the adjacent continuation result of whether the newly obtained boundary object can be adjacent to the continuation boundary. Then read the left end boundary position and right end boundary position of the cutter in the cutter boundary data, calculate the positional change of the left and right ends of the cutter relative to the newly obtained boundary object, and determine whether the positional change continues in the same direction and does not cross, to obtain the comparison result of whether the newly obtained boundary object forms a harvest continuation with the cutter. The reconnection judgment result is composed of the directional continuation result, the adjacent continuation result and the harvest continuation comparison result, and is used to determine whether the newly obtained boundary object can be reconnected from the temporary continuation boundary to the real boundary chain.

[0039] S5.6 When the reconnection determination result indicates that the reacquired boundary object satisfies the directional continuity result, the adjacent continuity result, and the harvest continuity with the header, the reacquired boundary object is incorporated into the boundary chain, and the travel zone is redefined by the incorporated boundary chain; specifically, if the reacquired boundary object extends along the continuity boundary direction, is adjacent to the end of the continuity boundary or an uninterrupted boundary object in the boundary chain, and the positional changes of the left and right ends of the header relative to the reacquired boundary object are in the same direction and do not cross, then the reacquired boundary object is taken as the new edge of the boundary chain. Boundary objects; after integration, the continuation boundary is no longer the main limiting basis for the travel zone. The system redefines the area through which the header passes along the updated boundary chain, and redefines the travel zone according to the offset direction and offset change between the left and right ends of the header and the updated boundary chain. If the reconnection determination result does not meet the above conditions, the continuation boundary continues to be used as a temporary continuation segment to update the travel zone, and S5.4 to S5.6 continue to be executed in subsequent control cycles until the reconnection determination result indicates that the re-obtained boundary object meets the directional continuation result, the adjacent continuation result, and the harvest continuation with the header.

[0040] This implementation process ensures that the boundary chain maintains path tracking even during short-term interruptions, obstructions, lodging interference, or field connection scenarios. The continuation boundary ensures that the travel belt does not suddenly disappear when the boundary is temporarily unavailable, and the reconnection determination result ensures that the true boundary is not blindly merged into the boundary chain after it reappears. In application: when the tracked harvester enters a dust-covered area, the end boundary object in the boundary chain disappears. The system reads the end direction of the boundary chain before the interruption, the area traversed by the header, and the direction of machine movement to generate a continuation boundary, and uses the continuation boundary to continue updating the travel belt. When the dust weakens and the boundary object is regained, the system does not directly merge the boundary object into the boundary chain. Instead, it first determines whether it is connected to the continuation boundary in direction, adjacent in position, and whether it forms a harvesting connection with the header. Only when all three conditions are met is the re-acquired boundary object reconnected to the boundary chain, thus restoring the tracked harvester from a temporary connection state to a true boundary tracking state.

[0041] This invention also provides an automatic path tracking system for a tracked harvester. The tracked harvester includes a body, a tracked walking mechanism, and a header, as shown in the attached specification. Figure 3 The system includes a data acquisition module, a boundary chain generation module, a track generation module, a track control module, and a continuity update module; used to execute the above methods, specifically: The data acquisition module is used to acquire work boundary data, cutter table boundary data, machine motion data and track execution data, and generate a set of boundary objects, corresponding to the execution of S1; The boundary chain generation module is used to establish the connection relationship between boundary objects based on the boundary object set, filter the boundary objects that form a harvest connection with the header, and form a boundary chain, corresponding to the execution of S2; The travel zone generation module is used to delineate the area through which the cutter passes along the boundary chain, generate the relative relationships between the cutter platforms, and define the travel zone by the area through which the cutter platforms pass and the relative relationships between the cutter platforms, corresponding to the execution of S3; The track control module is used to compare the track movement data with the machine body motion data and track execution data to generate track control deviation and track control amount. After the track walking mechanism executes the track control amount, it uses the data acquired again to correct the track control deviation for the next time, corresponding to the execution of S4. The continuation update module is used to generate a continuation boundary and update the travel zone when a boundary object in the boundary chain is interrupted, disappears, or no longer forms a harvest continuation with the header. After obtaining a boundary object that meets the harvest continuation conditions again, it is merged into the boundary chain, and S5 is executed accordingly. Intermediate results are passed between modules in the following order: data acquisition module, boundary chain generation module, travel belt generation module, track control module, and continuous update module. The boundary object set serves as the input to the boundary chain generation module, the boundary chain serves as the input to the travel belt generation module and the continuous update module, and the travel belt serves as the input to the track control module. The boundary chain and travel belt generated or updated by the continuous update module are then used by the travel belt generation module and the track control module.

[0042] Working Principle: During operation, the tracked harvester first acquires data on the working boundary, header boundary, machine movement, and track execution. Visible continuous edge segments in the field are organized into boundary objects, and the positional changes of the left and right ends of the header relative to each boundary object are calculated. Subsequently, instead of directly using a visible edge as the tracking path, the system first determines whether each boundary object extends along the machine's direction of travel and whether they are adjacent. Then, combined with the positional changes of the left and right ends of the header, it determines whether the boundary object truly connects to the header harvesting process, thus filtering and connecting them to form a boundary chain. Based on this, the system delineates the header's passage area along the boundary chain, generates a travel belt based on the offset direction and changes of the left and right ends of the header relative to the boundary chain, and compares the travel belt with the machine movement and track execution status to generate track control parameters. After the tracked walking mechanism executes, the system continues to read feedback changes from the machine, tracks, and header boundaries to correct the track control deviation for the next operation, ensuring that the path tracking data is continuously updated according to the actual harvesting status.

[0043] In practical applications, such as when a tracked harvester enters lodged crops, dust-covered areas, or muddy fields, the front sensor may simultaneously identify multiple edges, including the actual uncut boundary, the lodged outline edge, and the stubble shadow edge. This solution compares the positional changes of these edges with the left and right ends of the header. If an edge appears continuous but the left and right ends of the header change in the opposite direction or cross it, it is excluded and not included in the boundary chain. If the actual boundary is temporarily obscured by dust, the system will generate a continuing boundary using the end direction of the previous boundary chain, the area the header passes through, and the direction of machine movement, and continue updating the travel belt. After the dust weakens, the boundary object is re-identified, and it is then determined whether it is continuous in direction with the continuing boundary, adjacent in position, and forms a harvesting continuity with the header. If these conditions are met, it is then incorporated into the boundary chain. This allows the harvester to continuously correct its travel path around the actual harvesting boundary of the header.

[0044] The above description is merely a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. A method for automatic path tracking of a tracked harvester, the tracked harvester comprising a body, a tracked walking mechanism, and a header, characterized in that, include: S1. Acquire work boundary data, cutter table boundary data, machine motion data and track execution data; identify boundary objects from work boundary data, match the cutter table boundary data with the boundary objects to obtain the positional changes of the left and right ends of the cutter table relative to the boundary objects, and associate the boundary objects and positional changes to generate a set of boundary objects. S2. Based on the extension direction and adjacent position relationship of the boundary objects in the boundary object set, establish the connection relationship between the boundary objects; then, based on the position change in the boundary object set, select the boundary objects that form a harvest connection with the cutting platform from the boundary objects with the connection relationship, and connect them according to the harvesting progress order to form a boundary chain. S3. Delineate the area through which the cutter passes along the boundary chain, compare the offset direction and offset change between the left and right ends of the cutter and the boundary chain, and obtain the relative relationship of the cutter; the travel zone is jointly defined by the area through which the cutter passes and the relative relationship of the cutter. S4. Compare the travel belt with the machine motion data and track execution data to obtain the track control deviation; generate the track control quantity from the track control deviation and output the track control quantity to the track travel mechanism; after the track travel mechanism executes the track control quantity, use the machine motion data, track execution data and cutter boundary data that are acquired again to correct the track control deviation and complete the feedback update of the track control deviation. S5. When a boundary object in the boundary chain is interrupted, disappears, or no longer forms a harvest connection with the header, a connection boundary is formed by combining the end direction of the boundary chain before the interruption, the area through which the header passes, and the direction of machine movement; the travel zone is updated using the connection boundary, and after a boundary object that forms a harvest connection with the header is re-obtained, the re-obtained boundary object is incorporated into the boundary chain. In S2: S2.1 Using the direction of the body's movement as the direction reference, compare the directional relationship between the extension direction of each boundary object in the boundary object set and the direction reference to obtain the directional continuity result characterizing whether the boundary object extends along the direction of the body's movement; S2.2 Compare the end positions and adjacent positions between boundary objects with directional continuation results to obtain the adjacent continuation results that characterize whether the boundary objects are adjacent one after the other. S2.

3. Define boundary objects that simultaneously have directional continuation results and adjacent continuation results as boundary objects with continuation relationships. S2.4 Compare the positional changes of boundary objects with a continuous relationship, and select the boundary objects whose positional changes of the left and right ends of the cutter relative to the boundary object remain in the same direction and do not cross each other at adjacent collection times or between adjacent boundary objects, to obtain the boundary objects that form a harvesting continuity with the cutter. S2.5 Connect the boundary objects that form a harvest succession with the header according to the harvesting progress sequence to form a boundary chain.

2. The method according to claim 1, characterized in that, In S1: S1.1 The operation boundary data includes continuous edge segments, the cutter platform boundary data includes the left end boundary position and the right end boundary position of the cutter platform, and the machine motion data includes the machine's direction of travel and changes in the machine's heading. S1.

2. Mark the continuous edge segments in the operation boundary data as crop edge objects, cut edge objects or uncut edge objects according to their position relative to the operation area, cut area and uncut area in front of the header, to obtain the boundary objects; S1.

3. Transform the left and right boundary positions of the cutting platform to the same body coordinate system as the boundary object, and calculate the lateral position changes of the left and right boundary positions of the cutting platform relative to the boundary object to obtain the position changes. S1.4 Associate the boundary objects, position changes, aircraft movement direction, and aircraft heading changes to generate a set of boundary objects.

3. The method according to claim 1, characterized in that, S2.4 also includes: S2.4.1 Compare the positional changes of boundary objects with successive relationships with the positional changes of adjacent boundary objects to obtain a continuous result of positional changes that characterize whether the positional changes continue in the same direction and do not cross boundaries. S2.4.2 When a boundary object has directional continuity results and adjacent continuity results, but the position change continuity results indicate that the position change of the left and right ends of the cutter relative to the boundary object does not continue in the same direction or crosses over, the boundary object is marked as a non-harvest boundary object. S2.4.

3. Remove non-harvest boundary objects from the boundary objects with succession relationships, and use the remaining boundary objects as candidate boundary objects to select those that form a harvest succession with the header.

4. The method according to claim 1, characterized in that, In S3: S3.

1. The boundary chain is used as the working side boundary, and the lateral coverage range between the left and right ends of the cutter table is used to define the coverage boundary of the cutter table relative to the boundary chain. The area through which the cutter table passes is defined along the boundary chain. S3.

2. Compare the positions of the left and right ends of the cutting platform with the boundary chain to obtain the offset direction and offset change of the left and right ends of the cutting platform relative to the boundary chain, and generate the relative relationship of the cutting platform from the offset direction and offset change. S3.

3. The area through which the cutter passes is used as the spatial basis of the travel belt. The area through which the cutter passes is adjusted according to the reverse direction and the change in offset in the relative relationship of the cutter to obtain the travel belt for the track walking mechanism to track.

5. The method according to claim 1, characterized in that, In S4: S4.1 Compare the position and direction of the running belt with the body motion data to obtain the body deviation relative to the running belt; S4.2 Compare the differences between the execution states of the left and right tracks in the track execution data to obtain the track execution differences; S4.

3. Take the body deviation as the path deviation item and the track execution difference as the execution deviation item, combine them to obtain the track control deviation, and generate the track control quantity for adjusting the left track and the right track from the track control deviation. S4.4 After the tracked walking mechanism executes the track control quantity, the machine motion data, track execution data, and cutter boundary data are acquired again. The acquired machine motion data is compared with the traveling belt to obtain the machine deviation change. The acquired track execution data is compared with the track control quantity to obtain the track execution change. The acquired cutter boundary data is compared with the boundary chain to obtain the cutter deviation change. The machine deviation change, track execution change, and cutter deviation change are used to correct the track control deviation for the next time.

6. The method according to claim 5, characterized in that, S4.4 includes: S4.4.1 Compare the changes in track actuation with the changes in body deviation to obtain the response results of track actuation changes to body deviation changes; S4.4.2 When the direction of the track execution change represented by the response result is inconsistent with the correction direction of the body deviation change, or when the track execution change does not reduce the body deviation change, the response result shall be taken as the track execution response deviation, and the deviation correction direction of the cutter relative to the boundary chain shall be determined by the cutter deviation change. S4.4.

3. Utilize the track execution response deviation to weaken the corrective effect of track execution changes on the next track control deviation, and enhance the corrective effect of cutter deviation changes on the next track control deviation according to the deviation correction direction, to obtain the corrected next track control deviation.

7. The method according to claim 1, characterized in that, In S5: S5.1 When the boundary object in the boundary chain is interrupted, disappears, or no longer forms a harvesting connection with the header, read the end direction of the boundary chain before the interruption, the area through which the header passes, and the direction of machine movement. S5.

2. Using the end direction of the boundary chain before the interruption as the directional constraint, the area through which the cutter passes as the spatial constraint, and the direction of the body's movement as the travel constraint, generate the continuation boundary. S5.

3. Treat the continuation boundary as a temporary continuation segment of the boundary chain, and update the travel zone together with the continuation boundary and the uninterrupted boundary objects in the boundary chain.

8. The method according to claim 7, characterized in that, The S5 also includes: S5.4 During the process of updating the travel strip while the continuation boundary is being used, receive the newly acquired boundary object; S5.

5. Compare the direction continuation results and adjacent continuation results of the newly obtained boundary object with the continuation boundary, and compare the harvest continuation of the newly obtained boundary object with the cutter boundary data to obtain the reconnection judgment result. S5.6 When the reconnection determination result indicates that the re-acquired boundary object satisfies the direction continuation result, the adjacent continuation result, and the harvest continuation with the header, the re-acquired boundary object is merged into the boundary chain, and the travel zone is redefined by the merged boundary chain.

9. An automatic path tracking system for a tracked harvester, the tracked harvester comprising a body, a tracked walking mechanism, and a header, characterized in that, For performing the method according to any one of claims 1-8, comprising: The data acquisition module acquires work boundary data, cutter table boundary data, machine motion data, and track execution data; it identifies boundary objects from the work boundary data, matches the cutter table boundary data with the boundary objects to obtain the positional changes of the left and right ends of the cutter table relative to the boundary objects, and associates the boundary objects with the positional changes to generate a set of boundary objects. The boundary chain generation module establishes the connection relationship between boundary objects based on the extension direction and adjacent position relationship of the boundary objects in the boundary object set; then, based on the position change in the boundary object set as the harvest connection basis, it selects the boundary objects that form a harvest connection with the cutter from the boundary objects with the connection relationship, and connects them according to the harvesting progress order to form a boundary chain. The travel zone generation module delineates the area through which the cutter passes along the boundary chain, compares the offset direction and offset change between the left and right ends of the cutter and the boundary chain, and obtains the relative relationship of the cutter; the travel zone is jointly defined by the area through which the cutter passes and the relative relationship of the cutter. The track control module compares the track movement data with the machine body motion data and track execution data to obtain the track control deviation; it generates the track control quantity from the track control deviation and outputs the track control quantity to the track travel mechanism; after the track travel mechanism executes the track control quantity, it uses the machine body motion data, track execution data and cutter platform boundary data acquired again to correct the track control deviation, thus completing the feedback update of the track control deviation; The continuity update module, when a boundary object in the boundary chain is interrupted, disappears, or no longer forms a harvest continuity with the header, combines the end direction of the boundary chain before the interruption, the area through which the header passes, and the direction of machine movement to form a continuity boundary; uses the continuity boundary to update the travel zone, and after regaining a boundary object that forms a harvest continuity with the header, merges the regained boundary object into the boundary chain.

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