Automatic steering system and harvester, automatic steering method, automatic steering program, recording medium

Abstract

An automatic steering system for a field work vehicle that travels from an entry start travel path (Ln) to an entry target travel path (Lm) via a turn by automatic travel, the automatic steering system including: an initial turn path calculation section that calculates an initial turn path (C1) for initial turn travel following travel along the entry start travel path (Ln); a later turn path calculation section that calculates a later turn path (C2) for later turn travel following travel along the initial turn path; an entry path calculation section that calculates an entry path (Lin) connecting the later turn path (C2) and the entry target travel path (Lm); and a turn radius (R) of the initial turn path (C1) is set larger than a turn radius of the later turn path (C2).

Description

Technical Field

[0001] This invention relates to an automatic steering system and harvester, an automatic steering method, an automatic steering program, and a recording medium. Background Technology

[0002] [1]

[0003] Previously, there were automatic steering systems used by field work vehicles that automatically drove from the starting point driving path to the target driving path by turning.

[0004] The automated guided vehicle (AGV) automatically steers along a linear path covering the work area. It repeats the process of entering the starting path, turning, and then entering the target path. The turning is used to change the vehicle's orientation when the direction of entry from the starting path differs from the direction of entry into the target path.

[0005] The combine harvester in Patent Document 1 operates in unworked areas by sequentially connecting multiple parallel travel paths using directional turning (U-turn travel). The path used for directional turning is an arc with the interval between adjacent travel paths as its diameter (see Patent Document 1). Figure 1 Furthermore, in cases where there is a driving path in between, and the driver enters the target driving path from the starting point driving path by turning, (refer to Patent Document 1) Figure 8 An arc with a diameter larger than the path spacing is used as the path for turning. Turning for changes in aircraft orientation all use a path represented by an arc.

[0006] In the combine harvester of Patent Document 2, the path used for turning to change the direction of the machine is a path consisting of two arcs with the same radius and a straight line connecting those arcs (see Patent Document 2). Figure 9 , Figure 12 , Figure 15 ).

[0007] [2]

[0008] Previously, there were harvesters that automatically traveled along a path set in the field while overlapping the ends of the harvest width.

[0009] Patent document 3 discloses a work vehicle that automatically travels on a driving path comprising multiple straight roads generated based on the size of the work site, the working width, and an overlap value (overlap setting width). When generating a driving path covering the work site with a working width including a predetermined overlap value, if an unworked area with a width smaller than the harvest width is generated, the predetermined overlap value is increased to generate a driving path that avoids leaving an unworked area with a width smaller than the working width at the end.

[0010] Existing technical documents

[0011] Patent documents

[0012] Patent Document 1: Japanese Patent Application Publication No. 2017-055673

[0013] Patent Document 2: Japanese Patent Application Publication No. 2018-068284

[0014] Patent Document 3: Japanese Patent Application Publication No. 2017-134527 Summary of the Invention

[0015] The technical problem that the invention aims to solve

[0016] [1] Background Technology [1] The technical problem corresponding to the following is as follows.

[0017] In field work vehicles such as combine harvesters, considering the relationship between the minimum turning radius and the working width, it is difficult to connect two adjacent parallel driving paths with a single arc path for turning. Therefore, turning is performed when there is more than one driving path between the starting driving path and the target driving path. In such turning, a turning path consisting of two arcs and a straight line connecting those arcs, as shown in Patent Document 2, is used. However, in turning using two arcs, in order to reduce the distance between the starting driving path and the target driving path, a turning path with a small radius arc is required, but turning along such a path can damage the ground. Therefore, a suitable automatic steering method is desired for turning using two arcs in a way that is as compact as possible and does not damage the ground.

[0018] [2] Background Technology [2] The technical problem corresponding to the following is as follows.

[0019] In the work vehicle of Patent Document 3, by adjusting the overlap value, it is possible to perform work in a non-work area using a travel path set within the non-work area. Since the overlap value in the travel path generation algorithm of this work vehicle is variable, the work vehicle can essentially perform work using travel paths of various work widths. However, since the difference in overlap value is not considered in the steering control during automatic driving, the same steering control is performed regardless of whether the travel path is generated with a smaller overlap value or a larger overlap value.

[0020] The purpose of this invention is to provide a harvester that, when automatically traveling along a path generated with different overlap values, takes into account the different overlap values ​​for control.

[0021] Means for solving technical problems

[0022] [1] The solutions to the technical problem [1] are as follows.

[0023] This invention relates to an automatic steering system for a field work vehicle. The field work vehicle automatically travels from an entry point driving path to a target driving path via a turning maneuver. The system comprises: an initial turning path calculation unit that calculates an initial turning path following the initial travel along the entry point driving path; a subsequent turning path calculation unit that calculates a subsequent turning path following the initial turning path; and an entry path calculation unit that calculates an entry path connecting the subsequent turning path to the target driving path. The turning radius of the initial turning path is set to be larger than the turning radius of the subsequent turning path.

[0024] Field work vehicles often damage farmland during turning maneuvers, particularly when transitioning from straight to turning. This invention aims to mitigate farmland damage during this transition by increasing the turning radius of the initial turning path. Specifically, the turning radius of the initial turning path is set to be larger than the turning radius of the subsequent turning path used when entering the target driving path. Conversely, the invention also aims to decrease the turning radius of the subsequent turning path, enabling more compact turning maneuvers with a smaller interval between the entry point and the target driving path. Again, the turning radius of the subsequent turning path is set to be larger than the turning radius of the initial turning path.

[0025] If the entry point travel path is directly connected to the initial turning path, the vehicle, consisting of wheels or tracks, may run over predetermined crops that will be processed while traveling along the target entry point travel path during the initial turn. To avoid this, the vehicle needs to travel along an extension of the entry point travel path until it completely leaves the entry point travel path. Therefore, in a preferred embodiment of the invention, a preliminary path extending along the extension direction of the entry point travel path is calculated at the starting end of the initial turning path to prevent the field work vehicle from running over crops while turning.

[0026] In a preferred embodiment of the invention, the later turning path is an arc, and the initial turning path calculation unit calculates the initial turning path as an arc of a circle tangent to the extension of the entry point driving path and the tangent of the later turning path. In this structure, representing the turning path with an arc has the following advantages: it not only simplifies the calculation of the turning path, but also makes the transition paths from the entry point driving path to the initial turning path and from the initial turning path to the later turning path smooth and continuous lines suitable for automatic steering. In this case, if the tangent of the later turning path is orthogonal to the entry target driving path, then the initial turning path and the later turning path become 90-degree arcs, which is therefore preferred. Note that it is also possible for the later turning path to directly connect with the initial turning path.

[0027] In another preferred embodiment of the invention, the later turning path is an arc. At the rear end of the initial turning path, a straight intermediate path connected to the later turning path is calculated. The initial turning path calculation unit calculates the initial turning path as an arc of a circle tangent to the extension of the entry point driving path and the intermediate path. In this structure, the turning path is also represented by an arc. The transitions from the entry point driving path to the initial turning path, from the initial turning path to the intermediate path, and from the intermediate path to the later turning path are performed tangentially to the arc, thus achieving a smoother transition. Since the initial turning path and the later turning path, which become the turning target, are formed by arcs, steering control can be achieved where the actual turning radius of the field work vehicle matches the intended turning radius.

[0028] [2] The solutions to the technical problem [2] are as follows.

[0029] The harvester of the present invention automatically travels along a travel path set in a field while overlapping the ends of the harvest width. The harvester includes: a harvest travel mode selection unit for selecting a harvest travel mode; an overlap value setting unit for setting an overlap value; a travel path calculation unit for calculating the travel path according to the harvest travel mode, covering the target area at a path interval determined based on the harvest width and the overlap value; a vehicle position calculation unit for calculating the vehicle position; a control command generation unit for generating control commands based on the deviation between the travel path and the vehicle position, and the overlap value; and an automatic travel control unit for performing steering control based on the control commands.

[0030] In the case of harvesters such as combine harvesters, the layout (driving mode), harvesting width, harvesting speed, and control parameters of the driving path during harvesting are determined based on factors such as the shape and size of the field, the type and condition of the harvested crop, the operating travel width of the harvesting device, and the intentions of the driver and farmers. Various driving methods under different driving modes, harvesting widths, harvesting speeds, and control parameters are collectively referred to here as harvesting driving modes. In the harvester of the above-described structure of this invention, if an overlap value is set in the driving path calculated based on the harvesting driving mode, control commands are generated based on this overlap value and the deviation between the driving path and the vehicle's position. Therefore, different steering controls can be executed for driving paths with different overlap values. As a result, harvesting operations can be performed using automated driving with more appropriate steering control.

[0031] In a preferred embodiment of the invention, the overlap value setting unit changes the overlap value according to the harvesting driving mode. In this configuration, an optimal overlap value can be set for the selected harvesting driving mode, and automatic driving can be performed with that overlap value.

[0032] In a preferred embodiment of the invention, the width of the deviation-insensitive zone that invalidates the deviation is changed in a manner that expands in accordance with the increase of the overlap value. If the overlap value increases, the likelihood of harvest residue areas (overlooked harvesting areas) due to instability in automatic driving control is reduced. Furthermore, if the width of the deviation-insensitive zone is increased, steering correction is not performed under minute deviations, resulting in insensitive control, but this avoids the problem of slight machine swaying caused by steering corrections due to minute deviations. In this structure, when the overlap value is large, expanding the width of the deviation-insensitive zone suppresses slight machine swaying.

[0033] As a harvester that harvests crops while moving through fields, the following modes are well-known: a reciprocating driving mode that connects multiple parallel driving paths via U-turns; and a vortex driving mode that travels in a spiral pattern towards the inner edge of the work area. In the reciprocating driving mode, U-turns are used to connect driving paths selected sequentially from a group of parallel driving paths. In the vortex driving mode, a turning motion called an alpha turn, accompanied by reversing, connects sequentially the driving paths parallel to the sides of the polygonal work area. At the end of this turning motion, if the deviation (offset) between the vehicle's position and the next target driving path is large, an area where harvesting cannot be performed will be created. To avoid this, the entry must be temporarily stopped, reversed, and the entry must be restarted. However, if the overlap value increases, the allowable range of deviation in the vehicle's position increases, thus mitigating the conditions for restarting the entry. Therefore, in a preferred embodiment of the present invention, an entry deviation calculation unit is provided, which calculates the entry deviation between the target driving path and the vehicle's position, the target driving path being the driving path to be entered by turning, and the control command includes an entry abort command to stop entering the target driving path if the entry deviation exceeds the prohibited deviation, the prohibited deviation changing according to the overlap value. Attached Figure Description

[0034] Figure 1 This is a diagram illustrating the first embodiment (hereinafter referred to as the diagram). Figure 11 (The same applies to the previous ones), is a side view of a full-feed combine harvester as an example of a field work vehicle.

[0035] Figure 2 This is an explanatory diagram showing a combine harvester traveling around the harvesting area.

[0036] Figure 3 This is an explanatory diagram illustrating a driving pattern that involves repeated reciprocating motions connected by U-shaped turns.

[0037] Figure 4 This is an explanatory diagram illustrating the basic principle of calculating a driving path consisting of a U-shaped turning path and a straight driving path.

[0038] Figure 5 This is an explanatory diagram showing the use of the Alpha Turn vortex driving mode.

[0039] Figure 6 This is an explanatory diagram illustrating the harvesting process of a combine harvester using both manual and automatic driving.

[0040] Figure 7This is an explanatory diagram showing the relationship between the starting point driving path, the initial turning path, the later turning path, the entry path, and the entry target driving path.

[0041] Figure 8 This is an explanatory diagram showing the relationship between the starting point driving path, the initial turning path, the intermediate path, the later turning path, the entry path, and the entry target driving path.

[0042] Figure 9 This is an explanatory diagram showing the relationship between the starting point driving path, the preliminary path, the initial turning path, the later turning path, the entry path, and the entry target driving path.

[0043] Figure 10 It is an explanatory diagram showing the relationship between the starting point driving path, the preparatory path, the initial turning path, the intermediate path, the later turning path, the entry path, and the entry target driving path.

[0044] Figure 11 This is a functional block diagram showing the structure of the control system of a combine harvester.

[0045] Figure 12 This is a diagram illustrating the second embodiment (hereinafter referred to as the diagram). Figure 23 (The same applies to the previous one), is a side view of a full-feed combine harvester as an example of a harvester.

[0046] Figure 13 This is an explanatory diagram showing a combine harvester traveling around the harvesting area.

[0047] Figure 14 This is an explanatory diagram illustrating a driving pattern that involves repeated reciprocating motions connected by U-shaped turns.

[0048] Figure 15 This is an explanatory diagram showing a driving pattern that moves in a vortex-like motion towards the center.

[0049] Figure 16 This is an explanatory diagram illustrating the calculation of the driving path using the reciprocating driving mode with back-and-forth travel.

[0050] Figure 17 This is an explanatory diagram illustrating the calculation of the driving path using the reciprocating driving mode of a normal U-turn.

[0051] Figure 18 This is an explanatory diagram illustrating the calculation of the driving path in vortex driving mode.

[0052] Figure 19 This is an explanatory diagram illustrating the harvesting process of a combine harvester using both manual and automatic driving.

[0053] Figure 20This is an explanatory diagram showing the relationship between harvest width, overlap value, and path spacing.

[0054] Figure 21 This is an explanatory diagram showing the relationship between the increase or decrease of the overlap value and the width of the deviation insensitive zone.

[0055] Figure 22 This is an explanatory diagram showing the relationship between the increase or decrease of the overlap value and the limit angle when entering driving.

[0056] Figure 23 This is a functional block diagram showing the structure of the control system of a combine harvester. Detailed Implementation

[0057] [First Implementation]

[0058] First, refer to Figures 1 to 11 The first embodiment will be described.

[0059] Next, as an example of a self-driving field vehicle employing the automatic steering system of the present invention, a full-feed combine harvester will be described. Note that in this specification, unless otherwise specified, "front" ( Figure 1 The direction of arrow F shown indicates the front (or rear) of the aircraft in the forward / backward direction (direction of travel). Figure 1 The direction of arrow B (as shown) indicates the rear of the aircraft in the forward / backward direction (direction of travel). Additionally, left / right or lateral directions refer to the transverse direction of the aircraft (width direction) orthogonal to the forward / backward direction. "Up" ( Figure 1 The direction of the arrow U shown) and "down" ( Figure 1 The direction of arrow D shown indicates the positional relationship of the body 10 in the vertical direction, showing the relationship of its height above the ground.

[0060] like Figure 1 As shown, the combine harvester includes a body 10, a tracked driving device 11, a driver's unit 12, a threshing device 13, a grain bin 14, a harvesting unit 15, a conveying device 16, a grain discharge device 18, and a vehicle position detection module 80.

[0061] The traveling mechanism 11 is located on the lower part of the machine body 10. The combine harvester is capable of self-movement via the traveling mechanism 11. The driver's unit 12, threshing unit 13, and grain bin 14 are located on the upper side of the traveling mechanism 11, forming the upper part of the machine body 10. The driver of the combine harvester and the supervisor monitoring the operation of the combine harvester can ride in the driver's unit 12. Note that the supervisor can also monitor the operation of the combine harvester from outside the machine.

[0062] The grain discharge device 18 is located above the grain bin 14. Additionally, the vehicle position detection module 80 is mounted on the upper surface of the driver's cab 12.

[0063] The harvesting section 15 is located at the front of the combine harvester. Furthermore, the conveying device 16 is located at the rear of the harvesting section 15. The harvesting section 15 also includes a cutting mechanism 15a and a drum 15b. The cutting mechanism 15a cuts the standing grain stalks of the field. The drum 15b, while rotating, rakes together the standing grain stalks of the crop to be harvested. Through this structure, the harvesting section 15 harvests the grain (a type of crop) from the field. Moreover, the combine harvester can operate by simultaneously harvesting the grain from the field via the harvesting section 15 and traveling via the travel device 11.

[0064] The harvested rice stalks cut by the cutting mechanism 15a are conveyed by the conveying device 16 to the threshing device 13. In the threshing device 13, the harvested rice stalks are threshed. The rice grains obtained by the threshing process are stored in the grain bin 14. The rice grains stored in the grain bin 14 are discharged out of the machine as needed by the grain discharge device 18.

[0065] Additionally, a universal terminal 4 is provided on the driver unit 12. In this embodiment, the universal terminal 4 is fixed to the driver unit 12. However, the present invention is not limited thereto; the universal terminal 4 may also be configured to be detachable from the driver unit 12, and the universal terminal 4 may also be taken outside the combine harvester.

[0066] like Figure 2 As shown, the combine harvester automatically travels along a pre-defined path in the field. This requires information about the harvester's position. The harvester position detection module 80 includes a satellite positioning unit 81 and an inertial navigation unit 82. The satellite positioning unit 81 receives GNSS (global navigation satellite system) signals (including GPS signals) as position information transmitted from an artificial satellite (GS), and outputs positioning data for calculating the harvester's position. The inertial navigation unit 82 is equipped with a gyroscope accelerometer and a magnetic azimuth sensor, and outputs a position vector representing the instantaneous direction of travel. The inertial navigation unit 82 supplements the harvester position calculation by the satellite positioning unit 81. The inertial navigation unit 82 can also be configured in a different location than the satellite positioning unit 81.

[0067] The sequence of harvesting operations in the field using this combine harvester is described below.

[0068] First, the driver / monitor operates the combine harvester manually, such as... Figure 2As shown, harvesting is carried out while circling the boundary line of the field in the outer perimeter. The area that becomes the harvested area (operated area) through the circling harvesting is designated as the outer perimeter area SA. Furthermore, the inner area remaining as unharvested land (unoperated land) inside the outer perimeter area SA is designated as the unoperated area CA, which is the area to be harvested in the future. In this embodiment, the circling harvesting is carried out in a quadrilateral shape in the unoperated area CA. Of course, triangular or pentagonal unoperated areas CA can also be used.

[0069] Additionally, to ensure a sufficiently wide outer perimeter area (SA), the operator drives the combine harvester 2-3 times. During this drive, with each revolution, the width of the outer perimeter area (SA) increases, expanding the harvester's working width. After these 2-3 revolutions, the width of the outer perimeter area (SA) is approximately 2-3 times the harvester's working width. Note that the revolutions are not limited to 2-3 revolutions; they can also be 1 revolution or more than 4 revolutions.

[0070] When the combine harvester is traveling in the unworked area CA, which is the target area for harvesting, the outer perimeter area SA is used as space for the combine harvester to change direction. In addition, the outer perimeter area SA is also used as space for movement when temporarily stopping the harvesting journey and moving to the grain discharge site, or when moving to the fuel supply site.

[0071] Notice, Figure 2 The transport vehicle CV shown is capable of collecting and transporting grains discharged from the grain discharge device 18 of the combine harvester. When discharging grains, the combine harvester uses the grain discharge device 18 to discharge grains onto the transport vehicle CV after moving to the vicinity of the transport vehicle CV.

[0072] If an inner map data representing the shape of the unharvested area CA is created, the planted rice stalks in the unharvested area CA are harvested using automatic driving and turning driving. Automatic driving involves traveling along a linear (straight or curved) path calculated based on the inner map data, while turning driving involves moving from one driving path (the starting point of the turn) to the next driving path (the target turn). The driving mode used for harvesting (harvesting) the unharvested area CA is shown below. Figure 3 The reciprocating travel mode is shown. In this reciprocating travel mode, the combine harvester travels by connecting two travel paths parallel to one side of the unworked area CA using a U-shaped turning travel path as a turning travel path.

[0073] The driving path (consisting of a U-turn path and a straight driving path) used for automatic driving in the non-operational CA area using the reciprocating driving mode is calculated based on the inner map data in the following manner. For example... Figure 4 As shown, according to the inner map data, the unworked area CA is defined as a quadrilateral formed by the first side S1, the second side S2, the third side S3, and the fourth side S4. The first side S1 is the longer side of the unworked area CA, and this first side S1 is selected as the reference side S1. A line parallel to the reference side S1 and passing through it at a distance of half the working width (cutting width) from the reference side S1 is calculated, and this line is used as the initial reference line L1. This initial reference line L1 corresponds to the initial travel path. Note that when harvesting by first dividing the unworked area CA in the middle, the initial reference line L1 is calculated as a line parallel to the reference side S1 and passing through it at a distance further away from the reference side S1 (half the working width + an integer multiple of the working width).

[0074] To ensure sufficient space for the combine harvester to make a 180-degree turn from the starting travel path to the target travel path, the working width is increased by several times (in) parallel to the initial baseline L1. Figure 4 The next baseline L2 is calculated by taking a 3-fold interval between the initial baseline L1 and the turning point. The next baseline L3 is calculated using the same method. Thus, considering the space required for turning, the baselines are calculated sequentially. These baselines L1, L2, L3… correspond to the driving paths used for straight-line driving (entering the starting driving path and entering the target driving path). Figure 4 In the process, the shape of the unworked area CA is a quadrilateral, but even if it is a triangle, pentagon or other polygon, as long as the reference side S1 is selected, the driving path can be calculated sequentially using the same method.

[0075] Note that, in addition to the driving modes, there is also a vortex driving mode. In vortex driving mode, as... Figure 5 As shown, the combine harvester travels in a vortex-like pattern towards the center, following a circular trajectory similar to the shape of the unworked area CA. At this point, for the turning required in each corner area, a turning maneuver known as an alpha turn is employed, utilizing straight-ahead, reverse-turn, and forward-turn maneuvers.

[0076] In actual field harvesting operations, such as Figure 6 As shown, it is not uncommon for a combination of reciprocating and vortex driving modes to exist. Figure 6In the example, if the combine harvester enters the field (#a), it manually steers to perform a circumferential harvesting motion, forming an outer perimeter area SA (#b) on the outermost edge of the field, which is the harvested area. If the outer perimeter area SA formed by this circumferential harvesting motion reaches a size where the combine harvester can perform an alpha turn, a vortex driving mode is set for the unharvested area CA, and vortex driving is performed (#c). During this vortex driving, at least straight-line travel can be automatically driven by automatic steering. The vortex driving continues until the unharvested area CA reaches a size where it can perform a turning motion (ordinary U-turn, reversing turn) in the reciprocating driving mode (#d). Next, for the unharvested area CA, a driving path is set to cover the unharvested area CA in the reciprocating driving mode (#e). By performing reciprocating driving along the set driving path, the harvesting operation of the field is completed (#f).

[0077] The turning path used when entering the target path Lm from the starting point driving path Ln is as follows: Figures 7 to 10 exemplified. exist Figures 7 to 10 In this diagram, the starting travel path is denoted by Ln, and the target travel path is denoted by Lm. The interval (path interval) between the starting travel path Ln and the target travel path Lm is denoted by D. A turning path has an initial turning path C1 following the initial turn along the starting travel path Ln, a later turning path C2 following the later turn along the initial turning path C1, and an entry path Lin connecting the later turning path C2 to the target travel path Lm. The entry path Lin can be an extension of the target travel path Lm. Figure 8 and Figure 10 In the example, a straight intermediate path Lmid connecting to the later turning path C2 is sandwiched at the rear end of the initial turning path C1. In the turning paths illustrated here, the intermediate path Lmid is a tangent to both the initial turning path C1 and the later turning path C2. The initial turning path C1 is a 90-degree arc. Figure 9 and Figure 10 In the example, a preliminary path Lad is sandwiched between the initial turning path C1 and the end of the entry-point travel path Ln. The preliminary path Lad can also be considered as an extension of the entry-point travel path Ln. Figures 7 to 10In the illustrated turning paths, it is important that the radius R of the arc forming the initial turning path C1 is set to be greater than the radius r of the arc forming the later turning path C2. Regarding the turning radius R of the initial turning path C1, a minimum and maximum value can be predetermined considering the radius r of the arc forming the later turning path C2. This minimum and maximum value are values ​​greater than r, and the turning radius R of the initial turning path C1 is selected within this range. Furthermore, it is also possible to pre-set that the available turning radius R is a value greater than r.

[0078] The entry path Lin is an extension of the target driving path Lm. The subsequent turning path C2 used for turning towards the target driving path Lm is an arc of radius r tangent to the entry path Lin. The radius r is predetermined based on the combine harvester's turning radius. When minimizing turning space is prioritized over damaging the field, the combine harvester's minimum turning radius is used; when minimizing field damage is prioritized over turning space, a standard turning radius larger than the minimum turning radius is used.

[0079] The length of the entry path Lin is calculated to ensure that the combine harvester, which is turning along the later turning path C2, can reliably capture the target travel path Lm, enter the target travel path Lm with high precision, and enter the harvesting travel without harvesting residue. The minimum necessary length of this entry path Lin can be calculated based on the combine harvester specifications (harvesting width, turning performance), field characteristics (susceptibility to slippage, unevenness), and available space for turning.

[0080] exist Figure 7 In the example, the initial turning path C1 directly connects to the later turning path C2 and the starting point travel path Ln. In other words, the initial turning path C1 is a 90-degree arc of a circle tangent to both the later turning path C2 and the starting point travel path Ln. In this case, a prerequisite is required. This prerequisite is that the path intervals are relatively short; and that even if the turning journey begins immediately after harvesting on the starting point travel path Ln, the turning-side travel device 11 will not crush the planted straw in the unharvested area.

[0081] If, after entering the harvesting route Ln, the vehicle immediately enters a turning route, the turning device 11 will crush the planted rice stalks in the unharvested area. Figure 9 , Figure 10 As shown, the preliminary path Lad is calculated between the starting point driving path Ln and the initial turning path C1. If the preliminary path Lad is calculated, the length of the preliminary path Lad is extended by the length of the entering path Lin.

[0082] Path spacing ratio Figure 7, Figure 9 In cases where the initial turning path C1 and the later turning path C2 are directly connected, the radius R of the initial turning path C1 becomes very large. Therefore, the starting end of the initial turning path C1 will penetrate deeply into the starting travel path Ln, and during this turning motion, the combine harvester's travel mechanism 11 will crush the planted rice stalks. To avoid this situation, such as... Figure 8 , Figure 10 As shown, a straight intermediate path Lmid connecting the initial turning path C1 to the later turning path C2 is calculated on the rear side of the initial turning path C1.

[0083] Thus, the turning path used when turning from the starting point path Ln to the target path Lm can be appropriately selected based on the path interval D, the combine harvester specifications (harvesting width, turning performance), field characteristics (susceptibility to slipping, unevenness), and available space for turning. Figures 7 to 10 (One of the four turning modes shown). If a turn is impossible even using these turning modes, select... Figure 5 The Alpha mode is shown in the image.

[0084] Figure 11 The control system of the combine harvester is shown. The control system of the combine harvester includes a control unit 5 consisting of multiple electronic control units (ECUs) connected via an onboard LAN, as well as various input / output devices that communicate with the control unit 5 via signals and data.

[0085] The control device 5 serves as an input / output interface, comprising an output processing unit 58 and an input processing unit 57. The output processing unit 58 is connected to various motion devices 70 via a device driver 65. The motion devices 70 include a travel-related device group 71 and a work-related device group 72. The travel-related device group 71 includes, for example, an engine, transmission, braking, and steering system. The work-related device group 72 includes a harvesting device (…). Figure 1 The control equipment in the harvesting section 15, threshing device 13, conveying device 16, grain discharge device 18, etc. shown.

[0086] The input processing unit 57 is connected to a driving status sensor group 63, an operation status sensor group 64, and a driving operation unit 90. The driving status sensor group 63 includes a vehicle speed sensor, an engine speed sensor, a parking brake detection sensor, a gear shift position detection sensor, and a steering position detection sensor. The operation status sensor group 64 includes sensors that detect the driving status and attitude of the harvesting device, as well as sensors that detect the state of the straw and grains.

[0087] The driving operation unit 90 is a general term for any operating component that is manually operated by the driver and whose operation signal is input to the control device 5. The driving operation unit 90 includes a main gear lever 91 (as a gearshift lever), a steering lever 92, a mode operation component constituting a mode switching switch 93, and an automatic driving operation component 94. The mode switching switch 93 has the function of sending commands to the control device 5 to switch between automatic and manual driving. The automatic driving operation component 94 requests automatic driving to be initiated through driver input.

[0088] Reporting device 62 is used to report warnings related to the operation status and driving status to the driver, etc., and includes a buzzer, light, etc. Note that the general terminal 4 also functions as a device to report the operation status, driving status, and various information to the driver, etc., by displaying them on the touch panel 40.

[0089] The control device 5 is also connected to the general terminal 4 via an in-vehicle LAN. The general terminal 4 is a tablet computer equipped with a touch panel 40. The general terminal 4 has an input / output control unit 41, a work driving management unit 42, a driving path calculation unit 43, and a turning path calculation unit 44. The input / output control unit 41 has the function of constructing a graphical interface using the touch panel 40, and the function of exchanging data via a remote computer, wireless line, or Internet.

[0090] The operation and driving management unit 42 includes a driving trajectory calculation unit 421, a work area determination unit 422, and a discharge position setting unit 423. The driving trajectory calculation unit 421 calculates the driving trajectory based on the vehicle's position given by the control device 5. The work area determination unit 422, as shown in the figure... Figure 2 As shown, based on the travel trajectory obtained by the combine harvester circling the outer perimeter area SA of the field several times during harvesting, the field is divided into an outer perimeter area SA and an unworked area CA. The boundary line between the outermost line of the outer perimeter area SA and the field ridge is calculated, and the unworked area CA where automatic travel will take place is calculated using the innermost line of the outer perimeter area SA. The discharge position setting unit 423 sets the discharge parking position of the combine harvester when the grain bin 14 is full and the grains in the grain bin 14 are discharged to the transport vehicle CV by the grain discharge device 18. The discharge parking position is set in the outer perimeter area SA formed on the outer side of the field by circling the field during harvesting, and is located outside the corners of the polygonal outer perimeter area SA.

[0091] The driving path calculation unit 43 calculates a driving path for automatic driving for the unoperated area CA determined by the work area determination unit 422. If the driver has entered that manual driving of the outer perimeter area SA has ended, the path calculation is performed automatically in the selected driving mode.

[0092] The travel path calculation unit 43 determines the interval (path spacing) between adjacent travel paths based on the harvesting width (operating width) and overlap value of the harvesting section 15. Furthermore, the travel path calculation unit 43 utilizes... Figure 4 The algorithm described calculates the travel path for going straight.

[0093] Turning path calculation unit 44 calculates the turning path of a U-shaped turn. Figure 5 The diagram shows the turning path of the Alpha turn. Specifically, in order to calculate using... Figures 7 to 10 The described turning path includes an initial turning path calculation unit 441, a later turning path calculation unit 442, an entry path calculation unit 443, a preliminary path calculation unit 444, and an intermediate path calculation unit 445.

[0094] The late-turn path calculation unit 442 calculates a 90-degree arc with a turning radius preset by input operation on the touch panel 40 for the combine harvester, and uses this as the late-turn path C2. At this time, the entry path calculation unit 443 uses the calculated late-turn path C2 to calculate the length of the entry path required for high-precision entry into the target travel path Lm. The initial-turn path calculation unit 441 calculates the initial-turn path C1 used for the initial turn following the entry starting point travel path Ln. At this time, a value larger than the radius of the late-turn path C2 is used as the radius of the initial-turn path C1. The radius of the initial-turn path C1 corresponding to the radius of the late-turn path C2 is preferably tabulated. Based on the calculated initial-turn path C1 and late-turn path C2, and the path interval between the entry starting point travel path Ln and the target travel path Lm, the intermediate path calculation unit 445 calculates the necessary length of the straight intermediate path Lmid. Furthermore, the preparatory path calculation unit 444 calculates the necessary length of the preparatory path Lad based on the current harvesting width of the combine harvester, the specifications of the travel device 11, and the radius of the initial turning path C1.

[0095] During the calculation of the turning path using the turning path calculation unit 44, if the necessary lengths of the intermediate path Lmid and the preliminary path Lad are zero, then the following is calculated: Figure 7 The turning path is shown. If the necessary length of only the prepared path Lad is zero, then the following is calculated: Figure 8 The turning path is shown. If only the necessary length of the intermediate path Lmid is zero, then the following is calculated: Figure 9 The turning path is shown. If the required lengths of the intermediate path Lmid and the preliminary path Lad are not zero, then the following is calculated: Figure 10 The turning path shown.

[0096] The control device 5 includes a vehicle position calculation unit 50, a manual driving control unit 51, an automatic driving control unit 52, a driving path setting unit 53, an operation control unit 54, and a reporting unit 59.

[0097] The vehicle position calculation unit 50 calculates the vehicle's position in map coordinates (or field coordinates) based on positioning data sequentially transmitted from the satellite positioning unit 81. The vehicle position calculation unit 50 can also calculate the vehicle's position using the position vector and travel distance from the inertial navigation unit 82. Furthermore, the vehicle position calculation unit 50 can combine signals from the satellite positioning unit 81 and the inertial navigation unit 82 to calculate the vehicle's position. Moreover, the vehicle position calculation unit 50 can also calculate the vehicle's position based on the past travel direction of the vehicle position calculation unit 10, i.e., the orientation of the vehicle body 10.

[0098] The reporting unit 59 generates report data based on instructions from various functional units of the control device 5 and assigns it to the reporting device 62. When the driving mode is switched to automatic driving mode using the mode switching switch 93, the control device 5 determines whether automatic driving is permitted based on preset automatic driving permission conditions. If the determination result is permitted, an automatic driving start command is assigned to the automatic driving control unit 52.

[0099] The manual driving control unit 51 and the automatic driving control unit 52 have engine control functions, steering control functions, vehicle speed control functions, etc., and provide driving control signals to the driving equipment group 71. The operation control unit 54 provides operation control signals to the operation equipment group 72 in order to control the operation of the harvesting device.

[0100] This combine harvester can operate in both automatic and manual modes. Automatic mode involves driving the harvester to perform harvesting operations automatically, while manual mode involves driving the harvester to perform harvesting operations manually. When automatic mode is set, the path setting unit 53 receives the driving path calculated by the path calculation unit 43 and the turning path calculated by the turning path calculation unit 44 from the universal terminal 4, and sets these paths as the target for automatic steering. The automatic driving control unit 52 generates steering control signals to eliminate azimuth and positional deviations between the driving path and turning path set by the path setting unit 53 and the vehicle position calculated by the vehicle position calculation unit 50. Furthermore, the automatic driving control unit 52 generates control signals related to speed changes based on a pre-set speed value.

[0101] When manual driving mode is selected, if a manual operation signal is sent to the manual driving control unit 51 based on the driver's operation, the manual driving control unit 51 generates a control signal to control the driving equipment group 71, thereby realizing manual driving. Note that even in manual driving, the driving path and turning path set by the driving path setting unit 53 can be used to guide the combine harvester to travel along the driving path and turning path.

[0102] [Other embodiments of the first embodiment]

[0103] (1) In the above embodiment, the turning path calculation unit 44 is configured to calculate the initial turning path C1, the later turning path C2, the intermediate path Lmid, and the preliminary path Lad if the starting point driving path Ln and the target driving path Lm are determined. Alternatively, the turning path calculation unit 44 may adopt the following structure: the calculation functions of the initial turning path C1, the later turning path C2, the intermediate path Lmid, and the preliminary path Lad are tabulated, and if the determined starting point driving path Ln and the target driving path Lm are input, the data of the initial turning path C1, the later turning path C2, the intermediate path Lmid, and the preliminary path Lad are exported.

[0104] (2) Figure 11 The functional units shown are distinguished primarily for illustrative purposes. In practice, each functional unit may be combined with other functional units, or it may be divided into multiple functional units. For example, the functional units built into the general terminal 4 may be partially or entirely assembled into the control device 5.

[0105] (3) In the above embodiment, the circumferential harvesting is carried out by manual driving, but after the second week, automatic driving may also be used locally, especially for straight-line driving.

[0106] (4) In the above embodiments, an automatic steering system for field work vehicles has been described. However, each functional unit in the above embodiments may also be configured as an automatic steering program. Furthermore, the processing performed by each functional unit in the above embodiments may also be configured as an automatic steering method.

[0107] (5) Alternatively, this automatic steering procedure can be recorded on a recording medium.

[0108] (6) In the above embodiments, the application to a full-feed type combine harvester is shown, but the present invention can also be used in a semi-feed type combine harvester. In addition, it can also be used in various harvesters such as corn harvesters, potato harvesters, carrot harvesters, and sugarcane harvesters.

[0109] [Second Implementation]

[0110] The following is for reference Figures 12-23 The second embodiment will be described.

[0111] Next, as an example of a harvester capable of both automatic and manual operation according to the present invention, a full-feed combine harvester will be described. Note that in this specification, unless otherwise specified, "front" ( Figure 12 The direction of arrow F shown indicates the front (or rear) of the aircraft in the forward / backward direction (direction of travel). Figure 12 The direction of arrow B (as shown) indicates the rear of the aircraft in the forward / backward direction (direction of travel). Additionally, left / right or lateral directions refer to the transverse direction of the aircraft (width direction) orthogonal to the forward / backward direction. "Up" ( Figure 12 (The direction of arrow U shown) and "down" ( Figure 12 The direction of arrow D shown indicates the positional relationship of the body 210 in the vertical direction, showing the relationship of its height above the ground.

[0112] like Figure 13 As shown, the combine harvester includes a body 210, a tracked driving device 211, a driver's unit 212, a threshing device 213, a grain bin 214, a harvesting unit 215, a conveying device 216, a grain discharge device 218, and a vehicle position detection module 280.

[0113] A traveling mechanism 211 is mounted on the lower part of the machine body 210. The combine harvester is capable of self-movement via the traveling mechanism 211. A driver's unit 212, a threshing unit 213, and a grain bin 214 are mounted on the upper side of the traveling mechanism 211, forming the upper part of the machine body 210. The driver of the combine harvester and the supervisor monitoring the operation of the combine harvester can ride in the driver's unit 212. Note that the supervisor can also monitor the operation of the combine harvester from outside the machine.

[0114] The grain discharge device 218 is located on the upper side of the grain bin 214. In addition, the vehicle position detection module 280 is installed on the upper surface of the driver's seat 212.

[0115] The harvesting section 215 is located at the front of the combine harvester. Furthermore, the conveying device 216 is located at the rear of the harvesting section 215. The harvesting section 215 also includes a cutting mechanism 215a and a drum 215b. The cutting mechanism 215a cuts the standing grain stalks of the field. The drum 215b, while rotating, rakes together the standing grain stalks of the crop to be harvested. Through this structure, the harvesting section 215 harvests the grain (a type of crop) from the field. Moreover, the combine harvester can operate by simultaneously harvesting the grain from the field via the harvesting section 215 and traveling via the travel device 211.

[0116] The cut rice stalks, chopped by the cutting mechanism 215a, are conveyed by the conveying device 216 to the threshing device 213. In the threshing device 213, the cut rice stalks are threshed. The threshed grains are stored in the grain bin 214. The grains stored in the grain bin 214 are discharged from the machine as needed by the grain discharge device 218.

[0117] Additionally, a universal terminal 204 is provided on the driver unit 212. In this embodiment, the universal terminal 204 is fixed to the driver unit 212. However, the present invention is not limited thereto; the universal terminal 204 may also be configured to be detachable from the driver unit 212, and the universal terminal 204 may also be taken outside the combine harvester.

[0118] like Figure 13 As shown, the combine harvester automatically travels along a pre-defined path in the field. This requires information about the harvester's position. The harvester position detection module 280 includes a satellite positioning unit 281 and an inertial navigation unit 282. The satellite positioning unit 281 receives GNSS (global navigation satellite system) signals (including GPS signals) as position information transmitted from an artificial satellite (GS), and outputs positioning data for calculating the harvester's position. The inertial navigation unit 282 is equipped with a gyroscope accelerometer and a magnetic orientation sensor, and outputs a position vector representing the instantaneous direction of travel. The inertial navigation unit 282 supplements the harvester position calculation by the satellite positioning unit 281. The inertial navigation unit 282 can also be configured in a different location than the satellite positioning unit 281.

[0119] The sequence of harvesting operations in the field using this combine harvester is described below.

[0120] First, the driver / monitor operates the combine harvester manually, such as... Figure 13 As shown, harvesting is carried out while circling the boundary line of the field in the outer perimeter. The area that becomes the harvested area (operated area) through the circling harvesting is designated as the outer perimeter area SA. Furthermore, the inner area remaining as unharvested land (unoperated land) inside the outer perimeter area SA is designated as the unoperated area CA, which is set as the area to be harvested in the future. In this embodiment, the circling harvesting is carried out in a quadrilateral shape for the unoperated area CA. Of course, unoperated areas CA that are triangular, pentagonal, or other polygonal shapes can also be used.

[0121] Additionally, to ensure a sufficiently wide outer perimeter area (SA), the operator drives the combine harvester 2-3 times. During this drive, with each revolution, the width of the outer perimeter area (SA) increases, expanding the harvester's working width. After these 2-3 revolutions, the width of the outer perimeter area (SA) is approximately 2-3 times the harvester's working width. Note that the revolutions are not limited to 2-3 revolutions; they can also be 1 revolution or more than 4 revolutions.

[0122] When the combine harvester is traveling in the unworked area CA, which is the target area for harvesting, the outer perimeter area SA is used as space for the combine harvester to change direction. In addition, the outer perimeter area SA is also used as space for movement when temporarily stopping the harvesting journey and moving to the grain discharge site, or when moving to the fuel supply site.

[0123] Notice, Figure 13 The transport vehicle CV shown is capable of collecting and transporting the grains discharged from the grain discharge device 218 by the combine harvester. When discharging grains, the combine harvester discharges the grains to the transport vehicle CV using the grain discharge device 218 after moving to the vicinity of the transport vehicle CV.

[0124] If an inner map representing the shape of the unharvested area CA is created, the planted rice stalks in the unharvested area CA are harvested using a harvesting process consisting of autonomous driving and turn-to-transfer driving. Autonomous driving involves traveling along a linear (straight or curved) harvesting path calculated based on the inner map data. Turn-to-transfer driving is used to move from one harvesting path to the next. Note that the path used for turn-to-transfer driving is called the turn-to-transfer path. The driving mode used in the harvesting process is a reciprocating driving mode, which connects multiple parallel harvesting paths using U-turns. Figure 14 As shown); vortex driving mode, which is a mode of driving in a vortex shape along the outer edge of the unworked area CA (as shown); Figure 15 (As shown).

[0125] exist Figure 14 In the reciprocating travel mode shown, the combine harvester travels by connecting a path parallel to one side of the unworked area CA using U-shaped turns. U-shaped turns include regular U-turns that cross more than one travel path and turnaround turns that connect adjacent travel paths. A regular U-turn consists of two forward 90-degree turns and a straight 180-degree turn, although the straight turn may be omitted. A turnaround turn uses a forward 90-degree turn, a reverse turn, and a forward 90-degree turn, forming a 180-degree directional change.

[0126] exist Figure 15In the vortex driving mode shown, the combine harvester travels in a vortex-like pattern towards the center, connecting the working driving path (CA) with a similar shape to the unworked area using turning paths. Alpha turns, which combine straight-ahead, reverse-turn, and forward-turn maneuvers, are used at the corners of each circle. Note that the mode can be switched from vortex driving mode to reciprocating driving mode, or vice versa, during operation.

[0127] The driving path used for autonomous driving in the non-operational CA area using the reciprocating driving mode is calculated based on the interior map data in the following manner. For example... Figure 16 as well as Figure 17 As shown, according to the inner map data, the unworked area CA is defined as a quadrilateral formed by the first side S1, the second side S2, the third side S3, and the fourth side S4. The first side S1 is the longer side of the unworked area CA, and this first side S1 is selected as the reference side S1. A line parallel to the reference side S1 and passing through it at an inner position half the working width (cutting width) away from the reference side S1 is calculated, and this line is used as the initial reference line L1. This initial reference line L1 corresponds to the initial travel path. Note that when harvesting by first dividing the unworked area CA in the middle, the initial reference line L1 is calculated as a line parallel to the reference side S1 and passing through it at a distance further away from the reference side S1 (half the working width + an integer multiple of the working width).

[0128] When using a U-turn with minimal space required for a 180-degree turn (U-turn) as a turning transfer method, such as Figure 16 As shown, baselines L2, L3, ... are calculated at intervals of the working width, parallel to the initial baseline L1, and sequentially connected to the initial baseline L1 via a U-shaped turn. These baselines L1, L2, L3, ... correspond to the working travel path used for straight-line travel.

[0129] When using a regular U-turn that requires more space than a turnaround turn for turning and transfer driving, the work width is several times greater than the initial baseline L1. Figure 6 The interval is calculated as 3 times the initial baseline L1, and the next baseline L2 is connected via a U-shaped turn. Figure 17 As shown, the next baseline L3 is calculated using the same method. Thus, considering the space required for a typical U-turn, the baselines are calculated sequentially. These baselines L1, L2, L3… correspond to the working travel path used for straight-line driving.

[0130] In addition, Figure 16 as well as Figure 17 In the process, the shape of the unworked area CA is a quadrilateral, but even if it is a triangle, pentagon or other polygon, as long as the reference side S1 is selected, the driving path can be calculated sequentially using the same method.

[0131] With the vortex driving mode selected, the operational driving path for autonomous driving is calculated based on the inner map data as follows: (e.g., ...) Figure 18 As shown, the first side S1, which is the long side (or short side in vortex driving mode) of the unworked area CA, is selected as the reference side S1. A line parallel to the reference side S1 and passing through it at a position half the working width (cutting width) away from the reference side S1 is calculated, and this line is taken as the reference line L1. This reference line L1 is the initial reference line for the initial working travel path of the automatic driving. Furthermore, a line parallel to the second side S2 adjacent to the reference side S1 and passing through it at a position half the working width (cutting width) away from the second side S2 in the direction of travel of the combine harvester is calculated as the next reference line L2, which becomes the next working travel path that is the target of the subsequent automatic driving of the initial working travel path. The initial working travel path and the next working travel path are connected by an alpha turn (special turn), which realizes the machine body turning at the angle formed by the reference side S1 and the second side S2. Similarly, the next reference line L3 is calculated sequentially. These baselines L1, L2, L3... correspond to the working travel path used for straight-line driving.

[0132] In actual harvesting operations in the fields, such as Figure 19 As shown, it is not uncommon for a combination of reciprocating and vortex driving modes to exist. Figure 19 In the example, if the combine harvester enters the field (#a), it manually steers to perform a circumferential harvesting motion, forming an outer perimeter area SA (#b) on the outermost edge of the field, which is the harvested area. If the outer perimeter area SA formed by this circumferential harvesting motion reaches a size that allows for directional changes via alpha turns, a vortex driving mode is set for the unharvested area CA, and vortex driving is performed (#c). During this vortex driving, at least straight-line movement can be achieved automatically via automatic steering. The vortex driving continues until the unharvested area CA reaches a size that allows for turning and transfer driving in a reciprocating driving mode (ordinary U-turn, turnaround turn) (#d). Next, for the unharvested area CA, a working driving path is set to cover the unharvested area CA using a reciprocating driving mode (#e). By repeatedly performing reciprocating driving along the set working driving path, the harvesting operation of the field is completed (#f).

[0133] The combine harvester travels automatically along its path while overlapping the ends of the harvest width. Therefore, as... Figure 20Schematic illustration: The path spacing of parallel driving paths can be determined based on the harvest width of the harvesting section 215 and an overlap value set to absorb errors from automatic steering so as not to produce harvesting residue. If the harvest width is set to W and the overlap value is set to OL, then the path spacing D is W-OL. If an overlap value is set, the allowable positional offset range of the harvesting section 215 in the left and right directions is half of the overlap value in each direction.

[0134] If a specified overlap value is set, the allowable range of positional offset is determined. For example... Figure 21 This schematically illustrates that a larger overlap value allows for a wider range of positional offsets. However, a larger allowable range of positional offsets can reduce the precision of steering control. Therefore, in this embodiment, the deviation insensitivity zone is changed based on the overlap value, such that a larger overlap value widens the deviation insensitivity zone. The deviation insensitivity zone refers to the range where lateral positional offsets (lateral position deviations) in both the left and right directions are disabled, and steering control is not performed to eliminate these positional offsets. Therefore, the width Z of the deviation insensitivity zone is obtained as a function F of the overlap value OL, and can be expressed as Z = F(OL). This function F is preferably pre-tabulated. The function F does not need to be continuous; it can also be a step-like function.

[0135] like Figure 22 As shown, when transitioning from a turn to the next driving path (i.e., entering the target driving path TL), if the entry deviation between the current vehicle position and the target driving path TL is large, the entry is stopped and the vehicle temporarily reverses. After changing the current vehicle position, the entry is attempted again. This entry deviation includes the lateral offset of the combine harvester 210 relative to the target driving path TL when the combine harvester 210 has moved within a specified distance from the starting point of the target driving path TL, and the azimuth offset between the direction of travel of the combine harvester and the target driving path TL, i.e., the entry angle θ. When the combine harvester 210 has moved within a specified distance from the starting point of the target driving path TL, this lateral offset is not so large. Therefore, in this embodiment, only the entry angle θ is treated as the entry deviation. Of course, both the lateral offset and the entry angle θ can be treated as the entry deviation.

[0136] If the machine 210 approaches the starting point of the target travel path, but the entry angle θ still exceeds the limit angle θL that prohibits entry, the entry is aborted and a retry is performed. In this retry, the machine 210 temporarily reverses to align its orientation with the target travel path, and then switches to forward motion to enter the target travel path TL.

[0137] In this embodiment, the configuration is such that if the overlap value OL increases, thereby allowing a larger range of positional offset, the limiting angle θL also increases. That is, the limiting angle θL is obtained by a function G of the overlap value OL, and can be expressed as θL = G(OL). This function G does not need to be a continuous number, and can also be a step-like function.

[0138] Figure 23 The control system of the combine harvester is shown. The control system of the combine harvester includes a control unit 205 consisting of multiple electronic control units (ECUs) connected via an onboard LAN, and various input / output devices that communicate with the control unit 205 via signals and data.

[0139] The control device 205 serves as an input / output interface and includes an output processing unit 258 and an input processing unit 257. The output processing unit 258 is connected to various motion devices 270 via a device driver 265. The motion devices 270 include travel-related equipment (i.e., a travel equipment group 271) and work-related equipment (i.e., a work equipment group 272). The travel equipment group 271 includes, for example, an engine, transmission, braking, and steering system. The work equipment group 272 includes a harvesting device (…). Figure 12 The control equipment in the harvesting section 215, threshing device 213, conveying device 216, grain discharge device 218, etc. shown.

[0140] The input processing unit 257 is connected to a driving status sensor group 263, an operation status sensor group 264, and a driving operation unit 290. The driving status sensor group 263 includes a vehicle speed sensor, an engine speed sensor, a parking brake detection sensor, a gear shift position detection sensor, and a steering position detection sensor. The operation status sensor group 264 includes sensors for detecting the driving status and attitude of the harvesting device, as well as sensors for detecting the state of the straw and grains.

[0141] The driving operation unit 290 is a general term for any operating component that is manually operated by the driver and whose operation signal is input to the control device 205. The driving operation unit 290 includes a main gear lever 291 (which serves as a gearshift lever), a steering lever 292, a mode operation component that constitutes a mode switching switch 293, and an automatic driving operation component 294. The mode switching switch 293 has the function of sending commands to the control device 205 to switch between automatic and manual driving. The automatic driving operation component 294 requests automatic driving to be initiated through driver input.

[0142] Reporting device 262 is used to report warnings related to the operation status and driving status to the driver, etc., and includes devices such as buzzers and lights. Note that the general terminal 204 also functions as a device that reports the operation status, driving status, and various information to the driver, etc., by displaying them on the touch panel 240.

[0143] The control device 205 is also connected to the general terminal 204 via an onboard LAN. The general terminal 204 is a tablet computer equipped with a touch panel 240. The general terminal 204 includes an input / output control unit 241, a work travel management unit 242, a harvest travel mode selection unit 243, a travel path calculation unit 244, and an overlap value setting unit 245. The input / output control unit 241 also has the function of constructing a graphical interface using the touch panel 240, and the function of exchanging data with a remote computer via wireless lines or the Internet.

[0144] The operation and driving management unit 242 includes a driving trajectory calculation unit 2421, a work area determination unit 2422, and a discharge position setting unit 2423. The driving trajectory calculation unit 2421 calculates the driving trajectory based on the vehicle's position given by the control device 205. The work area determination unit 2422, as shown in the figure... Figure 13 As shown, based on the travel trajectory obtained by the combine harvester circling the outer perimeter area SA of the field several times during harvesting, the field is divided into an outer perimeter area SA and an unworked area CA. The boundary line between the outermost line of the outer perimeter area SA and the field ridge is calculated, and the unworked area CA where automatic travel will take place is calculated using the innermost line of the outer perimeter area SA. The discharge position setting unit 2423 sets the discharge stopping position of the combine harvester when the grain bin 214 is full and the grains in the grain bin 214 are discharged to the transport vehicle CV by the grain discharge device 218. The discharge stopping position is set in the outer perimeter area SA formed on the outer side of the field by circling the field during harvesting, and is located outside the corners of the polygonal outer perimeter area SA.

[0145] The harvest driving mode selection unit 243 allows the driver or operations manager to manually select the harvest driving mode, or automatically selects the harvest driving mode based on input data. Harvesting driving modes include types of driving patterns (reciprocating or vortex driving) and types of turning and shifting (normal U-turn, weir turn, alpha turn). Furthermore, the data considered to determine the detailed control parameters for the harvest driving mode includes field attribute data (area, soil hardness, slope, slippage, etc.), data on the crops to be harvested (rice, wheat, barley, etc.), data on the operating equipment (harvesting width, harvesting speed, etc.), and machine data (minimum turning radius, etc.). This data is displayed on the touch panel 240, allowing the driver or others to manually select the desired harvest driving mode while viewing this data. Alternatively, the harvest driving mode selection unit 243 can automatically select an appropriate harvest driving mode based on this data. This selection of the harvest driving mode can be performed not only at the start of the operation but also during the operation.

[0146] The driving path calculation unit 244 calculates a driving path for automatic driving for the unworked area CA determined by the work area determination unit 2422. If the driver has input that manual driving of the outer perimeter area SA has ended, the path calculation is performed automatically in the selected driving mode.

[0147] The travel path calculation unit 244 determines the interval (path interval) between adjacent travel paths based on the harvesting width (operating width) of the harvesting unit 215 and the overlap value set by the overlap value setting unit 245. Furthermore, the travel path calculation unit 244 utilizes... Figures 16-18 The algorithm described is used to calculate the driving path.

[0148] The overlap value setting unit 245 has the function of determining and setting the overlap value according to the harvest driving mode selected by the harvest driving mode selection unit 243, and the function of setting the overlap value manually input by the driver, administrator, etc.

[0149] The control device 205 includes a vehicle position calculation unit 250, a manual driving control unit 251, an automatic driving control unit 252, a driving path setting unit 253, a control command generation unit 254, an entry deviation calculation unit 255, an operation control unit 256, and a reporting unit 259.

[0150] The vehicle position calculation unit 250 calculates the vehicle's position in map coordinates (or field coordinates) based on positioning data sequentially transmitted from the satellite positioning unit 281. The vehicle position calculation unit 250 can also calculate the vehicle's position using the position vector and travel distance from the inertial navigation unit 282. Furthermore, the vehicle position calculation unit 250 can combine signals from the satellite positioning unit 281 and the inertial navigation unit 282 to calculate the vehicle's position. Moreover, the vehicle position calculation unit 250 can also calculate the vehicle's position based on the past travel direction of the vehicle position calculation unit 210, i.e., the orientation of the unit 210.

[0151] The reporting unit 259 generates report data based on instructions from various functional units of the control device 205 and assigns it to the reporting device 262. When the driving mode is switched to automatic driving mode using the mode switch 293, the control device 205 determines whether automatic driving is permitted based on preset automatic driving permission conditions. If the determination result is permitted, an automatic driving start command is assigned to the automatic driving control unit 252.

[0152] The manual driving control unit 251 and the automatic driving control unit 252 have engine control functions, steering control functions, vehicle speed control functions, etc., and provide driving control signals to the driving equipment group 271. The operation control unit 256 provides operation control signals to the operation equipment group 272 in order to control the operation of the harvesting device.

[0153] This combine harvester can operate in both automatic and manual modes. Automatic mode involves driving the harvester to perform harvesting operations automatically, while manual mode involves driving the harvester to perform harvesting operations manually. When automatic mode is set, the path setting unit 253 receives the path calculated by the path calculation unit 244 from the general terminal 204 and sets it as the path for automatic steering. The automatic driving control unit 252 generates a steering control signal to eliminate azimuth and positional deviations between the path set by the path setting unit 253 and the vehicle position calculated by the vehicle position calculation unit 250. Furthermore, the automatic driving control unit 252 generates control signals related to speed changes based on a pre-set speed value. At this time, the automatic driving control unit 252 is equipped with a system for... Figure 21 The description defines a non-sensitive deviation zone. If the calculated position offset falls within the width of this zone, no position offset correction is performed. The width of the non-sensitive deviation zone changes accordingly with increases or decreases in the overlap value.

[0154] The deviation calculation unit 255 uses the vehicle orientation calculation data sent from the vehicle position calculation unit 250. Figure 22 The entry angle θ is defined as the entry deviation between the target travel path TL (to be entered by turning) and the orientation of the machine 210.

[0155] The control command generation unit 254 generates control commands based on the deviation and overlap between the driving path and the vehicle's position. The control command generation unit 254 is equipped with a function to... Figure 22 The specified limit angle θL is defined as the prohibited deviation. In this embodiment, the control commands generated by the control command generation unit 254 are the following two commands.

[0156] (1) One of the control commands is to change the width of the deviation insensitive zone set in the automatic driving control unit 252 in accordance with the increase or decrease of the overlap value, and this command is given to the automatic driving control unit 252. According to this control command, if the overlap value increases, the width of the deviation insensitive zone increases, and if the overlap value decreases, the width of the deviation insensitive zone decreases.

[0157] (2) Another control command is to terminate the entry into the target driving path TL, which is the driving path to be driven next, when the entry angle θ calculated by the entry deviation calculation unit 255 exceeds the limit angle θL (entry termination command) and to retry the entry, which is given to the automatic driving control unit 252.

[0158] When manual driving mode is selected, if a manual operation signal is sent to the manual driving control unit 251 based on the driver's operation, the manual driving control unit 251 generates a control signal to control the driving equipment assembly 271, thereby realizing manual driving. Note that even in manual driving, the driving path set by the driving path setting unit 253 can be used to guide the combine harvester along that driving path. In addition, the control commands generated by the control command generation unit 254 can also be used for steering control of the manual driving control unit 251.

[0159] [Other embodiments of the second embodiment]

[0160] (1) The overlap value may also be set not on a plot of land, but after the harvesting operation of a part of the plot is completed, in other words, after the local harvesting operation along the prescribed driving path group is completed. At this time, the driving path set in the unoperated area CA at that moment is shifted based on the new overlap value.

[0161] (2) Figure 23 The functional units shown are distinguished primarily for illustrative purposes. In practice, each functional unit may be combined with other functional units, or it may be divided into multiple functional units. For example, the functional units built into the general terminal 204 may be partially or entirely assembled into the control device 205.

[0162] (3) In the above embodiment, the circumferential harvesting is carried out by manual driving, but after the second week, automatic driving may also be used locally, especially for straight-line driving.

[0163] (4) In the above embodiment, a harvester was described that automatically travels along a travel path set in the field while overlapping the ends of the harvest width. However, each functional unit in the above embodiment may also be configured as an automatic steering program for the harvester. Furthermore, the processing performed by each functional unit in the above embodiment may also be configured as an automatic steering method.

[0164] (5) Alternatively, this automatic steering procedure can be recorded on a recording medium.

[0165] (6) In the above embodiments, the application to a full-feed type combine harvester is shown, but the present invention can also be used in a semi-feed type combine harvester. In addition, it can also be used in various harvesters such as corn harvesters, potato harvesters, carrot harvesters, and sugarcane harvesters.

[0166] Explanation of reference numerals in the attached figures

[0167] 10: Body

[0168] 11: Driving device

[0169] 4: General-purpose terminal

[0170] 40: Touch panel

[0171] 41: Input / Output Control Unit

[0172] 42: Operations and Driving Management Department

[0173] 421: Driving trajectory calculation unit

[0174] 422: Work Area Determination Department

[0175] 43: Driving Route Calculation Department

[0176] 44: Turning Path Calculation Department

[0177] 441: Initial Turning Path Calculation Unit

[0178] 442: Later Turning Path Calculation Department

[0179] 443: Enter the path calculation department

[0180] 444: Preliminary Path Calculation Department

[0181] 445: Intermediate Path Calculation Unit

[0182] 5: Control device

[0183] 50: Vehicle Position Calculation Department

[0184] 51: Manual Driving Control Unit

[0185] 52: Automatic Driving Control Unit

[0186] 53: Driving route setting department

[0187] 80: Vehicle position detection module

[0188] C1: Initial turning path

[0189] C2: Later Turning Path

[0190] CA: Area Not in Operation

[0191] Lad: Preparatory path

[0192] Lin: Entry Path

[0193] Lm: Enter the target driving path

[0194] Lmid: intermediate path

[0195] Ln: Enter the starting driving path

[0196] r: radius

[0197] R: radius

[0198] 204: General Terminal

[0199] 205: Control device

[0200] 210: Body

[0201] 242: Operations and Driving Management Department

[0202] 2421: Driving Trajectory Calculation Department

[0203] 2422: Work Area Determination Department

[0204] 2423: Discharge Position Setting Unit

[0205] 243: Harvest Driving Mode Selection Department

[0206] 244: Driving Route Calculation Department

[0207] 245: Overlap value setting unit

[0208] 250: Vehicle Position Calculation Department

[0209] 251: Manual Driving Control Unit

[0210] 252: Automatic Driving Control Unit

[0211] 253: Driving Route Setting Department

[0212] 254: Control Command Generation Unit

[0213] 255: Enter the deviation calculation section

[0214] 280: Vehicle position detection module

[0215] 281: Satellite Positioning Unit

[0216] CA: Area Not in Operation

[0217] CV: Transport vehicle

[0218] D: Arrow

[0219] F: Arrow

[0220] GS: Artificial Satellite

[0221] TL: Enter the target driving path (driving path)

[0222] θ: Entry angle

[0223] θL: Limiting angle

Claims

1. An automatic steering system for a field work vehicle, wherein the field work vehicle automatically travels from an initial driving path to a target driving path via a turning maneuver, wherein... The automatic steering system includes: The initial turning path calculation unit calculates the initial turning path used for the initial turning drive following the initial turning drive along the starting point driving path. The late-turn path calculation unit calculates the late-turn path used for subsequent turns following the initial turn path. The path calculation unit calculates an entry path that connects the later turning path with the target driving path. The turning radius of the initial turning path is set to be larger than the turning radius of the later turning path.

2. The automatic steering system according to claim 1, wherein, At the starting end of the initial turning path, a preliminary path is calculated to extend along the direction of the starting point driving path in order to prevent the field operation vehicle from crushing crops when turning.

3. The automatic steering system according to claim 1 or 2, wherein, The later turning path is an arc. The initial turning path calculation unit calculates the initial turning path as an arc of a circle tangent to the extension of the starting point driving path and the tangent of the later turning path.

4. The automatic steering system according to claim 1 or 2, wherein, The later turning path is an arc. On the rear side of the initial turning path, calculate the straight intermediate path that connects to the later turning path. The initial turning path calculation unit calculates the initial turning path as an arc of a circle tangent to the extension of the starting point driving path and the intermediate path.

5. An automatic steering method for a field work vehicle, wherein the field work vehicle automatically travels from an entry point path to a target path via a turning maneuver, wherein... The automatic steering method includes: The initial turning path calculation step calculates the initial turning path used for the initial turning drive following the initial turning drive along the starting point driving path. The subsequent turning path calculation step calculates the subsequent turning path used for subsequent turning travel following the initial turning path. The entry path calculation step calculates the entry path that connects the later turning path with the entry target driving path. The turning radius of the initial turning path is set to be larger than the turning radius of the later turning path.

6. The automatic steering method according to claim 5, wherein, At the starting end of the initial turning path, a preliminary path is calculated to extend along the direction of the starting point driving path in order to prevent the field operation vehicle from crushing crops when turning.

7. The automatic steering method according to claim 5 or 6, wherein, The later turning path is an arc. In the initial turning path calculation step, the initial turning path is calculated as the arc of a circle that is tangent to the extension of the starting point driving path and the tangent of the later turning path.

8. The automatic steering method according to claim 5 or 6, wherein, The later turning path is an arc. On the rear side of the initial turning path, calculate the straight intermediate path that connects to the later turning path. In the initial turning path calculation step, the initial turning path is calculated as the arc of a circle tangent to the extension of the starting point driving path and the intermediate path.

9. An automatic steering program for a field work vehicle, wherein the field work vehicle automatically drives from an entry point driving path to a target driving path via a turning maneuver, wherein... The automatic steering program enables the computer to: The initial turning path calculation function calculates the initial turning path used for the initial turning drive following the initial driving path from the starting point. The function of calculating the later turning path calculates the later turning path used for later turning driving after driving along the initial turning path. The entry path calculation function calculates the entry path that connects the later turning path with the entry target driving path. The turning radius of the initial turning path is set to be larger than the turning radius of the later turning path.

10. The automatic steering program according to claim 9, wherein, At the starting end of the initial turning path, a preliminary path is calculated to extend along the direction of the starting point driving path in order to prevent the field operation vehicle from crushing crops when turning.

11. The automatic steering procedure according to claim 9 or 10, wherein, The later turning path is an arc. The initial turning path calculation function calculates the initial turning path as the arc of a circle tangent to the extension of the starting point driving path and the tangent of the later turning path.

12. The automatic steering program according to claim 9 or 10, wherein, The later turning path is an arc. On the rear side of the initial turning path, calculate the straight intermediate path that connects to the later turning path. The initial turning path calculation function calculates the initial turning path as an arc of a circle tangent to the extension of the starting point driving path and the intermediate path.

13. A recording medium readable by a computer, wherein, The recording medium records the automatic steering program as described in any one of claims 9 to 12.

14. A harvester that automatically travels along a predetermined path in a field while overlapping the ends of its harvest width, wherein, The harvester has the following features: The harvesting mode selection unit selects the harvesting mode. An overlap value setting unit sets the overlap value of the overlap. The travel path calculation unit calculates the travel path according to the harvest travel mode, in a manner that covers the work object area according to the path interval determined based on the harvest width and the overlap value; The vehicle position calculation unit calculates the vehicle's position. The control command generation unit generates control commands based on the deviation between the driving path and the vehicle's position, as well as the overlap value. An automatic driving control unit performs steering control based on the control commands.

15. The harvester according to claim 14, wherein, The overlap value setting unit changes the overlap value according to the harvest driving mode.

16. The harvester according to claim 14 or 15, wherein, The width of the deviation-insensitive region that invalidates the deviation is changed in a manner that expands in accordance with the increase of the overlap value.

17. The harvester according to claim 14 or 15, wherein, The harvester includes an entry deviation calculation unit that calculates the entry deviation between the target travel path to be entered by turning and the position of the harvester. The control command includes an entry stop command that stops entering the target travel path if the entry deviation exceeds the prohibited deviation. The prohibited deviation changes according to the overlap value.

18. An automatic steering method for a harvester that automatically travels along a predetermined path in a field while overlapping the ends of its harvest width, wherein... The automatic steering method includes: The steps for selecting the harvesting mode of transportation are as follows: Select the harvesting mode of transportation. The overlap value setting step sets the overlap value of the overlap. The driving path calculation step calculates the driving path according to the harvest driving method, in a manner that covers the work object area according to the path interval determined based on the harvest width and the overlap value; The steps for calculating the vehicle's position are as follows: The control command generation step generates control commands based on the deviation between the driving path and the vehicle's position, as well as the overlap value. The automatic driving control steps involve steering control based on the control commands.

19. The automatic steering method according to claim 18, wherein, In the overlap value setting step, the overlap value is changed according to the harvest driving mode.

20. The automatic steering method according to claim 18 or 19, wherein, The width of the deviation-insensitive region that invalidates the deviation is changed in a manner that expands in accordance with the increase of the overlap value.

21. The automatic steering method according to claim 18 or 19, wherein, The automatic steering method includes an entry deviation calculation step, which calculates the entry deviation between the target driving path to be entered by turning and the vehicle's position. The control command includes an entry abort command to stop entering the target driving path if the entry deviation exceeds the prohibited deviation, and the prohibited deviation changes according to the overlap value.

22. An automatic steering program for a harvester that automatically travels along a predetermined path in a field while overlapping the ends of its harvest width, wherein... The automatic steering program enables the computer to: The harvest driving mode selection function allows users to choose the harvest driving mode. The overlap value setting function sets the overlap value of the overlap. The driving path calculation function calculates the driving path according to the harvest driving mode, in a manner that covers the work object area according to the path interval determined based on the harvest width and the overlap value; This vehicle location calculation function calculates the vehicle's location. The control command generation function generates control commands based on the deviation between the driving path and the vehicle's position, as well as the overlap value. Automatic driving control function, which performs steering control based on the control commands.

23. The automatic steering program according to claim 22, wherein, The overlap value setting function changes the overlap value according to the harvest driving mode.

24. The automatic steering program according to claim 22 or 23, wherein, The width of the deviation-insensitive region that invalidates the deviation is changed in a manner that expands in accordance with the increase of the overlap value.

25. The automatic steering program according to claim 22 or 23, wherein, The automatic steering program includes an entry deviation calculation function, which calculates the entry deviation between the target driving path to be entered by turning and the vehicle's position. The control command includes an entry abort command to stop entering the target driving path if the entry deviation exceeds the prohibited deviation. The prohibited deviation changes according to the overlap value.

26. A recording medium readable by a computer, wherein, The recording medium records the automatic steering program as described in any one of claims 22 to 25.

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