Tractor

Abstract

To provide a tractor capable of appropriate display.SOLUTION: The display portion indicates the deviation of the orientation of the machine body with respect to the target traveling route by displaying the target traveling route after the machine body has moved along the target traveling route among the plurality of target traveling routes by coloring the periphery of the target traveling route with a color indicating that the movement has been completed, displaying the periphery of the other target traveling routes with a color different from the coloring, and performing a circular display 83 beside a portion where the plurality of target traveling routes are displayed.SELECTED DRAWING: Figure 13

Description

[Technical Field]

[0001] The present invention relates to a tractor. [Background technology]

[0002] For example, the work vehicle disclosed in Patent Document 1 is equipped with a position detection unit (referred to as a "receiving device" in the document) that can acquire position information about the vehicle using a satellite positioning system, and a steering control unit (referred to as an "automatic steering control unit" in the document) that can control the steering of the vehicle along a target heading based on the position information acquired by the position detection unit. Furthermore, the target heading that serves as the basis for automatic steering control is set based on the positions of an operating tool that registers a start point (referred to as a "start point registration switch" in the document) and an operating tool that registers an end point (referred to as an "end point registration switch" in the document) when each is operated. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Laid-Open No. 2018-148858 Summary of the Invention [Problem to be solved by the invention]

[0004] In the work vehicle disclosed in Patent Document 1, the start point and the end point are registered using separate, dedicated operating tools. With this configuration, there is a risk that the occupant will press the wrong operating tool when registering the start point and the end point, which would make the operation of registering the start and end points cumbersome for the occupant. Furthermore, if the operating tool could be used as another operating means in addition to setting the start and end points, the number of operating tools would be reduced, which would be advantageous in terms of cost.

[0005] An object of the present invention is to provide a tractor capable of providing appropriate display. [Means for solving the problem]

[0006] The tractor according to the present invention includes a body equipped with a traveling device, a position detection unit capable of detecting position information of the body based on a positioning signal from a navigation satellite, and a reference path generating unit that generates a reference path; and a steering control unit capable of steering the traveling device; ,of Preparation, The reference path generating unit is configured so that a start point is set by operating a control tool, and after the machine travels a predetermined distance after setting the start point, an end point can be set by operating the control tool. .

[0007]

[0008] In the present invention, The display unit is provided with a display unit that displays a plurality of lines along the reference route and a machine symbol while the machine is moving, the display unit displays the machine symbol including the machine displayed with an arrow pointing in the direction of travel and a work implement displayed behind the arrow, the display unit displays at least a plurality of lines along the reference route that the machine has not yet traveled, and the display unit, in a state where it displays a line along the reference route that the machine has already traveled, colors the periphery of the line along the reference route that has already been traveled with a width corresponding to the work width of the work implement, so that the line along the reference route that has not yet been traveled and the line along the reference route that has already been traveled can be distinguished. This is preferable.

[0009]

[0010]

[0011]

[0012]

[0013]

[0014]

[0015]

[0016]

[0017] [Brief explanation of the drawings]

[0018] [Figure 1] FIG. 1 is a side view of a tractor as a traveling work machine. [Figure 2] FIG. 2 is a diagram showing panels at the front of the driver's cab interior. [Figure 3] FIG. 2 is a functional block diagram showing the functions and data flow of automatic steering control. [Figure 4] FIG. 1 is a plan view of a farm field, schematically illustrating a travel path during tillage work by a tractor. [Figure 5] FIG. 10 is a flowchart illustrating a process for generating a reference trajectory. [Figure 6] FIG. 10 is an explanatory diagram showing guidance information when generating a reference route. [Figure 7]FIG. 10 is a flowchart showing a process for displaying guidance information when turning; [Figure 8] FIG. 10 is an explanatory diagram showing guidance information when turning; [Figure 9] FIG. 10 is an explanatory diagram showing guidance information when turning; [Figure 10] FIG. 10 is an explanatory diagram showing guidance information when turning; [Figure 11] FIG. 10 is an explanatory diagram showing guidance information when turning; [Figure 12] FIG. 10 is a flowchart showing a process for displaying guidance information before automatic steering control is started. [Figure 13] FIG. 4 is an explanatory diagram showing guidance information before the start of automatic steering control. DETAILED DESCRIPTION OF THE INVENTION

[0019] [Basic configuration of traveling work equipment] An embodiment of a traveling work machine according to the present invention will be described. FIG. 1 shows a side view of a tractor, an example of a traveling work machine. This tractor has a riding section 15 provided in the center of a body 1 supported by front and rear wheels 11 and 12, which serve as a traveling device. A rotary tiller 3, serving as a working device, is attached to the rear of the body 1 via a hydraulic lifting mechanism. The front wheels 11 function as steering wheels, and changing their steering angle changes the traveling direction of the tractor. The steering angle of the front wheels 11 is changed by operation of a steering mechanism 13. The steering mechanism 13 includes a steering motor 14 for automatic steering control. A panel assembly 17 is provided at the front of the riding section 15, and a steering wheel 16, serving as a steering operation tool, is located adjacent to and rearward of the panel assembly 17. Although not described in detail, a recess is provided in the left-right center of the rear of the panel assembly 17, and the recess is recessed further forward of the body than the left and right sides of the panel assembly 17. The steering wheel 16 is supported by a steering post 22 serving as a support member, and the front part of the steering post 22 is located in a recessed portion. When the vehicle is driven manually, the front wheels 11 are steered by manually operating the steering wheel 16.

[0020] In this invention, "steering operation" means changing the direction of the body 1 by changing the direction of the front wheels 11, but if the running device is a crawler type, changing the direction of the body 1 by the speed difference between the left and right crawlers is also included in "steering operation."

[0021] 2, the panel assembly 17 is provided with a meter panel 20 and a side panel 21 arranged vertically, with the side panel 21 being disposed above the meter panel 20. The meter panel 20 displays information related to the operation of the vehicle 1, such as the engine RPM and remaining fuel level. The side panel 21 displays guidance information for the automatic steering control, which will be described later. The meter panel 20 and the side panel 21 are configured as part of the display unit 4 in the configuration of the automatic steering control.

[0022] A dial switch 23 is disposed on the upper surface of the steering post 22. The side panel 21 is configured to be operable using the dial switch 23 as an operating tool, and the dial switch 23 is disposed on the upper part of the steering post 22 and directly below the steering wheel 16. The dial switch 23 is configured to be rotatable about an axis in the vertical direction (or in a direction tilting upward toward the rear in the longitudinal direction of the vehicle), and the passenger can change the items of guidance information displayed on the side panel 21 by turning the dial switch 23. The dial switch 23 is also configured to be depressed downward (or in a direction tilting downward toward the front in the longitudinal direction of the vehicle). The passenger can confirm the setting items or selection items related to the guidance information displayed on the side panel 21 by pressing the dial switch 23. The dial switch 23 also serves as a trigger switch 49, which will be described later with reference to FIG. 3 etc., and is operated as the trigger switch 49 when the passenger presses the dial switch 23. Hereinafter, the dial switch 23 will be referred to as the "trigger switch 49."

[0023] [Configuration of automatic steering control] Next, the configuration for performing automatic steering control will be described. As shown in Figure 3, the vehicle 1 is equipped with a control device 75 consisting of a number of electronic control units called ECUs (Electronic Control Units). The control device 75 is configured to be able to switch control modes between an automatic steering mode in which automatic steering control is performed, and a manual steering mode in which automatic steering control is not performed.

[0024] The aircraft 1 is equipped with a satellite positioning unit 8a that uses a well-known technology, GPS (Global Positioning System), as an example of a satellite positioning system (GNSS: Global Navigation Satellite System) that receives radio waves from satellites to detect the position of the aircraft 1. In this embodiment, the satellite positioning unit 8a uses DGPS (Differential GPS: relative positioning method), but RTK-GPS (Real Time Kinematic GPS: interferometric positioning method) can also be used.

[0025] Specifically, the aircraft 1, which is the target of positioning, is equipped with a satellite positioning unit 8a, which is one component of the position detection unit 8. The satellite positioning unit 8a receives, via an antenna, radio waves transmitted from multiple GPS satellites orbiting the Earth. The position of the satellite positioning unit 8a is determined based on information on the radio waves received from the navigation satellites.

[0026] In addition to the satellite positioning unit 8a, the aircraft 1 is equipped with an inertial measurement unit 8b having, for example, an IMU (Inertial Measurement Unit) as orientation detection means for detecting the orientation of the aircraft 1. The inertial measurement unit 8b may be configured to include a triaxial gyro sensor or a triaxial acceleration sensor. Although not shown, the inertial measurement unit 8b is provided, for example, at a low position in the center of the aircraft 1 in the width direction. The inertial measurement unit 8b can detect the angular velocity of the turning angle of the aircraft 1 and can calculate the change in the azimuth angle of the aircraft 1 by integrating the angular velocity. Therefore, the measurement information measured by the inertial measurement unit 8b includes orientation information of the aircraft 1. Although not described in detail, the inertial measurement unit 8b can measure not only the angular velocity of the turning angle of the aircraft 1, but also the angular velocity of the left-right tilt angle of the aircraft 1 and the forward-backward tilt angle of the aircraft 1.

[0027] The control device 75 includes a route setting unit 76, a heading deviation calculation unit 77, a travel trajectory acquisition unit 78, a control unit 79, and a steering control unit 80. The route setting unit 76 sets a target travel route LM (see FIGS. 4, 8, etc.) along which the vehicle 1 should travel. The heading deviation calculation unit 77 is configured to calculate the angular deviation between the traveling direction of the vehicle 1 and the target direction LA, i.e., the heading deviation. The control unit 79 calculates and outputs an operation amount based on the heading deviation information so that the vehicle 1 travels along the target travel route LM. Note that the control unit 79 can also calculate and output an operation amount based on position information of the vehicle 1 measured by the satellite positioning unit 8a and heading information of the vehicle 1 measured by the inertial measurement unit 8b, in addition to the heading deviation information. The steering control unit 80 controls the steering motor 14 based on the operation amount. Note that the control unit 79 and the steering control unit 80 may be configured integrally.

[0028] A trigger switch 49 is provided as an operating tool for setting a target travel path LM (see Figures 4, 8, etc.) used for automatic steering control and starting automatic steering control. As will be described in detail later, the target travel path LM is set based on a target orientation LA (see Figure 4), which is calculated based on a travel path that the machine body 1 has previously traveled through a field. The setting of a start position Ts (see Figure 4) and an end position Tf (see Figure 4) for travel to obtain the travel path is performed by operating the trigger switch 49. Note that the trigger switch 49 does not have to be configured as a single switch, and may be configured so that a switch for setting the start position Ts and a switch for setting the end position Tf are provided side by side.

[0029] Information from the satellite positioning unit 8a, the inertial measurement unit 8b, the trigger switch 49 as an operating tool, the steering angle sensor 60 as a steering operation detection means, the torque sensor 61, the vehicle speed sensor 62, the obstacle detection unit 63, and the like is input to the control device 75. The vehicle speed sensor 62 is configured to detect the vehicle speed, for example, from the rotational speed of a transmission shaft in the transmission mechanism for the rear wheels 12. Note that the vehicle speed may be detected not only by the vehicle speed sensor 62 but also by a positioning signal from the satellite positioning unit 8a. The obstacle detection units 63 are provided at the front and on both the left and right sides of the vehicle body 1 and are, for example, optical distance sensors or image sensors, and are configured to be able to detect the edges of fields, steel towers within the field, and the like. When an obstacle is detected by the obstacle detection unit 63, an alarm is issued to the occupant by an alarm unit 64, for example, a buzzer or voice guidance. The control device 75 is also connected to the notification unit 59, which is configured to notify the user of conditions such as vehicle speed and engine RPM. The notification unit 59 is configured to be displayed on the display unit 4, for example. The alarm unit 64 may be configured to display an alarm on the display unit 4 via the notification unit 59. In this case, for example, an alarm for detecting a ridge is displayed on the display unit 4. The alarm unit 64 may be configured as a part of the notification unit 59. The display unit 4 is configured to be able to display various information on the screen based on signal inputs from the notification unit 59 and the alarm unit 64. The display unit 4 is also configured to be able to display various types of guidance information depending on the state of the machine 1 when it is traveling straight ahead or turning, etc.

[0030] The azimuth deviation calculation unit 77 calculates the angular deviation, i.e., the azimuth deviation, between the detected azimuth of the aircraft 1 detected by the satellite positioning unit 8a and the inertial measurement unit 8b and the target azimuth LA along the target driving path LM. When the control device 75 is set to the automatic steering mode, the control unit 79 calculates and outputs the operation amount for controlling the steering motor 14 so as to reduce the angular deviation. In this way, the steering control unit 80 is configured to be able to steer and control the aircraft 1 along the target azimuth LA.

[0031] The traveling trajectory acquisition unit 78 calculates the position of the aircraft 1, i.e., the aircraft's own position NM, based on the positioning signal measured by the satellite positioning unit 8a, the orientation of the aircraft 1 calculated by the orientation deviation calculation unit 77, and the vehicle speed detected by the vehicle speed sensor 62. The memory unit 81 is configured to be able to store the aircraft's own position NM as position information. The traveling trajectory acquisition unit 78 stores the aircraft's own position NM over time in the memory unit 81, which is configured, for example, by RAM (random access memory). The traveling trajectory acquisition unit 78 is also configured to be able to acquire a traveling trajectory based on a set of the aircraft's own positions NM stored in the memory unit 81. In short, the traveling trajectory acquisition unit 78 is configured to be able to acquire the traveling trajectory of the aircraft 1 based on the detection of the aircraft's own position NM as position information over time.

[0032] The control unit 79 calculates the amount of operation based on the information on the azimuth deviation. During automatic steering control of the aircraft 1, the steering control unit 80 executes automatic steering control based on the amount of operation output by the control unit 79. That is, the steering motor 14 is operated so that the detected position of the aircraft 1 (aircraft position NM) detected by the satellite positioning unit 8a and the inertial measurement unit 8b becomes a position on the target driving route LM.

[0033] The control signal in this embodiment may be the amount of operation output by the control unit 79, or may be a voltage value or current value with which the steering direction control unit 80 operates the steering motor 14.

[0034] The path setting unit 76 includes a reference path setting unit 76A, a target orientation calculation unit 76B, and a target driving path setting unit 76C. As shown in FIG. 3, a reference path corresponding to a target path to be automatically steered is set by the reference path setting unit 76A through a reference path setting process based on the operation of the trigger switch 49. The target orientation calculation unit 76B calculates a target orientation LA based on an orientation along the longitudinal direction of the reference path. The target driving path setting unit 76C is configured to generate a target driving path LM along the target orientation LA based on the reference path and the target orientation LA. To generate the target driving path LM, the path setting unit 76 includes a start position calculation unit 76D, an end determination unit 76E, and a distance calculation unit 76F. The start position calculation unit 76D, the end determination unit 76E, and the distance calculation unit 76F will be described later. The reference path setting unit 76A and the target orientation calculation unit 76B may be configured integrally.

[0035] [Target driving route] FIG. 4 shows a schematic diagram of an example of tillage work using a tractor. In this tillage work, work travel, in which the tractor advances along a linear work path while performing actual tillage work, and turning travel, in which the tractor turns to transition to the next linear work path, are repeated multiple times. The first linear work path is a reference path that is manually steered, and the subsequent linear paths are sequentially set by the path setting unit 76 to run parallel to the reference path. These paths are target travel paths LM for automatic steering control, and FIG. 4 shows multiple target travel paths LM1-LM6. Work travel with automatic steering control is performed on each of the target travel paths LM1-LM6. As the machine body 1 travels between each of the target travel paths LM1-LM6, it reverses direction from the end position Lf of the work travel to the start position Ls of the next work travel in an unworked area of ​​the field.

[0036] First, a reference path is generated. The rider manually moves the machine 1 to a ridge at one corner of the field. When the machine 1 reaches the ridge at one corner, the rider operates the trigger switch 49. The position at which the rider operates the trigger switch 49 is registered as the start position Ts by the reference path setting unit 76A. After the start position Ts is registered, the rider manually moves the machine 1 straight (or approximately straight) from the start position Ts along the ridge at one side of the field. During this time, the traveling trajectory acquisition unit 78 calculates the machine's position NM over time and stores it in the memory unit 81. Then, after the machine 1 has moved straight (or approximately straight) from one end of the ridge to the other, the rider stops the machine 1 and operates the trigger switch 49 again. Then, the position at which the rider operates the trigger switch 49 again is registered as the end position Tf by the reference path setting unit 76A. The travel trajectory acquisition unit 78 acquires a travel trajectory based on a set of aircraft positions NM between the start position Ts and the end position Tf, and the reference path setting unit 76A calculates a reference path between the start position Ts and the end position Tf based on this travel trajectory. When the aircraft 1 travels along the target travel path LM, the direction along this reference path becomes the target orientation LA.

[0037] The travel of the machine 1 between the start position Ts and the end position Tf may be a work travel involving tilling work, or a non-work travel. When the position coordinates of the reference path are set, it is also possible to perform automatic steering control on at least a part of this reference path.

[0038] After completing the setting of the reference path, the rider moves the vehicle 1 to the start position Ls of the target area of ​​the first work trip in the field. In the embodiment shown in FIG. 4, since the target area of ​​the first work trip is adjacent to the reference path, the rider performs a turning trip, reversing the vehicle's direction of travel 180 degrees, in order to move the vehicle 1 to the start position Ls. At this time, the control unit 79 can determine that the vehicle 1 has turned by the reversal of the vehicle's orientation. The reversal of the vehicle's orientation can be detected by the satellite positioning unit 8a or the inertial measurement unit 8b. The turning of the vehicle 1 may be determined by the operation of various devices other than the reversal of the vehicle's orientation. For example, the operation of various devices may be a configuration in which the clutch of the PTO shaft is turned on and off. Furthermore, the arrival of the vehicle 1 at the start position Ls may be determined by the satellite positioning unit 8a.

[0039] After this turning is completed, the manual steering mode of the control device 75 continues, and the rider manually drives the machine body 1 along the target heading LA. During this time, the control device 75 checks the heading deviation of the machine body 1 calculated by the heading deviation calculation unit 77, the direction of the front wheels 11, the steering angle of the steering wheel 16, and other discrimination conditions to determine whether the state of the machine body 1 is suitable for the next tilling operation. Whether the state of the machine body 1 is suitable for tilling operation is determined, for example, based on whether the running deviation of the machine body 1 in the left-right direction relative to a reference position that is an integer multiple of the working width from the position before the turning in a direction perpendicular to the target heading LA is within an allowable range. If the running deviation is outside the allowable range, the rider manually steers the machine body 1 so that the running deviation of the machine body 1 is within the allowable range.

[0040] Examples of conditions that are unsuitable for tillage work include when the azimuth deviation of the machine body 1 from the target azimuth LA is significantly large, when the steering wheel 16 is continuously steered left and right and the position of the steering wheel 16 is unstable, or when the vehicle speed of the machine body 1 is too fast or too slow. Another example of a condition that is unsuitable for tillage work is when the detection accuracy of the position detection unit 8 is lower than a preset threshold value.

[0041] When the control device 75 determines that the state of the machine body 1 is suitable for the next tillage operation, automatic steering control becomes possible by operating the trigger switch 49. That is, when the rider operates the trigger switch 49, the target travel path LM1 is set by the target travel path setting unit 76C, and work travel begins. When work travel begins, automatic steering control is performed so that the machine body 1 travels along the target travel path LM1. The target travel path LM1 is set in a direction along the target orientation LA, and is the target travel path LM along which the machine body 1 will first travel for work after the reference path is set. While automatic steering control is being performed, automatic steering is performed by operation of the steering mechanism 13, and the vehicle speed of the machine body 1 is also automatically adjusted. Note that even while automatic steering control is being performed, the vehicle speed of the machine body 1 may be configured to be adjusted manually by the rider.

[0042] When automatic steering control along target travel path LM1 is completed, the rider continues manual steering after the turning travel described above until the state of the machine body 1 becomes suitable for the next tilling work. If operation of the trigger switch 49 is permitted, the rider operates the trigger switch 49, and the target travel path setting unit 76C sets the next target travel path LM2 in an orientation that follows the target orientation LA. Then, automatic steering control is performed so that the machine body 1 travels along the target travel path LM2. Thereafter, the turning travel, setting of the target travel path LM, and work travel are repeated in the order of target travel paths LM3, LM4, LM5, and LM6 in the above-mentioned process.

[0043] [Display of guidance information regarding reference route generation] The display of guidance information related to reference path generation will be described with reference to Figures 3, 5, and 6. The reference path setting unit 76A generates a reference path based on the flowchart shown in Figure 5. Before generating the reference path, the path setting unit 76 determines whether the position detection unit 8 can detect the position information of the aircraft 1 (step #01). If the position information of the aircraft 1 is not detected (step #01: No), a message indicating that detection is not possible is displayed on the display unit 4 (step #02), and the reference path is not generated. In this way, when the accuracy of the position information acquisition by the position detection unit 8 is equal to or higher than a preset accuracy, the reference path setting unit 76A enables the setting of the start position Ts by operating the trigger switch 49 as an operating tool.

[0044] If the position information of the vehicle 1 is detected (step #01: Yes), guidance information for the start position Ts as shown in 6-A of FIG. 6 is displayed on the display unit 4 (step #03), and the start position Ts can be registered. The guidance information shown in 6-A, 6-B, and 6-C of FIG. 6 is displayed on the side panel 21 shown in FIG. 2. Note that this guidance information may also be displayed on the meter panel 20 shown in FIG. 2. In the guidance information for the start position Ts shown in 6-A of FIG. 6, the start position Ts is displayed as "start point A." With the guidance information for the start position Ts displayed on the display unit 4, the system waits for operation of the trigger switch 49 (step #04). When the trigger switch 49 is operated (step #04: Yes), the reference path setting unit 76A registers the start position Ts (start point A) (step #05).

[0045] After registering the start position Ts, the rider manually controls the vehicle 1 to travel a straight line. The reference path setting unit 76A then determines whether the vehicle 1 has traveled a distance equal to or greater than a preset distance by calculating the distance between the start position Ts and the vehicle's own position NM over time (step #06). If the travel distance of the vehicle 1 has not reached the preset distance (step #06: No), even if the rider operates the trigger switch 49, guidance information indicating that the travel distance has not reached the preset distance is displayed on the display unit 4. For example, as shown in FIG. 6B, a message indicating that the travel distance has not reached the set distance may be displayed, such as "Straight travel distance is insufficient." In this way, the reference path setting unit 76A sets the start position Ts (start point A) by operating the trigger switch 49 as an operating tool, and after the vehicle 1 has traveled a preset distance after setting the start position Ts, it becomes possible to set the end position Tf (end point B) by operating the trigger switch 49.

[0046] While the aircraft 1 is moving forward in a straight line due to manual operation, the reference path setting unit 76A also determines whether the aircraft 1 is turning (step #07). The steering angle sensor 60 detects a change in steering operation based on the operation of the steering wheel 16. The aircraft 1 is configured to be able to determine whether it is turning when the change in steering operation based on the detection by the steering angle sensor 60 is detected to exceed a preset range. The azimuth deviation calculation unit 77 can also calculate the turning azimuth of the aircraft 1 based on the positioning signal from the satellite positioning unit 8a and the inertial signal from the inertial measurement unit 8b. When the reference path setting unit 76A determines that the aircraft 1 is turning (step #07: Yes), the registration of the start position Ts is canceled and the generation of the reference path is stopped (step #12). At this time, the display unit 4 displays guidance information indicating that the generation of the reference path has been stopped, such as a message saying, "The generation of the reference path has been terminated because a turn has been detected. Please try generating the reference path again." In this way, after the start position Ts (start point A) is set by operating the trigger switch 49 as an operating tool, if a change in the steering operation is detected to exceed a preset range without the trigger switch 49 being operated, the setting of the start position Ts is canceled.

[0047] If the travel distance of the machine 1 has reached the set distance (step #06: Yes), guidance information for the end point position Tf as shown in 6-C of FIG. 6 is displayed on the display unit 4 (step #08), and it becomes possible to register the end point position Tf. In the guidance information for the end point position Tf shown in 6-C of FIG. 6, the end point position Tf is displayed as "end point B." With the guidance information for the end point position Tf displayed on the display unit 4, the system waits for operation of the trigger switch 49 (step #09). In this way, when it becomes possible to set the end point position Tf (end point B) by operating the trigger switch 49 as an operating tool, the display unit 4 displays that it is now possible to set the end point position Tf.

[0048] When the trigger switch 49 is operated (step #09: Yes), the reference path setting unit 76A registers the end position Tf (step #11). Through the above steps, the reference path is generated and the target orientation LA is calculated. In this way, the reference path setting unit 76A sets the reference path based on the traveling trajectory of the aircraft 1. Furthermore, the trigger switch 49 as an operating tool is configured to be able to set both the start position Ts (start point A) and the end position Tf (end point B) when setting the reference path.

[0049] While waiting for the operation of the trigger switch 49 (step #09: No), the reference path setting unit 76A determines whether the aircraft 1 is turning (step #11) using the same method as in step #07. If it is determined that the aircraft 1 is turning (step #11: Yes), as described above, the registration of the start position Ts is canceled and the generation of the reference path is stopped (step #12), and guidance information indicating that the generation of the reference path has been stopped is displayed on the display unit 4.

[0050] [Display of guidance information when turning] The display of guidance information during turning will be described with reference to Figs. 7 and 11. As shown in Fig. 8, when turning is performed after automatic steering control along the target driving path LM is completed, guidance information regarding turning is displayed on the display unit 4. Guidance information for turning left, shown in 8-A of Figs. 8 and 9, is displayed on the display unit 4 after automatic driving control is performed along the target driving path LM[n-1]. Guidance information for turning right, shown in 8-B of Figs. 8 and 9, is displayed on the display unit 4 after automatic driving control is performed along the target driving path LM[n]. This guidance information includes a map screen that displays the vehicle 1 and the surroundings of the vehicle 1. Although this guidance information is displayed on the side panel 21 shown in Fig. 2, it may also be displayed on the meter panel 20 shown in the same figure.

[0051] As shown in Fig. 3, the route setting unit 76 includes a start position calculation unit 76D, an end determination unit 76E, and a distance calculation unit 76F. Fig. 7 shows a flowchart relating to the display of guidance information relating to turning, and processing based on this flowchart is performed by the control device 75.

[0052] The end determination unit 76E determines whether the automatic steering control for traveling along the target travel path LM has ended (step #21). The end of the automatic steering control is determined, for example, by whether the PTO clutch lever (not shown) or the pump lever (not shown) has been operated. If the end determination unit 76E determines that the automatic steering control has ended (step #21: Yes), the host vehicle position NM at the time when the end of the automatic steering control was determined is stored in the memory unit 81 as the end position Lf (step #22). The end position Lf is used as work traveling position information WP for the start position calculation unit 76D to calculate the start position Ls2 of the next work traveling. Of the end positions Lf shown in FIGS. 8 to 11, the end position Lf of the target travel path LM[n] is also shown as work traveling position information WP for calculating the start position Ls2 of the next work traveling. In this specification, the start position Ls2 is described separately from the start position Ls, as it is calculated by the start position calculation unit 76D.

[0053] The memory unit 81 stores information about the previous turning run. The start position calculation unit 76D is configured to be able to determine whether the previous turning run was a right turn or a left turn by reading data about the turning run from the memory unit 81. As shown in FIG. 4, when the machine body 1 repeats automatic steering control along the target direction LA, turning runs along the edge of a field generally alternate between right turns and left turns. For this reason, the start position calculation unit 76D determines whether the previous turning run was a right turn or a left turn (step #23). Note that the determination in step #23 may be configured to be performed by a module other than the start position calculation unit 76D. If the previous turning was a right turn (step #23: turn right), before the vehicle 1 starts turning, the start position calculation unit 76D calculates the next start position Ls2 on the left turning side based on the previous turning (step #25-1). Then, guidance information for a left turn is displayed on the display unit 4 (step #25-2), and the display line L2 based on the start position Ls2 is also displayed in this guidance information. Also, if the previous turning was a left turn (step #23: turn left), before the vehicle 1 starts turning, the start position calculation unit 76D calculates the next start position Ls2 on the right turning side based on the previous turning (step #24-1). Then, guidance information for a right turn is displayed on the display unit 4 (step #24-2), and the display line L2 based on the start position Ls2 is also displayed in this guidance information.

[0054] In this way, when the end determination unit 76E determines that the work drive has ended, the start position calculation unit 76D calculates a start position Ls2 to either the left or right of the traveling direction of the machine 1 for the work drive based on the work drive position information WP as position information, and the display unit 4 displays guidance information that guides the machine 1 to turn to the start position Ls2. At that time, if the start position calculation unit 76D calculated the start position Ls in the turning direction to one side, left or right, of the traveling direction in the previous turning drive, the start position calculation unit 76D calculates the start position Ls2 in the turning direction to the other side, left or right, of the traveling direction in the current turning drive, and the display unit 4 displays a display line L2 based on the start position Ls2 on the map screen to the other side, left or right, of the machine 1.

[0055] After the guidance information is displayed on the display unit 4 by the processing of step #24-2 or step #25-2, the passenger operates the steering wheel 16, causing the vehicle 1 to turn. The control device 75 is configured so that the turning direction at this time can be determined by the steering angle sensor 60, which serves as a steering operation detection means (step #24-3, step #25-3). Note that the means for determining the turning direction is not limited to determination by the steering angle sensor 60, and may be, for example, a determination based on a collection of position information of the vehicle 1 measured by the satellite positioning unit 8a, or a determination based on orientation information of the vehicle 1 measured by the inertial measurement unit 8b. In other words, the steering operation detection means may be configured to detect a steering operation by detecting a turn, for example, by the satellite positioning unit 8a or the inertial measurement unit 8b.

[0056] If the actual turning direction of the aircraft 1 differs from the guidance information displayed on the display unit 4, the guidance information displayed on the display unit 4 is changed to guidance information that matches the actual turning direction of the aircraft 1. When guidance information for a right turn is displayed on the display unit 4 (step #24-2), if the actual turning direction of the aircraft 1 is a left turn (step #24-3: turn left), the start position calculation unit 76D calculates the next start position Ls2 on the left turn side (step #24-4). Then, the guidance information on the display unit 4 is changed to guidance information for a left turn (step #24-5). Furthermore, when guidance information for a left turn is displayed on the display unit 4 (step #25-2), if the actual turning direction of the aircraft 1 is a right turn (step #25-3: turn right), the start position calculation unit 76D calculates the next start position Ls2 on the right turn side (step #25-4). Then, the guidance information on the display unit 4 is changed to guidance information for a right turn (step #25-5). In this way, during a turn, when the steering wheel 16 (steering operation tool) is operated in a turning direction opposite to the side on which the start position calculation unit 76D calculated the start position Ls2, the start position calculation unit 76D recalculates the start position Ls2 in the turning direction on the side on which the steering wheel 16 was operated, and the display unit 4 again displays the start position Ls2 on the map screen in the turning direction on the side on which the steering wheel 16 was operated relative to the vehicle 1.

[0057] Before describing step #26 and subsequent steps, a method for calculating the start position Ls2 by the start position calculation unit 76D will be described. In the embodiment shown in FIG. 8, after automatic travel control is performed along the target travel path LM[n], the vehicle's position NM at the time when the end of automatic steering control is determined based on step #22 of FIG. 7 is stored in the memory unit 81 as the terminal position Lf of the target travel path LM[n] (work travel position information WP). Before automatic steering control on the target travel path LM[n], a left turn was performed between the terminal position Lf of the target travel path LM[n-1] and the start position Ls of the target travel path LM[n]. Therefore, a right turn is determined in step #23 of FIG. 7 before the vehicle 1 turns from the terminal position Lf of the target travel path LM[n], i.e., the work travel position information WP.

[0058] In the embodiment shown in FIG. 8, the end position Lf of the target travel path LM[n-1] is separated from the start position Ls of the target travel path LM[n] by a first separation distance P1. The area of ​​work travel based on the target travel path LM[n-1] and the area of ​​work travel based on the target travel path LM[n] are adjacent to each other. Therefore, the first separation distance P1 is the same distance as the working width of the tillage implement 3 attached to the tractor via the PTO shaft, or, for example, a distance that is approximately 10% smaller than the working width of the tillage implement 3. In FIGS. 9 and 11 described below, this first separation distance P1 is as described with reference to FIG. 8. When the first separation distance P1 is a distance smaller than the working width of the tillage implement 3, the working width of the work travel based on the target travel path LM[n-1] and the working width of the work travel based on the target travel path LM[n] overlap by a predetermined width (for example, less than 10% of the working width).

[0059] The end position Lf of the target travel path LM[n-1] is the position where the previous turning travel started. The start position Ls of the target travel path LM[n] is the position where the previous turning travel ended. Furthermore, the end position Lf of the target travel path LM[n-1] and the start position Ls of the target travel path LM[n] are separated by a first separation distance P1. From this, the start position calculation unit 76D estimates that the next automatic steering control will be performed at a position separated by the first separation distance P1 in the lateral direction (a direction perpendicular to the target orientation LA; the same applies below) from the target travel path LM[n]. Then, the start position calculation unit 76D calculates a start position Ls2 of the new work travel to a position separated by the first separation distance P1 in the lateral direction opposite to the side where the target travel path LM[n-1] is located, relative to the work travel position information WP (step #25-1). The target travel route LM[n+1] shown in FIG. 8 is a target travel route LM that is scheduled to be set after the machine body 1 reaches the start position Ls2.

[0060] Then, based on the processing of step #25-2, the right turn guidance information shown in 8-B of Fig. 8 is displayed as a map screen on the display unit 4. In this way, the display unit 4 displays the surroundings of the machine body 1, including the machine body 1, as a map screen. On this map screen, the work travel position information WP and the start position Ls2 of the next work travel are displayed as linear display lines L1 and L2, respectively, along the target heading LA.

[0061] In this way, the start position calculation unit 76D calculates the start position Ls2 based on the distance between the position where the previous turning drive started and the position where the previous turning drive ended, and the display unit 4 displays the start position Ls2 calculated based on the distance in the guidance information.

[0062] The map screen of the guidance information displayed on the display unit 4 schematically shows the aircraft symbol SY and a dashed turning path as shown in FIGS. 8 and 9. While the aircraft 1 is turning, the aircraft symbol SY indicating the position of the aircraft 1 moves along the dashed turning path as shown in the guidance information at 8-B and 8-C in FIG. 9. The display unit 4 displays the turning path of the turning travel on the map screen, but in this embodiment, the turning path is not set in advance, and the dashed turning path is displayed on the map screen as a guide for reaching the start position Ls2. Based on the aircraft's position NM calculated by the traveling trajectory acquisition unit 78, the aircraft symbol SY is displayed as a guide at an arbitrary point on the dashed turning path. Furthermore, the orientation of the aircraft symbol SY changes within the map screen of the guidance information based on the turning direction calculated by the direction deviation calculation unit 77 (see FIG. 3).

[0063] The explanation of the flowchart in FIG. 7 will be resumed. The distance calculation unit 76F (see FIG. 3) is configured to be able to calculate the separation distance between the position information stored in the memory unit 81 and the position information based on the current position of the machine body 1. While the machine body 1 is turning, the separation distance between the work travel position information WP and the machine's own position NM is calculated over time by the distance calculation unit 76F (step #26). In other words, the distance calculation unit 76F calculates the separation distance using the position information when the end determination unit 76E (see FIG. 3) determines that the work travel has ended. The distance calculation unit 76F starts calculating the separation distance after the turning travel has started. Then, as shown in the guidance information 8-B and 8-C in FIG. 9, a separation distance display DF, which is the distance of the component of this separation distance that is perpendicular to the target heading LA, is displayed on the display unit 4 (step #27). In this way, when the end determination unit 76E determines that the work travel has ended, the distance calculation unit 76F calculates the separation distance using work travel position information WP, which is position information based on the work travel for which the end determination unit 76E has determined that the work travel has ended, as position information stored in the memory unit 81. Furthermore, the display unit 4 is configured to be able to display the work travel position information WP and the separation distance display DF. The display unit 4 starts displaying the separation distance after the turning travel has started.

[0064] While the machine body 1 is turning, the control device 75 determines whether the machine body 1 is turning laterally across the start position Ls2 of the next work run and moving away, based on the position information of the machine body 1 measured by the satellite positioning unit 8a (step #28). FIG. 9 shows the machine body 1 turning a distance longer than the first separation distance P1 laterally from the work run position information WP and passing the start position Ls2 of the next work run (shown as the planned start position Ls2' in FIG. 9). The planned start position Ls2' shown in FIG. 9 was the originally set start position Ls2 of the next work run, but the planned start position Ls2' is not used as the start position Ls2 of the next work run. In this case, a Yes determination is made in step #28 of FIG. 7. If the determination in step #28 is Yes, the start position calculation unit 76D calculates a new work travel start position Ls2 at a position away from the planned start position Ls2' by the first separation distance P1 in the horizontal direction opposite to the side where the work travel position information WP is located (step #29). The target travel path LM[n+2] shown in Figure 9 is the target travel path LM that is scheduled to be set after the machine body 1 reaches the start position Ls2.

[0065] FIG. 9 shows a second separation distance P2, which is the distance between the work travel position information WP and the start position Ls2 of the new work travel. The second separation distance P2 is twice the distance of the first separation distance P1. As a result, an unworked area of ​​width equivalent to the working width of the tillage implement 3 is left between the work travel area based on the target travel path LM[n] and the work travel area to be performed based on the start position Ls2 of the new work travel. The width of this unworked area is such that when tilling work is performed, tilling work can be performed without gaps across the already worked areas on both sides. In FIGS. 10 and 11, which will be described later, this second separation distance P2 is as explained based on FIG. 9.

[0066] Furthermore, when the start position calculation unit 76D calculates the start position Ls2 of the new work travel, the right turn guidance information shown in 8-C of FIG. 9 is displayed on the display unit 4 as a map screen based on the processing of step #30. On the map screen shown in 8-C, the work travel position information WP, the planned start position Ls2', and the start position Ls2 of the new work travel are displayed as linear display lines L1, L2', and L2 along the target direction LA, respectively. The display line L2' based on the planned start position Ls2' is located between the display line L1 based on the work travel position information WP and the display line L2 based on the start position Ls2 of the new work travel. Then, as a guide for reaching the start position Ls2 of the new work travel, a dashed turning route is displayed across the display line L1 based on the work travel position information WP and the display line L2 based on the start position Ls2 of the new work travel. The display of the aircraft symbol SY and the display of the separation distance display DF in the guidance information shown in 8-C of Figure 9 are as already described based on the guidance information shown in 8-B of the same figure.

[0067] While the machine body 1 is turning, it is determined whether the orientation deviation between the turning orientation of the machine body 1 calculated by the orientation deviation calculation unit 77 (see FIG. 3) and the target orientation LA is within a preset tolerance range (step #31). If the orientation deviation is outside the tolerance range (step #31: No), the determination process of step #28 and the processes of steps #29 and #30, which are performed when a Yes determination is made in step #28, are repeated. If the orientation deviation is within the tolerance range (step #31: Yes), the distance between the work travel position information WP and the start position Ls2 of the next work travel is stored in the memory unit 81 (see FIG. 3) (step #32), and the process proceeds to the processing of the flowchart shown in FIG. 12, which will be described later. In addition, after the turning travel is completed, the display unit 4 stops displaying the separation distance display DF.

[0068] In the determination in step #31, it may also be determined whether the lateral distance between the work travel position information WP and the vehicle's position NM calculated by the travel trajectory acquisition unit 78 is within a reference distance range based on the work width of the work travel. In this case, in addition to the work width of the work travel, a value that is an integer multiple of this work width may be used as the reference distance, or a value obtained by subtracting the amount of overlap described above from the value that is an integer multiple of this work width may be used as the reference distance.

[0069] Furthermore, the distance stored in memory unit 81 in step #32 may be the actual distance between the work travel position information WP and the start position Ls2 of the next work travel, or it may be a distance that is an integer multiple of a reference distance based on the work width of the work travel and is closest to the actual distance. The distances stored in memory unit 81 in this way are, for example, the first separation distance P1 and the second separation distance P2.

[0070] When turning is performed so that an unworked area of ​​width equivalent to the working width of the tillage implement 3 is left in the horizontal direction between the work travel position information WP and the start position Ls2 of the next work travel (see Figure 9), guidance information such as that shown in Figure 10 is displayed on the display unit 4 during subsequent turning travel. The target travel route LM[n-1] in Figure 10 may be considered to be the same as the target travel route LM[n+2] that is set after the machine body 1 reaches the start position Ls2 in Figure 9.

[0071] In FIG. 10, before automatic steering control on the target driving path LM[n], a left turn was made between the end position Lf of the target driving path LM[n-1] and the start position Ls of the target driving path LM[n]. Guidance information for a left turn, shown in 10-A of FIGS. 10 and 11, is displayed on the display unit 4 after automatic driving control is performed along the target driving path LM[n-1]. Guidance information for a right turn, shown in 10-B of FIGS. 10 and 11, is displayed on the display unit 4 based on the processing of step #24-2 shown in FIG. 7 after automatic driving control is performed along the target driving path LM[n] and before the vehicle 1 actually starts turning. This guidance information includes a map screen displaying the vehicle 1 and its surroundings. While this guidance information is displayed on the side panel 21 shown in FIG. 2, it may also be displayed on the meter panel 20 shown in the same figure.

[0072] The end position Lf of the target travel path LM[n-1] and the start position Ls of the target travel path LM[n] are separated by a second separation distance P2, which is twice (or approximately but less than twice) the working width of the tillage implement 3. As a result, in Figure 10, an unworked area of ​​width equivalent to the working width of the tillage implement 3 is left in the lateral direction between the area of ​​work travel based on the target travel path LM[n-1] and the area of ​​work travel based on the target travel path LM[n]. When tillage work is performed on this unworked area, tillage work is performed seamlessly between the area of ​​work travel based on the target travel path LM[n-1] and the area of ​​work travel based on the target travel path LM[n].

[0073] In the embodiment shown in FIG. 10, during the previous turning, the end position Lf of the target travel path LM[n-1] was separated from the start position Ls of the target travel path LM[n] by a second distance P2. Based on this, the start position calculation unit 76D estimates that the next automatic steering control will be performed at a position laterally separated by the second distance P2 from the target travel path LM[n]. The start position calculation unit 76D then calculates the start position Ls2 of the next work travel to a position laterally opposite the side where the target travel path LM[n-1] is located and separated by the second distance P2 from the work travel position information WP. The target travel path LM[n+1] shown in FIG. 10 is the target travel path LM that is scheduled to be set after the machine body 1 reaches the start position Ls2.

[0074] The guidance information shown in Fig. 10 and 10-B of Fig. 11 shows a display line L1 based on the work travel position information WP and a display line L2 based on the start position Ls2 of the next work travel. In the embodiment shown in Fig. 10, an unworked area of ​​width equivalent to the working width of the tillage implement 3 remains horizontally between the work travel position information WP and the start position Ls2 of the next work travel. Therefore, a display line L3 indicating this unworked area is shown between the display line L1 based on the work travel position information WP and the display line L2 based on the start position Ls2 of the next work travel. The width of this unworked area is such that plowing work can be carried out without gaps across the already worked areas on both sides when plowing work is carried out.

[0075] As described above, the right-turn guidance information shown in 10-B of FIGS. 10 and 11 is displayed on the display unit 4 based on the processing of step #24-2 shown in FIG. 7 after automatic travel control is performed along the target travel path LM[n] and before the vehicle 1 actually starts turning. However, for example, if the target travel path LM[n] is approaching one of the edges of a field ridge along the target direction LA, it is possible that the vehicle 1 cannot actually turn any further to the right based on the work travel position information WP. If the vehicle 1 actually turns left as shown in FIG. 11, a left turn is determined in step #24-3 of FIG. 7, and the guidance information is changed to the left-turn guidance information shown in 10-C of FIG. 11 based on the processing of step #24-5. The start position Ls2 shown in FIG. 10 is shown as the planned start position Ls2′ in FIG. 11, and the planned start position Ls2′ is not used as the start position Ls2 for generating the next target travel path LM.

[0076] In step #24-4 shown in FIG. 7, the start position calculation unit 76D calculates the start position Ls2 for generating the next target travel path LM based on the previous turning travel. Therefore, in principle, the start position calculation unit 76D calculates the start position Ls2 for generating the next target travel path LM to a position that is a second distance P2 away from the work travel position information WP. However, in FIG. 11, the work travel area based on the target travel path LM[n-1] has already been traveled. Therefore, when the vehicle 1 turns left, if the start position Ls2 is calculated to be a position that is a second distance P2 away from the work travel position information WP, this area where work travel has already been completed will overlap with the start position Ls2 of the next work travel. To avoid this inconvenience, the start position calculation unit 76D searches for the start position Ls2 by prioritizing the unworked area on the left turning side. In the embodiment shown in FIG. 11, as described above with reference to FIG. 10, an unworked area remains between the area of ​​work travel based on the target travel route LM[n-1] and the area of ​​work travel based on the target travel route LM[n]. The lateral width of this unworked area corresponds to the work width of the tillage implement 3. Therefore, instead of the planned start position Ls2' shown in FIG. 11, the start position calculation unit 76D calculates the start position Ls2 for generating the next target travel route LM to be a position that is a first separation distance P1 away from the work travel position information WP. The target travel route LM[n+2] shown in FIG. 11 is the target travel route LM that is scheduled to be set after the machine body 1 reaches the start position Ls2.

[0077] [Display of guidance information before starting automatic steering control] After the turning operation is completed, the control device 75 remains in manual steering mode, and the vehicle continues to travel straight ahead under manual control. During this time, the control device 75 checks the heading deviation of the vehicle body 1 from the target heading LA, the direction of the front wheels 11, and the steering state of the steering wheel 16, and determines whether the vehicle is in a state where it can be switched to automatic steering mode. If the vehicle is in a state where it can be switched to automatic steering mode, the control device 75 starts automatic steering control by the passenger operating the trigger switch 49. At this time, the display unit 4 is configured to allow the passenger to visually check whether the control device 75 is in a state where it can be switched to automatic steering mode. At the same time, the display unit 4 displays guidance information to assist the passenger in steering.

[0078] While the work implement continues to travel straight ahead under manual operation, guidance information screens shown in 13-A to 13-D of FIG. 13 are displayed on the display unit 4. These guidance information screens include a map screen displaying the machine body 1 and its surroundings. This guidance information screen is displayed on the side panel 21 shown in FIG. 2, but may also be displayed on the meter panel 20 shown in the same figure. A steering indicator 82 for the steering wheel 16 and a heading deviation indicator 83 for the machine body 1 calculated by the heading deviation calculation unit 77 are displayed vertically at the right edge of the guidance information screen. A map screen including the machine body symbol SY is displayed to the left of the steering indicator 82 and the heading deviation indicator 83 on the screen. A colored drawing WA is displayed on this map screen in the completed tillage area where tillage work has already been completed. The colored drawing WA is calculated based on the set of the machine body position NM stored in the memory unit 81 and the working width of the tillage implement 3. This visually clearly distinguishes the completed and uncompleted areas. The area where the color drawing WA is displayed may be color-coded according to whether the work has been done three or more times, whether it has been done twice, or whether it has been done only once. In other words, the color drawing WA may be color-coded according to the number of work trips, and the already-worked area in the guidance information may be displayed by a different colored color drawing WA. The color drawing WA may also be a pointillist drawing or a pattern drawing.

[0079] The determination of whether to start automatic steering control is performed based on the flowchart shown in FIG. 12. The control device 75 is configured to use a determination counter Ctr to determine whether the vehicle is in a state where it can be switched to automatic steering mode. The value of the counter Ctr is set to zero immediately after the end of turning (step #40). First, it is determined whether the heading deviation of the vehicle 1 is within an allowable range with respect to the target heading LA (step #41). If the heading of the vehicle 1 is tilted to the right with respect to the target heading LA (step #41: tilt right), left turn guidance information shown in 13-A of FIG. 13 is displayed on the display unit 4 (step #43-1). Then, the value of the counter Ctr is reset to zero (step #43-2). The left turn guidance information shown in 13-A of FIG. 13 displays information urging the occupant to turn the steering wheel 16 counterclockwise. If the heading of the aircraft 1 is tilted leftward relative to the target heading LA (step #41: tilt left), the display unit 4 displays right turn guidance information shown in 13-B of Fig. 13 (step #42-1). Then, the value of the counter Ctr is reset to zero (step #42-2). The right turn guidance information shown in 13-B of Fig. 13 displays information urging the passenger to turn the steering wheel 16 clockwise.

[0080] If the aircraft 1 is moving straight in the direction along the target heading LA (step #41: moving straight), the counter Ctr is incremented (step #44), and the value of the counter Ctr increases. Then, it is determined whether the aircraft 1 has traveled a certain distance or more (step #45). Here, the "certain distance" may be a predetermined distance from the start position Ls2 (see Figures 8 to 11), or a predetermined distance from the state in which the aircraft 1 is moving straight in the direction along the target heading LA. If the aircraft 1 has not traveled a certain distance or more (step #45: No), the process returns to step #41.

[0081] If the vehicle 1 has traveled a certain distance or more (step #45: Yes), it is determined whether the change in the steering angle of the steering wheel 16 is maintained within an allowable range (step #46). The steering angle of the steering wheel 16 when automatic steering control is permitted may be, for example, a state in which the steering wheel 16 is not operated in the direction of a right turn or a left turn and the orientation of the front wheels 11 and the orientation of the rear wheels 12 are parallel, but is not limited to this state. For example, if the vehicle 1 is traveling on a terrain that slopes laterally, the vehicle 1 may gradually shift to a lower position in the left-right direction if it simply continues traveling straight. In such a case, by maintaining a state in which the orientation of the front wheels 11 is steered to a higher position in the left-right direction, the vehicle 1 is likely to move forward along the target heading LA. For this reason, the steering angle of the steering wheel 16 when automatic steering control is permitted may also be, for example, a state in which the steering wheel 16 is steered to a right turn or a left turn. In other words, the control device 75 is configured to permit automatic steering control when the turning angle of the steering wheel 16 continues to be maintained within a certain range. If the change in the turning angle of the steering wheel 16 is not maintained within the allowable range (step #46: No), the value of the counter Ctr is reset to zero (step #47). Note that in the processing of step #47, the value of the counter Ctr may be decremented instead of being reset to zero.

[0082] From the time when it is determined in step #41 that the vehicle is traveling straight until the determination in step #46 is made, the display unit 4 displays the guidance information shown in 13-C of FIG. 13. Then, when the counter Ctr reaches a preset value (step #48: Yes), the display unit 4 displays the guidance information shown in 13-D of FIG. 13, and automatic steering control is permitted. Then, when the passenger operates the trigger switch 49, the control mode of the control device 75 is switched from the manual steering mode to the automatic steering mode, and automatic steering control is executed (step #49). Note that if a sharp turn of the steering wheel 16 is detected after the determination in step #48 is Yes but before the passenger operates the trigger switch 49, the value of the counter Ctr may be reset to zero or decremented.

[0083] [Another embodiment] The present invention is not limited to the configurations exemplified in the above-described embodiments, and other representative embodiments of the present invention will be exemplified below.

[0084] (1) In the above-described embodiment, the target orientation calculation unit 76B is configured so that the start position Ts is set by operating the trigger switch 49, and the end position Tf can be set by operating the trigger switch 49 after the aircraft 1 has traveled a predetermined distance after the start position Ts is set. However, this is not limited to this embodiment. For example, the rider may first acquire a travel trajectory by traveling the aircraft 1 for a predetermined distance or more, and then the rider may set the start position Ts and the end position Tf of the acquired travel trajectory. In other words, the trigger switch 49 as a single operating tool may be configured to be able to set both the start position Ts and the end position Tf of the travel trajectory acquired when calculating the target orientation LA.

[0085] (2) In the above-described embodiment, when it becomes possible to set the end position Tf by operating the trigger switch 49, the display unit 4 displays that it is now possible to set the end position Tf, but this is not limited to this embodiment. For example, the display unit 4 may display a warning that it is now possible to set the end position Tf before it becomes possible to set the end position Tf by operating the trigger switch 49. The warning may be, for example, the distance or time until it becomes possible to set the end position Tf.

[0086] (3) In the above-described embodiment, after the start position Ts is set by operating the trigger switch 49, if a change in steering operation is detected that exceeds a preset range without the trigger switch 49 being operated, the setting of the start position Ts is canceled. However, this is not limited to this embodiment. For example, if the rider first acquires a travel trajectory by driving the vehicle 1 for a preset distance or more, the rider may select a region of the travel trajectory excluding the turning region. In this case, the target heading LA is calculated based on the travel trajectory excluding the turning region.

[0087] (4) In the above-described embodiment, steering is performed by changing the direction of the front wheels 11, but steering may be performed by changing the direction of the rear wheels 12. In short, the steering control unit 80 may be configured to be capable of steering the traveling device along the target direction LA.

[0088] (5) As the position detection unit 8 described above, the satellite positioning unit 8a is provided in the vehicle 1, which is the target of positioning, but it is not limited to a configuration in which the positioning signal from the satellite positioning system is directly received. For example, a configuration in which base stations that receive positioning signals from artificial satellites are provided at multiple locations around the work vehicle and the position information of the traveling work machine is determined through network communication processing with the multiple base stations is also possible. In short, the position detection unit 8 may be configured to be able to detect the position information of the vehicle 1 based on the positioning signal from a navigation satellite.

[0089] (6) In the above-described embodiment, the traveling trajectory acquisition unit 78 calculates the aircraft's position NM based on the positioning signal measured by the satellite positioning unit 8a, the orientation of the aircraft 1 calculated by the orientation deviation calculation unit 77, and the vehicle speed detected by the vehicle speed sensor 62, but this is not limited to this embodiment. The traveling trajectory acquisition unit 78 may be configured to calculate the aircraft's position NM based on one (or a combination of two) of the positioning signal, the orientation of the aircraft 1, and the vehicle speed, and acquire the traveling trajectory. In short, the traveling trajectory acquisition unit 78 may be configured to be able to acquire the traveling trajectory of the aircraft 1 based on the detection of position information over time.

[0090] (7) In the above-described embodiment, the trigger switch 49 is a dial switch 23 as an operating tool, but the trigger switch 49 may also be, for example, a pump lever (not shown) that operates the tillage device 3, or a PTO clutch (not shown).

[0091] (8) Note that, although the target travel routes LM1 to LM6 illustrated in Fig. 4 are formed in a straight line, the target travel routes LM1 to LM6 may be formed in a curved line, for example. In this case, the travel trajectory when generating the reference route may be formed in a curved line, and the target orientation LA may be configured to gradually change along this curved line.

[0092] (9) In the above-described embodiment, the steering wheel 16 is shown as the steering operation tool, but the steering operation tool may be, for example, a stick-type lever or a pair of buttons.

[0093] (10) A tractor has been exemplified as a traveling work machine according to the present invention, but the present invention can also be applied to harvesters, rice transplanters, and seed sowing machines in addition to tractors.

[0094] The configurations disclosed in the above-described embodiments (including other embodiments, the same applies hereinafter) can be applied in combination with the configurations disclosed in other embodiments, unless a contradiction arises. Furthermore, the embodiments disclosed in this specification are merely examples, and the present invention is not limited to these, and can be modified as appropriate within the scope of the present invention. [Industrial Applicability]

[0095] The present invention can be applied to a traveling work machine that calculates a target heading based on a travel trajectory and is capable of steering control of the machine body along the target heading. [Explanation of symbols]

[0096] 1: Aircraft 4: Display section 8: Position detection unit 8a: Satellite positioning unit (position detection unit) 11: Front wheel (running gear) 12: Rear wheel (running gear) 15: Boarding section 16: Steering wheel (steering device) 22: Wheel support part (support member) 23: Dial switch (operating device) 49: Trigger switch (operating tool) 60: Steering angle sensor (steering operation detection means) 76B: Target direction calculation unit 78: Driving trajectory acquisition unit 80: Steering control section LA:Target direction Ts: Start position (start point) Tf: End position (end point)

Claims

[Claim 1] A machine body equipped with a running gear; a position detection unit capable of detecting position information of the aircraft based on a positioning signal from a navigation satellite; a travel trajectory acquisition unit capable of acquiring a travel trajectory of the vehicle based on time-series detection of the position information; a target orientation calculation unit that calculates a target orientation based on the travel path; a target travel route setting unit that generates a target travel route based on the target orientation; a steering control unit that can steer the traveling device along the target traveling route; a display unit that displays a plurality of the target travel routes while the vehicle is moving; Equipped with The display unit displays, among the multiple target driving routes, the target driving route after the vehicle has moved along the target driving route by coloring the area around the target driving route with a color indicating that the route has been moved, and displays the areas around the other target driving routes in a color different from the coloring, and indicates the deviation of the vehicle's orientation from the target driving route by displaying a circular shape next to the area displaying the multiple target driving routes.

Images