Work vehicles

Abstract

To provide a work vehicle that can achieve uniform crop growth across fields. [Solution] The system includes a spraying device and a control unit capable of variable spraying based on a spraying map that links the device's own position information acquired by a positioning device with the spraying amount. The spraying map includes first spraying maps 20, 21, 22, and 23 created for each of the multiple fields, and a second spraying map 24 created by combining the multiple fields. The control unit performs variable spraying based on the spraying amounts of the multiple first spraying maps 20, 21, 22, and 23 and the spraying amount of the second spraying map 24.

Description

Technical Field

[0001] The present invention relates to a work vehicle for spraying materials such as fertilizers and pesticides.

Background Art

[0002] Such a work vehicle includes a fertilizer application device and a positioning device for acquiring the position of the vehicle itself, creates a fertilization plan map in which the vehicle position information acquired by the positioning device is linked to the fertilization amount for each field, and performs fertilization while traveling within each field based on the created fertilization plan map.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] Since the fertilization plan map created for each field is created based on the variation in the growth of crops in each field, it is possible to determine the amount (large or small) of fertilization in a plurality of regions within each field, but the variation in the fertilization amount between a plurality of fields is not considered, and the amount (large or small) of relative fertilization across fields cannot be determined. Therefore, uniform growth of crops across fields cannot be achieved.

[0005] Therefore, an object of the present invention is to provide a work vehicle that solves such problems and can achieve uniform growth of crops across fields.

Means for Solving the Problems

[0006] To achieve the above object, a first invention is, A work vehicle comprising a spraying device and a positioning device for acquiring the vehicle's own position, and a control unit capable of variable spraying based on a spraying map that links the vehicle's own position information acquired by the positioning device with the amount of sprayed, The aforementioned spraying map comprises a plurality of first spraying maps created for each of the plurality of fields so as to show the amount to be sprayed in each field, and a second spraying map created so as to show the amount to be sprayed over the entire area of ​​the plurality of fields. The control unit is characterized by performing variable spraying based on the spraying amounts of the plurality of first spraying maps and the spraying amounts of the second spraying map, thereby providing a work vehicle.

[0007] According to the first invention described above, the control unit can determine the relative amount (large or small) of spraying across fields by performing variable spraying based on the spraying amounts in multiple first spraying maps created for each field so that the amount to be sprayed in each of the multiple fields can be determined, and the spraying amounts in a second spraying map created so that the amount to be sprayed over the entire area of ​​the multiple fields can be determined.

[0008] The second invention is, In a work vehicle, the control unit is equipped with a correction means that selects two or more fields from among a plurality of fields in the second spraying map, and corrects the spraying amount of each of the two or more fields in the two or more first spraying maps corresponding to the selected two or more fields based on the spraying amount of the two or more fields, and the control unit is equipped with a correction means that performs variable spraying based on the spraying amount of each of the two or more fields in the two or more first spraying maps corrected by the correction means.

[0009] According to the second invention described above, the relative amount of fertilizer applied across fields can be determined by correcting the application amount of each field in the first spray map corresponding to the two or more selected fields, based on the application amount of two or more fields selected from a plurality of fields in the second spray map that spans multiple fields. Furthermore, since the control unit selects two or more fields from a plurality of fields in the second spray map, the operator (user) is saved the trouble of selecting two or more fields.

[0010] The third invention is, The work vehicle is equipped with a display unit capable of displaying the plurality of first and second spray maps, and the control unit is characterized in that it causes the plurality of first and second spray maps to be displayed on the display unit simultaneously.

[0011] According to the third invention described above, by simultaneously displaying multiple first and second spraying maps on the display unit, it becomes easier to recognize the difference in spraying amounts between fields, making it easier to decide whether to increase or decrease the standard spraying amount.

[0012] The fourth invention is, In the work vehicle, the control unit is characterized by acquiring external shape information for each of the two or more selected fields based on their respective location information, and by comparing the acquired external shape information of the two or more fields, it identifies the field with a larger area and the field with a smaller area.

[0013] According to the fourth invention described above, by identifying large and small fields, the worker can immediately determine which fields are to be sprayed.

[0014] The fifth invention is, In the work vehicle, the control unit is characterized in that the standard spraying amount is the average value obtained by dividing the total amount to be sprayed on the two or more selected fields by the total area of ​​the two or more fields.

[0015] According to the fifth invention described above, by using the average value as the standard application rate, stable crop growth can be expected.

[0016] The sixth invention is, In the work vehicle, each of the fields in the plurality of first spraying maps and each of the plurality of fields in the second spraying map are divided into multiple areas with different areas and spraying amounts, and the control unit is characterized in that, in the two or more selected fields, the spraying amount applied to the area with the largest area among all the areas is set as the standard spraying amount.

[0017] According to the sixth invention described above, by setting the spraying amount in the region with the largest area among all regions as the reference spraying amount, stable growth of the crop can be expected.

[0018] The seventh invention is In a work vehicle, each of the fields of the plurality of first spraying maps and each of the plurality of fields of the second spraying map are divided into a plurality of regions with different areas and spraying amounts, and the control unit sets, in the two or more selected fields, the largest spraying amount or the smallest spraying amount among all regions as the reference spraying amount.

[0019] According to the seventh invention described above, when setting the largest spraying amount among all regions as the reference spraying amount, it is possible to avoid insufficient spraying amounts. Also, when setting the smallest spraying amount among all regions as the reference spraying amount, it is possible to avoid excessive spraying amounts.

[0020] The eighth invention is In a work vehicle, the correction means corrects the spraying amount of each of all the regions by multiplying the reference spraying amount by the ratio set for the spraying amount of each of all the regions.

[0021] According to the eighth invention described above, the correction means multiplies the reference spraying amount by the ratio set for the spraying amount of each of all the regions to correct the spraying amount of each of all the regions, thereby expecting stable growth of the crop.

[0022] The ninth invention is In a work vehicle, the control unit sets the spraying amount that is the median of the spraying amounts of all regions of the two or more selected fields as the reference value, and uses the value obtained by dividing each of the spraying amounts of all regions by the spraying amount that is the median as the ratio.

[0023] According to the above ninth invention, by using the value obtained by dividing the spraying amount of each area by the spraying amount of the median value serving as the reference value as the ratio, the need for an operator (user) to set or select the median value serving as the reference value is eliminated.

[0024] The tenth invention is In a work vehicle, the ratio is characterized in that a plurality of ratios are selected from a list registered in the control unit.

[0025] According to the above tenth invention, by selecting a plurality of ratios from a list registered in the control unit, an operator (user) can arbitrarily set the ratio.

[0026] The eleventh invention is In a work vehicle, when the control unit cannot acquire its own position from the positioning device during spraying, or in case of an abnormality where variable spraying based on the spraying map becomes impossible, the control unit controls to continue spraying with the maximum spraying amount among the spraying amounts sprayed before the abnormality.

[0027] According to the above eleventh invention, when an abnormality occurs during spraying, by continuing spraying with the maximum spraying amount among the spraying amounts sprayed before the abnormality, it is possible to avoid a situation where the spraying amount is insufficient.

Effect of the Invention

[0028] According to the present invention, by causing variable spraying based on the spraying amount of the first spraying map created for each field and the spraying amount of the second spraying map created so as to know the spraying amount for spraying over the entire area of a plurality of fields, it is possible to provide a work vehicle capable of realizing uniform growth of crops across fields.

Brief Description of the Drawings

[0029] [Figure 1] FIG. 1 is a left side view of a work vehicle 1 according to an embodiment of the present invention. [Figure 2]Figure 2 is a control block diagram relating to the control system of the work vehicle 1 shown in Figure 1. [Figure 3] Figure 3 is a schematic plan view of the remote controller used to remotely operate the work vehicle shown in Figure 1. [Figure 4] Figure 4 is an explanatory diagram illustrating the workflow of the work vehicle 1 shown in Figure 1. [Figure 5] Figure 5 is an explanatory diagram illustrating the teaching process described above. [Figure 6] Figure 6 is a diagram showing the round trip in the automatic driving mode described above. [Figure 7] Figure 7 is an explanatory diagram illustrating the automatic adjustment of the planting width during the round trip process described above. [Figure 8] Figure 8 is an explanatory diagram illustrating the inner circumference stroke in the automatic driving mode described above. [Figure 9] Figure 9 is a flowchart for creating a fertilization map. [Figure 10] Figure 10 shows the first fertilization map and the second fertilization map displayed simultaneously on the monitor's display. [Figure 11] Figure 11 shows the amount of fertilizer applied to the two fields in the second fertilization map. [Figure 12] Figure 12(a) shows the variable fertilization setting screen, and Figure 12(b) shows the fertilization setting screen. [Figure 13] Figure 13(a) shows the variable fertilization setting screen, and Figure 13(b) shows the fertilization setting screen. [Modes for carrying out the invention]

[0030] Preferred embodiments of the present invention will be described in detail below with reference to the attached drawings. First, the basic configuration of the work vehicle will be explained below. In this specification, variable rate fertilization (or variable rate spraying) refers to performing fertilization (or spraying) in a field in a variable manner depending on the location, rather than keeping the amount of fertilizer applied (or sprayed) per unit area the same throughout the entire field. In this specification, the basic technology related to variable rate fertilization (or variable rate spraying) will not be explained, but please refer to, for example, Japanese Patent Publication No. 2011-254711.

[0031] <Basic configuration of work vehicles> Figure 1 is a left side view of a work vehicle 1 according to a preferred embodiment of the present invention. As indicated by the arrows in Figure 1, the side of the work vehicle 1 that is in the direction of travel is the front, and the side that is in the opposite direction of travel is the rear. Unless otherwise specified, the left side of the work vehicle 1 in the direction of travel is referred to as "left," and the opposite side as "right."

[0032] The work vehicle 1 according to this embodiment is configured as a so-called rice transplanter, and as shown in Figure 1, it comprises a vehicle body 2 (hereinafter also simply referred to as "vehicle body"), a seedling planting unit 63 attached to the rear of the vehicle body 2, a status indicator light 55 that displays the status of the work vehicle 1, a fertilizer application device (the application device of the present invention) 26 that supplies (spreads) fertilizer as material to the field, a pair of left and right line marking markers 40 that form lines on the field that serve as a guide for the driving position when driving while planting seedlings, a receiving antenna 130 provided on the front of the vehicle body 2, a direction sensor 80 that detects the direction the vehicle body 2 is facing, an auxiliary seedling frame 74 provided on the front of the vehicle body 2 that accommodates seedlings supplied to the seedling planting unit 63, and a remote controller 44 (see Figure 3) that remotely operates the work vehicle 1 from the outside.

[0033] The receiving antenna 130 and the azimuth sensor 80 are covered by the antenna cover 50 shown in Figure 1.

[0034] The receiving antenna 130 is an antenna that receives radio waves from GNSS satellites and constitutes a positioning device that acquires the vehicle's own position information. The vehicle's own position information acquired by the positioning device is transmitted to the navigation ECU 70 of the control unit 87 located on the vehicle body 2 (see Figure 2). RTK-GNSS is used to acquire the vehicle's own position information, and by receiving correction information, highly accurate position information can be acquired.

[0035] In this embodiment, Bluetooth® SPP (Serial Port Profile) is used as the input interface for correction information, and mobile phones and Bluetooth® converters are connected and input by their device names.

[0036] The remote controller 44 shown in Figure 3 allows the operator to remotely control the work vehicle 1. It receives predetermined commands and transmits instructions such as work start, forward / reverse, and stop to a remote control antenna 52 installed on the vehicle. The remote controller 44 also has a display unit 44a capable of displaying various information. This display unit 44a is configured as a touch panel display and can receive operator input and acquire various information. If the remote controller 44 and the work vehicle 1 move beyond the communication distance, the work vehicle 1 recognizes this and is configured to automatically stop for safety.

[0037] As shown in Figure 1, the vehicle body 2 comprises a control unit 87 covered by a front cover 47, a main frame 3 located approximately in the center of the vehicle body 2, a rear frame 6 attached to the rear end of the main frame 3 and extending in the width direction of the work vehicle 1, a floor step 60 located above the main frame 3, a cockpit 48 and control unit 49 located above the floor step 60, an engine 7 located below the cockpit 48, a pair of left and right front wheels 8 (steering wheels) and a pair of left and right rear wheels 9 as driving wheels, and a transmission mechanism such as a transmission case 30 that transmits power from the engine 7 to the pair of left and right front wheels 8 and rear wheels 9.

[0038] The control unit 49 includes a main gear lever 35 for changing the forward and reverse movement and vehicle speed of the vehicle body 2, a steering mechanism 43 including a steering wheel 56 for steering a pair of left and right front wheels 8, a straight assist lever 79 provided near the left side of the steering wheel 56, a monitor 61 with operation switches, and an operation unit 54 equipped with various operation switches for operating the work vehicle 1.

[0039] The straight-ahead assist lever 79 is operated by swinging when starting or stopping the straight-ahead control, which is one of the features of autonomous driving.

[0040] The steering mechanism 43 includes a steering wheel 56, a steering shaft 83, a pitman arm, and tie rods (not shown).

[0041] Meanwhile, the driving force output from the engine 7 is transmitted to the transmission case 30 via a belt-type power transmission mechanism 4 and a hydrostatic continuously variable transmission (HST) 25 located below the floor step 60, as shown in Figure 1.

[0042] The hydrostatic continuously variable transmission 25 is equipped with a trunnion shaft (not shown), and when the main shift lever 35 is operated, the opening of the trunnion shaft is adjusted by the drive of the HST servo motor 150 (see Figure 2), thereby changing the output to the transmission case 30 and adjusting the vehicle speed. When moving forward, that is, when the main shift lever 35 in Figure 1 is in the forward range, the vehicle speed is adjusted to increase as the main shift lever 35 is operated to a more forward position.

[0043] The power transmitted to the transmission case 30 is shifted internally and divided into power for driving to the pair of front wheels 8 and the pair of rear wheels 9, and power for driving the seedling planting unit 63 (driving power).

[0044] Power for driving is transmitted to the left and right pair of front wheels 8 via the front wheel final case 13 and front wheel axle 31 (see Figure 1), and also to the left and right pair of rear wheels 9 via the left and right pair of rear wheel transmission shafts 14, left and right pair of rear wheel gear cases 51 and axle 82 shown in Figure 1.

[0045] On the other hand, the power for driving is transmitted to a planting clutch (not shown) located at the rear of the vehicle body 2, and when the planting clutch is engaged, it is further transmitted to the seedling planting unit 63.

[0046] As shown in Figure 1, the seedling planting unit 63 is attached to the vehicle body 2 via a lifting link device 5. The lifting link device 5 comprises a pair of left and right upper link arms 85 and a pair of left and right lower link arms 86, and is configured to allow the seedling planting unit 63 to move up and down.

[0047] The front ends of the upper link arm 85 and the lower link arm 86 are attached to the link base frame 10, which is fixed to the rear frame 6, and the other ends are attached to the upper and lower link arms 11, which are located below the seedling planting section 63.

[0048] Here, the control unit 87 controls the electronic hydraulic valve 88 (see Figure 2), and when the lifting hydraulic cylinder 12 shown in Figure 1 is retracted hydraulically, the upper link arm 85 rotates upward and backward, causing the seedling planting unit 63 to rise to a non-working position. When the seedling planting unit 63 is in a non-working position, its lower end is at approximately the same height as the bottom of the main frame 3.

[0049] In response, when the lifting hydraulic cylinder 12 is extended hydraulically, the upper link arm 85 rotates downward and backward, and the seedling planting section 63 is lowered to a working position (the position shown in Figure 1) where seedling planting can be performed.

[0050] As shown in Figure 1, the seedling planting section 63 includes a stand 65 for propping up soil-covered mat-shaped seedlings (hereinafter referred to as "seedling mats"), a plurality of planting devices 64 provided behind and below the stand 65, a center float 38 provided at the bottom of the seedling planting section 63, and side floats 39 positioned to the left and right of the center float 38.

[0051] Multiple planting devices 64 are arranged in a line along the width of the work vehicle 1, and each planting device 64 is equipped with two pairs of planting tools 69 arranged in the front-to-back direction. When the planting clutch is engaged and the drive shaft 67 shown in Figure 1 is rotated, the front planting tool 69 and the rear planting tool 69 shown in Figure 1 rotate around the drive shaft 67, alternately picking up seedlings located at the lower end of the stand 65 and planting them in the field.

[0052] The center float 38 and side floats 39 are configured to glide and level the field as the work vehicle 1 moves, and seedlings are planted in the field leveled by each float 38, 39 by each planting device 64. The center float 38 and side floats 39 are each oscillated to conform to the unevenness of the field.

[0053] The pair of line-drawing markers 40 shown in Figure 1 each consist of a line-drawing body 41 that rolls across the field to form a line when the vehicle body 2 is moving, and an L-shaped marker rod 42 in a front view that connects the line-drawing body 41 and the vehicle body 2. The markers are configured to be switchable between an operating position in which the line-drawing body 41 is in contact with the field and a non-operating position in which the line-drawing body 41 is not in contact with the field.

[0054] As the work vehicle 1 travels in a straight line across the field and plants seedlings, the line marking marker 40 on the row where the next seedling will be planted (after the turn) is in the working position while the vehicle travels in a straight line. This creates a line on the field that serves as a guide for the travel position when traveling in a straight line after the turn. Figure 1 shows the left line marking marker 40 in the working position and the right line marking marker 40 in the non-working position.

[0055] As shown in Figure 1, a center mascot 18 is provided at the front and center of the width direction of the work vehicle 1. When the work vehicle 1 turns over the field and travels straight over the next row, the steering wheel 56 is operated so that the center mascot 18 passes along the line formed by the line marking marker 40, and by traveling straight while operating the steering wheel 56, seedlings can be planted in the appropriate position.

[0056] The auxiliary seedling frame 74 is attached to the front of the vehicle body 2 via a frame 77 that supports the auxiliary seedling frame 74, as shown in Figure 1, in order to accommodate seedling mats to be added to the base 65.

[0057] <Control system configuration> As shown in Figure 2, the control unit 87 includes a navigation ECU 70 and a steering ECU 71.

[0058] The navigation ECU 70 calculates the autonomous driving route during work based on position information from GNSS satellites and field shape information, and transmits appropriate steering information to the steering ECU 71 according to that route.

[0059] Furthermore, when the remote control antenna 52 receives an operation signal from the remote controller 44, the operation signal is transmitted to the navigation ECU 70. Based on the operation information obtained from the remote controller 44, the navigation ECU 70 drives the HST servo motor 150 to change the vehicle speed or controls the hydraulic equipment.

[0060] The steering ECU 71 controls the steering motor 57 based on information output from the navigation ECU 70 during autonomous driving. In manual driving mode, a steer-by-wire system is employed, which drives the steering motor 57 based on the steering angle of the steering wheel 56.

[0061] Furthermore, as shown in Figure 2, the input system to the control unit 87 of the work vehicle 1 includes a main gear lever sensor 36 that detects the operating position of the main gear lever 35 (see Figure 1) that changes the forward / reverse movement and vehicle speed of the work vehicle 1, a straight assist lever sensor 81 that detects the operation of the straight assist lever 79 (see Figure 1) which is swung in one direction up or down when acquiring position information of the traveling vehicle body 2, or when starting or stopping straight control, a finger lever sensor 16 that detects the swinging operation of a finger lever (not shown) that raises and lowers the seedling planting unit 63, a planting on / off switch 19 that switches the seedling planting operation on and off, a monitor 61 provided on the traveling vehicle body 2, a marker switch 28 that switches the posture of the left and right line marking markers 40 (see Figure 1), and a turning control switch 17 that sets turning control. The marker switch 28 and the turning control switch 17 are provided on the operation unit 54 (see Figure 1). Furthermore, the system includes a pitman sensor 58 for detecting the steering angle of the steering wheel 56 (see Figure 1), a steering sensor 45 provided on the steering motor 57 for detecting the rotational position and rotational speed of the steering motor 57, an engine speed sensor 96 for detecting the rotational speed of the engine 7, a link sensor 89 for detecting the relative angle of the upper link arm 85 with respect to the link base frame 10, a receiving antenna 130 for receiving radio waves from an artificial satellite, a rear wheel speed sensor 29 for counting the rotational speed of each left and right axle 82 (see Figure 1) connected to the left and right rear wheels 9, a float sensor 33 for detecting the vertical position of the front of the center float 38 (see Figure 1), a compass sensor 80, a tilt detection sensor 37 for detecting the tilt of the vehicle body 2, and a seat switch 110 for detecting seating in the driver's seat 48 (see Figure 1). The finger lever and the gear shift on / off switch 19 are provided on the main gear shift lever 35 shown in Figure 1.

[0062] In this embodiment, the straight-ahead assist lever 79 (see Figure 1) can be swung upward and downward, and after being swung in either the up or down direction, it is configured to automatically return to its original up or down position by a spring.

[0063] As shown in Figure 2, the drive system of the work vehicle 1 includes a throttle motor 97 that adjusts the intake volume of the engine 7 (see Figure 1) located below the driver's seat 48 (see Figure 1), an electronic hydraulic valve 88 that extends and retracts the lifting hydraulic cylinder 12 (see Figure 1) when the seedling planting unit 63 (see Figure 1) is raised and lowered, an HST servo motor 150 that adjusts the opening of the trunnion shaft in the hydrostatic continuously variable transmission 25 (see Figure 1) to change the forward and reverse movement and vehicle speed of the work vehicle 1, a steering motor 57 that rotates the steering shaft 83 and steering wheel 56 shown in Figure 1, an electromagnetic valve 103 that engages and disengages the side clutch of the rear wheel 9 (see Figure 1), a power steering 108, a planting clutch motor 27 that operates the planting clutch, a marker motor 34 that swings each of the left and right line marking markers 40 (see Figure 1), and a fertilizer amount adjustment motor 66 that adjusts the amount of fertilizer applied to the field by the fertilizer application device 26 (see Figure 1).

[0064] The steering motor 57 is controlled by the control unit 87 for the purpose of automatically rotating the steering wheel 56 (see Figure 1) in straight-line control, turning control, and unmanned automatic driving modes.

[0065] Furthermore, the control unit 87 is configured to calculate the current height (vertical position) of the seedling planting unit 63 (see Figure 1) based on the output signal from the link sensor 89.

[0066] In addition, when the work vehicle 1 is driving over the field while planting seedlings, the control unit 87 controls the electronic hydraulic valve 88 based on the detection signal from the float sensor 33 to extend and retract the lifting hydraulic cylinder 12 shown in Figure 1, and raise and lower the seedling planting unit 63 shown in Figure 1, thereby maintaining a constant planting depth for the seedlings in the field.

[0067] <Work process> Figure 4 is an explanatory diagram illustrating the workflow of work vehicle 1. The work process of the work vehicle 1 according to this embodiment consists of four steps: a teaching step (manual), a round-trip step (automatic), an inner circumference step (automatic), and a finishing step (manual). In the first teaching step, an operator rides the vehicle in teaching mode and plants rice along three sides of the outer perimeter of the field H (excluding the side where seedlings are supplied). The receiving antenna 130 acquires position information during the rice planting work, and the control unit 87 uses this information to create a teaching information map (not shown), which represents the shape of the field. Once this teaching information map is created, a planned travel path is calculated based on this map and pre-set information such as the working width, showing the position information of the trajectory of the work vehicle 1's travel path in the subsequent round-trip and inner circumference steps. As a result, the work vehicle 1 is capable of unmanned autonomous driving during the round-trip and inner circumference steps, and performs rice planting in an automated driving manner along the calculated planned travel path. The final step involves workers riding on the remaining outer edge to plant rice seedlings, thus completing the rice planting process.

[0068] More specifically, the process will proceed according to the following steps. (1) Starting The main switch on work vehicle 1 is turned on, the entire system is activated, and the acquisition of the vehicle's position information using the receiving antenna 130 begins. (2) Recognition of azimuth The worker turns the main switch on work vehicle 1 to the start position to start the engine 7 and drives work vehicle 1 approximately 2 meters. This allows work vehicle 1 to recognize its orientation. This process can be done in either forward or reverse and is completed in about 2 meters. Therefore, simply entering the field as usual will complete the recognition of the vehicle's orientation. (3) Preparations for entering the field and teaching The movement from entering the field to the teaching start position (work start position) is the same as with a normal rice transplanter. Furthermore, the adjustment of planting depth and the amount of seedlings to be picked up is the same as with a normal rice transplanter. Since seedlings are actually planted during the teaching process, it is necessary to check the number of seedlings and the amount of fertilizer and herbicide before starting work. Fertilizer is spread based on a spread map (in this embodiment, a fertilizer application map) which links the machine's position information acquired by a positioning device (receiving antenna 130) with the amount of fertilizer to be spread (in this embodiment, the amount of fertilizer applied). (4) Teaching Figure 5 is an explanatory diagram illustrating the teaching process. In addition, teaching is performed when the operator switches from manual operation mode to teaching mode through a predetermined operation, and the control unit 87 executes the necessary processing.

[0069] The teaching process involves manually operating the machine to plant seedlings along the three perimeters (ln1, ln2, ln3) of field H, following the ridges. The machine is raised and lowered manually to ensure no seedlings are missed. During this time, the machine acquires its own position information via the receiving antenna 130, and the resulting teaching route is stored in the control unit 87.

[0070] Once planting is complete on the three outer sides (ln1, ln2, ln3), the system can be switched to automatic operation mode by a predetermined operation performed by the operator. For example, by performing a predetermined operation on the remote controller 44 shown in Figure 3, where the round F switch 441 and the start + round F switch 442 are pressed simultaneously, the control unit 87, which has acquired this operation information, performs the necessary processing to start automatic travel in the round-trip and inner-circuit sections.

[0071] (5) Round trip (autonomous driving) Figure 6 is a diagram showing the round trip route in automatic driving mode. After the teaching process is completed, the worker disembarks from the work vehicle 1 and performs the predetermined operation described above using the remote controller 44 shown in Figure 3. The control unit 87, having acquired the operation information, then performs the necessary processing, and the automatic driving of the work vehicle 1 for the round trip begins.

[0072] During the round trip, the work vehicle 1 is configured to automatically travel back and forth along the planned route, alternating between a straight path and a turning path. When the work vehicle 1 reaches the end of the straight path (the edge of field H), it is controlled to automatically turn along the turning path and enter the next straight path. To ensure space for turning, it automatically reverses about 1 meter before turning. At this time, the seedling planting unit 63 is also raised and lowered automatically (raised when traveling on the turning path and lowered when traveling on the straight path). In this way, during the round trip, the above procedure is repeated, and rice planting is performed automatically while traveling back and forth within field H. Along with the start of this rice planting work, fertilization is also performed based on the fertilization map described later.

[0073] (6) Automatic adjustment of planting width Figure 7 is an explanatory diagram illustrating the automatic adjustment of planting width during the round trip journey. Depending on the size of the field, row stopping or empty running may occur during the second-to-last round trip. The system is configured to automatically perform row stopping and adjust the planting width during the second-to-last outbound or return trip.

[0074] If the stapling operation is performed on the outbound journey, the return journey will skip one leg and run empty. After that, the operation for the final round trip will be performed.

[0075] (7) Inner Circumference Route (Automatic Driving) Figure 8 is an explanatory diagram illustrating the inner circumference stroke in automatic driving mode. Once the automated round-trip journey is complete, the work vehicle 1 transitions to the inner-circuit journey, where it plants while traveling along the remaining inner circumference between the teaching journey and the round-trip journey. At this time, seedlings and fertilizer are supplied and the headland rotor is set as needed.

[0076] Thus, after the inner loop process is completed, seedlings are planted manually in the area between the supply route and the automatically planted section (lower part of the diagram in Figure 8).

[0077] The control unit 87 of the work vehicle 1 is configured to switch between two different modes: a fertilization mode based on a fertilization map created for each field, and a real-time variable fertilization mode. In other words, the control unit 87 is configured to control the fertilization amount adjustment motor 66 with different control amounts in the fertilization mode based on the fertilization map and the real-time variable fertilization mode, respectively. The fertilization mode based on the fertilization map and the real-time variable fertilization mode can be switched at any time by the operator through a predetermined operation (for example, by operating a button on the remote controller 44). Furthermore, since the processing of this fertilization mode and the real-time variable fertilization mode is publicly known technology, its details will not be described here, but please refer to, for example, Japanese Patent Publication No. 2024-024916 and Japanese Patent Publication No. 2024-108376.

[0078] <Creating a scatter map> The procedure for creating a fertilization map (the spread map of the present invention) used in the fertilization mode will be explained using Figures 9 to 11. Figure 9 shows a flowchart for creating a fertilization map. Figure 10 simultaneously displays on the display unit 61A of the monitor 61 multiple first fertilization maps 20, 21, 22, and 23, each created to show the amount of fertilizer to be applied to each of the multiple (four in Figure 9) fields (Field A, Field B, Field C, and Field D), and a second fertilization map 24, which shows the amount of fertilizer to be applied over the entire area of ​​the multiple (four) fields (Field A, Field B, Field C, and Field D). By simultaneously displaying the multiple first fertilization maps 20, 21, 22, and 23 and the second fertilization map 24 on the display unit 61A of the monitor 61 installed on the vehicle body 2, it becomes easier to decide whether to increase or decrease the standard fertilization amount, which will be discussed later. Of the four fields, fields B and C are the largest and have the same area, while field A is smaller than fields B and C. Field D is even smaller than field A, making it the smallest of the four fields. The size of the fields is determined by obtaining external shape information for multiple fields based on their location information, and then comparing the obtained external shape information to identify the larger and smaller fields. In this way, by identifying the first dispersal maps 21 and 22 with large areas and the first dispersal maps 20 and 23 with small areas, the fields to be dispersed can be immediately identified. The control unit 87 can read the fertilizer application amounts (spread amounts) for multiple fields (four in this embodiment) in the second application map 24. As shown in Figure 11, it selects two small fields (field A and field D) from the second application map 24 and displays the fertilizer application amounts for these two fields on the display unit 61A of the monitor 61. In the first and second application maps 20-24, the amount of fertilizer applied is represented by the intensity of the color. That is, the darker the color, the greater the amount of fertilizer supplied, and the lighter the color, the less fertilizer is supplied. In this embodiment, five levels of fertilizer application are represented by the intensity of the color, but it may be set to any number of levels, two or more.In the five stages of fertilizer application, the darkest colored area 1, R1, represents the highest amount of fertilizer, followed by the second darkest area, R2, R3, R4, R4, and R5, R5, R5, R5, R5 is the fifth highest (least) amount.

[0079] Figure 10 shows that the fertilizer application rates (number of shades) in the first fertilization maps 20, 21, 22, and 23, created for each field, differ from the fertilizer application rates (number of shades) in the four fields in the corresponding second fertilization map 24. In the first fertilization map 20, the areas with different fertilizer application rates consist of the first area R1, the second area R2, two third areas R3 and R3, and the fourth area R4 (four shades), whereas in the fields of the second fertilization map 24 corresponding to the first fertilization map 20, the areas with different fertilizer application rates consist of the first area R1 and two second areas R2 and R2 (two shades). This is because the first fertilization maps 20, 21, 22, and 23, created for each field, can determine the amount of fertilizer applied within each field, but they do not take into account the variation in fertilizer application between multiple fields, and therefore cannot determine the relative amount of fertilizer applied across fields. In contrast, the second fertilization map 24 can be created while reflecting the variation in fertilizer application between the four fields, but because it must determine the amount of fertilizer applied over a wide area, it is not possible to improve the accuracy of the fertilizer application determination. Therefore, by looking at the difference in fertilizer application amounts between the first fertilization maps 20, 21, 22, and 23 and the four fields in the second fertilization map 24 corresponding to the first fertilization maps 20, 21, 22, and 23, a decision is made on whether to increase or decrease the standard fertilizer application amount, as described later.

[0080] In this invention, variable fertilization is performed based on the fertilizer application amounts of each of the created first application maps 20, 21, 22, and 23 and the fertilizer application amount of the created second application map 24. Specifically, the fertilizer application amounts of two fields selected from among the multiple (four fields in this embodiment) of the second application map 24 are corrected by a correction means 15 (see Figure 2) provided in the control unit 87 to correct the fertilizer application amounts (field-specific fertilizer application amounts) of the two first application maps 20 and 23 corresponding to those two fields. Variable fertilization is then performed based on the fertilizer application amounts (field-specific fertilizer application amounts) of the first application maps 20 and 23 corrected by the correction means 15. This makes it possible to achieve uniform crop growth across fields.

[0081] Specifically, for example, an aircraft (such as a drone) equipped with imaging means (such as a camera) is flown over each field to capture images of the growth status of crops (rice in this embodiment) in multiple fields (four in this embodiment). Based on the images captured for each field, the control unit 87 divides the growth stage into multiple stages (five in this embodiment) and sets the amount of fertilizer to match each stage, thereby creating first spraying maps 20, 21, 22, and 23 (see step S1 in Figure 9). Furthermore, the growth status of crops (rice in this embodiment) across all four fields is captured by continuously flying an aircraft (such as a drone) equipped with imaging means (such as a camera) over all four fields, and based on the images covering the entire area of ​​all four fields, the control unit 87 divides the growth stage into multiple stages (five in this embodiment) and sets the amount of fertilizer to match each stage, thereby creating a second spraying map 24 (see step S2 in Figure 9). Furthermore, the darker the color, the poorer the crop growth, requiring more fertilizer.

[0082] Next, as shown in Figure 11, the control unit 87 selects two fields from the four fields A, B, C, and D in the second spread map 24 created in Figure 10 (it may also select any number of fields, three or more). In this embodiment, it selects field D, which has the smallest area, and field A, which has the second smallest area (see step S3 in Figure 9). The fertilizer application amounts for the selected fields A and D are stored in the storage unit (not shown). As shown in Figure 11, field A is divided into several (three) areas, and the fertilizer application amount for the first area R1, which has the highest fertilizer application amount, is 48.4 kg / 10a, while the remaining two second areas R2 have the same fertilizer application amount of 44 kg / 10a. Furthermore, in the second application map 24, field D shows multiple (three) areas, with the third area R3 having the highest fertilizer application rate at 40 kg / 10a, the fourth area R4 having the second highest rate at 36 kg / 10a, and the fifth area R5 having the lowest rate at 32.4 kg / 10a.

[0083] The control unit 87 determines the fifth region R5, which has the lowest fertilizer application rate among the five regions R1 to R5, at 32.4 kg / 10a as the standard fertilizer application rate (see step S4), and sets the third region R3, which is the median of the small and large fertilizer application rates in the five regions R1 to R5, at 40 kg / 10a as the reference value for calculating the ratio (see step S5). In other words, the control unit 87 corrects the fertilizer application rate by multiplying the standard fertilizer application rate by five different ratios. Specifically, it sets the reference value of 40 kg / 10a in the third region R3 as a ratio of 1 and calculates the ratios for the first region R1, the second region R2, the fourth region R4, and the fifth region R5. In other words, the first region R1 becomes 48.4 kg ÷ 40 kg = 1.21 times, the second region R2 becomes 44 kg ÷ 40 kg = 1.1 times, the fourth region R4 becomes 36 kg ÷ 40 kg = 0.9 times, and the fifth region R5 becomes 32.4 ÷ 40 kg = 0.81 times (see step S6 in Figure 9). Each of these ratios is multiplied by the standard fertilizer application amount of 32.4 kg to correct the fertilizer application amounts from the first region R1 to the fifth region R5 (see step S7 in Figure 9). In other words, the fertilizer application rate for the first region R1 is 32.4 × 1.21 = 39.2 kg / 10a, for the second region R2 it is 32.4 × 1.1 = 35.6 kg / 10a, for the third region R3 it is 32.4 × 1 = 32.4 kg / 10a, for the fourth region R4 it is 32.4 × 0.9 = 29.1 kg / 10a, and for the fifth region R5 it is 32.4 × 0.81 = 26.2 kg / 10a. The fertilizer application rates obtained in this way are replaced with the fertilizer application rates for each region of the first fertilization maps 20 to 23 created for each field (see step S8 in Figure 9). The control unit 87 stores the replaced fertilizer application rates for the first fertilization maps 20 to 23 in the storage unit (not shown). The standard fertilizer application rate refers to the minimum amount of fertilizer that must be applied. In this embodiment, it is set to the value of the fifth region R5, which has the lowest fertilizer application rate among the five regions R1 to R5 in the two fields, but it may be set to any other arbitrary value. In this embodiment, a correction is made to reduce the fertilizer application rates in the created first fertilizer application maps 20 to 23, but in some cases, a correction may be made to increase the fertilizer application rates in the created first fertilizer application maps 20 to 23 by looking at the difference between the fertilizer application rates in the first fertilizer application maps 20, 21, 22, and 23 and the fertilizer application rates in the four fields in the second fertilizer application map 24.

[0084] The control unit 87 then replaces the fertilizer application amounts corrected based on the fertilizer application amounts in the second fertilizer map 24 with the fertilizer application amounts in the first fertilizer maps 20 to 23 for each field A to D. For example, the fertilizer application amounts in the five regions R1 to R5 of field D in the created first fertilizer map 23 are replaced. In other words, the first region R1 in the first fertilizer map 23 is replaced with a fertilizer application amount of 39.2 kg / 10a, the second region R2 with a fertilizer application amount of 35.6 kg / 10a, the third region R3 with a fertilizer application amount of 32.4 kg / 10a, the fourth region R4 with a fertilizer application amount of 29.1 kg / 10a, and the fifth region R5 with a fertilizer application amount of 26.2 kg / 10a. The control unit 87 then replaces the fertilizer application amounts in the created first spray maps 20, 21, 22, and 23 with the corrected fertilizer application amounts and stores them in the storage unit (not shown). When fertilizing each field A to D, the fertilizer application is carried out based on the replaced fertilizer application amounts and the machine's position information.

[0085] <Control in case of anomalies where the scatter map is unavailable> Furthermore, if the control unit 87 is unable to acquire its own position due to poor reception by the positioning device (receiving antenna 130) or if variable spraying based on the spray map becomes impossible due to a display malfunction of the spray map (first spray maps 20, 21, 22, 23) during fertilizer application, it controls the machine to continue fertilizing at the maximum amount of fertilizer applied before the malfunction. This prevents insufficient fertilizer application even when a malfunction occurs. The aforementioned malfunction also includes cases where the communication connection (Bluetooth communication, etc.) with the communication device (tablet / monitor) that transmits the information after reading the information from the spray map is interrupted. The control unit 87 stores five levels of fertilizer setting values, from the minimum value (setting value 1) to the maximum value (setting value 5). As described above, if variable spraying based on the spray map becomes impossible in field D, the control unit 87 displays the "Variable Fertilizer Setting Screen" on the display unit 61A of the monitor 61, as shown in Figure 12(a). The display unit 61A shows the basic fertilizer application rate of 32.0 kg / 10a, specific gravity (set value) of 0.93, and trial dispensing amount, and the set values ​​for each can be changed. Below the display of these set values, the fertilizer application rate set to setting value 1 is 32 kg / 10a, setting value 2 is 34 kg / 10a, setting value 3 is 37 kg / 10a, setting value 4 is 40 kg / 10a, and setting value 5 is 45 kg / 10a. As a fertilizer setting value to be used in the event of the aforementioned malfunction, the maximum fertilizer application rate of 45 kg / 10a, the same as setting value 5, is displayed as setting value 0. Then, by tapping the fertilizer setting section 61H on the screen, the screen switches to the fertilizer setting screen shown in Figure 12(b). If the operator is satisfied with the maximum fertilizer application rate of 45 kg / 10a, they press the confirm button 61K. To change the fertilizer application rate from the maximum rate of 45 kg / 10a, press the down switch 61D to change to the desired rate, and then press the confirm button 61K to confirm. If the application rate is lower than the desired rate due to an operational error, etc., press the up button 61U to return to the desired rate. Figure 13(a) is the same as Figure 12(a), except that the fertilizer application rate for setting value 0 is set to the intermediate value of 37 kg / 10a.Then, by tapping the fertilization setting section 61H on the screen shown in Figure 13(a), the screen switches to the fertilization setting screen shown in Figure 13(b). If the operator is satisfied with the intermediate fertilization rate (average fertilization rate) of 37 kg / 10a, they press the confirm button 61K. If the operator wishes to change the fertilization rate to something other than the intermediate fertilization rate (average fertilization rate) of 37 / 10a, they press the up button 61U or down button 61D to change to the desired fertilization rate, and then press the confirm button 61K to confirm. After the fertilization rate has been determined, rice planting in field D is resumed.

[0086] <Sub-radiator> By installing a sub-radiator in addition to the main radiator mounted on work vehicle 1, the cooling effect of the coolant can be enhanced, and overheating can be prevented even if the main radiator becomes clogged.

[0087] <Fertilizer hopper> If the fertilizer hopper is constructed with a first layer made of a material with low thermal conductivity on the outside, a second layer made of a material with high thermal conductivity on the inside, and a heating element placed between the first and second layers, it will not only be effective against moisture inside the hopper (convection), but the fertilizer that comes into direct contact with it will be heated and dried by the most thermally efficient heat conduction. This makes it less likely for the fertilizer to become clogged. The power for the heating element may be supplied directly from a battery, and a relay may be provided in the circuit, along with a key switch that supplies or cuts off power to the coil that operates the relay, so that the operation of the heating element can be controlled by turning the key switch ON or OFF.

[0088] <Dynamo> Alternatively, a bracket for mounting a dynamo can be attached to the fertilizer application frame, allowing the dynamo to generate electricity using the rotation of the rear wheel. Or, a bracket for mounting a dynamo can be attached to the rear case, allowing the dynamo to generate electricity using the rotation of the rear wheel shaft.

[0089] <Fertilizer application> Alternatively, a bellows tube equipped with an electric heating element can be installed inside the fertilizer hose that guides the fertilizer dispensed from the fertilizer applicator to the field, allowing only the inside of the hose to be heated while maintaining the hose's flexibility. Furthermore, by providing numerous small holes in the grooves of the fertilizer dispensing roll on the fertilizer applicator and releasing warm air from these holes, the adhesion of fertilizer to the grooves of the dispensing roll can be reduced.

[0090] <Seedling tank> The system may be configured to automatically stop when the seedling tank, which stores the seedling mat, moves from one end to the center. Specifically, automatic control is performed using the number of lateral movements of the seedling mat and the number of pulses detected from the rotation axis of the seedling feeding shaft. In other words, the number of pulses detected from the rotation axis of the seedling feeding shaft, which is output when the seedling tank is moved from one end to the center, is set for each lateral movement, and when the set number of pulses is reached, the drive of the seedling planting unit that plants the seedlings is stopped (for example, the planting clutch is disengaged). Since the pulse count starts from the time the control to move the seedling tank from one end to the center begins, labor is saved. The operation can be simplified by performing the control to move the seedling tank from one end to the center after the control to move the seedling tank to either the left or right end. In addition, a switch can be provided on the rod of the seedling tank lateral movement shifter, and the set number of lateral movements can be detected by changing the switch pressed depending on the position of the seedling tank lateral movement shifter. Furthermore, by providing a gear on the seedling feeding shaft and a sensor on the frame of the seedling planting unit to detect the rotation speed of this gear, it becomes possible to detect the amount of movement of the seedling tank in conjunction with the detected number of lateral movements. When controlling the movement of the seedling tank from one end to the center, the detection of the so-called "tight-position switch," which moves the seedling tank to either the left or right end, is disabled. If there is no detection unit to detect lateral movement, the control to move the seedling tank from the end to the center can be performed by setting the number of pulses to 12, which is half of the 24 number of lateral movements. This reduces the number of detection units (e.g., switches), leading to cost reduction.

[0091] The embodiments of the present invention have been described above. The present invention is not limited to the embodiments described above. It goes without saying that modifications can be made as appropriate within the scope of the technical idea.

[0092] In the above embodiment, the application of fertilizer was shown, but other chemicals such as insecticides, antibacterial agents, herbicides, or soil conditioners such as lime may also be applied.

[0094] Furthermore, in the above embodiment, two fields were selected in the second fertilization map, and the fertilization amount (amount applied) in the first fertilization map was corrected based on the fertilization amount (amount applied) in the two selected fields. However, one or any number of fields (three or more) may be selected in the second fertilization map, and the fertilization amount (amount applied) in the first fertilization map may be corrected based on the fertilization amount (amount applied) in the one or three or more selected fields. By selecting two or more fields, the accuracy of the corrected fertilization amount (amount applied) can be improved.

[0095] Furthermore, in the above embodiment, the smallest application rate (fertilizer application rate) in the two selected fields was used as the standard application rate (standard fertilizer application rate). However, the largest application rate (fertilizer application rate) may also be used as the standard application rate (standard fertilizer application rate), or the most frequent application rate (fertilizer application rate) may be used as the standard application rate (standard fertilizer application rate). Alternatively, the average value obtained by dividing the total application rate (total fertilizer application rate) in two or more selected fields by the total area of ​​the two or more selected fields may be used as the standard application rate (standard fertilizer application rate). Furthermore, the application rate (fertilizer application rate) in the area with the largest area across all regions of the two or more selected fields may also be used as the standard application rate (standard fertilizer application rate).

[0096] Furthermore, although a rice transplanter was shown as the work vehicle in the above embodiment, a tractor or a dedicated fertilizer spreader that is mobile and only performs fertilization may also be used. [Explanation of Symbols]

[0097] 1...Work vehicle, 2...Vehicle body, 3...Main frame, 4...Power transmission mechanism, 5...Lifting link device, 6...Rear frame, 7...Engine, 8...Front wheel, 9...Rear wheel, 10...Link base frame, 11...Upper and lower link arm, 12...Lifting hydraulic cylinder, 13...Front wheel final case, 14...Rear wheel transmission shaft, 15...Correction means, 16...Finger lever sensor, 17...Swivel control switch, 18...Center mascot, 19...Planting on / off switch, 20, 21, 22, 23...First fertilization map, 24...Second fertilization map, 25...Hydrogenic continuously variable transmission Machine, 26...Fertilizer applicator, 27...Planting clutch motor, 28...Marker switch, 29...Rear wheel rotation speed sensor, 30...Transmission case, 31...Front axle, 33...Float sensor, 34...Marker motor, 35...Main shift lever, 36...Main shift lever sensor, 37...Tilt detection sensor, 38...Center float, 39...Side float, 40...Line drawing marker, 41...Line drawing body, 42...Marker rod, 43...Steering mechanism, 44...Remote controller, 44a...Display unit, 45...Steering sensor, 47...Front cover, 48... 49...cockpit, 50...control unit, 51...antenna cover, 52...rear wheel gear case, 54...remote control antenna, 55...operating unit, 56...steering wheel, 57...steering motor, 58...pitman sensor, 60...floor step, 61...monitor, 61A...display unit, 63...seedling planting unit, 64...planting device, 65...stand, 66...fertilizer amount adjustment motor, 67...drive shaft, 69...planting tool, 70...navigation ECU, 71...steering ECU, 74...auxiliary seedling frame, 77...frame, 79...straight assist lever, 80...direction sensor S, 81...Straight assist lever sensor, 82...Axle, 83...Steering shaft, 85...Upper link arm, 86...Lower link arm, 87...Control unit, 88...Electro-hydraulic valve, 89...Link sensor, 96...Engine speed sensor, 97...Throttle motor, 103...Solenoid valve, 108...Power steering, 110...Seat switch, 130...Positioning device (receiving antenna), 150...HST servo motor, 441...Round F switch, 442...Round F switch, A, B, C, D...Field, H...End (field), R1~R5...Area

Claims

1. A work vehicle comprising a spraying device and a positioning device for acquiring the vehicle's own position, and a control unit capable of variable spraying based on a spraying map that links the vehicle's own position information acquired by the positioning device with the amount of sprayed, The aforementioned spraying map comprises a plurality of first spraying maps created for each of the plurality of fields so as to show the amount to be sprayed in each field, and a second spraying map created so as to show the amount to be sprayed over the entire area of ​​the plurality of fields. Each of the fields in the first spraying map and each of the fields in the second spraying map is divided into multiple areas with different spraying rates. The control unit determines a standard spray amount and a reference value from the spray amounts of the plurality of areas in the second spray map, calculates the ratio for each area in the second spray map from the spray amount for each area and the reference value, corrects the spray amount by multiplying the standard spray amount by the ratio for each area, replaces the spray amount for each area in the first spray map with the corrected spray amount, and performs variable spraying based on the replaced spray amount.

2. The work vehicle according to Claim 1, characterized in that the standard spraying amount is the spraying amount of the area with the smallest spraying amount, and the standard value is the spraying amount that is the median of the spraying amounts of the plurality of areas with different spraying amounts.

3. The work vehicle according to claim 1, further comprising a display unit capable of displaying the plurality of first and second scatter maps, wherein the control unit causes the plurality of first and second scatter maps to be displayed on the display unit simultaneously.

4. The work vehicle according to claim 1, characterized in that the control unit acquires outline information for each of the multiple fields based on the position information of each of the multiple fields in the second spraying map, and identifies fields with a large area and fields with a small area by comparing the acquired outline information of the multiple fields.

5. The work vehicle according to claim 1 or 2, characterized in that, if the control unit cannot obtain its own position from the positioning device during spraying, or if variable spraying using the spray map becomes impossible due to an abnormality, it controls the vehicle to continue spraying at the maximum amount of spraying that was being sprayed before the abnormality occurred.

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