JP7501501B2 - Seedling transplanter - Google Patents

Description

The present invention relates to a seedling transplanter.

It is known that in a conventional seedling transplanter that performs the task of planting seedlings while autonomously traveling based on predetermined course information, the task proceeds by repeating a straight line process in which the seedlings are planted while traveling in a straight line, and a turning process in which the straight line process is switched to the next straight line process (see, for example, Patent Document 1).

JP 2020-31596 A

However, in a conventional seedling transplanter such as the one described above, if the machine body is misaligned left or right during the straight-line process, the machine body will continue to work while remaining misaligned left or right, and the spacing between the seedling planting rows will not be kept constant, resulting in poor seedling planting performance. As such, conventional seedling transplanters have room for improvement in terms of improving seedling planting performance.

The present invention has been made in consideration of the above, and aims to provide an autonomous seedling transplanter that can improve seedling planting performance.

In order to solve the above-mentioned problems and achieve the object, the seedling transplanter (1) according to the present invention is capable of autonomous travel and performs seedling planting work while autonomously traveling within a farm field (F). It is equipped with a control unit (100) that causes the seedling transplanter (1) to perform a straight-line process of planting seedlings while traveling in a straight line based on predetermined course information (R), a turning process for transitioning from the straight-line process to the next straight-line process, and a headland process of planting seedlings in a headland area of the farm field (F), and the control unit (100) is characterized in that the course (TR) of the seedling transplanter 1 can be adjusted in the left-right direction during the seedling planting process.

The seedling transplanter of the present invention can improve the seedling planting performance in an autonomously moving seedling transplanter.

FIG. 1 is a schematic side view showing an example of a seedling transplanter according to an embodiment. FIG. 2 is a block diagram showing an example of a control system centered around a control unit. FIG. 3 is an explanatory diagram of autonomous traveling in a farm field. FIG. 4 is an explanatory diagram of the arrangement of the course adjustment operation tools (part 1). FIG. 5 is an explanatory diagram of the operation of the course adjustment operation tool. FIG. 6 is an explanatory diagram of course adjustment by operating the course adjustment operating tool. FIG. 7 is an explanatory diagram of the arrangement of the course adjustment operation tool (part 2). FIG. 8 is an explanatory diagram of remote control (part 1) using a remote control tool. FIG. 9 is an explanatory diagram of remote control (part 2) using a remote control tool. FIG. 10 is an explanatory diagram of a relay antenna. FIG. 11 is a flowchart showing a process (part 1) of control for preventing a worker on board the machine from falling. FIG. 12 is a flowchart showing a process (part 2) of control for preventing a worker on board the machine from falling. FIG. 13 is an explanatory diagram (part 1) of an engine downsizing structure. FIG. 14 is an explanatory diagram (part 2) of the engine downsizing structure. FIG. 15 is an explanatory diagram of fertilizer clogging in the dispensing device. FIG. 16 is a flowchart showing the fertilizer clogging removal control process (part 1). FIG. 17 is a flowchart showing the fertilizer clogging removal control process (part 2). FIG. 18 is a flowchart showing the fertilizer clogging removal control process (part 3). FIG. 19 is an explanatory diagram (part 1) of the front sensor cover. FIG. 20 is an explanatory diagram (part 2) of the front sensor cover.

The following describes in detail the embodiments of the seedling transplanter disclosed in the present application with reference to the attached drawings. Note that the present invention is not limited to the embodiments described below.

<Overall configuration of seedling transplanter>
First, the overall configuration of a seedling transplanter 1 according to an embodiment will be described with reference to Fig. 1. Fig. 1 is a schematic side view showing an example of a seedling transplanter 1 according to an embodiment.

Note that Figure 1 shows a three-dimensional Cartesian coordinate system including the Z axis, with the positive direction being vertically upward (upward). For ease of explanation, the positive direction of the X axis is defined as the left, the negative direction of the X axis as the right, the positive direction of the Y axis as the front, and the negative direction of the Y axis as the rear, with the X axis direction being referred to as the left-right direction, the Y axis direction being referred to as the front-back direction, and the Z axis direction being referred to as the up-down direction.

In the following, the seedling transplanter 1 or the traveling vehicle body 2 described below may be referred to as the "machine body."

As shown in FIG. 1, the seedling transplanter 1 includes a traveling vehicle body 2 capable of traveling within a field F (see FIG. 3), and a seedling planting unit 3 that plants seedlings on the soil surface of the field F. The seedling transplanter 1 is a riding seedling transplanter operated by an operator (also called an operator), but is also a seedling transplanter that can perform automatic seedling planting work while traveling autonomously along a preset planned traveling route R (see FIG. 3).

The traveling vehicle body 2 has a pair of left and right front wheels 11 and a pair of left and right rear wheels 12. In the traveling vehicle body 2, the pair of left and right front wheels 11 are steered wheels. In addition, in the traveling vehicle body 2, the pair of left and right rear wheels 12 are driven wheels. Note that, for example, in the forced four-wheel drive mode described below, the pair of left and right front wheels 11 and the pair of left and right rear wheels 12 are driven wheels.

In addition, at the front of the main frame 13, which forms the body skeleton of the traveling vehicle body 2, there is provided a transmission case 14 that transmits driving force to the seedling planting section 3 (described later) and other parts, and a hydraulic continuously variable transmission (not shown) that outputs the driving force supplied from the engine E, i.e., the rotation of the engine E, to the transmission case 14.

The continuously variable transmission is a hydrostatic type continuously variable transmission called HST (Hydro Static Transmission). In the following, the continuously variable transmission will be referred to as "HST."

A sub-transmission mechanism (not shown) is provided inside the transmission case 14 to switch driving modes when driving on the road, planting seedlings, etc. In the traveling vehicle body 2, front wheel final cases 15 are provided on the left and right sides of the transmission case 14, and the front wheels 11 are attached to left and right front axles that protrude outward from support parts that can change the steering direction of the left and right front wheel final cases 15, respectively.

In addition, rear wheel gear cases 16 are provided on the left and right sides of the rear frame, which extends in the left-right direction, at the rear of the main frame 13, and rear wheels 12 are attached to the left and right rear axles that protrude outward from the rear wheel gear cases 16, respectively.

Also, left and right link support frames 18 that support lift links 17 (described later) are provided extending upward from the upper part of the rear frame. Left and right upper links 19 and left and right lower link arms 20 are provided between the left and right link support frames 18. Hydraulically operated lift cylinders 21 are provided between the left and right upper links 19 and left and right lower link arms 20 in the left-right direction.

The left and right upper links 19 and the left and right lower link arms 20 form the lifting link 17, which is a parallel link mechanism. The left and right upper links 19, the left and right lower link arms 20, and the lifting cylinder 21 each have one end connected to the traveling vehicle body 2, and the other end connected to the seedling planting section 3.

An engine E is mounted on the main frame 13. The rotational power of the engine E is transmitted to the transmission case 14 via a belt transmission device (not shown) and the HST. The rotational power transmitted to the transmission case 14 is changed in speed by the sub-transmission mechanism in the transmission case 14, and then separated into driving power and power to be taken out from the outside.

The rotational power of the engine E is also transmitted to a hydraulic pump (not shown). The hydraulic pressure generated by the hydraulic pump is supplied to the HST, the power steering mechanism 23 of the steering wheel 22 (see FIG. 2), the lift cylinder 21, etc.

The externally extracted power extracted from the rotational power transmitted to the transmission case 14 is transmitted to a planting clutch 24 (see Figure 2) provided at the rear of the traveling body 2, and is transmitted from the planting clutch 24 to the seedling planting section 3 via a planting transmission shaft (not shown).

Meanwhile, left and right drive shafts (not shown) are provided at the rear of the transmission case 14. Rotational power from the engine E is transmitted to the left and right rear wheel gear cases 16 via the transmission case 14 and the drive shafts.

In addition, a side clutch 25 (see FIG. 2) that switches power transmission to the left and right drive shafts is located upstream of the left and right drive shafts in the power transmission direction. As shown in FIG. 1, for example, a side clutch pedal (not shown) that switches the left and right side clutches 25 on and off is provided at the lower front part of the cockpit 26 and on the left and right sides.

When the vehicle is turned around by depressing the side clutch pedal on the inside of the turn to disengage the side clutch 25 and then operating the steering wheel 22, the drive rotation of the rear wheel 12 on the inside of the turn can be completely cut off.

A bonnet 28 that houses the engine E is provided in front of the floor step 27 of the traveling vehicle body 2. A control panel 29 is provided at the rear of the bonnet 28. The control panel 29 is provided with a meter panel, a display unit that displays various information, and various operating tools such as switches. In addition, a steering wheel 22 is provided at the rear of the bonnet 28.

The bonnet 28 is also provided with a steering handle 22 for steering the traveling vehicle body 2, a main speed change lever 30 for operating the HST and the seedling planting section 3, and a sub-speed change lever 31 for operating the sub-speed change mechanism (see Figure 2).

In addition, an openable front cover 28a is provided at the front of the bonnet 28. Inside the front cover 28a, a fuel tank, a battery, and an interlocking mechanism that rotates the left and right front wheels 11 and the lower sides of the left and right front wheel final cases 15 in response to the steering of the steering wheel 22 are provided.

A fertilizer applicator 40, described below, is provided behind the driver's seat 26 and at the rear of the main frame 13. The driving force of the fertilizer applicator 40 is transmitted by a fertilizer transmission mechanism that is provided facing the fertilizer applicator 40 from one of the left and right sides of the left and right rear wheel gear cases 16.

The above-mentioned floor steps 27 are formed on the left and right sides of the lower part of the bonnet 28. The floor steps 27 are approximately horizontal and partially lattice-shaped, so that even if mud on the shoes of an operator (worker) walking on the floor steps 27 falls onto the floor steps 27, the fallen mud will fall into the field F.

In addition, spare seedling frames 34 are provided at the front and on the left and right sides of the traveling vehicle body 2, with multiple spare seedling placement platforms 33 arranged at intervals in the vertical direction on seedling frame supports 32. The spare seedling frames 34 can hold work materials such as seedlings (seedling mats) and fertilizer bags to be replenished in the seedling planting section 3.

A seedling tank 35, which carries seedlings (seedling mats) to be planted in the field, is connected to the rear end of the lifting link 17 along with a sliding mechanism that slides it left and right. The seedling tank 35 is provided with a fence that divides the top surface of the seedling tank 35 (the surface on which the seedling mats are placed) into multiple sections left and right. A planting device 36 is provided below the seedling tank 35, which scrapes off seedlings from the loaded seedling mats and plants them in the field F.

The planting device 36 simultaneously plants the same number of seedlings as the number of planting rows separated by the fence described above. The planting device 36 is equipped with a planting transmission case 37, a planting rod 38, and a planting rotary 39. In the planting device 36, the planting transmission case 37 is provided below the seedling tank 35 with a gap therebetween, and the planting rotary 39 for rotating the planting rod 38 is provided on the left and right sides of the planting transmission case 37. In the planting device 36, the planting rod 38 picks up seedlings as it rotates, and plants the picked seedlings in the field F.

The fertilizer application device 40 includes a fertilizer application hopper 41, a dispensing device 42, a duct 43, a fertilizer application hose (not shown), and a blower (not shown). The fertilizer application hopper 41 stores fertilizer. The fertilizer application hopper 41 is divided into the same number of sections as the number of working rows in the seedling planting section 3. Note that the fertilizer application hopper 41 may have a so-called side fertilization structure in which half of the total rows (for example, four rows in the case of eight rows) are arranged on each side, since the convenience of adding fertilizer and attaching and detaching the fertilizer may be reduced if the fertilizer application hopper 41 is long in the left-right direction.

The payout devices 42 are provided at the bottom of the fertilizer hopper 41, one row at a time, and supply a set amount of fertilizer. The duct 43 is provided below the payout devices 42, and allows the conveying air that moves the fertilizer to pass through. The fertilizer hose is provided below the payout devices 42, and guides the fertilizer to the vicinity of the seedling planting position in the seedling planting section 3. The blower is provided at one end of the duct 43, and generates conveying air using the driving force of an electric blower motor (not shown).

A float 44 is provided below the seedling planting section 3. The float 44 has a center float 44a in the middle and left and right side floats 44b. The center float 44a and the left and right side floats 44b contact the soil surface of the field F and slide on the soil surface as the traveling vehicle body 2 moves forward.

The seedling planting section 3 is provided with a soil leveling rotor 45 that is located forward of the float 44 and that levels out unevenness in the soil surface. The soil leveling rotor 45 is located forward of the center float 44a and in front of the left and right side floats 44b. The seedling planting section 3 plants seedlings in the soil surface leveled by the soil leveling rotor 45. Driving force is transmitted to the soil leveling rotor 45 via a rotor transmission shaft (not shown).

Line drawing markers (not shown) are provided on the left and right sides of the seedling planting section 3, one of which comes into contact with the soil surface of the field F to form a groove (guide line) that serves as a guide for traveling in the next work row (next process). When one of the left and right line drawing markers descends and comes into contact with the ground, the other rises. When the seedling planting section 3 is raised while the machine is turning, both left and right line drawing markers rise, and when the seedling planting section 3 descends after the machine has turned, one of the left and right line drawing markers rises and the other descends (comes into contact with the ground).

In addition, a center mascot 46 is erected so as to extend vertically in the center of the traveling vehicle body 2 in the left-right direction and in front of the bonnet 28. By aligning the center mascot 46 with the guide lines formed on the soil surface of the field F by the left and right line markers, it becomes possible to travel in accordance with the work position of the previous work row, improving work accuracy and preventing non-working.

Depending on the soil quality of the field F, the guide lines formed by the left and right line-drawing markers may quickly become buried, causing the guide for going straight to disappear. In such cases, it is a good idea to use left and right side markers (not shown) that are placed forward of the left and right line-drawing markers. In other words, by moving the left and right side markers outward and positioning the side markers above the planted seedlings, planting work can be performed in accordance with the planting of the seedlings in the previous work row.

As shown in FIG. 1, the seedling transplanter 1 is also equipped with a position information acquisition device 50. The position information acquisition device 50 acquires the current position (or orientation) of the seedling transplanter 1. The position information acquisition device 50 acquires the current position (or orientation) of the seedling transplanter 1 by using a satellite positioning system such as the Global Positioning System (GPS) or the Global Navigation Satellite System (GNSS). Note that the position information acquisition device 50 may be composed of multiple devices.

The position information acquisition device 50 receives positioning information, for example, from a satellite positioning system, and creates current position information (or orientation information) of the traveling vehicle body 2 based on the received positioning information. The position information acquisition device 50 is, for example, supported by an antenna frame 51 and disposed above the traveling vehicle body 2.

The straight-line control program and the turning control program, which are created based on the position information from the position information acquisition device 50, are stored in different locations. The straight-line control program is stored, for example, in a straight-line control ECU (Electronic Control Unit) in the position information acquisition device 50, and the turning control program is stored, for example, in a turning control ECU housed in the bonnet 28. The straight-line control ECU and the turning control ECU are included in the control unit 100 (see FIG. 2), which will be described later. Note that the straight-line control ECU and the turning control ECU may be the same ECU.

<Seedling transplanter control system>
Next, the control system of the seedling transplanter 1 (see FIG. 1) will be described with reference to Fig. 2. Fig. 2 is a block diagram showing an example of a control system centered around a control unit 100. The seedling transplanter 1 is capable of controlling each part by electronic control, and is equipped with a control unit 100 that controls each part.

The control unit 100 has, for example, a processing unit having a CPU (Central Processing Unit) and the like, a storage unit such as a ROM (Read Only Memory) and a RAM (Random Access Memory), and an input/output unit, which are interconnected to enable signals to be exchanged between them. The storage unit stores computer programs and the like that control the seedling transplanter 1. The control unit 100 performs each function by reading out computer programs and the like stored in the storage unit and the like.

The control unit 100 is connected to actuators such as a throttle motor 60, hydraulic control valves 61 and 62, a planting clutch actuation solenoid 63, a side clutch actuation solenoid 64, an HST motor 65, a steering motor 66, a line drawing marker lifting motor 67, and a differential lock switching motor 68.

The throttle motor 60 increases or decreases the rotation speed of the output shaft of the engine E by operating a throttle that adjusts the amount of air intake into the engine E. The hydraulic control valve 61 controls the extension and retraction of the lift cylinder 21. The hydraulic control valve 62 controls the power steering mechanism 23. The planting clutch actuation solenoid 63 actuates the planting clutch 24.

The side clutch actuation solenoid 64 actuates the side clutch 25, which switches the power transmission state to the rear wheels 12 (see FIG. 1). The HST motor 65 changes the rotation angle of the HST trunnion, thereby changing the inclination angle of the HST swash plate. The steering motor 66 steers and drives the front wheels 11 (see FIG. 1), which are the steered wheels. The steering motor 66 is a motor that drives the steering wheel 22, which adjusts the steering amount (also called the steering angle or turning angle) of the front wheels 11 when automatic turning control is performed. The line drawing marker lifting motor 67 lifts and lowers the line drawing marker.

The differential lock switching motor 68 is a motor that switches between the operation and deactivation of a differential lock mechanism (hereinafter referred to as the diff-lock mechanism) 69, which rotates the left and right running wheels (for example, the front wheels 11) at the same rotational speed. When the diff-lock mechanism 69 is engaged, the vehicle can be forcibly put into four-wheel drive (forced four-wheel drive mode), and the left and right running wheels rotate at the same rotational speed. The diff-lock pedal (not shown) for operating the diff-lock mechanism 69 is provided with a rotating part to prevent the pedal from sagging and to ensure stable operation.

The control unit 100 is also connected to a rotation speed sensor 70, a steering amount sensor 71, an inclination sensor 72, and the like. Two rotation speed sensors 70 are provided corresponding to the left and right rear wheels 12, and detect the rotation speeds of the left and right rear wheels 12, respectively. The rotation speed sensors 70 may also detect the rotation speeds of the left and right front wheels 11.

The steering amount sensor 71 detects the steering amount of the steering wheel 22, i.e., the steering amount (steering angle, turning angle) of the front wheels 11. The steering amount sensor 71 is mounted, for example, on a shaft that connects to a pitman arm. The steering amount is detected in both the left and right directions, with the value when the steering wheel 22 is in a preset straight ahead position being used as a reference value.

More than one steering amount sensor 71 may be provided.Moreover, the steering amount sensor 71 may be provided at more than one location. By detecting the steering amount of the front wheels 11 using more than one steering amount sensor 71, the detection accuracy can be improved.The tilt sensor 72 detects the tilt angle, which is the tilt of the seedling transplanter 1.

In addition, signals are input to the control unit 100 as operation signals from the main speed change lever 30, the sub-speed change lever 31, the mode change switch 73, the seedling planting section lift switch 74, the automatic turning change switch 75, the line drawing marker automatic lift switch 76, etc. The mode change switch 73 is a switch that switches whether or not to execute autonomous driving.

The seedling planting section lift switch 74 is a switch that switches between raising and lowering the seedling planting section 3. The seedling planting section lift switch 74 can be changed between the "up" and "down" positions. When the seedling planting section lift switch 74 is in the "up" position, the seedling planting section 3 rises to a predetermined non-working position and the planting device 36 (see Figure 1) stops, resulting in a non-working state (seedling planting section 3 is off). When the seedling planting section lift switch 74 is in the "down" position, the seedling planting section 3 descends to a predetermined working position and the planting device 36 operates, resulting in a working state (seedling planting section 3 is on). In other words, the seedling planting section lift switch 74 is a switch that can detect the working state of the seedling planting section 3.

The automatic turning changeover switch 75 is a switch that changes whether automatic turning is enabled or disabled when the seedling transplanter 1 is manually operated, for example. When the automatic turning changeover switch 75 is "ON", automatic turning is enabled. When the automatic turning changeover switch 75 is "OFF", automatic turning is disabled.

The automatic line drawing marker raising/lowering switch 76 is a switch that switches whether or not the line drawing marker is automatically raised/lowered in conjunction with the steering amount of the steering wheel 22 (i.e., the steering amount of the front wheels 11). When the automatic line drawing marker raising/lowering switch 76 is "ON", control is executed to automatically raise/lower the line drawing marker in conjunction with the steering amount. On the other hand, when the automatic line drawing marker raising/lowering switch 76 is "OFF", control is not executed to automatically raise/lower the line drawing marker in conjunction with the steering amount.

In addition, a direction sensor (not shown) and the like are connected to the control unit 100. The direction sensor detects, for example, the absolute direction angle of the traveling direction of the seedling transplanter 1 (for example, "north" is 0° (360°), "east" is 90°, "south" is 180°, and "west" is 270°). The direction sensor detects the absolute direction angle at regular intervals and transmits the detected absolute direction angle to the control unit 100.

Here, the control unit 100 causes the seedling transplanter 1 (traveling body 2 and seedling planting unit 3) to execute the straight-line process, turning process, and headland process, which will be described later, based on predetermined course information that has been set in advance. The control unit 100 is also capable of adjusting the course TR (see FIG. 6) of the seedling transplanter 1 in the left-right direction while the seedling transplanter 1 is executing a process of planting seedlings (for example, the straight-line process). In this case, a signal is input to the control unit 100 as an operation signal from the course adjustment operating device 80, which will be described later.

The course adjustment operation tool 80 is operated when the course TR of the autonomously traveling seedling transplanter 1 deviates left or right, for example, to move the seedling transplanter 1 a specified amount to the left or right of the current traveling direction of the course TR. The course adjustment operation tool 80 is provided around the steering handle 22, for example, on the operation panel 29 (see FIG. 1) or an operation tool (for example, the main shift lever 30) provided on the operation panel 29.

When the seedling transplanter 1 is traveling autonomously with the operator (worker) seated in the operator's seat 26 (see Figure 1), the course adjustment operating device 80 can be operated by the operator (worker) if the course TR of the seedling transplanter 1 deviates left or right, allowing the seedling transplanter 1 to move to the left or right relative to the traveling direction of the current course TR, as described above. The course adjustment operating device 80 will be described later using Figures 4 to 7.

The control unit 100 is also connected to a remote control device 90 so that they can communicate with each other, and various signals and information are input from the remote control device 90. Note that the control unit 100 receives various signals and information from the remote control device 90, for example, via a receiver (not shown) provided on the traveling vehicle body 2 (see FIG. 1). The remote control device 90 is operated by an operator when a remote operation mode that accepts remote operation of the seedling transplanter 1 is executed. In the remote operation mode, the operator operates the remote control device 90, allowing remote operation of the seedling transplanter 1.

The remote control device 90 transmits a control signal corresponding to the operation of the operator to the control unit 100. The remote control device 90 is communicatively connected to the control unit 100 by short-range wireless communication such as Wi-fi (registered trademark) or Bluetooth (registered trademark). It is preferable that the remote control device 90 is communicatively connected to the control unit 100 by Bluetooth (registered trademark). Note that the remote control device 90 may be communicatively connected via a communication network or the like in addition to (or instead of) short-range wireless communication.

The remote control device 90 is a mobile terminal device having a display unit 91 such as a liquid crystal screen. The remote control device 90 is preferably a tablet terminal device such as a smartphone. The remote control device 90 may be a remote control device. In the case of a remote control device, the remote control device 90 is a remote control device (a remote control with liquid crystal) having a display unit 91 such as a liquid crystal screen. The remote control device 90 may communicate directly with the seedling transplanter 1, or may communicate with the seedling transplanter 1 via the relay antenna 150. The remote control device 90 may be a single-function remote control provided with only an emergency stop switch, which allows immediate operation to stop the seedling transplanter 1 in an emergency.

<Autonomous Driving>
Next, referring to Fig. 3, the autonomous travel of the seedling transplanter 1 in the field F will be described. Fig. 3 is an explanatory diagram of the autonomous travel in the field F. Fig. 3 also shows a schematic diagram of the seedling transplanter 1 autonomously traveling in the field F.

The control unit 100 (see Figure 2) has an autonomous driving mode in which the steering handle 22 (see Figures 1 and 2) is controlled while feeding back the steering amount of the front wheels 11 (see Figure 1) to cause the seedling transplanter 1 to drive autonomously.

In the autonomous driving mode, the control unit 100 controls the steering wheel 22 to control the traveling direction of the seedling transplanter 1 as described above. In the autonomous driving mode, the control unit 100 controls the rotation speed of the engine E (see Figures 1 and 2) to control the vehicle traveling speed (vehicle speed). In the autonomous driving mode, the control unit 100 may also control the vehicle speed by performing a brake operation.

As shown in FIG. 3, in the autonomous driving mode, the seedling transplanter 1 automatically performs seedling planting work by, for example, repeatedly moving straight and turning along the planned driving route R set in the field F as course information. As described above, the control unit 100 acquires information on the current position (self-position P) and turning position of the seedling transplanter 1 using the position information acquisition device 50 (see FIG. 1) provided on the top of the machine body.

When the control unit 100 causes the seedling transplanter 1 to travel autonomously, it creates a planned travel route R (R1, R2) as route information that specifies appropriate turning positions, etc., based on information including, for example, the working width of the seedling planting unit 3 (see Figure 1) and the shape and area of the field F.

In this case, the seedling transplanter 1 performs seedling planting work by repeatedly moving straight and turning along a planned travel route R from a pre-set work start point P _S to a work end point P _E , for example, within a set work area in a farm field F.

The planned travel path R1 has a straight path R _S and a turning path R _T. On the straight path R _S , the control unit 100 causes the seedling transplanter 1 to execute a straight movement process in which the seedling transplanter 1 moves straight while planting seedlings. On the turning path R _T , the control unit 100 causes the seedling transplanter 1 to execute a turning process in which the seedling transplanter 1 turns 180 degrees to move from the straight movement process to the next straight movement process (next process).

The planned travel route R2 is, for example, a route (called a headland route) that combines a straight route and a turning route that turns 90 degrees in the headland area of the field F (meaning the inner peripheral area including the headland of the field F). On the headland route, the control unit 100 causes the seedling transplanter 1 to execute a headland process of planting seedlings in the headland area of the field F. Note that in Fig. 3, the work end point P- _E on the planned travel route R2 is not shown.

<Route adjustment tool>
Next, the course adjustment operation tool 80 (80A, 80B) will be described with reference to Figs. 4 to 7. Fig. 4 is an explanatory diagram of the arrangement of the course adjustment operation tool 80 (80A). Fig. 4 shows the arrangement of the course adjustment operation tool 80A when the course adjustment operation tool 80 (80A) is provided on the upper surface of the operation panel 29. Fig. 5 is an explanatory diagram of the operation of the course adjustment operation tool 80A. Fig. 6 is an explanatory diagram of course adjustment by operating the course adjustment operation tool 80A.

As described above, the control unit 100 (see FIG. 2) causes the seedling transplanter 1 to execute the straight-line process, the turning process, and the headland process based on the predetermined course information preset by the control unit 100. Here, for example, the course TR (see FIG. 6) of the seedling transplanter 1 after turning the machine body may deviate from the course information (the straight-line route R _S of the planned travel route R). In this case, in order to correct the course TR of the seedling transplanter 1, it is necessary to turn the autonomous travel mode (automatic turning) "OFF" once and then redo the machine body turning by manual operation.

When the seedling transplanter 1 is traveling autonomously with the operator (worker) seated in the operator's seat 26 (see FIG. 1), the course adjustment operation device 80 (80A, 80B) is operated by the operator (worker) when moving the seedling transplanter 1 a predetermined amount to the left or right of the current traveling direction of the vehicle, as described above. Note that the movement amount of the seedling transplanter 1 when the course adjustment operation device 80 (80A, 80B) is operated is preset by the control unit 100. In addition, the movement amount of the seedling transplanter 1 may be changed depending on the operation amount and operation time of the course adjustment operation device 80 (80A, 80B).

Such course adjustment operation tools 80 (80A, 80B) are provided near the steering handle 22 (see Figure 1) so that they are easy for the operator to operate.

As shown in FIG. 4, the course adjustment operation tool 80A is provided on the upper surface of the operation panel 29. As shown in FIG. 4, the course adjustment operation tool 80A is preferably arranged in area A1, which is the left side as seen from the pilot (operator). By arranging the course adjustment operation tool 80A in area A1, which is the left side of the upper surface of the operation panel 29 in this way, the arrangement makes it easy for the pilot (operator) to operate it from the steering handle 22 (see FIG. 1), for example, while operating the main shift lever 30 with his right hand. The course adjustment operation tool 80A may also be arranged in area A2, which is the right side as seen from the pilot (operator).

The course adjustment tool 80A may be located in area A3, which is on the left side as seen by the pilot (operator), behind the steering column 22a that supports the steering wheel 22, or in area A4, which is on the right side as seen by the pilot (operator). The course adjustment tool 80A may be located in area A5, which is in front (center) as seen by the pilot (operator), behind the steering column 22a.

In this way, by arranging the course adjustment operation tool 80A on the upper surface of the operation panel 29, the operator can adjust the course TR at his/her own timing. In addition, since the course adjustment operation tool 80A is provided in a position that is easy for the operator to operate, operability can be improved.

When the course adjustment operating device 80 (80A) is provided on the upper surface of the operation panel 29, it is preferable that the course adjustment operating device 80 (80A) is, for example, a toggle switch. As shown in FIG. 5, when the course adjustment operating device 80A is a toggle switch, there are three positions: "left", "right" and "center". Of these, the "left" position is a position where the seedling transplanter 1 is adjusted to the left, and the "right" position is a position where the seedling transplanter 1 is adjusted to the right. Furthermore, the "center" position is a position where no adjustment of the course TR of the seedling transplanter 1 is performed.

In this way, when the course adjustment operating tool 80 (80A) is a toggle switch, it is preferable that the tilt direction of the toggle switch corresponds to the movement (adjustment) direction of the seedling transplanter 1. Also, when the course adjustment operating tool 80 (80A) is a toggle switch, it is preferable that the toggle switch automatically returns to the "center" position when the operator (worker) releases his/her hand from the toggle switch that has been tilted to the "left" or "right" position.

As shown in Fig. 6, in the seedling transplanter 1, when the course TR is adjusted to the left, the course adjustment tool 80 (80A) is tilted to the "left" position, thereby adjusting (correcting) the course from the actual course TR to the left course TR _L. In addition, in the seedling transplanter 1, when the course TR is adjusted to the right, the course adjustment tool 80 (80A) is tilted to the "right" position, thereby adjusting (correcting) the course TR from the actual course TR to the right course TR _R. Note that the control unit 100 does not execute the adjustment (correction) of the course TR unless it is detected that the course adjustment tool 80 (80A) has been tilted for a certain period of time or more.

In this way, the control unit 100 (see FIG. 2) can adjust the path TR of the seedling transplanter 1 in the left-right direction during a process of planting seedlings such as the straight-line process. The control unit 100 may also adjust the path TR of the seedling transplanter 1 in the left-right direction during the headland process (a process of planting seedlings while moving straight in the headland process), which is a process of planting seedlings similar to the straight-line process. This allows the path TR to be adjusted in the left-right direction when the path TR of the seedling transplanter 1 deviates left-right during the straight-line process, for example, so that it is possible to prevent the occurrence of a situation in which the spacing between seedling planting rows is not kept constant due to the seedling transplanter 1 deviating left-right, thereby improving seedling planting performance.

Furthermore, when the control unit 100 adjusts the course TR of the seedling transplanter 1 during the straight-line process, it creates a planned travel route R (see FIG. 3) as new course information that reflects the adjustment of the course TR during the next straight-line process. In this way, the left-right direction is adjusted (corrected) during the next process (the straight-line process following the straight-line process in which the course TR was adjusted left-right), so the spacing between seedling planting rows can be kept constant. In addition, the accuracy of row alignment after the machine turns is improved, stabilizing the seedling planting start position, making this effective for seedling transplanters 1 in which the seedling planting start position is important.

The control unit 100 adjusts the course TR of the seedling transplanter 1 relative to a reference course that serves as a reference for the seedling transplanter 1 to travel autonomously. This allows the seedling transplanter 1 traveling autonomously to be adjusted left and right relative to the reference course. In addition, the control unit 100 creates course information (planned travel course R) before the seedling transplanter 1 travels autonomously. Therefore, when adjusting the course TR relative to the reference course, the control unit 100 creates course information (planned travel course R) by acquiring the reference course from the position information acquisition device 50 (see FIG. 2), for example, before the seedling transplanter 1 starts traveling autonomously.

The control unit 100 may also adjust the course TR of the seedling transplanter 1 relative to a reference orientation that serves as a reference for the seedling transplanter 1 to travel autonomously. This allows the seedling transplanter 1 traveling autonomously to be adjusted left and right relative to the reference orientation. The control unit 100 also creates course information (planned travel route R) before the seedling transplanter 1 travels autonomously. For this reason, when adjusting the course TR relative to the reference orientation, the control unit 100 creates course information (planned travel route R) by acquiring the reference orientation from the position information acquisition device 50, for example, before the seedling transplanter 1 starts traveling autonomously.

The control unit 100 may also adjust the course TR of the seedling transplanter 1 relative to a reference position (coordinates indicating the current position of the machine) that serves as a reference for the seedling transplanter 1 to travel autonomously. This allows the seedling transplanter 1 traveling autonomously to be adjusted left and right relative to the reference position (coordinates). The control unit 100 also creates course information (planned travel route R) before the seedling transplanter 1 travels autonomously. For this reason, when adjusting the course TR relative to the reference position (coordinates), the control unit 100 creates the course information (planned travel route R) by acquiring the reference position (coordinates) from the position information acquisition device 50, for example, before the seedling transplanter 1 starts traveling autonomously.

Furthermore, when creating the course information (planned travel route R), the control unit 100 resets the adjustment of the course TR if the course TR has been adjusted in the previous process. In this way, the adjustment of the course TR is reset before the seedling transplanter 1 starts autonomous travel, specifically, it returns to the teaching setting value of the planned travel route R, so that, for example, when work on the field F where the course TR has been adjusted is finished and work on the next field F is started, erroneous setting of the course TR, i.e., the planned travel route R that will become the subsequent course TR, can be prevented.

Figure 7 is an explanatory diagram of the arrangement of the course adjustment operating device 80 (80B). Note that Figure 7 shows the arrangement of the course adjustment operating device 80B when the course adjustment operating device 80 (80B) is provided on the main shift lever 30.

As shown in FIG. 7, the course adjustment operation tool 80 (80B) may be provided on the main shift lever 30 that is operated by the operator (worker) with the right hand. When the course adjustment operation tool 80B is provided on the main shift lever, it is provided on the outer circumferential surface of the grip 30a. The course adjustment operation tool 80B is preferably disposed in the upper front area A6 on the outer circumferential surface of the grip 30a. The course adjustment operation tool 80B may also be disposed in the upper rear area A7 on the outer circumferential surface of the grip 30a.

In this way, the course adjustment operation tool 80B is disposed on the outer peripheral surface of the grip 30a of the main shift lever 30, so that the operator can adjust the course TR (see FIG. 6) at his/her own timing. In addition, the course adjustment operation tool 80B is provided in a position that is easy for the operator to operate, improving operability.

When the course adjustment operating device 80B is provided on the main shift lever 30, it has three positions, "left," "right," and "center," just like the toggle switch configuration described above. In the "left" position, the seedling transplanter 1 is adjusted to the left, and in the "right" position, the seedling transplanter 1 is adjusted to the right. In addition, when the course adjustment operating device 80B is in the "center" position, no adjustment is made to the course TR of the seedling transplanter 1.

It is also preferable that the course adjustment operation tool 80B automatically returns to the "center" position when the operator removes his/her hand from the "left" or "right" position. Also, in the case of the course adjustment operation tool 8080B, if operation (e.g., pushing) of the course adjustment operation tool 80B for a certain period of time or more is not detected, course adjustment (correction) will not be performed.

<Remote Control>
Next, remote control of the seedling transplanter 1 by the remote control device 90 will be described with reference to Figures 8 and 9. Figures 8 and 9 are explanatory diagrams of remote control by the remote control device 90.

As shown in FIG. 8, when an operator W remotely operates the seedling transplanter 1 from a remote control device 90 such as a smartphone, the remote control device 90 communicates with the seedling transplanter 1 via a relay antenna 150 installed in the vicinity of the field F where the operator is to work. The remote control device 90 performs remote control using a smartphone app. The remote control device 90 also displays, in the smartphone app, a planned travel route R (see FIG. 3) that was generated by teaching the seedling transplanter 1 to travel autonomously.

As described above, the remote control device 90 has a short-distance wireless communication function and performs short-distance communication. Specifically, the remote control device 90 performs short-distance communication by Bluetooth (registered trademark). For example, the remote control device 90 communicates with the seedling transplanter 1 via the relay antenna 150 when the distance D1 to the relay antenna 150 is within 10 m. In this case, the distance D2 between the relay antenna 150 and the seedling transplanter 1 can be within 300 m.

In this way, by communicating via the relay antenna 150, battery consumption can be reduced, making it easier to use than a remote control with a liquid crystal display. For example, a remote control with a liquid crystal display consumes a lot of battery power and requires frequent battery replacement, while increasing the battery capacity of the remote control with a liquid crystal display increases the size, reducing portability and operability. However, in this embodiment, where communication is performed via the relay antenna 150, there is no need to increase the battery capacity, so portability and operability are not reduced, making it easy to use.

The relay antenna 150 can be carried by the worker W, and its installation location can be changed. Therefore, the relay antenna 150 can be installed in a position not too far from the worker W around the field F.

On the other hand, as shown in FIG. 9, when an operator W remotely operates the seedling transplanter 1 from a remote control device 90 such as a smartphone, the remote control device 90 communicates directly with the seedling transplanter 1 without going through the relay antenna 150 if the distance D3 between the remote control device 90 and the seedling transplanter 1 is within a predetermined range (for example, within 10 m).

In this way, by directly communicating with the seedling transplanter 1 when the distance D3 between the remote control device 90 and the seedling transplanter 1 is within a predetermined range, there is no need to go through the relay antenna 150 when the distance (distance D3) between the seedling transplanter 1 and the remotely operating operator W (remote control device 90) is close, for example when remotely operating the seedling transplanter 1 while checking the distance to the ridge at the edge of the field. This eliminates the need to install the relay antenna 150, for example, improving workability.

In addition, by using a smartphone that supports a Bluetooth (registered trademark) communication method with strong radio wave strength (long communication distance) (for example, "Bluetooth-Class 1") as the remote control device 90, the distance from the seedling transplanter 1 can be up to 100 m.

<Relay antenna>
Next, the relay antenna 150 will be described with reference to Fig. 10. Fig. 10 is an explanatory diagram of the relay antenna 150. Fig. 10 is a schematic perspective view of the relay antenna 150.

As shown in FIG. 10, the relay antenna 150 that transmits and receives radio waves is supported by a tripod-shaped support 151. For example, a camera tripod can be used as the tripod-shaped support 151. This makes it easy to obtain the support 151 for supporting the relay antenna 150, and also makes it easy to move and install the relay antenna 150.

The relay antenna 150 is also provided with a notification light 140. The notification light 140 uses, for example, multiple types (e.g., three types) of colors to notify the operator W (see FIG. 8) or the like of the status of the seedling transplanter 1 (see FIG. 1) by changing the display (illuminated color). The notification light 140 notifies of machine abnormalities and obstacle detection, as well as the type of mode currently being executed (autonomous driving mode, remote control mode, manual operation mode, etc.).

In this way, since the notification light 140 is provided on the relay antenna 150, the worker W can understand the status of the seedling transplanter 1 by looking at the relay antenna 150 even if the seedling transplanter 1 is difficult for the worker W to see, thereby improving workability. Note that the notification light 140 is usually provided on the seedling transplanter 1 side. In this case, the notification light 140 is provided in a position that is easily visible to the worker W, such as the upper front part of the traveling vehicle body 2 (see Figure 1).

<Fall prevention control for workers>
Next, a description will be given of fall prevention control for an operator (worker) riding on the seedling transplanter 1 with reference to Figures 11 and 12. Figures 11 and 12 are flow charts showing the process of fall prevention control for an operator W riding on the machine body (seedling transplanter 1).

The seedling transplanter 1 (see FIG. 1) described above is provided with a seating sensor (not shown) that detects the operator (worker) sitting in the cockpit 26 (see FIG. 1) when the operator (worker) is on board. The seating sensor is, for example, a pressure sensor, and is provided in the seat base or cushion part of the cockpit 26. Note that instead of the seating sensor, another sensor that detects the operator (worker) on board the aircraft may be used.

Here, in the seedling transplanter, for example, when the autonomous driving mode is assumed to be unmanned with no operator (worker) on board the machine, there is a possibility that the operator (worker) may be thrown off due to vibrations of the machine during autonomous driving. For this reason, the seedling transplanter 1 uses a seating sensor to prevent the operator (worker) from falling by controlling the output of the HST when the operator (worker) is on board the seedling transplanter 1 and delaying the timing when the seedling transplanter 1 starts moving.

As shown in FIG. 11, in a first example of control to prevent the operator (worker) from falling, when the control unit 100 (see FIG. 2) causes the seedling transplanter 1 to travel autonomously, when the seating sensor value and the HST motor sensor value are detected (step S101), the control unit 100 determines whether the operator (worker) is seated in the operator's seat 26 based on the seating sensor value (step S102).

When the control unit 100 determines in the process of step S102 that the operator (worker) is seated (step S102: Yes), it performs control to suppress the output of the HST (step S103). In this case, for example, the output of the HST is suppressed so that the opening degree of the HST is an upper limit of 80%. After the control unit 100 performs control to suppress the output of the HST, it ends the process.

If the control unit 100 determines in the processing of step S102 that the operator (operator) is not seated (step S102: No), it leaves the HST output at the default value (step S104) and ends the processing.

In this way, by suppressing the output of the HST when the operator (worker) is on board the seedling transplanter 1, it is possible to prevent the operator (worker) from falling, thereby improving safety.

As shown in FIG. 12, in a second example of control to prevent the operator (worker) from falling, when the control unit 100 causes the seedling transplanter 1 to travel autonomously, upon detecting the seating sensor value and the HST output timing (step S201), the control unit 100 determines whether the operator (worker) is seated in the operator's seat 26 based on the seating sensor value (step S202).

When the control unit 100 determines in the processing of step S202 that the operator (worker) is seated (step S202: Yes), it performs control to delay the timing at which the seedling transplanter 1 starts to move (step S203). In this case, for example, the timing at which the seedling transplanter 1 starts to move is delayed by about one second. After performing control to delay the timing at which the seedling transplanter 1 starts to move, the control unit 100 ends the processing.

When the control unit 100 determines in the processing of step S202 that the operator (worker) is not seated (step S202: No), it leaves the timing at which the seedling transplanter 1 starts moving at the default value (step S204) and ends the processing.

In this way, by delaying the timing at which the seedling transplanter 1 starts moving when the operator (worker) is on board the seedling transplanter 1, it is possible to prevent the operator (worker) from falling, thereby improving safety.

<Downsizing engine structure>
Next, the downsizing structure of the engine E of the seedling transplanter 1 will be described with reference to Figures 13 and 14. Figures 13 and 14 are explanatory diagrams of the downsizing structure of the engine E. Note that Figure 13 shows the engine E, the electric supercharger 160, and the air cleaner 170 in an exploded state, and Figure 14 shows the air flow paths 161, 162 of the electric supercharger 160.

As shown in Figures 13 and 14, in the seedling transplanter 1, an electric supercharger 160 is attached to the intake port of the engine E to boost the intake volume when the engine E is rotating at a low speed. When the intake pressure exceeds the boost pressure when the engine E is rotating at a high speed, the electric supercharger 160 is turned off. That is, as shown in Figure 14, when the engine E is rotating at a high speed, air flows through the air flow path (bypass flow path) 162, so the electric supercharger 160 is turned off.

As shown in Figures 13 and 14, the seedling transplanter 1 has a structure (downsizing structure) in which an electric supercharger 160 is provided between the engine E and the air cleaner 170, which allows for a smaller size and lighter weight (downsizing) and improved environmental performance. In recent years, seedling transplanters have become larger and more powerful, but the associated weight increase sacrifices wet-field maneuverability and turning ability. The seedling transplanter 1 can use a smaller class engine due to the downsizing structure described above, which allows for a reduction in the weight of the engine E. It is also less expensive than a turbo engine, and since seedling transplanters often use low speeds, the effect of the electric supercharger 160 is more pronounced, and the heat balance is also improved when downsizing is performed.

<Fertilizer clogging elimination control>
Next, the fertilizer clogging clearing control will be described with reference to Figures 15 to 18. Figure 15 is an explanatory diagram of fertilizer clogging in the feed device 42. Note that Figure 15 shows a schematic diagram of the feed device 42 for fertilizer G. Figures 16 to 18 are flow charts showing the process of the fertilizer clogging clearing control.

As shown in FIG. 15, the dispensing device 42 in the fertilizer application device 40 (see FIG. 1) supplies a predetermined amount of fertilizer G stored in the fertilizer hopper 41 to the fertilizer hose (not shown) (in other words, discharges a predetermined amount of fertilizer G from the fertilizer hopper 41) in the above-mentioned fertilizer application device 40. The dispensing device 42 is a so-called mechanically driven type that drives the dispensing rotor 421, which rotates in a predetermined direction RD to discharge fertilizer G from the fertilizer hopper 41, via gears. In the mechanically driven dispensing device 42, if there is insufficient driving force to rotate the dispensing rotor 421, the dispensing rotor 421 does not rotate and fertilizer G is not discharged, which is called fertilizer clogging. When fertilizer clogging occurs, an area where fertilizer G is not applied is created.

In the seedling transplanter 1, control is performed to assisted the mechanical drive of the delivery rotor 421 with motor drive with a high gear ratio (fertilizer clogging relief control).

As shown in FIG. 16, in the first example of fertilizer clogging removal control, when the driving rotation speed of the dispensing rotor 421 is detected (step S301), the control unit 100 (see FIG. 2) determines whether the dispensing rotor 421 is rotating poorly based on the driving rotation speed of the dispensing rotor 421 (step S302).

When the control unit 100 determines in the process of step S302 that the payout rotor 421 is not rotating properly (step S302: Yes), it performs control to add a constant amount of motor drive to the mechanical drive (step S303). After the control unit 100 adds a constant amount of motor drive, it performs control to stop the motor (step S304). When the motor stops, the payout rotor 421 becomes free. After performing control to stop the motor, the control unit 100 ends the process.

If the control unit 100 determines in the process of step S302 that the rotation of the payout rotor 421 is not defective (step S302: No), the control unit 100 returns to the process of step S301, and the driving rotation speed of the payout rotor 421 is detected.

In this way, by adding a constant amount of motor drive to the mechanical drive when the delivery rotor 421 is not rotating properly (fertilizer clogging), it is possible to eliminate the fertilizer clogging and prevent the creation of areas where no fertilizer G is applied.

In addition, the seedling transplanter 1 uses two motor systems, one of which has a higher gear ratio, and normally drives the discharge rotor 421 with the low-gear side motor with a lower gear ratio, and when the output current value of the low-gear side motor reaches or exceeds a predetermined value, the discharge rotor 421 is driven by the high-gear side motor with a higher gear ratio (fertilizer clogging relief control).

As shown in FIG. 17, in the second example of fertilizer clogging removal control, when the current value of the low gear side motor output is detected (step S401), the control unit 100 (see FIG. 2) determines whether the current value of the low gear side motor output is large (greater than or equal to a predetermined value) based on the detected current value (step S402).

When the control unit 100 determines in the process of step S402 that the current value is large (greater than or equal to a predetermined value) (step S402: Yes), it controls the high gear side motor to drive the payout rotor 421 for a fixed number of rotations (step S403). After driving the payout rotor 421 for a fixed number of rotations with the high gear side motor, the control unit 100 controls it to return to the low gear side motor (step S404), and ends the process when it has returned to the low gear side motor.

If the control unit 100 determines in step S402 that the current value is not large (less than the predetermined value) (step S402: No), the control unit 100 returns to step S401, and the current value of the low gear side motor output is detected.

In this way, when the current value of the low gear side motor output is large, i.e., when the current value is equal to or greater than a predetermined value (fertilizer clogging), the high gear side motor drives the payout rotor 421 for a fixed number of revolutions, thereby eliminating the fertilizer clogging and preventing the creation of areas where fertilizer G is not applied.

In addition, in the seedling transplanter 1, when crushed fertilizer G becomes clogged in the delivery rotor 421 and the load torque (current value) of the motor output exceeds a predetermined value, the motor output is reversed (positive and negative are switched) and controlled to output at a constant speed (fertilizer clogging removal control).

As shown in FIG. 18, in the third example of fertilizer clogging removal control, when the motor output current value is detected (step S501), the control unit 100 (see FIG. 2) determines whether the motor output current value is large (greater than or equal to a predetermined value) based on the detected current value (step S502).

When the control unit 100 determines in the process of step S502 that the current value is large (greater than or equal to a predetermined value) (step S502: Yes), it reverses the motor output (switches the positive and negative polarities) and then controls the motor output to be output at a constant speed (step S503). After the control unit 100 reverses the motor output and then outputs the motor output at a constant speed, it controls the motor output to be returned to its original state (for example, forward rotation) (step S504), and when the motor output is returned to its original state, the process ends.

If the control unit 100 determines in the process of step S502 that the current value is not large (less than the predetermined value) (step S502: No), the control unit 100 returns to the process of step S501, and the current value of the motor output is detected.

In this way, when the motor output current value is large, i.e., equal to or greater than a predetermined value (fertilizer clogging), the motor output is reversed and then output at a constant speed, thereby eliminating the fertilizer clogging and preventing the creation of areas where fertilizer G is not applied.

<Front sensor cover>
Next, the front sensor cover 180 will be described with reference to Figures 19 and 20. Figures 19 and 20 are explanatory diagrams of the front sensor cover 180 and are schematic perspective views of the front sensor cover 180. Note that Figure 19 shows the front sensor cover 180 in an upright position, and Figure 20 shows the front sensor cover 180 in a tilted position.

As shown in FIG. 19, the seedling transplanter 1 (see FIG. 1) is provided with a front sensor cover 180 that houses a front sensor for detecting obstacles in front of the machine body. The front sensor cover 180 is provided in front of the bonnet 28. The front sensor cover 180 is made of, for example, resin. The front sensor cover 180 is supported by a support frame 181 that can rotate in the forward and backward directions.

As shown in FIG. 20, the front sensor cover 180 can be tilted, for example, during refueling, so that the back surface of the front sensor cover 180 serves as a mounting portion 182 for a fuel tank or the like.

This type of front sensor cover 180 normally functions as a cover for the front sensor, and also functions as a bumper guard for the front part of the aircraft. The front sensor cover 180 also serves as the face of the aircraft, allowing it to be differentiated from other models.

<Turning Assist>
Next, the turning assistance in the seedling transplanter 1 (see FIG. 1) will be described.

During execution of turning assistance in the seedling transplanter 1 by the control unit 100 (see FIG. 2), the control unit 100 determines the slip rate from the ratio of the rotation speed of the front wheels 11 (see FIG. 1) to the rotation speed of the rear wheels 12 (see FIG. 1). In this case, slip is detected from the rotation speed of the front wheels 11, and the degree of slip is detected from the rotation speed of the rear wheels 12. In this case, it is good to look at the ratio of the rotation speed of the rear wheels 12 to the rotation speed of the diagonal front wheels 11, and if the ratio of the rotation speed of the rear wheels 12 to the rotation speed of the front wheels 11 is equal to or greater than a predetermined value, it is determined that slip has occurred. This configuration can improve the accuracy of the turning assistance, and can prevent slippage during turning of the vehicle during autonomous driving from affecting the accuracy of seedling planting row alignment.

In addition, while turning assistance is being performed, the control unit 100 can detect the degree of slippage by estimating it from the rotation speed of the inner wheel of the rear wheel 12 when the clutch is disengaged (comparing it with the rotation speed of the outer wheel, and detecting slippage when there is no rotation).

Furthermore, when performing turning assistance, the control unit 100 takes into account the deviation from the parallel lines stored for straight-line assistance, i.e., the degree to which the orientation of the aircraft before the start of automatic turning has deviated from the straight-line path R _S (see FIG. 3 ), and changes the time for returning the steering wheel 22 (see FIG. 1 ) depending on the degree of deviation from the straight-line path R _S.

In the seedling transplanter 1, the timing of the aircraft rotation is determined by the position information acquisition device 50 (for example, a GNSS device), but it may also be configured to store the drive rotation speed as a backup, so that even if the satellite is lost, it is possible to obtain a certain degree of appropriate rotation timing. In addition, in order to adapt to not only rectangular fields F but also irregular fields F such as trapezoids, the seedling transplanter 1 may be configured to predict the length of the next path (third path) by, for example, differential calculation by taking the difference in distance between the first path and the second path during teaching for autonomous driving. In addition, in the seedling transplanter 1, the rotation sensor may be configured to be fixed to the transmission, which makes it an inexpensive system that does not use a GNSS device or the like.

The above-described embodiment realizes the following seedling transplanter 1.

(1) A seedling transplanter 1 capable of autonomous travel, which performs seedling planting work while autonomously traveling within a field F, is equipped with a control unit 100 that causes the seedling transplanter 1 to execute a straight line process of planting seedlings while traveling straight, a turning process for transitioning from the straight line process to the next straight line process, and a headland process of planting seedlings in a headland area of the field F, based on predetermined course information (planned travel route R), and the control unit 100 is capable of adjusting the course TR of the seedling transplanter 1 in the left-right direction while the seedling planting process is being performed.

With this type of seedling transplanter 1, for example, if the path TR of the seedling transplanter 1 deviates left or right during the straight-line process, the path TR can be adjusted left or right, preventing the occurrence of a situation in which the spacing between seedling planting rows is not kept constant due to the seedling transplanter 1 deviating left or right, thereby improving seedling planting performance.

(2) In the above (1), when the control unit 100 adjusts the course TR during the straight-line process, the seedling transplanter 1 creates new course information (planned driving route R) that reflects the adjustment of the course TR during the next straight-line process.

In addition to the effect of (1) above, such a seedling transplanter 1 creates new course information (planned travel route R) that reflects the adjustments made in the next process (the straight-line process following the straight-line process in which the course TR was adjusted left and right), so the left and right directions are adjusted (corrected) in the next process. This makes it possible to keep the spacing between seedling planting rows constant. In addition, the accuracy of row alignment after the machine turns is improved, stabilizing the seedling planting start position, making this effective for seedling transplanters 1 in which the seedling planting start position is important.

(3) In the above (1) or (2), the control unit 100 adjusts the course TR relative to a reference path that serves as a reference for the seedling transplanter 1 to travel autonomously.

In addition to the effects of (1) or (2) above, such a seedling transplanter 1 allows the autonomously traveling seedling transplanter 1 to be adjusted left and right relative to the reference path.

(4) In the above (1) or (2), the control unit 100 adjusts the course TR to a reference direction that serves as a reference for the seedling transplanter 1 to travel autonomously.

In addition to the effects of (1) or (2) above, such a seedling transplanter 1 allows the autonomously traveling seedling transplanter 1 to be adjusted left and right relative to a reference orientation.

(5) In the above (1) or (2), the control unit 100 adjusts the course TR relative to a reference position that serves as a reference for the seedling transplanter 1 to travel autonomously.

In addition to the effects of (1) or (2) above, such a seedling transplanter 1 allows the autonomously traveling seedling transplanter 1 to be adjusted left and right relative to a reference position (coordinates).

(6) In any one of (3) to (5) above, before the seedling transplanter 1 starts to travel autonomously, the control unit 100 acquires the reference route and creates the route information (planned travel route R) if the course TR is adjusted relative to a reference route that is the reference for the seedling transplanter 1 to travel autonomously, or acquires the reference orientation and creates the route information (planned travel route R) if the course TR is adjusted relative to a reference orientation that is the reference for the seedling transplanter 1 to travel autonomously, or acquires the reference position and creates the route information (planned travel route R) if the course TR is adjusted relative to a reference position that is the reference for the seedling transplanter to travel autonomously, and resets the adjustment of the course TR if the course TR was adjusted in the previous process when creating the course information (planned travel route R).

In addition to any one of the effects (3) to (5) above, such a seedling transplanter 1 resets the adjustment of the course TR before the seedling transplanter 1 starts traveling autonomously, so that, for example, when work on a field F where the course TR was adjusted is completed and work on a new field F is started, it is possible to prevent erroneous setting of the course TR (the planned travel route R that will become the subsequent course TR).

(7) In any one of the above (1) to (6), the seedling transplanter 1 includes a steering handle 22 for steering the seedling transplanter 1, a main speed change lever 30 for changing the speed of the seedling transplanter 1, and a course adjustment operation tool 80 that is provided around the steering handle 22 and is operated by an operator W when adjusting the course TR by the control unit 100, and the course adjustment operation tool 80 (80B) is provided on the outer peripheral surface of the grip 30a of the main speed change lever 30.

In addition to any one of the effects (1) to (6) above, such a seedling transplanter 1 allows, for example, when an operator W is riding on the seedling transplanter 1, the course TR to be adjusted at the operator W's timing. Also, the course adjustment operating tool 80 (80B) is provided at a position that makes it easy for the operator W to operate, improving operability.

(8) In any one of (1) to (7) above, the seedling transplanter 1 further includes a remote control device 90 for remotely controlling the seedling transplanter 1, the remote control device 90 having a short-range wireless communication function, a changeable installation position, and communicating with the seedling transplanter 1 via a relay antenna 150 installed in the vicinity of the field F.

In addition to any one of the effects (1) to (7) above, this seedling transplanter 1 can reduce battery consumption by using the relay antenna 150, making it easier to use than a remote control with a liquid crystal display, etc.

(9) In the above (8), the remote control device 90 communicates directly with the seedling transplanter 1 without going through the relay antenna 150 when the distance D3 from the seedling transplanter 1 is within a predetermined range.

In addition to the effect of (8) above, with this seedling transplanter 1, when the distance D3 between the seedling transplanter 1 and the operator W remotely operating it is within a predetermined range (distance where short-range wireless communication is possible), such as when remotely operating the seedling transplanter 1 while checking the distance between the ridge and the ridge, there is no need to go through the relay antenna 150. This eliminates the need to install the relay antenna 150, for example, and improves workability.

(10) In the above (8) or (9), the relay antenna 150 is provided with an indicator light 140 that indicates the status of the seedling transplanter 1 by changing the display.

In addition to the effects of (8) or (9) above, such a seedling transplanter 1 has a notification light 140 provided on the relay antenna 150, so that the worker W can grasp the status of the seedling transplanter 1 by looking at the relay antenna 150 even if the seedling transplanter 1 is difficult for the worker W to see. This improves workability.

Further advantages and modifications may readily occur to those skilled in the art. Therefore, the invention in its broader aspects is not limited to the specific details and representative embodiments shown and described above. Accordingly, various modifications may be made without departing from the spirit or scope of the general inventive concept as defined by the appended claims and equivalents thereof.

REFERENCE SIGNS LIST 1 seedling transplanter 22 steering handle 30 main shift lever 30a grip 80 course adjustment operation tool 90 remote operation tool 100 control unit 140 notification light 150 relay antenna D3 distance F field R course information (planned driving route)
TR Path W Worker

Claims (5)

A seedling transplanter that is capable of autonomous travel and performs seedling planting work while autonomously traveling in a farm field,
a control unit that causes the seedling transplanter to execute a straight-line process of planting seedlings while moving straight, a turning process for transitioning from the straight-line process to the next straight-line process, and a headland process of planting seedlings in a headland area of the field, based on predetermined course information;
A toggle switch that receives an adjustment operation of the path of the seedling transplanter,
The control unit is
The path of the seedling transplanter can be adjusted in the left and right directions during the seedling planting process.
When the toggle switch is tilted by an operator, the path of the seedling transplanter is adjusted according to the tilt;
When the operator no longer tilts the toggle switch, the toggle switch returns to a position where the path of the seedling transplanter is not adjusted, and the path adjustment is reset ;
A remote control device for remotely controlling the seedling transplanter
Further equipped with
The remote control device includes:
It has short-range wireless communication capabilities,
The installation position can be changed, and the device communicates with the seedling transplanter via a relay antenna installed around the field.
A seedling transplanter characterized by: The control unit is
The seedling transplanter according to claim 1, characterized in that when the course adjustment is made in the straight-line process, new course information is created in the next straight-line process that reflects the adjustment of the course. A steering handle for steering the seedling transplanter;
A main speed change lever for changing the speed of the seedling transplanter;
a course adjustment operation tool that is provided around the steering handle and that is operated by an operator when the control unit is to adjust the course,
The course adjustment operation tool is
The seedling transplanter according to claim 1 or 2, characterized in that the main speed change lever is provided on an outer peripheral surface of a grip of the main speed change lever. The remote control device includes:
2. The seedling transplanter according to claim 1 , wherein when the distance from the seedling transplanter is within a predetermined range, communication is performed directly with the seedling transplanter without going through the relay antenna. 5. The seedling transplanter according to claim 1, wherein the relay antenna is provided with an indicator light for indicating a state of the seedling transplanter by changing an indication.

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