JP7160875B2 - work vehicle controller - Google Patents

Description

The present invention mainly relates to a work vehicle control device capable of autonomously driving a work vehicle along a travel route.

Conventionally, there has been known a work vehicle capable of switching between a travel mode in which the work vehicle is manually traveled and a travel mode in which the work vehicle is autonomously traveled (automatically traveled). Patent Literature 1 discloses this type of work vehicle.

Patent Document 1 describes that the forward/reverse switching means must be neutral as a condition for shifting from a travel mode in which the work vehicle is manually traveled to a travel mode in which the work vehicle is autonomously traveled.

JP 2014-182453 A

However, if it is necessary for the forward/reverse switching means to be in neutral when switching the traveling mode, it is necessary to stop the work vehicle each time the traveling mode is switched. Therefore, it has not been possible to smoothly shift from a travel mode in which the work vehicle is manually traveled to a travel mode in which the work vehicle is autonomously traveled.

SUMMARY OF THE INVENTION The present invention has been made in view of the above circumstances, and its main object is to enable control for smoothly shifting a work vehicle from a travel mode in which the work vehicle is manually traveled to a travel mode in which the work vehicle is autonomously traveled. To provide a work vehicle control device capable of confirming whether or not an operator has an intention of automatic traveling.

Means and Effects for Solving Problems

The problems to be solved by the present invention are as described above. Next, the means for solving the problems and the effects thereof will be described.

According to the aspect of the present invention, a work vehicle control device having the following configuration is provided. That is, the work vehicle control device includes a forward/reverse control section and a travel mode control section. The forward/rearward travel control unit controls forward/rearward travel of the work vehicle. The travel mode control unit controls a manual travel mode in which the work vehicle moves forward and backward according to the operation of an operation tool provided on the work vehicle, and a forward and backward motion of the work vehicle without depending on the operation of the operation tool. One driving mode is executed from a plurality of driving modes including at least the autonomous driving mode to be controlled. The driving mode control unit executes the autonomous driving mode by satisfying an autonomous driving start condition. The forward/reverse switching operation tool included in the work vehicle can be switched between at least a forward position, a neutral position, and a reverse position. The autonomous travel start condition can be satisfied when the forward/reverse switching operation tool is in the forward position. When the autonomous driving mode is executed with the forward/rearward switching operation tool positioned at the forward position, the driving mode control unit controls the forward/rearward movement before a predetermined time elapses after execution of the autonomous driving mode. When the switching operation tool is not changed to the neutral position, a warning is issued to the effect that the autonomous running mode will end.

As a result, even when the forward/reverse switching operation tool is in the forward position, the conditions for starting autonomous travel are satisfied, so that the work vehicle can be shifted from manual travel to autonomous travel without stopping. In addition, it is possible to confirm that the operator has made the transition to autonomous travel. Therefore, switching from manual driving to autonomous driving can be performed smoothly, and safety can be improved.

In the work vehicle control device, the traveling mode control unit continues the autonomous traveling mode when the forward/reverse switching operation tool is changed to the neutral position before the predetermined period of time elapses.

As a result, the autonomous traveling mode can be continued while the forward/reverse switching operation tool is positioned at the neutral position, so that the work vehicle can be prevented from moving regardless of the operator's intention.

The running mode control section terminates the autonomous running mode when the forward/reverse switching operation tool is not changed to the neutral position before the predetermined period of time elapses.

As a result, it is possible to prevent the autonomous traveling mode from continuing while the forward/reverse switching operation tool is in the forward position, so that when returning to manual traveling again, the work vehicle moves regardless of the operator's intention. can be prevented.

BRIEF DESCRIPTION OF THE DRAWINGS The side view which shows the whole structure of a tractor provided with the control apparatus which concerns on one Embodiment of this invention. The top view of a tractor. The figure which shows a wireless-communications terminal. FIG. 2 is a block diagram showing the main configuration of the control system of the tractor and wireless communication terminal; Explanatory drawing which shows the transition conditions of driving mode types and driving modes. 4 is a flowchart showing a process of identifying a work route on which autonomous travel can be started; FIG. 4 is a diagram showing work route candidates on which autonomous travel can be started; FIG. 5 is a diagram for explaining conditions for determining whether or not the work route allows autonomous travel to start;

Next, embodiments of the present invention will be described with reference to the drawings. Below, the same reference numerals are given to the same members in each figure of the drawings, and redundant description may be omitted. In addition, the names of members and the like corresponding to the same reference numerals may be simplified, or may be replaced with names of higher-level concepts or lower-level concepts.

An autonomous traveling system autonomously travels one or more work vehicles in a work area and a non-work area to perform all or part of work. In this embodiment, a tractor is used as a working vehicle. machine is also included. In this specification, the term "autonomous travel" means that the tractor travels along a predetermined route under the control of a configuration related to travel provided by the tractor by a control unit (ECU) provided in the tractor. It means that the configuration related to the work of the tractor is controlled by the control unit of the tractor, and the tractor performs the work along a predetermined route. It should be noted that autonomous traveling and autonomous work include cases where a person is on the tractor and cases where no person is on the tractor. On the other hand, manual travel/manual work means that each component of the tractor is operated by the user to travel/work.

Next, embodiments of the present invention will be described with reference to the drawings. FIG. 1 is a side view showing the overall configuration of a tractor 1 provided in an autonomous traveling system 99 according to one embodiment of the invention. FIG. 2 is a plan view of the tractor 1. FIG. FIG. 3 is a diagram showing the wireless communication terminal 46. As shown in FIG. FIG. 4 is a block diagram showing the main configuration of the control system of the tractor 1 and wireless communication terminal 46. As shown in FIG.

As shown in FIG. 1 , the tractor 1 provided in the autonomous traveling system 99 is a work vehicle operated by wireless communication with the wireless communication terminal 46 . By the user operating the wireless communication terminal 46 and appropriately exchanging signals with the control unit (work vehicle control device) 4 of the tractor 1, the tractor 1 can be caused to travel and work autonomously.

First, the tractor 1 provided in the autonomous driving system 99 will be described mainly with reference to FIGS. 1 and 2. FIG.

The tractor 1 includes a traveling body (body portion) 2 capable of autonomously traveling within a field (traveling area). A working machine 3 shown in FIGS. 1 and 2 is detachably attached to the traveling body 2 . As the work machine 3, for example, there are various work machines such as a cultivator, a plow, a fertilizer applicator, a lawn mower, and a seed machine. 2 can be installed. The traveling machine body 2 is configured such that the height and attitude of the work machine 3 mounted thereon can be changed.

The configuration of the tractor 1 will be described in more detail with reference to FIGS. 1 and 2. FIG. As shown in FIG. 1, the traveling body 2 of the tractor 1 has a front portion supported by a pair of left and right front wheels (wheels) 7, and a rear portion supported by a pair of left and right rear wheels 8, 8. there is

A bonnet 9 is arranged on the front part of the traveling body 2 . An engine 10 which is a driving source of the tractor 1 and a fuel tank (not shown) are accommodated in the bonnet 9 . The engine 10 can be configured by, for example, a diesel engine, but is not limited to this, and may be configured by, for example, a gasoline engine. Also, an electric motor may be used as the drive source in addition to or instead of the engine.

A cabin 11 for a user to board is arranged behind the bonnet 9 . Inside the cabin 11, there are a steering handle (steering operation tool) 12 for the user to perform steering operation, a seat 13 on which the user can sit, and various operation tools for performing various operations. is mainly provided. However, the work vehicle such as the tractor 1 is not limited to the one with the cabin 11 and may be one without the cabin 11 .

2, a monitor device 14, a throttle lever 15, a main gear lever 27, a plurality of hydraulic operating levers 16, a PTO switch 17, a PTO gear lever 18, an auxiliary gear lever 19, and a forward/reverse switching lever 25. , the parking brake 26, the working machine lift switch 28, the brake pedal 61, the clutch pedal 62, the accelerator pedal 63, and the like. These operating devices are arranged near the seat 13 or near the steering handle 12 .

The monitor device 14 is configured to be able to display various information about the tractor 1 . The throttle lever 15 is an operating tool for setting the rotation speed of the engine 10 . The main shift lever 27 is an operation tool for changing the running speed of the tractor 1 steplessly. The hydraulic operating lever 16 is an operating tool for switching a hydraulic external extraction valve (not shown). The PTO switch 17 is an operation tool for switching transmission/interruption of power to a PTO shaft (not shown) projecting from the rear end of the transmission 22 (power take-off shaft). That is, when the PTO switch 17 is in the ON state, power is transmitted to the PTO shaft, the PTO shaft rotates, and the working machine 3 is driven. As a result, the PTO shaft does not rotate, and the working machine 3 is stopped. The PTO speed change lever 18 is used to change the power input to the working machine 3, and more specifically, it is an operation tool for changing the rotation speed of the PTO shaft. The sub-transmission lever 19 is an operation tool for switching the gear ratio of the traveling sub-transmission gear mechanism in the transmission 22 . The forward/reverse switching lever 25 is configured to be switchable between a forward position, a neutral position, and a reverse position. When the forward/reverse switching lever 25 is in the forward position, the power of the engine 10 is transmitted to the rear wheels 8 so that the tractor 1 moves forward. When the forward/reverse switching lever 25 is in the neutral position, the tractor 1 does not move forward or backward. When the forward/reverse switching lever 25 is positioned at the reverse position, the power of the engine 10 is transmitted to the rear wheels 8 so that the tractor 1 moves backward. A parking brake (braking operation tool) 26 is an operation tool that is manually operated by a user to generate a braking force, and is used, for example, when stopping the tractor 1 for a while. The working machine lifting switch 28 is an operation tool for raising and lowering the height of the working machine 3 mounted on the traveling body 2 within a predetermined range. A brake pedal (braking operation tool) 61 is an operation tool that is operated by a user's foot to generate a braking force. The clutch pedal 62 is an operation tool for switching transmission/non-transmission of the clutch with the user's foot. The accelerator pedal 63 is an operating tool that increases the rotation speed of the engine 10 . An accelerator lever may be arranged instead of or in addition to the accelerator pedal 63 .

As shown in FIG. 1 , a chassis 20 of the tractor 1 is provided below the traveling body 2 . The chassis 20 includes a body frame 21, a transmission 22, a front axle 23, a rear axle 24, and the like.

The body frame 21 is a supporting member in the front part of the tractor 1, and supports the engine 10 directly or via a vibration isolating member or the like. The transmission 22 changes the power from the engine 10 and transmits it to the front axle 23 and the rear axle 24 . The front axle 23 is configured to transmit power input from the transmission 22 to the front wheels 7 . The rear axle 24 is configured to transmit power input from the transmission 22 to the rear wheels 8 .

As shown in FIG. 4, the tractor 1 operates the traveling body 2 (forward, backward, stop, turn, etc.), traveling modes (manual traveling mode, autonomous traveling mode, etc.), and operations of the work machine 3 (elevating, driving, etc.). and stop, etc.) and perform processing related to the route. Therefore, the control unit 4 includes a forward/reverse control unit 4a that controls forward/backward movement, a driving mode control unit 4b, and a route processing unit 4c. The control unit 4 includes a CPU, ROM, RAM, and I/O (not shown), and the CPU can read and execute various programs from the ROM. The control unit 4 is electrically connected to a controller for controlling each component (for example, the engine 10, etc.) provided in the tractor 1, a wireless communication unit 40 capable of wireless communication with other wireless communication devices, and the like. ing.

As the controllers, the tractor 1 includes at least an engine controller, a vehicle speed controller, a steering controller, and an elevation controller (not shown). Each controller can control each component of the tractor 1 according to the electrical signal from the control unit 4 .

The engine controller controls the rotational speed of the engine 10 and the like. Specifically, the engine 10 is provided with a governor device 41 having an unillustrated actuator that changes the rotational speed of the engine 10 . The engine controller can control the rotation speed of the engine 10 by controlling the governor device 41 . The engine 10 is also provided with a fuel injection device 45 that adjusts the injection timing and injection amount of fuel to be injected (supplied) into the combustion chamber of the engine 10 . By controlling the fuel injection device 45 , the engine controller can stop the supply of fuel to the engine 10 and stop driving the engine 10 , for example.

A vehicle speed controller controls the vehicle speed of the tractor 1 . Specifically, the transmission 22 is provided with a transmission 42 that is, for example, a movable swash plate type hydraulic continuously variable transmission. The vehicle speed controller can change the gear ratio of the transmission 22 by changing the angle of the swash plate of the transmission 42 using an actuator (not shown) to achieve a desired vehicle speed.

The steering controller controls the rotation angle of the steering handle 12 . Specifically, a steering actuator 43 is provided at an intermediate portion of the rotating shaft (steering shaft) of the steering handle 12 . With this configuration, when the tractor 1 travels along a predetermined route, the control unit 4 calculates an appropriate rotation angle of the steering handle 12 so that the tractor 1 travels along the route. A control signal is output to the steering controller so as to achieve the rotation angle. The steering controller drives the steering actuator 43 based on the control signal input from the control unit 4 to control the rotation angle of the steering handle 12 .

The lift controller controls the lift of the working machine 3 . Specifically, the tractor 1 includes an elevation actuator 44 such as a hydraulic cylinder in the vicinity of the three-point link mechanism that connects the working machine 3 to the traveling machine body 2 . With this configuration, the elevation controller drives the elevation actuator 44 based on the control signal input from the control unit 4 to appropriately raise and lower the working machine 3, thereby performing agricultural work with the working machine 3 at a desired height. It can be carried out. By this control, the working machine 3 can be supported at a desired height such as a retraction height (a height at which farm work is not performed) and a working height (a height at which farm work is performed).

Note that the plurality of controllers (not shown) described above control each unit such as the engine 10 based on signals input from the control unit 4. Therefore, it is assumed that the control unit 4 substantially controls each unit. can grasp.

The tractor 1 equipped with the control unit 4 as described above controls each part of the tractor 1 (the traveling body 2, the working machine 3, etc.) by the control unit 4 when the user enters the cabin 11 and performs various operations. It is configured so that the farm work can be performed while running in the field. Further, the tractor 1 is capable of autonomous traveling and autonomous work based on a predetermined control signal output from the wireless communication terminal 46 while the user is on the tractor 1 . Note that the tractor 1 has a function of allowing the tractor 1 to travel autonomously even when the user is not on the tractor 1 .

Specifically, as shown in FIG. 4 and the like, the tractor 1 has various configurations for enabling autonomous travel and autonomous work. For example, the tractor 1 is provided with a positioning antenna 6 and the like necessary for acquiring position information of itself (the traveling body 2) based on the positioning system. With such a configuration, the tractor 1 can acquire its own position information based on the positioning system and travel autonomously on the field.

Next, the configuration of the tractor 1 for enabling autonomous travel will be described in more detail. Specifically, the tractor 1 of this embodiment includes a positioning antenna 6, a wireless communication antenna 48, a front camera 56, a rear camera 57, a storage unit 55, a vehicle speed sensor 53, and a An angle sensor 52 and the like are provided. In addition to these, the tractor 1 is equipped with an inertial measurement unit (IMU) capable of specifying the attitude (roll angle, pitch angle, yaw angle) of the traveling body 2 .

The positioning antenna 6 receives signals from positioning satellites that form a positioning system such as the Global Positioning System (GNSS). As shown in FIG. 1 , the positioning antenna 6 is attached to the top surface of the roof 92 of the cabin 11 of the tractor 1 . A positioning signal received by the positioning antenna 6 is input to a position information acquiring section 49 as a position detecting section shown in FIG. The position information acquisition unit 49 calculates and acquires the position information of the traveling body 2 (strictly speaking, the positioning antenna 6) of the tractor 1 as latitude/longitude information, for example. The position information acquired by the position information acquisition unit 49 is input to the control unit 4 and used for autonomous travel.

In this embodiment, a high-precision satellite positioning system using the GNSS-RTK method is used. good too. For example, relative positioning (DGPS) or geostationary satellite augmentation system (SBAS) could be used.

The wireless communication antenna 48 receives signals from the wireless communication terminal 46 operated by the user and transmits signals to the wireless communication terminal 46 . As shown in FIG. 1 , the wireless communication antenna 48 is attached to the upper surface of the roof 92 of the cabin 11 of the tractor 1 . A signal from the wireless communication terminal 46 received by the wireless communication antenna 48 is input to the control unit 4 after signal processing by the wireless communication unit 40 shown in FIG. A signal to be transmitted from the control unit 4 or the like to the wireless communication terminal 46 is processed by the wireless communication unit 40 , transmitted from the wireless communication antenna 48 and received by the wireless communication terminal 46 .

The front camera 56 is for photographing the front of the tractor 1 . The rear camera 57 is for photographing the rear of the tractor 1 . A front camera 56 and a rear camera 57 are mounted on the roof 92 of the tractor 1 . The moving image data captured by the front camera 56 and the rear camera 57 is transmitted from the wireless communication antenna 48 to the wireless communication terminal 46 by the wireless communication unit 40 . The radio communication terminal 46 that has received the moving image data displays the contents on the display 37 .

The vehicle speed sensor 53 is for detecting the vehicle speed of the tractor 1, and is provided on the axle between the front wheels 7, 7, for example. Data of the detection result obtained by the vehicle speed sensor 53 is output to the control unit 4 . The vehicle speed of the tractor 1 may be calculated based on the travel time of the tractor 1 over a predetermined distance based on the positioning antenna 6 instead of being detected by the vehicle speed sensor 53 . The steering angle sensor 52 is a sensor that detects the steering angles of the front wheels 7,7. In this embodiment, the steering angle sensor 52 is provided on a kingpin (not shown) provided on the front wheels 7 , 7 . Data of the detection result obtained by the steering angle sensor 52 is output to the control section 4 . Note that the steering angle sensor 52 may be provided on the steering handle 12 .

The storage unit 55 stores the travel route for autonomously traveling the tractor 1 and the work route for autonomous work, and stores the position transition (traveling trajectory) of the tractor 1 (strictly speaking, the positioning antenna 6) during autonomous travel. It is a memory that In addition, the storage unit 55 stores various information necessary for the tractor 1 to travel and work autonomously.

The wireless communication terminal 46 is configured as a tablet personal computer having a touch panel 39, as shown in FIG. The user can refer to and confirm information displayed on the display 37 of the wireless communication terminal 46 (for example, information from the front camera 56, the rear camera 57, the vehicle speed sensor 53, etc.). Further, the user operates the touch panel 39 or the hardware keys 38 or the like arranged near the display 37 to send a control signal (for example, temporary stop signal, etc.). It should be noted that the wireless communication terminal 46 is not limited to a tablet personal computer, and instead may be configured by a notebook personal computer, for example. In addition, when the tractor 1 is caused to perform autonomous traveling and autonomous work with a user on board, the tractor 1 side (for example, the monitor device 14) may have the same function as the wireless communication terminal 46.

The tractor 1 configured as described above travels along the traveling route P on the field based on the instruction of the user using the wireless communication terminal 46, and performs agricultural work with the working machine 3 along the working route P1. can be done.

Specifically, by performing various settings using the wireless communication terminal 46, the user can set a linear or polygonal work path P1 for agricultural work and an arc-shaped turning path connecting the ends of the work path P1. (Non-work path on which the tractor 1 turns) P2 can be generated as a series of paths P2 alternately (see FIG. 7). Information on the travel route (work route P1 and non-work route P2) P generated in this manner is input (transferred) to the storage unit 55 electrically connected to the control unit 4 of the tractor 1, and a predetermined By operating the tractor 1, the controller 4 controls the tractor 1 so that the tractor 1 can autonomously travel along the travel route P, and the work machine 3 can autonomously work along the work route P1.

The configuration of the wireless communication terminal 46 will be described in more detail below with reference to FIGS. 3 to 5. FIG.

As shown in FIGS. 3 and 4, the wireless communication terminal 46 of the present embodiment includes a display 37, hardware keys 38, and a touch panel 39, as well as a display control unit 31 and a storage unit 32 as main components of the control system. , an agricultural field acquisition unit 33, a work area acquisition unit 34, a travel route acquisition unit 35, and the like.

Specifically, the wireless communication terminal 46 is configured as a computer as described above, and includes a CPU, a ROM, a RAM, and the like. Further, the ROM stores appropriate programs for causing the tractor 1 to perform autonomous traveling and autonomous work. The cooperation of this software and hardware allows the wireless communication terminal 46 to operate as the display control unit 31, the storage unit 32, the farm field acquisition unit 33, the work area acquisition unit 34, the traveling route acquisition unit 35, and the like.

The display control unit 31 creates display data to be displayed on the display 37 and appropriately controls display contents. For example, the display control unit 31 causes the display 37 to display a predetermined monitoring screen, instruction screen, etc. while the tractor 1 is autonomously traveling along the travel route P and performing autonomous work along the work route P1.

The storage unit 32 stores the information about the tractor 1 and the information about the farm field input by the user by operating the touch panel 39 of the wireless communication terminal 46, and stores the created travel route P (the working route P1 and the non-working route P2). ) is a memory for storing information such as

The agricultural field acquisition unit 33 stores the position and shape of the agricultural field (traveling area) on which the tractor 1 performs autonomous traveling and autonomous work. The position and shape of the field are obtained by, for example, the user riding the tractor 1 and driving the tractor 1 around the circumference of the field and recording the transition of the position information of the positioning antenna 6 at that time. can do. The position and shape of the farm field acquired by the farm field acquisition unit 33 are stored in the storage unit 32 as farm field information.

The work area acquisition unit 34 sets the position of the work area where the tractor 1 performs agricultural work, which is arranged in the target field in which the tractor 1 travels autonomously. Specifically, the wireless communication terminal 46 of the present embodiment is configured to be able to set the width of the headland and the width of the non-cultivated land by performing a predetermined operation. Then, the non-work area consisting of the headland and the non-cultivated land is determined based on the above-described settings and the position and shape of the farm field acquired by the farm field acquisition unit 33. is defined as the work area.

The travel route acquisition unit 35 alternately connects a work route P1 along which the tractor 1 autonomously performs farm work in a field and a non-work route (turning route) P2 that connects the ends of the work route P1. Generate and obtain P. When the user inputs information necessary for generating the travel route P through the touch panel 39 or the like, the travel route acquisition unit 35 automatically creates the travel route P (the work route P1 and the non-work route P2) based on the information. . The travel path P is generated so that the work path P1 in the shape of a straight line or a polygonal line is included in the work area, and the non-work path (turning path) P2 is included in the non-work area such as a headland. The travel route P generated by the travel route acquisition unit 35 is stored in the storage unit 32 .

The user appropriately operates the wireless communication terminal 46 to input (transfer) the information of the travel route P generated by the travel route acquisition unit 35 to the storage unit 55 of the tractor 1 . After that, the user places the tractor 1 at the start position of the travel route P by riding and driving the tractor 1 . Subsequently, the user gets off the tractor 1 and operates the wireless communication terminal 46 to instruct the start of autonomous travel/autonomous work. As a result, the control unit 4 controls the travel and farm work of the tractor 1 so that the tractor 1 travels along the travel route P and performs farm work along the work route P1.

Next, processing for switching the traveling mode of the tractor 1 will be described with reference to FIGS. 5 to 8. FIG. FIG. 5 is an explanatory diagram showing types of driving modes and transition conditions of the driving modes. FIG. 6 is a flowchart showing a process of identifying a work route on which autonomous travel can start. FIG. 7 is a diagram showing candidates for work routes on which autonomous travel is possible. FIG. 8 is a diagram for explaining conditions for determining whether or not the work route allows autonomous travel.

By operating the touch panel 39 of the wireless communication terminal 46, the user can switch the tractor 1 from the manual travel mode to the automatic travel mode or from the automatic travel mode to the manual travel mode. It should be noted that the tractor 1 may be switched between the manual traveling mode and the automatic traveling mode by operating the monitor device 14 of the tractor 1 or a dedicated operation tool instead of the wireless communication terminal 46 . However, when the user instructs switching between the manual driving mode and the automatic driving mode, the switching is not unconditionally performed, and the switching is performed after other conditions are satisfied.

Specifically, as shown in FIG. 5, the tractor 1 of the present embodiment has a manual travel implementation mode, an autonomous travel preparation mode, a first autonomous travel implementation mode, a second autonomous travel implementation mode, a manual travel preparation mode, is set. Of these five travel modes, the tractor 1 performs manual travel in the manual travel execution mode and the autonomous travel preparation mode. In addition, the tractor 1 autonomously travels in the first autonomous travel implementation mode and the second autonomous travel implementation mode. In the manual travel preparation mode, the tractor 1 is stopped without performing manual travel or autonomous travel. Therefore, the manual travel execution mode and the autonomous travel preparation mode may be collectively referred to as the manual travel mode. Also, the first autonomous driving implementation mode and the second autonomous driving implementation mode may be collectively referred to as an automatic driving mode.

Note that the method of classifying the driving modes is an example, and any of the driving modes shown in FIG. 5 may be omitted. Moreover, driving modes other than the five shown in FIG. 5 may be included. For example, in order to shift from the autonomous driving preparation mode to the first autonomous driving execution mode, it is necessary to satisfy a plurality of conditions, and a state in which some of them are satisfied may be treated as another driving mode.

The manual travel implementation mode is a travel mode for causing the tractor 1 to perform manual travel. The autonomous driving preparation mode is a driving mode that the vehicle goes through before shifting from the manual driving execution mode to the autonomous driving mode. In the autonomous traveling preparation mode, the tractor 1 performs manual traveling because it is before switching to autonomous traveling.

The first autonomous travel implementation mode and the second autonomous travel implementation mode are travel modes for allowing the tractor 1 to travel autonomously. When transitioning from the autonomous driving preparation mode, the first autonomous driving execution mode is entered first. In the first autonomous traveling implementation mode, if a predetermined process (details of which will be described later) is not performed within a certain period of time, the vehicle shifts to the manual traveling implementation mode via the manual traveling preparation mode or the like. That is, it can be said that the first autonomous driving implementation mode is a limited-time (temporary) autonomous driving mode. On the other hand, in the second autonomous driving implementation mode, the driving mode is maintained unless an instruction to shift to the manual driving implementation mode or an operation clearly requesting manual driving is performed. Therefore, it can be said that the second autonomous driving implementation mode is a formal (original) autonomous driving mode. The manual driving preparation mode is a driving mode that may be passed through when shifting from the autonomous driving mode to the manual driving execution mode. In the manual travel preparation mode, as described above, the tractor 1 is stopped without performing manual travel or autonomous travel.

Next, transition conditions for each driving mode will be described in detail. Control for each running mode is performed by a running mode control section 4 b of the control section 4 .

First, the first mode transition condition, which is the condition for transitioning from the manual driving execution mode to the autonomous driving preparation mode, will be described. As shown in FIG. 3, a plurality of condition items are set in the first mode transition condition, but these are AND conditions, and when all of the plurality of condition items are satisfied, the autonomous driving preparation mode Transition. Specific condition items are (a) that the engine rotation speed is above a predetermined speed (for example, idling speed or above), and (b) that there is no abnormality in equipment (sensors, actuators, etc.). there is

Regarding the condition (a), the control unit 4 acquires the engine rotation speed based on the detection result of a sensor or the like that is attached to the engine 10 and outputs a pulse according to the rotation of the crankshaft, and determines whether or not it is equal to or higher than a predetermined speed. determine whether Regarding the condition (b), the control unit 4 determines an abnormality of the equipment based on the detection results of various sensors attached to the tractor 1 . It should be noted that abnormality of equipment may be determined for all equipment, but abnormality is determined only for equipment (position information acquisition unit 49, steering angle sensor 52, etc.) necessary for autonomous driving. good too.

Next, a second mode transition condition, which is a condition for transitioning from the autonomous driving preparation mode to the manual driving execution mode, will be described. As shown in FIG. 3, when the first mode transition condition is not satisfied, the driving mode transitions to the manual driving execution mode. That is, after satisfying the first mode transition condition and transitioning to the autonomous driving preparation mode, if the first mode transition condition is no longer satisfied afterward, the vehicle returns to the manual driving execution mode. The second mode transition condition is treated preferentially over the third mode transition condition. That is, if both the second mode transition condition and the third mode transition condition are satisfied, the second mode transition condition becomes more effective, and the manual running execution mode is entered.

Next, the third mode transition condition, which is the condition for transitioning from the autonomous driving preparation mode to the first autonomous driving execution mode, will be described. As shown in FIG. 3, a plurality of condition items are set in the third mode transition condition, but these are AND conditions, and when all of the plurality of condition items are satisfied, the first autonomous driving is executed. mode. Specific condition items are (a) that the forward/reverse switching lever 25 is positioned at the forward position or the neutral position, and (b) that none of the brake pedal 61, the clutch pedal 62, and the parking brake 26 is operated. , (c) the shift position is on the lower speed side than the predetermined speed, (d) the steering angle is within a predetermined angle, (e) the route on which autonomous travel is possible has been identified, and (f) autonomous travel. It is set that there is an instruction to start.

Regarding the conditions (a) to (c), the control unit 4 operates each operating device (forward/reverse switching lever 25, brake pedal 61, clutch pedal 62, parking brake 26, main shift lever 27, and auxiliary shift lever 19). The state is acquired and determined based on a sensor provided in each operation tool or an electric signal output by each operation tool. Here, conventionally, since it was possible to shift to the autonomous driving mode only when the forward/reverse switching lever 25 was in the neutral position, it was impossible to shift from the manual driving mode to the automatic driving mode unless the tractor 1 was stopped. On the other hand, in the present embodiment, the condition for shifting to the autonomous driving mode (first autonomous driving execution mode) is satisfied not only when the forward/reverse switching lever 25 is at the neutral position but also when it is at the forward position. In other words, when the forward/reverse switching lever 25 is in the reverse position, the condition for shifting to the autonomous driving mode is not satisfied). Therefore, the manual traveling mode can be shifted to the autonomous traveling mode without stopping the tractor 1 . In this case, since the mode is shifted to the autonomous driving mode while the forward/reverse switching lever 25 is in the forward position, there is a possibility that the tractor 1 may be driven without the user's intention when the mode is shifted to the manual driving mode. be. Therefore, the tractor 1 of this embodiment performs various processes in order to prevent the tractor 1 from traveling without the user's intention.

Regarding the condition (d), the control unit 4 acquires the steering angle based on the detection result of the steering angle sensor 52 and determines whether it is within a predetermined angle.

Regarding the condition (e), the control unit 4 performs the processing shown in FIG. 6 to determine whether or not there is a work route on which autonomous travel is possible. First, the control unit 4 (route processing unit 4c) communicates with the wireless communication terminal 46 to obtain a plurality of (for example, five) work routes P1 near the current position of the tractor 1 (S101). In FIG. 7, the work path P1 obtained by this process is indicated by a thick line. In addition, in order to appropriately switch between the manual travel mode and the autonomous travel mode, only the work route P1 (straight route) is acquired instead of the non-work route P2 (turning route) (candidate route for autonomous travel). do).

Next, the control unit 4 extracts a work path P1 that satisfies all of the following conditions from the acquired work paths P1 (S102). Condition (1) is that the distance between the work path P1 and the tractor 1 (distance L1 in FIG. 8) is within a predetermined range. Although the position of the positioning antenna 6 of the tractor 1 is used as a reference in the example shown in FIG. good too. Condition (2) is that the difference between the orientation of the work path P1 and the orientation of the tractor 1 (angle θ in FIG. 8) is within a predetermined range. Since the work path P1 and the tractor 1 both have directions, the angle θ is calculated in consideration of those directions. Condition (3) is that when the tractor 1 is in the work area, the distance to the non-work area (headland) (distance L2 shown in FIG. 8) is within a predetermined range. Condition (4) is that the distance to the working area (distance L3 shown in FIG. 8) is within a predetermined range when the tractor 1 is in the non-working area. Although the threshold value (predetermined value) for each condition is arbitrary, it is preferable that the threshold value of condition (1)<threshold value of condition (4)<threshold value of condition (3). For example, the threshold for condition (1) is 10 cm, the threshold for condition (2) is 10°, the threshold for condition (3) is 10 m, and the threshold for condition (4) is 10 m. Note that each threshold value may be ±50% of these values. The fifth condition is that the conditions (1) to (4) are continuously satisfied for a predetermined period of time.

The control unit 4 determines conditions (1) to (5) for all the work paths P1 acquired in step S101. Since the conditions (3) and (4) are not related to the work path P1, they do not have to be performed for each work path P1 (the determination is made only once for a specific work path P1). do it). Next, the control unit 4 determines whether or not the work path P1 that satisfies the above conditions has been extracted (S103). If the work path P1 that satisfies the above conditions is not extracted, the control unit 4 stores that there is no P1 that allows autonomous travel (S104). In this case, since the third mode transition condition is no longer satisfied, the transition to the first autonomous driving execution mode is not performed.

On the other hand, when the work path P1 that satisfies the above conditions is extracted, the control unit 4 determines whether or not a plurality of work paths P1 have been extracted (S105). If a plurality of work paths P1 are not extracted (that is, only one is extracted), the control unit 4 stores the extracted work path P1 as a route on which autonomous travel is possible (S106). When a plurality of work routes P1 are extracted, the control unit 4 stores the work route P1 closest to the start position of the travel route P among the plurality of work routes P1 as a route on which autonomous travel is possible (S107). For example, the work path P1 closest to the start position may be selected based on the smallness of at least one of the distance L1 to the tractor 1 and the angle θ of the orientation difference with the tractor 1 .

Regarding the condition (f) of the third mode transition condition, whether or not the control unit 4 instructs switching to autonomous traveling based on the operation performed by the user on the touch panel 39 of the wireless communication terminal 46 or the monitor device 14. judge.

Since it is necessary to satisfy the first mode transition condition and the third mode transition condition in order to shift from the manual driving mode to the automatic driving mode, the combination of these conditions corresponds to the autonomous driving start condition.

Next, a fourth mode transition condition, which is a condition for transitioning from the first autonomous driving implementation mode to the second autonomous driving implementation mode, will be described. The specific condition items are (a) that the forward/reverse switching lever 25 is positioned at the neutral position. That is, in the present embodiment, even if the forward/reverse switching lever 25 is in the forward position, it is possible to shift to the autonomous driving mode. , the vehicle is shifted to the second autonomous driving execution mode, which is the formal autonomous driving mode. As a result, it is possible to switch to autonomous traveling without stopping the tractor 1, and to prevent switching to manual traveling while the forward/reverse switching lever 25 is in the forward position. When the autonomous traveling preparation mode is shifted to the first autonomous traveling implementation mode, if the forward/reverse switching lever 25 is positioned at the neutral position, the second autonomous traveling implementation mode is immediately changed from the first autonomous traveling implementation mode. transition to In addition, in the first autonomous traveling implementation mode and the second autonomous traveling implementation mode, the traveling of the tractor 1 is controlled regardless of the position of the forward/reverse switching lever 25, and even if the fourth mode transition condition is satisfied, that is, , the tractor 1 does not stop even if the forward/reverse switching lever 25 is set to the neutral position, and continues to travel autonomously along a predetermined route.

Next, a fifth mode transition condition, which is a condition for transitioning from the first autonomous driving execution mode to the manual driving execution mode, will be described. As specific condition items, (a) the forward/reverse switching lever 25 is set at the reverse position. Since the forward/reverse switching lever 25 is positioned at the forward position or the neutral position when the first autonomous driving mode is entered, condition (a) is not satisfied unless the user operates the forward/reverse switching lever 25 . Therefore, when the condition (a) is satisfied, the user's intention to return to manual driving is clear, so the mode is shifted to the manual driving implementation mode (the autonomous driving mode is ended).

Next, a sixth mode transition condition, which is a condition for transitioning from the first autonomous driving execution mode to the manual driving preparation mode, will be described. As shown in FIG. 3, a plurality of condition items are set in the sixth mode transition condition, but these are OR conditions, and when at least one condition item is satisfied, the transition to the manual travel preparation mode is made. do. Specific condition items are (a) that the first mode transition condition is not satisfied, (b) that any one of the brake pedal 61, the clutch pedal 62, the parking brake 26, and the steering handle 12 is operated, and (c) (d) the distance to the route and the difference in direction from the route are greater than or equal to a predetermined value; (e) an instruction to start manual travel is issued; is set. The sixth mode transition condition is treated preferentially over the fourth and fifth mode transition conditions. In other words, even if the fourth or fifth mode transition condition is satisfied, if the sixth mode transition condition is satisfied, the manual travel preparation mode is entered.

The determination method for the conditions (a) to (c) is the same as described above, so the description is omitted. Condition (c) is a condition item for preventing the autonomous traveling mode from continuing while the forward/reverse switching lever 25 is in the forward position. The predetermined time of condition (c) is, for example, 5 seconds, but may be any value between 3 seconds and 30 seconds. In addition, in the fifth mode transition condition, when the forward/reverse switching lever 25 is operated, the user's intention to return to manual driving is clear, so the manual driving mode is selected. The user's intention to return to manual driving is not clear just by operating the brake pedal 61, clutch pedal 62, parking brake 26, and steering handle 12). Therefore, the mode is shifted to the manual run preparation mode.

In condition (d), the distance to the route is the distance between the work route P1 and the tractor 1. Also, the difference in direction from the path is the angle formed by the work path P1 and the tractor 1 . Condition (d) is satisfied when these values exceed predetermined values.

In condition (e), the control unit 4 determines whether or not an instruction to switch to manual driving is given based on the user's operation on the touch panel 39 of the wireless communication terminal 46 or the monitor device 14 .

Next, the seventh mode transition condition, which is the condition for transitioning from the first autonomous driving execution mode to the manual driving execution mode, will be described. As specific condition items, it is set that (a) the forward/reverse switching lever 25 is positioned at the forward position or the reverse position. Since the forward/reverse switching lever 25 is positioned at the neutral position when the vehicle is shifted to the second autonomous running mode, condition (a) is not satisfied unless the user operates the forward/reverse switching lever 25 . Therefore, when the condition (a) is satisfied, the user's intention to return to manual running is clear, so the mode is shifted to the manual running execution mode.

Next, conditions for shifting from the second autonomous driving implementation mode to the manual driving preparation mode will be described. This condition is the same as the condition for shifting from the first autonomous driving execution mode to the manual driving preparation mode. In the second autonomous running mode, when the forward/reverse switching lever 25 is moved to the forward position, the manual running mode is entered. Therefore, condition (c) of the sixth mode transition condition is not satisfied. Moreover, the sixth mode transition condition is treated preferentially over the seventh mode transition condition, similarly to the first autonomous driving execution mode.

Next, the eighth mode transition condition, which is the condition for transitioning from the manual travel preparation mode to the manual travel implementation mode, will be described. As shown in FIG. 3, a plurality of condition items are set in the eighth mode transition condition. Transition. Specific condition items are set such that (a) the forward/reverse switching lever 25 is positioned at the neutral position, and (b) the vehicle speed is equal to or less than a predetermined value. By providing condition (a), it is possible to prevent switching to manual travel while the forward/reverse switching lever 25 is in the forward position. Further, the control unit 4 determines the condition (b) based on the detection result of the vehicle speed sensor 53 .

Thus, after shifting to the manual driving preparation mode, it is not possible to directly shift to the first autonomous driving execution mode or the second autonomous driving execution mode. Therefore, in the first autonomous driving implementation mode or the second autonomous driving implementation mode, when the sixth mode transition condition is satisfied, the autonomous driving mode ends, and then the manual driving mode is entered.

In the present embodiment, manual travel can be switched to autonomous travel while the forward/reverse switching lever 25 is positioned at the forward position, so switching to autonomous travel can be performed without stopping the tractor 1. In addition, in order to prevent switching to manual travel while the forward/reverse switching lever 25 is in the forward position, condition (a) of the fourth mode transition condition, condition (a) of the eighth mode transition condition, etc. is provided. As a result, it is possible to prevent the tractor 1 from running against the user's intention even when the mode is switched to manual running.

As described above, the control unit 4 of the tractor 1 of this embodiment includes the forward/reverse control unit 4a and the traveling mode control unit 4b. The forward/rearward movement control unit 4a controls the forward/backward movement of the tractor 1 . The traveling mode control unit 4b is a manual driving mode in which the tractor 1 is moved forward and backward according to the operation of the operating tools (for example, the brake pedal 61, the accelerator pedal 63, the sub-transmission lever 19, the main transmission lever 27, etc.) provided to the tractor 1. One running mode is executed from a plurality of running modes including at least a running mode and an autonomous running mode in which forward and backward movement of the tractor 1 is controlled without depending on the operation of the operating tool. The traveling mode control unit 4b executes the autonomous traveling mode by satisfying the autonomous traveling start conditions (the first mode transition condition and the third mode transition condition). A forward/reverse switching lever 25 provided in the tractor 1 can be switched between at least a forward position, a neutral position, and a reverse position. When the forward/reverse switching lever 25 is in the forward position, it is possible to satisfy the autonomous travel start condition.

As a result, even when the forward/reverse switching lever 25 is in the forward position, the conditions for starting autonomous travel are satisfied, so that the tractor 1 can be shifted from manual travel to autonomous travel without stopping. Therefore, switching from manual running to autonomous running can be performed smoothly.

Further, in the control unit 4 of the tractor 1 of the present embodiment, the traveling mode control unit 4b executes the autonomous traveling mode when the autonomous traveling mode is executed with the forward/reverse switching lever 25 positioned at the forward position. After that, when the forward/reverse switching lever 25 is not changed to the neutral position before the predetermined time elapses, the autonomous driving mode is terminated (shifting to the manual driving execution mode via the manual driving preparation mode).

As a result, it is possible to prevent the autonomous traveling mode from continuing while the forward/reverse switching lever 25 is in the forward position, so that when returning to manual traveling again, the tractor 1 moves regardless of the operator's intention. can be prevented.

Further, in the control unit 4 of the tractor 1 of the present embodiment, if the forward/reverse switching lever 25 is changed to the neutral position before the predetermined time elapses, the forward/reverse switching lever 25 is moved from the neutral position to a position other than the neutral position. Execute manual drive mode when changed. If the forward/reverse switching lever 25 is not changed to the neutral position before the predetermined time elapses, (the manual traveling preparation mode is entered, and in this manual traveling preparation mode), the forward/reverse switching lever 25 is changed to the neutral position. Execute manual drive mode.

As a result, when the forward/reverse switching lever 25 is changed from the neutral position to another position, it is possible to shift to the manual traveling because the intention to change to the manual traveling is clear. On the other hand, if the forward/reverse switching lever 25 is not changed to the neutral position within the predetermined time, the tractor 1 may move irrespective of the operator's intention when the manual travel is selected. After changing the switching lever 25 to the neutral position, it shifts to the manual running mode.

In addition, in the control unit 4 of the tractor 1 of the present embodiment, the traveling mode control unit 4b controls at least one of the steering handle 12, the brake pedal 61, and the parking brake 26 provided to the tractor 1 after a predetermined period of time has elapsed. is operated, the manual travel mode is executed after the forward/reverse switching lever 25 is changed to the neutral position (in the manual travel preparation mode).

As a result, the operation of the forward/reverse switching lever 25 clearly indicates the intention of switching to manual driving, but the operation of the steering handle 12, the brake pedal 61, and the parking brake 26 does not clearly indicate the intention of switching to manual driving. Therefore, by shifting to the manual travel mode after the forward/reverse switching lever 25 is changed to the neutral position, mode switching in consideration of the operator's intention is realized.

Further, the control unit 4 of the tractor 1 of this embodiment can acquire the position information of the tractor 1 from the position information acquisition unit 49 that acquires the position information of the tractor 1 . The tractor 1 includes a route processing unit 4c that performs processing for generating or acquiring a travel route including a plurality of work routes and a plurality of non-work routes. The autonomous travel start condition includes that a work route on which the tractor 1 can travel autonomously has been specified based on the current position information of the tractor 1 and the travel route.

As a result, the mode is shifted to the autonomous driving mode only when there is a route on which autonomous driving is possible, so rational processing is performed.

Although the preferred embodiments of the present invention have been described above, the above configuration can be modified, for example, as follows.

The condition items of various conditions described in the above embodiments are examples, and at least one condition item may be added, deleted, or changed. For example, in the present embodiment, it is assumed that the manual driving mode is switched to the autonomous driving mode while the user is on the tractor 1. Therefore, it is assumed that the user is on the tractor 1 as the first mode transition condition. May be included in condition items. The fact that the user is on the tractor 1 can be detected by a load sensor or the like provided on the seat 13, for example.

Further, in the above-described embodiment, the sixth mode transition condition includes that the first mode transition condition is not satisfied, and the transition condition from the manual driving execution mode to the autonomous driving preparation mode and the first or second autonomous driving mode. Although the conditions for transition from the traveling implementation mode to the manual traveling preparation mode are partly common conditions, both may be different conditions. That is, the transition condition from the manual driving execution mode to the autonomous driving preparation mode is a condition for permitting autonomous driving (autonomous driving permission condition), while the transition condition from the first or second autonomous driving execution mode to the manual driving preparation mode is may be a condition for prohibiting autonomous driving (autonomous driving prohibition condition). In that case, for example, when the tractor 1 is equipped with a load sensor as described above, the autonomous travel permission condition includes that the load sensor is ON, while the autonomous travel prohibition condition includes that the load sensor is ON. It may not be included. This is because the user's body may float due to vibrations of the tractor 1 or the like, and the load sensor may be temporarily turned off. However, if the load sensor is OFF for a predetermined period of time (for example, 5 seconds), it may be determined that the user has gotten off the tractor 1, and the manual travel preparation mode may be entered.

Further, in the above embodiment, when the forward/reverse switching lever 25 is positioned at the forward position and the mode is shifted to the first autonomous driving mode, the forward/reverse switching lever 25 is changed to the neutral position after the predetermined time has elapsed. When it is turned on, it shifts to the manual running mode via the manual running preparation mode. Alternatively, the autonomous driving mode may be maintained when the forward/reverse switching lever 25 is changed to the neutral position after a predetermined period of time has elapsed. In addition, in the first autonomous traveling implementation mode or the second autonomous traveling implementation mode, when there is some abnormality (for example, detection of non-boarding of the user), when the abnormality is resolved early, the first autonomous traveling implementation mode Alternatively, it may be configured to return to the second autonomous driving implementation mode.

Further, in the above embodiment, when the mode is shifted from the first autonomous driving mode or the second autonomous driving mode to the manual driving preparation mode, the mode is shifted to the manual driving mode when the eighth mode transition condition is satisfied. However, under certain conditions, the manual running preparation mode may be changed to the second autonomous running execution mode when the ninth mode transition condition is satisfied. Here, the specific condition means that in the second autonomous driving mode, among the sixth mode transition conditions, the above condition (c) (any of the brake pedal 61, the clutch pedal 62, the parking brake 26, and the steering handle 12 is operated), and the manual running preparation mode is entered. Further, the ninth mode transition condition is that the forward/reverse switching lever 25 is in the neutral position, and an instruction to resume autonomous travel is issued based on the operation of the touch panel 39 of the wireless communication terminal 46 .

In the above embodiment, the lever-shaped forward/reverse switching lever 25 was described as an example of the forward/reverse switching operation tool. Further, the forward/reverse switching lever 25 can be switched between the forward position, the reverse position, and the neutral position, but may be switched to another position. Further, the forward/reverse switching lever 25 is an operating tool for instructing switching between forward and backward travel, but may be an operating tool capable of instructing both shifting and switching between forward and reverse travel. In this case, there are a plurality of forward positions, but it may be possible to switch to the autonomous traveling mode only when the vehicle is positioned at the low-speed side forward position, or when all the forward positions are positioned. , it may be possible to switch to the autonomous driving mode.

In the above embodiment, the travel route acquisition unit 35 of the wireless communication terminal 46 generates a travel route, and the route processing unit 4c of the control unit 4 acquires a part or all of the route. 4c may generate the travel route. Moreover, the monitor device 14 provided in the tractor 1 may generate the travel route instead of the wireless communication terminal 46 .

1 tractor (work vehicle)
4 control unit (work vehicle control device)
4a forward/reverse control unit 4b running mode control unit 4c route processing unit 25 forward/reverse switching lever (forward/backward switching operation tool)

Claims (3)

A work vehicle control device capable of autonomously traveling a work vehicle along a travel route,
A plurality of modes including at least a manual travel mode in which the work vehicle travels according to the operation of the operation tool provided on the work vehicle, and an autonomous travel mode in which the work vehicle travels are controlled without depending on the operation of the operation tool. a running mode control unit that executes one running mode from the running modes of
The autonomous driving mode includes a first autonomous driving execution mode in which a transition to the manual driving mode is performed if a predetermined process is not performed within a certain period of time, and an instruction to shift to the manual driving mode or unless a specific operation is performed. and a second autonomous driving implementation mode that maintains the autonomous driving mode ,
The driving mode control unit satisfies an autonomous driving start condition to execute the first autonomous driving execution mode,
The running mode control unit shifts from the first autonomous running implementation mode to the second autonomous running implementation mode in response to a predetermined operation of the operating tool.
Work vehicle controller. The work vehicle control device according to claim 1,
The traveling mode control unit shifts to the second autonomous traveling implementation mode when a predetermined operation of the operation tool is performed before a certain period of time has elapsed after the first autonomous traveling implementation mode is started.
Work vehicle controller. The work vehicle control device according to claim 2 ,
The running mode control unit terminates the autonomous running mode when the predetermined time elapses without a predetermined operation of the operation tool being performed .
Work vehicle controller.

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