JP7827779B2 - Tractor - Google Patents

Description

The present invention relates to a tractor.

An example of such a work vehicle (tractor) is described in Patent Document 1 below. The work vehicle described in this document is equipped with an obstacle detection means at the front of the vehicle body that can detect obstacles ahead of the vehicle body. When an obstacle is detected by the obstacle detection means, this work vehicle stops automatic driving (autonomous travel) of the vehicle body, thereby preventing the vehicle body from coming into contact with the obstacle ahead of the vehicle body.

JP 2008-92818 A

However, with the above-mentioned conventional technology, the obstacle detection means can only detect obstacles located in front of the vehicle body, and cannot detect obstacles located behind the vehicle body, which means there is a possibility that the obstacle may come into contact with work equipment or the like located behind the vehicle body.

In light of the above situation, it is desirable to be able to appropriately prevent the vehicle body from coming into contact with obstacles.

The tractor of the present invention comprises a vehicle body and
a lifting device capable of attaching a working device to the vehicle body;
a cabin provided in the vehicle body;
a hood provided at the front side of the cabin;
an obstacle detector and an obstacle probe;
A tractor comprising:
The obstacle detector is provided at the rear of the cabin to detect the area behind the lifting device, and side obstacle detectors, which are obstacle detectors , are provided to the outside of the cabin door in the left-right direction of the vehicle body , and multiple front obstacle detectors, which are obstacle detectors, are provided at the front of the hood.
In the present invention, it is preferable that the obstacle detector provided in the cabin is provided below the roof of the cabin.
In the present invention, it is preferable that the side obstacle detector is provided on a rear fender on the side of the cabin.
In the present invention, it is preferable that a second obstacle detector is provided, the second obstacle detector having a detection target area that at least partially overlaps with the detection target areas of the plurality of front obstacle detectors.
It is preferable that the first obstacle detector is attached to the rear of the rear fender.
Further, the work vehicle of the present invention is
The vehicle is equipped with an electronic control system for autonomous driving,
the electronic control system is provided with an obstacle detection module that detects the presence or absence of an obstacle, and a travel suppression control unit that suppresses travel of the vehicle body when the obstacle detection module detects the obstacle,
The obstacle detection module detects the obstacles having a height equal to or greater than a predetermined height.
The work vehicle of the present invention is equipped with an electronic control system for automatic driving that automatically drives the vehicle body, and the electronic control system is equipped with an obstacle detection module that detects the presence or absence of obstacles, and a driving suppression control unit that suppresses the driving of the vehicle body when the obstacle detection module detects an obstacle, and the obstacle detection module is equipped with an obstacle detector that detects obstacles present in an area to be explored, and an obstacle detector that detects obstacles present in a detection area that is at least partially different from the area to be explored.
Further, the work vehicle of the present invention is
The vehicle is equipped with an electronic control system for autonomous driving,
the electronic control system is provided with an obstacle detection module that detects the presence or absence of an obstacle, and a travel suppression control unit that suppresses travel of the vehicle body when the obstacle detection module detects an obstacle,
The obstacle detection module is provided with a plurality of obstacle detectors that detect obstacles present in an area to be explored;
The obstacle detectors include a pair of first obstacle detectors on the left and right sides, each of which has a target area to be detected on the sides of the rear end of the main body of the vehicle.

According to the present invention, a pair of left and right first obstacle detectors can detect obstacles present near the rear end of the main body of the vehicle. When an obstacle is detected by the pair of left and right first obstacle detectors, the vehicle's movement is restricted. This makes it possible to prevent the vehicle from transitioning from a stopped state to a moving state when, for example, an obstacle exists between the work equipment located at the rear end of the vehicle and the main body of the vehicle. This avoids inconveniences such as the work equipment running over an obstacle, and improves the reliability of autonomous driving.

In this way, the present invention makes it possible to avoid the rear of the vehicle coming into contact with obstacles.

In the present invention,
It is preferable that the first obstacle detector is attached to the rear of the rear fender.

With the above configuration, the first obstacle detector can accurately detect obstacles located near the rear ends of the rear wheels below the rear fender.

In the present invention,
It is preferable that the obstacle detectors include a pair of second obstacle detectors on the left and right, each of which has a target area to be searched, the side of the center of the front and rear of the vehicle body.

With the above configuration, the second obstacle detector can accurately detect obstacles located to the sides of the center of the front and rear of the vehicle body.

In the present invention,
It is preferable that the second obstacle detector is attached to the front of the rear fender.

With the above configuration, the second obstacle detector can accurately detect obstacles located near the front ends of the rear wheels below the rear fender.

In the present invention,
The obstacle detection module is provided with an obstacle detector that detects obstacles present in a detection target area using a detection method different from that of the obstacle detector,
It is preferable that the search target area of the obstacle detector includes an area located below the detection target area of the obstacle detector.

With the above configuration, the area below the obstacle detector's detection target area is covered by the obstacle detector's detection target area, reducing blind spots where obstacles cannot be detected and making it possible to detect all obstacles around the vehicle that could interfere with autonomous driving.

In the present invention,
Preferably, the obstacle detector is an ultrasonic sonar.

With the above configuration, relatively inexpensive ultrasonic sonar can be used to detect obstacles, thereby minimizing overall cost increases.

FIG. 2 is a left side view of the tractor showing the arrangement of the obstacle detector and obstacle detectors. FIG. 2 is a top view of the tractor showing the arrangement of obstacle detectors and other obstacle detectors. FIG. 2 is a perspective view of a tractor showing the arrangement of obstacle detectors and other obstacle detectors. FIG. 2 is a block diagram showing a schematic configuration of a control system. 10 is a schematic diagram of a left side view showing an area to be searched by an obstacle detector and an area to be detected by an obstacle detector. FIG. 1 is a schematic diagram of a top view showing an area to be searched by an obstacle detector and an area to be detected by an obstacle detector. FIG. 2 is a front view schematic diagram showing a detection target area by an obstacle detector.

An embodiment of the present invention will now be described with reference to the drawings. Note that the arrow indicated by the symbol F in Figures 1 and 2 indicates "front," the arrow indicated by the symbol U in Figure 1 indicates "up," and the arrow indicated by the symbol R in Figures 1 and 2 indicates "right."

As shown in Figures 1 to 3, a tractor (an example of a "work vehicle") is equipped with a body frame 1 spanning the front and rear ends of the body, left and right traveling devices 2 located on the left and right sides of the body frame 1, a motor unit 3 located on the front side of the body frame 1, a cabin 4 located on the rear side of the body frame 1, and a three-point linkage mechanism 5 for connecting a work device W (see Figures 5 and 6) attached to the rear end of the body frame 1 so that it can be raised and lowered and swung. As shown in Figures 1 and 2, a weight 1A is attached to the front end of the body frame 1.

As shown in Figures 1 to 3, the body frame 1 is equipped with a front frame 7 that extends forward from the lower part of the engine 6 located in the power unit 3, and a case unit 8 that also serves as a rear frame that extends rearward from the lower rear end of the engine 6. Although not shown, the case unit 8 is equipped inside with a pedal-operated main clutch that interrupts the power from the engine 6, a speed-change transmission unit that splits the power that passes through the main clutch into power for driving and power for working and changes the speed, and left and right side brakes that act on the left and right traveling devices 2.

As shown in Figures 1 to 3, the left and right traveling devices 2 are equipped with left and right front wheels 9 that function as drivable steering wheels, and left and right rear wheels 10 that function as drive wheels. The left and right front wheels 9 are drivably supported in a steerable state at the left and right ends of wheel support members 11 that are supported in a rolling manner on the front frame 7. The wheel support members 11 are front axle cases that house transmission shafts for front-wheel drive. The left and right rear wheels 10 are drivably supported by case units 8, and the upper sides of each rear wheel 10 are covered by left and right rear fenders 12 located on the rear side of the vehicle body.

As shown in Figures 1 to 3, the power unit 3 includes a water-cooled engine 6 located at the rear of the power unit 3, downstream of the power unit 3 in the cooling direction; a cooling fan 13 located at the front of the vehicle, upstream of the engine 6 in the cooling direction; a radiator 14 located further forward of the cooling fan 13; a battery (not shown) located further forward of the radiator 14; an exhaust treatment device (not shown) located above the rear of the engine 6; an air cleaner (not shown) located above the front of the engine 6; and a swing-open hood 16 that covers the engine 6, radiator 14, and other components from above. The engine 6 is an electronically controlled diesel engine equipped with a common rail system. The exhaust treatment device is equipped with a DOC (Diesel Oxidation Catalyst), a DPF (Diesel Particulate Filter), and other components.

As shown in Figures 1 to 3, the cabin 4 forms a driver's section 17 and a passenger space at the rear of the vehicle body. The driver's section 17 is equipped with a clutch pedal 18 that enables operation of the main clutch, left and right brake pedals (not shown) that enable operation of the left and right side brakes, a manual steering wheel 19 that enables manual steering of the left and right front wheels 9, a shuttle lever 20 for switching between forward and reverse, a driver's seat 22 with an armrest 21 for the right arm, and a display unit 23 that has a touch-operable LCD panel or the like. The steering wheel 19 is connected to the left and right front wheels 9 via a steering mechanism 25 that has a fully hydraulic power steering unit (hereinafter referred to as a PS unit 24). The armrest 21 is equipped with a main gearshift lever 26 (see Figure 4), a lift lever 27 (see Figure 4) that sets the height position of the work implement W, and a lift switch 28 (see Figure 4) that commands the lifting and lowering of the work implement W.

The three-point linkage mechanism 5 shown in Figures 1 to 3, etc., is driven to swing up and down by the operation of an electro-hydraulic controlled lifting drive unit 29 mounted on the vehicle body, as shown in Figure 4. As shown in Figures 5 and 6, various types of work implements W, such as rotary tillers, plows, disc harrows, cultivators, subsoiler, seed sowing devices, and spraying devices, can be connected to the three-point linkage mechanism 5. When the work implement W connected to the three-point linkage mechanism 5 is a rotary tiller or the like driven by power from the vehicle body, the work power extracted from the transmission unit is transmitted to the work implement W via an external transmission shaft.

As shown in FIG. 4, the vehicle body is equipped with a main electronic control unit (hereinafter referred to as the main ECU 30) and an engine electronic control unit (hereinafter referred to as the engine ECU 31). The main ECU 30 is communicatively connected to the aforementioned electrohydraulic lift drive unit 29, the engine electronic control unit (hereinafter referred to as the engine ECU 31), the electronically controlled main transmission 32, forward/reverse switching device 33, and PTO clutch 34 provided in the speed change transmission unit, the electrohydraulic brake operation unit 35 that enables automatic operation of the left and right side brakes, and the in-vehicle information acquisition unit 36 that acquires in-vehicle information including vehicle speed, via an in-vehicle LAN such as a CAN (Controller Area Network) or a communication line. The main ECU 30 and engine ECU 31 are equipped with microprocessors having CPUs, EEPROMs, etc. The main ECU 30 is equipped with a driving control unit 30A that controls the driving of the vehicle body, and a work control unit 30B that controls the work implement W.

The main transmission 32 uses a hydrostatic continuously variable transmission that continuously changes the speed of the traveling power. The forward/reverse switching device 33 also serves as a traveling clutch that connects and disconnects the traveling power. Although not shown, the speed change transmission unit is equipped with not only the main transmission 32, but also an auxiliary transmission that continuously changes the speed of the traveling power, and a PTO transmission that continuously changes the speed of the working power, etc.

As shown in FIG. 4, the in-vehicle information acquisition unit 36 includes various sensors and switches, such as a rotation sensor 37 that detects the output rotation speed of the engine 6, a vehicle speed sensor 38 that detects the output rotation speed of the auxiliary transmission as the vehicle speed, a first lever sensor 39 that detects the operating position of the main shift lever 26, a second lever sensor 41 that detects the operating position of the auxiliary shift lever 40 provided in the driver's unit 17, a third lever sensor 42 that detects the operating position of the shuttle lever 20, a fourth lever sensor 43 that detects the operating position of the lift lever 27, the aforementioned lift switch 28, a swing lift switch 44, a reverse lift switch 45, and a PTO switch 46 provided in the driver's unit 17, a height sensor 47 that detects the vertical swing angle of the left and right lift arms (not shown) of the lift drive unit 29 as the height position of the work implement W, and a steering angle sensor 48 that detects the steering angle of the front wheels 9.

The cruise control unit 30A has various control programs and the like that enable control of the vehicle's travel. Based on the output of the rotation sensor 37, the output of the vehicle speed sensor 38, the output of the first lever sensor 39, and the output of the second lever sensor 41, the cruise control unit 30A performs vehicle speed control by manipulating the trunnion shaft (not shown) of the main transmission 32 so that the vehicle speed reaches a control target vehicle speed calculated from the engine speed and the operating positions of the main shift lever 26 and the sub-shift lever 40. This allows the driver to change the vehicle speed to any desired speed by operating the main shift lever 26 to any operating position.

The driving control unit 30A performs forward/reverse switching control, switching the forward/reverse switching device 33 to a transmission state that corresponds to the operating position of the shuttle lever 20, based on the output of the third lever sensor 42. This allows the driver to set the vehicle's traveling direction forward by operating the shuttle lever 20 to the forward position. The driver can set the vehicle's traveling direction reverse by operating the shuttle lever 20 to the reverse position.

The work control unit 30B has various control programs and the like that enable control of the work device W. Based on the output of the fourth lever sensor 43 and the output of the height sensor 47, the work control unit 30B performs position control that controls the operation of the lift drive unit 29 so that the work device W is positioned at a height that corresponds to the operating position of the lift lever 27. This allows the driver to change the height position of the work device W to any height position by operating the lift lever 27 to any operating position.

When the lift switch 28 is manually operated to switch it to a lift command state, the work control unit 30B performs lift control, which controls the operation of the lift drive unit 29 so that the work implement W rises to a preset upper limit position, based on the lift command from the lift switch 28 and the output of the height sensor 47. This allows the driver to automatically raise the work implement W to the upper limit position by switching the lift switch 28 to a lift command state.

When the lift switch 28 is manually operated to switch it to a lowering command state, the work control unit 30B performs lowering control, which controls the operation of the lift drive unit 29 so that the work implement W is lowered to the working height position set by the lift lever 27, based on the lowering command from the lift switch 28, the output of the fourth lever sensor 43, and the output of the height sensor 47. This allows the driver to automatically lower the work implement W to the working height position by switching the lift switch 28 to a lowering command state.

When the execution of the turn-linked lift control is selected by manually operating the turn lift switch 44, the work control unit 30B automatically performs the lift control described above when it detects, based on the output of the steering angle sensor 48 that detects the steering angle of the front wheels 9, that the steering angle of the front wheels 9 has reached the set angle for turning along the edge of a field. This allows the driver to automatically lift the work implement W to its upper limit position in conjunction with the start of a turning along the edge of a field by selecting the execution of the turn-linked lift control.

When the reverse-linked lift control is selected by manually operating the reverse lift switch 45, the work control unit 30B automatically performs the lift control described above when it detects manual operation of the shuttle lever 20 to the reverse position based on the output of the third lever sensor 42. As a result, by selecting to execute the reverse-linked lift control, the driver can automatically lift the work implement W to its upper limit position in conjunction with switching to reverse travel.

When the PTO switch 46 is manually switched to the ON position, the work control unit 30B performs clutch engagement control to switch the PTO clutch 34 to the ON state so that work power is transmitted to the work implement W, based on the switch to the ON position. This allows the driver to operate the work implement W by operating the PTO switch 46 to the ON position.

When the PTO switch 46 is manually switched to the OFF position, the work control unit 30B performs clutch disengagement control, which switches the PTO clutch 34 to the OFF state based on the switch to the OFF position, so that work power is not transmitted to the work implement W. This allows the driver to stop the work implement W by operating the PTO switch 46 to the OFF position.

When the PTO switch 46 is manually operated to switch its operating position to the automatic position, the work control unit 30B automatically performs the clutch disengagement control described above in conjunction with the execution of the ascent control described above, and automatically performs the clutch engagement control described above in conjunction with the execution of the descent control described above. This allows the driver to stop the work implement W in conjunction with the automatic ascent of the work implement W to its upper limit position, and to operate the work implement W in conjunction with the automatic descent of the work implement W to the working height position, by operating the PTO switch 46 to the automatic position.

As shown in Figure 4, this tractor is equipped with a selection switch 50 that allows selection of a driving mode such as manual driving mode or automatic driving mode, and an automatic driving electronic control system 51 that automatically drives the vehicle when automatic driving mode is selected. The electronic control system 51 is equipped with the main ECU 30 mentioned above, an automatic steering unit 52 that enables automatic steering of the left and right front wheels 9, a positioning unit 53 that measures the position and orientation of the vehicle, and a monitoring unit 54 that monitors the area around the vehicle.

As shown in Figures 2 to 4, the automatic steering unit 52 is composed of the PS unit 24 described above. When manual driving mode is selected, the PS unit 24 steers the left and right front wheels 9 based on the rotation of the steering wheel 19. When automatic driving mode is selected, the PS unit 24 steers the left and right front wheels 9 based on control commands from the main ECU 30.

In other words, the left and right front wheels 9 can be steered automatically without the need for a dedicated steering unit for automatic steering. Furthermore, if a malfunction occurs in the electrical system of the PS unit 24, the driver can easily switch to manual steering, allowing the vehicle to continue being driven.

As shown in Figures 1 to 4, the positioning unit 53 is equipped with a satellite navigation device 60 that measures the position and orientation of the vehicle using the well-known Global Positioning System (GPS), an example of the Global Navigation Satellite System (GNSS). Positioning methods that use GPS include Differential GPS (DGPS) and Real-Time Kinematic GPS (RTK-GPS), but this embodiment uses RTK-GPS, which is suitable for positioning moving objects.

The satellite navigation device 60 is equipped with a satellite navigation antenna unit 61 that receives radio waves transmitted from GPS satellites (not shown) and positioning data transmitted from a reference station (not shown) installed at a known location. The reference station transmits the positioning data obtained by receiving the radio waves from the GPS satellites to the satellite navigation device 60. The satellite navigation device 60 determines the position and orientation of the vehicle based on the positioning data obtained by receiving the radio waves from the GPS satellites and the positioning data from the reference station.

The antenna unit 61 is attached to the roof 62 of the cabin 4, located at the top of the vehicle body, to increase the reception sensitivity of radio waves from GPS satellites. Therefore, the position and orientation of the vehicle measured using GPS includes positioning errors caused by misalignment of the antenna unit 61 due to yawing, pitching, or rolling of the vehicle body.

To enable correction to eliminate the above-mentioned positioning errors, the vehicle body is equipped with an inertial measurement unit (IMU) 63, which has a three-axis gyroscope (not shown) and a three-directional acceleration sensor (not shown) and measures the yaw angle, pitch angle, roll angle, etc. of the vehicle body. The inertial measurement unit 63 is provided inside the antenna unit 61 to make it easier to determine the amount of positional misalignment of the antenna unit 61 mentioned above. The antenna unit 61 is attached to the left-right center of the front upper surface of the roof 62 of the cabin 4 so that it is located at the center of the tread T of the vehicle body and the center of the wheelbase L when viewed from above (see Figure 2).

As shown in FIG. 4, the main ECU 30 is equipped with an automatic driving control unit 30C having various control programs, etc. that enable the vehicle to drive automatically. The automatic driving control unit 30C transmits various control commands to the driving control unit 30A, the work control unit 30B, etc. at appropriate times based on the target driving route and the positioning results of the positioning unit 53, etc., so that the vehicle automatically drives along a predetermined target driving route in the field at a set speed while performing work appropriately. The driving control unit 30A transmits various control commands to the main transmission 32, the forward/reverse switching device 33, etc. at appropriate times based on the various control commands from the automatic driving control unit 30C and the various acquired information from the in-vehicle information acquisition unit 36, etc., to control the operation of the main transmission 32, the forward/reverse switching device 33, etc. The work control unit 30B controls the operation of the lift drive unit 29, PTO clutch 34, etc. by sending various control commands at appropriate times to the lift drive unit 29, PTO clutch 34, etc. based on various control commands from the automatic driving control unit 30C and various acquired information from the in-vehicle information acquisition unit 36.

As shown in Figures 1 to 4, the monitoring unit 54 is equipped with an obstacle detection module 64 that detects the presence or absence of an obstacle, a driving suppression control unit 30D that performs driving suppression control (contact avoidance control that avoids contact with the obstacle) to suppress the vehicle's driving when the obstacle detection module 64 detects an obstacle, four monitoring cameras 66 that capture images of the area around the vehicle, and an image processing device 67 that processes images captured by the monitoring cameras 66.

The obstacle detection module 64 shown in FIG. 4 is equipped with multiple obstacle detectors 65 that detect obstacles present in the detection target area Y, multiple obstacle probes 68 that detect obstacles present in the detection target area X, and two detection information processing devices 69 that perform a determination process to determine whether an obstacle has approached within close range of the vehicle body based on the detection information from each obstacle probe 68. The obstacle detectors 65 detect the approach of an obstacle within close range (e.g., within 10 m) of the vehicle body. Each obstacle probe 68 detects the presence or absence of an obstacle within close range (e.g., within 1 m) of the vehicle body. In other words, the obstacle detection module 64 is equipped with obstacle detectors 65 that detect obstacles present in the detection target area X using a detection method different from that of the obstacle probes 68.

Figures 5 to 7 schematically show the detection target area X of the obstacle detector 65 and the search target area Y of the obstacle detector 68. The search target area Y of the obstacle detector 68 includes an area located below the detection target area X of the obstacle detector 65. Note that for convenience of illustration, the detection target area X and the search target area Y are omitted to some extent in Figures 5 to 7.

The detection target area X and the exploration target area Y shown in Figures 5 to 7 each change depending on the vehicle speed. Specifically, the detection target area X and the exploration target area Y each become larger as the vehicle speed increases.

Each obstacle detector 68 employs ultrasonic sonar, an example of a distance measurement sensor that uses ultrasonic waves for distance measurement. The eight obstacle detectors 68 are distributed around the front end and both left and right ends of the vehicle body so that the front and both left and right sides of the vehicle body form the target detection area Y. Each obstacle detector 68 has a roughly conical target detection area Y. Each obstacle detector 68 transmits the detection information obtained during its detection to the corresponding detection information processing device 69.

Each detection information processing device 69 determines whether an obstacle has approached within close range of the vehicle body based on the time between transmission and reception of ultrasonic waves by the corresponding obstacle detector 68, and outputs the determination result to the travel suppression control unit 30D.

As a result, if an obstacle approaches abnormally close to the vehicle in front or to the left or right sides during autonomous driving, the obstacle's approach will be detected by the obstacle detection module 64.

Incidentally, for example, when the vehicle is driving autonomously towards a ridge, or when the vehicle is driving autonomously along the edge of a ridge, and the ridge comes abnormally close to the vehicle, the obstacle detection module 64 will detect the ridge as an obstacle. Also, when a moving object comes abnormally close to the vehicle, the obstacle detection module 64 will detect the moving object as an obstacle.

[About obstacle detectors]
Each obstacle detector 65 employs a laser scanner having a planar detection target area X and a maximum detection angle of approximately 270 degrees. Each obstacle detector 65 is equipped with a detection unit that detects obstacles and a processing unit that processes detection information from the detection unit. The detection unit irradiates the detection target area X with a laser beam and receives the reflected light. The processing unit determines whether an obstacle is approaching at a short distance from the vehicle body based on the time between the irradiation of the laser beam and the reception of the light, and outputs the determination result to the traveling suppression control unit 30D.

The area in front of the vehicle body is set as the detection target area X for the front obstacle detectors 65. The area in front and to the sides of the main body of the vehicle body is set as the first detection target area X1, and a pair of left and right obstacle detectors 65 are provided to detect obstacles present in the first detection target area X1. In addition, the area behind the vehicle body's work implement W is set as the second detection target area X2, and a rear obstacle detector 102 is provided to detect obstacles present in the second detection target area X2.

As shown in Figure 5, the first detection target area X1 and the second detection target area X2 are set within a range that does not detect the ground of the field, even if the vehicle body rolls or pitches slightly in response to the undulations of the field during work travel, for example.

As shown in Figures 1 to 3, 4, etc., each obstacle detector 65 is attached to a support frame extending in the vertical direction. Here, the support frame is a front pillar 73 provided on the cabin 4.

In other words, as shown in FIG. 2, each obstacle detector 65 is located between the outer edge of the hood 16 and the outermost position M of the main body of the vehicle in the left-right direction. Furthermore, each obstacle detector 65 is located between the upper end of the hood 16 and the upper ends of the front wheels 9 in the up-down direction. Furthermore, each obstacle detector 65 is located in the middle of the front-to-rear of the main body of the vehicle. Here, the middle of the front-to-rear of the main body of the vehicle refers to an area that extends to a certain extent in both the front and rear directions, with the middle of the front-to-rear of the main body of the vehicle as its center.

Furthermore, each obstacle detector 65 is positioned between the front axle 9A of the front wheels 9 and the rear axle 10A of the rear wheels 10 in the longitudinal direction. This makes it possible to set the first detection target area X1 so that obstacles can be detected effectively even when the vehicle body is tilted on complex terrain.

As shown in Figures 5 to 7, the first detection target area X1 of each obstacle detector 65 is set to be inclined forward, backward, left, and right with respect to the horizontal plane. To explain further, as shown in Figure 5, the detection target area X of each obstacle detector 65 is inclined downward at the front and upward at the rear. Furthermore, the first detection target area X1 of each obstacle detector 65 is set to pass through the upper front side of the front wheel 9. Furthermore, the first detection target area X1 of each obstacle detector 65 is set to pass through the upper front side of the weight 1A. Furthermore, as shown in Figure 7, the first detection target area X1 of each obstacle detector 65 is inclined downward from the lateral inner side of the aircraft toward the lateral outer side of the aircraft.

As shown in Figures 5 and 6, the rear obstacle detector 102 has a second detection target area X2 set to the area behind the work implement W on the rear side of the vehicle body. The second detection target area X2 of the rear obstacle detector 102 is set to have a rearward-sloping inclination angle. The second detection target area X2 is set to be wider in the left-right direction than the width of the work implement W.

The traveling suppression control unit 30D shown in FIG. 4 has a control program and the like that enables the execution of traveling suppression control. When the traveling suppression control unit 30D confirms that an obstacle is approaching the vehicle body at close range based on the discrimination results of each obstacle detector 65 and the rear obstacle detector 102, it initiates traveling suppression control, prioritizing automatic driving based on the control operation of the automatic driving control unit 30C. The traveling suppression control unit 30D then performs traveling suppression control based on the discrimination results of each obstacle detector 65, rear obstacle detector 102, and each detection information processing device 69.

During travel suppression control, the travel suppression control unit 30D outputs a deceleration command to the travel suppression control unit 30A upon initiation of travel suppression control. This causes the travel suppression control unit 30D to decelerate the main transmission 32 through control operation of the travel suppression control unit 30A, thereby reducing the vehicle speed from the set speed for normal travel to the set speed for contact avoidance. During this low-speed travel state, when the travel suppression control unit 30D confirms, based on the determination results of one of the exploration information processing devices 69, that an obstacle is approaching within close range of the vehicle body, it outputs an emergency stop command to the travel suppression control unit 30A and the work control unit 30B. This causes the travel suppression control unit 30D to switch the forward/reverse switching device 33 to a neutral state through control operation of the travel suppression control unit 30A, and to operate the left and right brakes through operation of the brake operation unit 35 to brake the left and right front wheels 9 and the left and right rear wheels 10. Furthermore, the travel suppression control unit 30D switches the PTO clutch 34 to a disengaged state through operation of the work control unit 30B, thereby stopping the operation of the work device W. As a result, the vehicle body can be quickly stopped from traveling and the working implement W can be quickly deactivated based on the approach of an obstacle within close range of the vehicle body, preventing the vehicle body from coming into contact with the obstacle. When the traveling suppression control unit 30D determines, based on the results of the obstacle detectors 65, that there are no obstacles within close range of the vehicle body during this low-speed traveling state, it outputs a speed increase command to the traveling control unit 30A and then terminates the traveling suppression control. As a result, the traveling suppression control unit 30D increases the speed of the main transmission 32 through the control operation of the traveling control unit 30A, increasing the vehicle speed from the set speed for contact avoidance to the set speed for normal traveling, and then resumes automatic driving based on the control operation of the automatic driving control unit 30C.

Each of the surveillance cameras 66 shown in Figures 1 to 4 employs a wide-angle visible light CCD camera. One of the four surveillance cameras 66 is used to photograph the front of the vehicle body. This surveillance camera 66 is installed in a tilted position so that its shooting direction faces downward and forward, in the center of the left and right at the front end of the upper end of the cabin 4. One of the four surveillance cameras 66 is used to photograph the right of the vehicle body. This surveillance camera 66 is installed in a tilted position so that its shooting direction faces downward and right, at the right end of the upper end of the cabin 4, with a predetermined distance between them in the front and rear. One of the four surveillance cameras 66 is used to photograph the left of the vehicle body. This surveillance camera 66 is installed in a tilted position so that its shooting direction faces downward and left, at the left end of the upper end of the cabin 4, with a predetermined distance between them in the front and rear. One of the four surveillance cameras 66 is used to photograph the rear of the vehicle body. This surveillance camera 66 is installed in a tilted position so that its shooting direction faces downward and rear, in the center of the left and right at the rear end of the upper end of the cabin 4. This allows you to capture the entire area around the vehicle without leaving anything out.

The image processing device 67 shown in Figure 4 processes the video signals from each surveillance camera 66 to generate an image of the front of the vehicle, an image of the right side of the vehicle, an image of the left side of the vehicle, an image of the rear of the vehicle, and an overhead image as if looking down from directly above the vehicle, and transmits these to the display unit 23, etc. The display unit 23 has a control unit 23B, etc. that switches the image displayed on the liquid crystal panel 23A based on manual operation of various operation switches (not shown) displayed on the liquid crystal panel 23A, etc.

With the above configuration, during manual driving, the driver can easily see the surrounding conditions and work status of the vehicle while driving by displaying images from the image processing device 67 on the LCD panel 23A. This allows the driver to easily drive the vehicle appropriately according to the type of work, etc. Furthermore, when a manager is in the vehicle during autonomous driving, the manager can easily see the surrounding conditions and work status of the vehicle while autonomously driving by displaying images from the image processing device 67 on the LCD panel 23A. Furthermore, if the manager sees an abnormality around the vehicle or the work status during autonomous driving, he or she can quickly take appropriate action according to the type and degree of the abnormality, etc.

As shown in FIG. 4, the electronic control system 51 is equipped with a cooperative control unit 70 that causes the vehicle to automatically drive in coordination with other vehicles of the same specifications when cooperative driving mode is selected by manually operating the selector switch 50. The cooperative control unit 70 is equipped with a communication module 71 that wirelessly communicates information regarding cooperative driving with other vehicles, including vehicle position information, with the other vehicles, and a cooperative driving control unit 30E that performs cooperative driving control based on information from the other vehicles. The cooperative driving control unit 30E is equipped in the main ECU 30 and has a control program that enables the execution of cooperative driving control.

In cooperative driving mode, the automatic driving control unit 30C transmits various control commands to the driving control unit 30A and the work control unit 30B at appropriate times based on the target driving route for parallel driving and the positioning results of the positioning unit 53, etc., so that the vehicle body automatically drives along a predetermined target driving route for parallel driving at a set speed while performing work appropriately. The cooperative driving control unit 30E determines whether the inter-vehicle distance between the preceding vehicle and the subject vehicle in the direction of travel and the inter-vehicle distance between the preceding vehicle and the subject vehicle in the direction of parallel driving are appropriate based on the target driving route for parallel driving of the subject vehicle, the positioning results of the positioning unit 53, the target driving route for parallel driving of the other vehicle, and the position information of the other vehicle. If any inter-vehicle distance is not appropriate, cooperative driving control is initiated in preference to automatic driving based on the control operation of the automatic driving control unit 30C so that the inter-vehicle distance is appropriate.

During cooperative driving control, if the inter-vehicle distance in the direction of travel is shorter than the appropriate distance, the cooperative driving control unit 30E outputs a deceleration command to the cruise control unit 30A. This causes the cooperative driving control unit 30E to decelerate the main transmission 32 through the control operation of the cruise control unit 30A, restoring the inter-vehicle distance in the direction of travel to the appropriate distance. Then, as the inter-vehicle distance in the direction of travel returns to the appropriate distance, the cooperative driving control unit 30E resumes automatic driving based on the control operation of the automatic driving control unit 30C, thereby increasing the vehicle speed to the set speed for normal driving and maintaining the inter-vehicle distance in the direction of travel at the appropriate distance.

If the inter-vehicle distance in the direction of travel is longer than the appropriate distance, the cooperative driving control unit 30E outputs a speed increase command to the cruise control unit 30A. This causes the cooperative driving control unit 30E to increase the speed of the main transmission 32 through the control operation of the cruise control unit 30A, thereby restoring the inter-vehicle distance in the direction of travel to the appropriate distance. Then, as the inter-vehicle distance in the direction of travel returns to the appropriate distance, the cooperative driving control unit 30E resumes automatic driving based on the control operation of the automatic driving control unit 30C, thereby reducing the vehicle speed to the set speed for normal travel and maintaining the inter-vehicle distance in the direction of travel at the appropriate distance.

If the inter-vehicle distance in the parallel driving direction is longer than the appropriate distance, the cooperative driving control unit 30E outputs a steering command to the cruise control unit 30A toward the other vehicle. This causes the cooperative driving control unit 30E to steer the left and right front wheels 9 toward the other vehicle through the control operation of the cruise control unit 30A, thereby restoring the inter-vehicle distance in the parallel driving direction to the appropriate distance. Then, as the inter-vehicle distance in the parallel driving direction returns to the appropriate distance, the cooperative driving control unit 30E resumes automatic driving based on the control operation of the automatic driving control unit 30C, thereby returning the vehicle's direction of travel to the normal driving direction and maintaining the inter-vehicle distance in the parallel driving direction at the appropriate distance.

If the inter-vehicle distance in the parallel driving direction is shorter than the appropriate distance, the cooperative driving control unit 30E outputs a steering command to the cruise control unit 30A to steer away from the other vehicle. This causes the cooperative driving control unit 30E to steer the left and right front wheels 9 away from the other vehicle through the control operation of the cruise control unit 30A, thereby restoring the inter-vehicle distance in the parallel driving direction to the appropriate distance. Then, as the inter-vehicle distance in the parallel driving direction returns to the appropriate distance, the cooperative driving control unit 30E resumes automatic driving based on the control operation of the automatic driving control unit 30C, thereby returning the vehicle's direction of travel to the normal driving direction and maintaining the inter-vehicle distance in the parallel driving direction at the appropriate distance.

This allows the vehicle to automatically and appropriately travel alongside the vehicle ahead while maintaining the correct distance between the vehicles in both directions.

As shown in Figures 1 to 4, the cabin 4 is equipped with a roof frame 72 that supports the roof 62, etc., left and right front pillars 73 that support the front end of the roof frame 72, left and right center pillars 74 that support the middle portion of the roof frame 72 between the front and rear, left and right rear pillars 75 that support the rear side of the roof frame 72, a front panel 76 that forms the front of the cabin 4, left and right door panels 77 that are supported on the left and right center pillars 74 so that they can swing open and close, left and right side panels 78 that form the rear side surfaces of the cabin 4, and a rear panel 79 that is supported on the roof frame 72 so that it can swing open and close.

The left and right front pillars 73 are positioned further forward than the center of the wheelbase L of the main body of the vehicle body. The left and right front pillars 73 are curved in their upper halves so that the upper halves are positioned closer to the left-right center of the vehicle body in a front view, and the upper halves are positioned closer to the front-to-rear center of the vehicle body in a side view. Direction indicators 100 (blinkers) are supported on each of the left and right front pillars 73. Furthermore, a rearview mirror 101, which can be rotated freely around a vertical axis and whose mirror surface can be adjusted forward, backward, left, and right, is supported above the direction indicators 100 on each of the left and right front pillars 73.

As shown in Figures 1 to 4, the cabin 4 is equipped with auxiliary frames 90 that extend rearward from the upper ends of the left and right rear pillars 75. The auxiliary frames 90 support a rear obstacle detector 102, a surveillance camera 66 for capturing rearward images, and other components.

[About the obstacle detector]
1, 3, and 4, each obstacle detector 68 is mounted on the vehicle body at a position at least above the left and right front wheels 9. As a result, even if one of the obstacle detectors 68 approaches the ground of the field due to the vehicle body rolling or pitching in response to the undulations of the field during work travel, the distance from the ground of each obstacle detector 68 at this time can be maintained longer than the detection distance of each obstacle detector 68.

In other words, each obstacle detector 68 is positioned at an appropriate height to prevent the ground of the field from coming within the detection distance of each obstacle detector 68, even if the vehicle body rolls or pitches in response to the undulations of the field during work travel. This prevents each obstacle detector 68 from erroneously detecting the ground of the field as an obstacle due to the rolling or pitching of the vehicle body during work travel.

The area Y to be explored by the obstacle detector 68 includes a first area Y1 to be explored, a second area Y2 to be explored, a third area Y3 to be explored, and a fourth area Y4 to be explored.

The obstacle detectors 68 include a pair of first obstacle detectors 68A (left and right) with a first detection target area Y1 on the sides of the rear end of the main body of the vehicle body, a pair of second obstacle detectors 68B (left and right) with a second detection target area Y2 on the sides of the central fore-aft part of the vehicle body (corresponding to the "side obstacle detectors" in this invention) , a pair of third obstacle detectors 68C (left and right) with a third detection target area Y3 on the sides of a location in the central fore-aft part of the vehicle body that is forward of the second obstacle detectors 68B, and a pair of fourth obstacle detectors 68D (left and right) with a fourth detection target area Y4 on the front side of the vehicle body (corresponding to the "front obstacle detectors" in this invention) .

As shown in Figures 1 to 3, the two first obstacle detectors 68A are attached to the rear of the rear fenders 12. Specifically, each first obstacle detector 68A is attached to a location on the left and right rear fenders 12 rearward of the rear axles 10A of the left and right rear wheels 10. Each first obstacle detector 68A is capable of detecting obstacles present in a first detection target area Y1. The first detection target area Y1 is set to extend downward laterally from the first obstacle detector 68A.

Two second obstacle detectors 68B are attached to the front of the rear fender 12. Each second obstacle detector 68B is capable of detecting obstacles present in a second target detection area Y2. The second target detection area Y2 is set to extend downward and to the lateral side from the second obstacle detector 68B.

The two third obstacle detectors 68C are attached to the left and right front pillars 73 located in the middle of the vehicle body in the cabin 4. Each third obstacle detector 68C is capable of detecting obstacles present in a third target detection area Y3. The third target detection area Y3 is set to extend downward to the outside of the third obstacle detector 68C.

As shown in Figures 1 to 4, of the eight obstacle detectors 68 mentioned above, a pair of left and right fourth obstacle detectors 68D are attached at the top-bottom center of the front end of the hood 16, spaced a predetermined distance apart in the left-right direction. Each fourth obstacle detector 68D is capable of detecting obstacles present in a fourth search target area Y4. The left and right fourth obstacle detectors 68D enable the search target area Y in front of the vehicle body to be widened in the left-right direction. The fourth search target area Y4 is set to extend downward and to the outside of the fourth obstacle detector 68D.

As shown in Figure 1, the third obstacle detector 68C and the obstacle detector 65 are located below the rearview mirror 101.

The first detection target area Y1 by the first obstacle detector 68A and the second detection target area X2 by the rear obstacle detector 102 shown in Figures 5 and 6 are each optimally adjusted according to the type and left-right width of the work implement W.

Furthermore, the detection target area X has limits set on its outer edges to prevent detecting the ground rather than an obstacle. Note that in Figure 6, the left and right edges of the first detection target area X1 are shown as straight lines, but this is shown only diagrammatically for convenience of illustration.

With the above installation, the left and right sides of the rear of the vehicle body where the left and right rear fenders 12 are located become the first search target area Y1 of the left and right first obstacle detectors 68A, the front of the rear wheels 10 on the vehicle body where the left and right rear fenders 12 are located become the second search target area Y2 of the left and right second obstacle detectors 68B, and the left and right sides of the center of the vehicle body where the left and right front pillars 73 are located become the third search target area Y3 of the left and right third obstacle detectors 68C. In other words, the left and right first obstacle detectors 68A, the left and right second obstacle detectors 68B, and the left and right third obstacle detectors 68C can make the search target area Y a wide area on the sides of the vehicle body in the fore-and-aft direction. As a result, obstacles located close to the sides of the vehicle body can be detected without omission.

As a result, based on the detection by each obstacle detector 68, it is possible to prevent the vehicle from transitioning to a running state when a moving obstacle (such as an animal or an object rolling in the wind) is approaching the stationary vehicle, and it is also possible to more reliably prevent the vehicle from coming into contact with an obstacle during autonomous driving.

As shown in FIG. 2, the left and right first obstacle detectors 68A are attached to the left and right rear fenders 12 via left and right support members. In other words, the left and right first obstacle detectors 68A are positioned above the lateral outer ends of the left and right rear wheels 10, respectively. This allows the left and right first obstacle detectors 68A to smoothly detect obstacles without being obstructed by the left and right rear wheels 10.

As shown in Figures 1 to 3, the left and right third obstacle detectors 68C are attached to the left and right front pillars 73. In other words, the left and right third obstacle detectors 68C are disposed between the left and right front wheels 9 and the left and right rear wheels 10, respectively. This allows the areas between the left and right front wheels 9 and the left and right rear wheels 10 to be included in the detection target area Y of the left and right third obstacle detectors 68C, and the presence or absence of an obstacle between the left and right front wheels 9 and the left and right rear wheels 10 can be detected by the left and right third obstacle detectors 68C.

As shown in Figures 1 to 4, the mounting orientation of the first left obstacle detector 68A is set to a left-downward orientation, with the transmitting and receiving surface facing downward and left. The mounting orientation of the first right obstacle detector 68A is set to a right-downward orientation, with the transmitting and receiving surface facing downward and right. The mounting orientation of the second left obstacle detector 68B is set to a left-facing orientation, with the transmitting and receiving surface facing sideways to the left. The mounting orientation of the second right obstacle detector 68B is set to a right-facing orientation, with the transmitting and receiving surface facing sideways to the right. The mounting orientation of the third left obstacle detector 68C is set to a left-downward orientation, with the transmitting and receiving surface facing downward and left. The mounting orientation of the third right obstacle detector 68C is set to a right-downward orientation, with the transmitting and receiving surface facing downward and right. The mounting orientations of the fourth left and right obstacle detectors 68D are each set to a forward-facing orientation, with the transmitting and receiving surface facing forward.

In Figure 6, the area indicated by the bold dashed line indicates the area in which the obstacle detector 65 can detect obstacles that are located below a predetermined height. Furthermore, in Figure 6, the area indicated by the thin dashed line indicates the area in which the obstacle detector 65 cannot detect obstacles that are located below a predetermined height.

As shown in Figures 5 and 6, the first exploration target area Y1 of the first obstacle detector 68A, the second exploration target area Y2 of the second obstacle detector 68B, and the third exploration target area Y3 of the third obstacle detector 68C cover areas on the sides of the vehicle body that are not included in the detection target area X of the obstacle detector 65 (areas that are blind spots for the obstacle detector 65), making it possible to detect obstacles.

In this way, by covering the area not included in the detection target area X of each obstacle detector 65 with the detection target area Y of each obstacle detector 68, it is possible to reduce blind spots around the vehicle where no obstacles are detected. This makes it possible to accurately detect obstacles around the vehicle while it is moving, and to stop the vehicle from coming into contact with an obstacle.
Furthermore, if a moving obstacle (for example, an animal, something moved by the wind, etc.) moves near the vehicle body while the vehicle is stopped, the obstacle can be detected with high accuracy and the vehicle is prevented from transitioning from the stopped state to the running state, thereby avoiding inconveniences such as the running device 2 or the working device W stepping over the obstacle.

[Another embodiment]
The following describes other embodiments that are modifications of the above embodiment. Multiple combinations of the above embodiments can be applied to the above embodiment, provided no contradictions arise. The scope of the present invention is not limited to the contents of each embodiment.

(1) The obstacle detectors 65 do not have to be provided in pairs, one on each side. Specifically, the first detection target area X1 of the left obstacle detector 65 and the first detection target area X1 of the right obstacle detector 65 may be asymmetric. Furthermore, an obstacle detector 65 may be provided on only one side, either the left or right.

(2) The obstacle detector 65 does not have to be attached to the front pillar 73. For example, the obstacle detector 65 may be attached to the rearview mirror 101. Also, for example, the obstacle detector 65 may be attached to a frame near the turn signal 100. By locating the obstacle detector 65 near the turn signal 100, the harness for the obstacle detector 65 and the harness for the turn signal 100 can be wired together.

(3) Instead of the cabin 4, a gate-shaped ROPS frame may be provided, located behind the driver's seat 22, and having a pair of left and right support pillars and a beam connecting the upper ends of the left and right support pillars.
In this case, the obstacle detector 65 may be attached to the ROPs frame. Specifically, the obstacle detector 65 may be attached to the support portion of the ROPs frame or to the beam portion of the ROPs frame.

(4) The driver's section 17 may be provided with an extension frame extending from the tip of the platform where the passenger's feet are positioned to the hood 16. In this case, the obstacle detector 65 can be attached to the extension frame.

(5) The first obstacle detector 68A and the second obstacle detector 68B may be attached to a member other than the rear fender 12.

(6) The obstacle detector 65 may be a device other than a laser scanner.

(7) The obstacle detector 65 may be positioned in a location that is not between the outer edge of the hood 16 and the outermost position M of the main body of the vehicle in the left-right direction.

(8) The obstacle detector 65 may be located in a location other than the mid-front/rear portion of the vehicle body.

(9) The first detection target area X1 of the obstacle detector 65 may be set so as to be inclined only forward and backward relative to the horizontal plane, or may be set so as to be inclined only left and right relative to the horizontal plane.

(10) The obstacle detector 68 may be a device other than an ultrasonic sensor. For example, an infrared distance measuring sensor or the like may be used as the obstacle detector 68.

(11) The left and right first obstacle detectors 68A may be positioned above the headlights 107 at the front end of the hood 16.

(12) The number of obstacle detectors 68 may be 10 or more, and if the overall length of the work vehicle is short, the number of obstacle detectors 68 may be 6 or less.

(13) The vehicle may be configured as a semi-crawler vehicle, with left and right crawlers instead of the left and right rear wheels 10.

(14) The vehicle may be configured as a full crawler vehicle, with left and right crawlers instead of the left and right front wheels 9 and the left and right rear wheels 10.

(15) It may also be a two-wheel drive type in which either the left or right front wheels 9 or the left or right rear wheels 10 are driven.

(16) The vehicle may be configured for electric operation with an electric motor instead of the engine 6.

(17) It may also be configured as a hybrid vehicle equipped with an engine 6 and an electric motor.

The present invention can be used in work vehicles equipped with an electronic control system for automatic driving, which allows the vehicle body to be driven automatically. For example, in addition to the tractors mentioned above, it can also be used in riding brush cutters, combine harvesters, riding rice transplanters, wheel loaders, etc.

12: Rear fender 30D: Travel suppression control unit 51: Electronic control system 64: Obstacle detection module 65: Obstacle detector 68: Obstacle probe 68A: First obstacle probe 68B: Second obstacle probe X: Detection target area Y: Search target area

Claims (4)

The car body and
a lifting device capable of attaching a working device to the vehicle body;
a cabin provided in the vehicle body;
a hood provided at the front side of the cabin;
an obstacle detector and an obstacle probe;
A tractor comprising:
A tractor in which the obstacle detector is provided at the rear of the cabin to detect the area behind the lifting device, side obstacle detectors which are obstacle detectors are provided to the outside of the cabin door in the left-right direction of the vehicle body , and multiple front obstacle detectors which are obstacle detectors are provided at the front of the hood. The tractor described in claim 1, wherein the obstacle detector provided in the cabin is provided on the underside of the roof of the cabin. 3. The tractor according to claim 1, wherein the side obstacle detector is provided on a rear fender on the side of the cabin. The tractor according to any one of claims 1 to 3, further comprising a second obstacle detector having a detection target area that at least partially overlaps with the detection target areas of the plurality of front obstacle detectors.