tractor

Abstract

To enable the vehicle to properly avoid contact with obstacles. [Solution] A tractor comprising a vehicle body, a lifting device on which a work device W can be attached to the vehicle body, a cabin provided on the vehicle body, a bonnet 4 provided on the front side of the cabin, an obstacle detector 102 and obstacle detectors 68, wherein the obstacle detector 102 is provided on the rear side of the cabin 4 and behind the lifting device, a first obstacle detector 68 is provided on the side of the door of the cabin 4, and a plurality of second obstacle detectors 68 are provided on the front side of the bonnet.

Description

Technical Field

[0001] The present invention relates to a tractor.

Background Art

[0002] An example of the above work vehicle (tractor) is described in, for example, Patent Document 1 below. The work vehicle described in this document is provided with obstacle detection means capable of detecting obstacles existing in front of the vehicle body at the front part of the vehicle body. In this work vehicle, when an obstacle is detected by the obstacle detection means, the automatic operation (autonomous running) of the vehicle body is stopped to avoid the vehicle body coming into contact with an obstacle existing in front of the vehicle body.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] However, in the above conventional technology, the obstacle detection means can only detect obstacles existing in front of the vehicle body, and obstacles existing on the rear side of the vehicle body are not detected. Therefore, there is a possibility that an obstacle may come into contact with a working device or the like located on the rear side of the vehicle body.

[0005] In view of the above situation, it is desired to be able to appropriately avoid the vehicle body from coming into contact with an obstacle.

Means for Solving the Problems

[0006] The tractor of the present invention is The vehicle comprises a vehicle body, left and right front wheels and rear wheels mounted on the vehicle body, and an obstacle detector mounted on the vehicle body for detecting obstacles. The obstacle detector is positioned between the front axle of the front wheels and the rear axle of the rear wheels in the front-rear direction, and the area in front of and to the side of the vehicle body is set as the detection target area. . In the present invention, it is preferable that a weight is provided at the front end of the vehicle body, and that the detection target area is set to pass in front of and above the weight. In the present invention, an obstacle detector is provided on the side of the vehicle body for detecting obstacles, and the obstacle detector has a search target area set on the side of the vehicle body, and it is preferable that the rear end of the search target area is located behind the front end of the search target area. In the present invention, it is preferable that a cabin is provided on the rear side of the vehicle body, and the obstacle detector is provided on the front side of the cabin. In the present invention, it is preferable that the obstacle detector is positioned on the side of the vehicle body, behind the front wheels. In the present invention, it is preferable that the detection target area is set to pass over the front upper side of the front wheel. In the present invention, the obstacle detector is preferably located in the center of the front and rear of the vehicle body. In the present invention, it is preferable that a bonnet is provided to cover the upper part of the drive unit located at the front of the vehicle body, and that the obstacle detector is positioned between the upper end of the front wheel and the upper end of the bonnet.

[0007] According to the present invention, a pair of left and right first obstacle detectors can detect obstacles located near the rear end of the vehicle body. When an obstacle is detected by the pair of left and right first obstacle detectors, the vehicle's movement is suppressed. Therefore, for example, if an obstacle exists between the work device located at the rear end of the vehicle and the vehicle body, it is possible to avoid the vehicle transitioning from a stopped state to a moving state. This avoids problems such as the work device running over an obstacle, and improves the reliability of autonomous driving.

[0008] Thus, with this invention, it becomes possible to avoid obstacles coming into contact with the rear of the vehicle body.

[0009] In the present invention, Preferably, the first obstacle detector is mounted on the rear of the rear fender.

[0010] With the above configuration, obstacles located near the rear end of the rear wheel, below the rear fender, can be accurately detected by the first obstacle detector.

[0011] In the present invention, Preferably, the obstacle detector is provided with a pair of left and right second obstacle detectors whose detection area is the side of the front and rear central part of the vehicle body.

[0012] With the above configuration, obstacles located to the sides of the front-to-rear central section of the vehicle body can be accurately detected by the second obstacle detector.

[0013] In the present invention, Preferably, the second obstacle detector is mounted on the front of the rear fender.

[0014] According to the above configuration, an obstacle existing near the front end of the rear wheel located below the rear fender can be accurately detected by the second obstacle detector.

[0015] In the present invention, the obstacle detection module is provided with an obstacle detector that detects an obstacle existing in the detection target area by a detection method different from that of the obstacle detector. It is preferable that the detection target area of the obstacle detector includes an area located below the detection target area of the obstacle detector.

[0016] According to the above configuration, by covering an area below the detection target area of the obstacle detector with the detection target area of the obstacle detector, the area that becomes a blind spot where an obstacle cannot be detected is reduced, and an obstacle existing around the vehicle body that may interfere with automatic driving can be detected without omission.

[0017] In the present invention, it is preferable that the obstacle detector is an ultrasonic sonar.

[0018] According to the above configuration, by using a relatively inexpensive ultrasonic sonar for detecting an obstacle, an increase in the overall cost can be suppressed.

Brief Description of the Drawings

[0019] [Figure 1] It is a left side view of a tractor showing the arrangement of an obstacle detector and an obstacle detector, etc. [Figure 2] It is a top view of a tractor showing the arrangement of an obstacle detector and an obstacle detector, etc. [Figure 3] It is a perspective view of a tractor showing the arrangement of an obstacle detector and an obstacle detector, etc. [Figure 4] It is a block diagram showing a schematic configuration of a control system. [Figure 5] It is a schematic left side view showing the detection target area by the obstacle detector and the detection target area by the obstacle detector. [Figure 6]This is a schematic top view diagram showing the area to be explored by the obstacle detector and the area to be detected by the obstacle sensor. [Figure 7] This is a schematic diagram showing the front view of the area detected by the obstacle detector. [Modes for carrying out the invention]

[0020] Hereinafter, an embodiment of the present invention will be described based on the drawings. Note that the arrow labeled F in Figures 1 and 2 points forward, the arrow labeled U in Figure 1 points upward, and the arrow labeled R in Figures 1 and 2 points to the right.

[0021] As shown in Figures 1 to 3, the tractor (an example of a "work vehicle") is equipped with a body frame 1 that extends from both the front and rear ends of the vehicle body, left and right running gears 2 positioned on the left and right sides of the body frame 1, a drive unit 3 positioned on the front side of the body frame 1, a cabin 4 positioned 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) that is mounted on the rear end of the body frame 1 so as to be able to move up and down and swing. As shown in Figures 1 and 2, a weight 1A is attached to the front end of the body frame 1.

[0022] As shown in Figures 1 to 3, the vehicle frame 1 includes a front frame 7 extending from the lower part of the engine 6 located in the drive unit 3 towards the front of the vehicle, and a case unit 8 that also serves as a rear frame extending from the lower rear end of the engine 6 towards the rear of the vehicle. Although not shown in the figures, the case unit 8 contains a pedal-operated main clutch that intermittently switches power from the engine 6, a transmission unit that branches the power from the main clutch into driving and working power and changes the speed, and left and right side brakes that act on the left and right running gears 2.

[0023] As shown in Figures 1 to 3, the left and right running gears 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 drivable and steerable at both ends of a wheel support member 11 that is supported by the front frame 7 in a rolling manner. The wheel support member 11 is a front axle case that houses the transmission shaft for front wheel drive inside. The left and right rear wheels 10 are drivable and supported by a case unit 8, and the upper side of each rear wheel 10 is covered by left and right rear fenders 12 located at the rear of the vehicle body.

[0024] As shown in Figures 1 to 3, the power unit 3 is equipped with a water-cooled engine 6 located on the rear side of the vehicle body of the power unit 3, which is on the cooling side of the power unit 3; a cooling fan 13 located on the front side of the vehicle body, which is on the cooling side of the engine 6; a radiator 14 located in front of the cooling fan 13; a battery (not shown) located in front 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 / close bonnet 16 that covers the engine 6, radiator 14, etc. 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) and a DPF (Diesel Particulate Filter), etc.

[0025] As shown in Figures 1 to 3, the cabin 4 forms a driver's compartment 17 and a passenger compartment at the rear of the vehicle body. The driver's compartment 17 is equipped with a clutch pedal 18 for operating the main clutch, left and right brake pedals (not shown) for operating the left and right handbrakes, a steering wheel 19 for 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 with a touch-operable liquid crystal panel, etc. The steering wheel 19 is linked to the left and right front wheels 9 via a steering mechanism 25 having a fully hydraulic power steering unit (hereinafter referred to as PS unit 24). The armrest 21 is equipped with a main gear lever 26 (see Figure 4), a lifting lever 27 (see Figure 4) for setting the height position of the work device W, and a lifting switch 28 (see Figure 4) for commanding the lifting and lowering of the work device W.

[0026] As shown in Figures 1 to 3, the three-point linkage mechanism 5 is driven to swing vertically by the operation of an electronically hydraulic lifting drive unit 29 mounted on the vehicle body, as shown in Figure 4. As shown in Figures 5 and 6, various working devices W such as rotary tillers, plows, disc harrows, cultivators, subsoilers, seeders, and sprayers can be connected to the three-point linkage mechanism 5. When the working device W connected to the three-point linkage mechanism 5 is a rotary tiller or the like that is driven by power from the vehicle body, the working power taken from the transmission unit is transmitted to the working device W via an external transmission shaft.

[0027] As shown in Figure 4, the vehicle body is equipped with a main electronic control unit (hereinafter referred to as the main ECU 30) and an electronic control unit for the engine (hereinafter referred to as the engine ECU 31). The main ECU 30 is connected to the aforementioned electronically controlled lifting drive unit 29, the electronic control unit for the engine (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 transmission unit, the electronically controlled 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, etc., via an in-vehicle LAN such as CAN (Controller Area Network) or communication lines. The main ECU 30 and the engine ECU 31 are equipped with microprocessors having a CPU and EEPROM, etc. The main ECU 30 is equipped with a driving control unit 30A that controls the movement of the vehicle body, and a work control unit 30B that controls the work device W, etc.

[0028] The main transmission 32 employs a hydrostatic continuously variable transmission that continuously changes the speed of the power used for driving. The forward / reverse switching device 33 also functions as a drive clutch that intermittently switches the power used for driving. Although not shown in the diagram, the transmission unit is equipped with the main transmission 32 and the like, as well as a sub-transmission that changes the power used for driving in steps, and a PTO transmission that changes the power used for work in steps.

[0029] As shown in Figure 4, the in-vehicle information acquisition unit 36 ​​includes various sensors and switches, such as a rotation sensor 37 for detecting the output rotation speed of the engine 6, a vehicle speed sensor 38 for detecting the output rotation speed of the sub-transmission as vehicle speed, a first lever sensor 39 for detecting the operating position of the main transmission lever 26, a second lever sensor 41 for detecting the operating position of the sub-transmission lever 40 provided in the driver's unit 17, a third lever sensor 42 for detecting the operating position of the shuttle lever 20, a fourth lever sensor 43 for detecting the operating position of the lifting lever 27, the aforementioned lifting switch 28, a swivel lift switch 44, a reverse lift switch 45, and a PTO switch 46 provided in the driver's unit 17, a height sensor 47 for detecting the vertical swing angle of the left and right lift arms (not shown) in the lifting drive unit 29 as the height position of the work device W, and a steering angle sensor 48 for detecting the steering angle of the front wheels 9.

[0030] The driving control unit 30A has various control programs that enable control over the vehicle's movement. Based on the output of the rotation sensor 37, the vehicle speed sensor 38, the first lever sensor 39, and the second lever sensor 41, the driving control unit 30A controls the vehicle speed by operating the trunnion shaft (not shown) of the main transmission 32 so that the vehicle speed reaches a target vehicle speed determined from the engine speed, the operating position of the main transmission lever 26, and the operating position of the sub-transmission lever 40. As a result, the driver can change the vehicle speed to any speed by operating the main transmission lever 26 to any position.

[0031] The driving control unit 30A performs forward / reverse switching control, which switches the forward / reverse switching device 33 to a transmission state corresponding to the operating position of the shuttle lever 20, based on the output of the third lever sensor 42. As a result, the driver can set the direction of travel of the vehicle to the forward direction by operating the shuttle lever 20 to the forward position. The driver can also set the direction of travel of the vehicle to the reverse direction by operating the shuttle lever 20 to the reverse position.

[0032] The work control unit 30B has various control programs 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 to control the operation of the lifting drive unit 29 so that the work device W is positioned at a height corresponding to the operating position of the lifting lever 27. As a result, the operator can change the height position of the work device W to any height position by operating the lifting lever 27 to any desired position.

[0033] When the lifting switch 28 is switched to the upward command state by manual operation of the lifting switch 28, the work control unit 30B performs upward control, controlling the operation of the lifting drive unit 29 so that the work device W rises to a preset upper limit position, based on the upward command from the lifting switch 28 and the output of the height sensor 47. As a result, the operator can automatically raise the work device W to the upper limit position by switching the lifting switch 28 to the upward command state.

[0034] When the lifting switch 28 is switched to the lowering command state by manual operation of the lifting switch 28, the work control unit 30B performs lowering control, controlling the operation of the lifting drive unit 29 so that the work device W descends to the work height position set by the lifting lever 27, based on the lowering command from the lifting switch 28, the output of the fourth lever sensor 43, and the output of the height sensor 47. As a result, the operator can automatically lower the work device W to the work height position by switching the lifting switch 28 to the lowering command state.

[0035] If the operation of the turning-linked lift control is selected by manual operation of the turning-lift switch 44, the work control unit 30B automatically performs the aforementioned lift control when it detects that the steering angle of the front wheels 9 has reached the set angle for turning along the edge of the ridge, based on the output of the steering angle sensor 48 which detects the steering angle of the front wheels 9. As a result, by selecting the operation of the turning-linked lift control, the operator can automatically raise the work device W to the upper limit position in conjunction with the start of turning along the edge of the ridge.

[0036] If the reverse-linked lift control is selected by manual operation of the reverse-lift switch 45, the work control unit 30B automatically performs the aforementioned lift control 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 the execution of the reverse-linked lift control, the driver can automatically raise the work device W to the upper limit position in conjunction with switching to reverse driving.

[0037] When the PTO switch 46 is manually operated and the operating position of the PTO switch 46 is switched to the "on" position, the work control unit 30B performs clutch engagement control, which switches the PTO clutch 34 to the "on" position based on the switch to the "on" position, so that power for the work is transmitted to the work device W. As a result, the operator can operate the work device W by operating the PTO switch 46 to the "on" position.

[0038] When the PTO switch 46 is manually operated and the PTO switch 46 is switched to the off position, the work control unit 30B performs clutch disengagement control, which switches the PTO clutch 34 to the off position to prevent power for work from being transmitted to the work device W. As a result, the operator can stop the work device W by operating the PTO switch 46 to the off position.

[0039] When the PTO switch 46 is manually operated and the operating position of the PTO switch 46 is switched to the automatic position, the work control unit 30B automatically performs the clutch disengagement control described above in conjunction with the execution of the lifting control described above, and also automatically performs the clutch engagement control described above in conjunction with the execution of the lowering control described above. As a result, by operating the PTO switch 46 to the automatic position, the operator can stop the work device W in conjunction with the automatic lifting of the work device W to the upper limit position, and operate the work device W in conjunction with the automatic lowering of the work device W to the working height position.

[0040] As shown in Figure 4, this tractor is equipped with a selection switch 50 that allows selection of driving modes such as manual driving mode and automatic driving mode, and an electronic control system 51 for automatic driving that automatically drives the vehicle when automatic driving mode is selected. The electronic control system 51 includes the aforementioned main ECU 30, 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 direction of the vehicle, and a monitoring unit 54 that monitors the area around the vehicle.

[0041] As shown in Figures 2 to 4, the automatic steering unit 52 is composed of the aforementioned PS unit 24. When manual driving mode is selected, the PS unit 24 steers the left and right front wheels 9 based on the rotational operation 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.

[0042] 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 system can be easily switched to manual steering by the occupant, allowing the vehicle to continue to be driven.

[0043] As shown in Figures 1 to 4, the positioning unit 53 is equipped with a satellite navigation device 60 that measures the position and direction of the vehicle using the well-known GPS (Global Positioning System), which is an example of a Global Navigation Satellite System (GNSS). There are various positioning methods using GPS, such as DGPS (Differential GPS) and RTK-GPS (Real Time Kinematic GPS), but in this embodiment, RTK-GPS, which is suitable for positioning moving objects, is used.

[0044] The satellite navigation system 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 positioning data obtained from receiving radio waves from GPS satellites to the satellite navigation system 60. The satellite navigation system 60 determines the position and bearing of the vehicle based on the positioning data obtained from receiving radio waves from GPS satellites and the positioning data from the reference station.

[0045] The antenna unit 61 is mounted on the roof 62 of the cabin 4, which is located at the top of the vehicle body, to enhance the sensitivity of receiving radio waves from GPS satellites. Therefore, the position and orientation of the vehicle body measured using GPS include positioning errors caused by displacement of the antenna unit 61 due to the yawing, pitching, or rolling of the vehicle body.

[0046] Therefore, the vehicle body is equipped with an inertial measurement unit (IMU) that has a 3-axis gyroscope (not shown) and 3-directional acceleration sensors (not shown) to measure the yaw angle, pitch angle, roll angle, etc. of the vehicle body, in order to enable correction to eliminate the above-mentioned positioning error. The inertial measurement unit 63 is installed inside the antenna unit 61 in order to make it easier to determine the amount of positional displacement of the antenna unit 61. The antenna unit 61 is mounted on the front upper surface of the cabin 4 roof 62 at the left-right center point so that, in a top view, it is located at the center of the wheelbase L and at the center of the tread T of the vehicle body (see Figure 2).

[0047] As shown in Figure 4, the main ECU 30 is equipped with an automatic driving control unit 30C that has various control programs that enable automatic driving of the vehicle. The automatic driving control unit 30C transmits various control commands to the driving control unit 30A and the work control unit 30B, etc., at appropriate timings based on the target driving route and the positioning results of the positioning unit 53, etc., so that the vehicle automatically drives along a pre-set 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 and the forward / reverse switching device 33, etc., at appropriate timings 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 and the forward / reverse switching device 33, etc. The work control unit 30B controls the operation of the lifting drive unit 29 and PTO clutch 34, etc., by transmitting various control commands to the lifting drive unit 29 and PTO clutch 34, etc., at appropriate timings, based on various control commands from the automatic driving control unit 30C and various acquired information from the in-vehicle information acquisition unit 36, etc.

[0048] As shown in Figures 1 to 4, the monitoring unit 54 is equipped with an obstacle detection module 64 for detecting the presence or absence of obstacles, a driving suppression control unit 30D that performs driving suppression control (contact avoidance control to avoid contact with obstacles) to suppress the movement of the vehicle when the obstacle detection module 64 detects an obstacle, four monitoring cameras 66 for taking pictures of the area around the vehicle, and an image processing device 67 for processing images taken by the monitoring cameras 66.

[0049] The obstacle detection module 64 shown in Figure 4 is equipped with multiple obstacle detectors 65 that detect obstacles in the target area Y, multiple obstacle detectors 68 that detect obstacles in the target area X, and two detection information processing devices 69 that perform a determination process to determine whether or not an obstacle has approached within close range to the vehicle based on the detection information from each obstacle detector 68. The obstacle detectors 65 detect the approach of obstacles at close range to the vehicle (e.g., within 10m). Each obstacle detector 68 detects the presence or absence of obstacles within close range to the vehicle (e.g., within 1m). In other words, the obstacle detection module 64 is equipped with obstacle detectors 65 that detect obstacles in the target area X using a different detection method than the obstacle detectors 68.

[0050] Figures 5 to 7 schematically show the detection area X of the obstacle detector 65 and the exploration area Y of the obstacle explorer 68. The exploration area Y of the obstacle explorer 68 includes an area located below the detection area X of the obstacle detector 65. Note that in Figures 5 to 7, the detection area X and the exploration area Y have been partially omitted for illustrative purposes.

[0051] The detection area X and the exploration area Y shown in Figures 5 to 7 are designed to change according to the vehicle speed. Specifically, both the detection area X and the exploration area Y increase as the vehicle speed increases.

[0052] Each obstacle detector 68 employs an ultrasonic sonar, which uses ultrasound for distance measurement, as an example of a distance measuring sensor. The eight obstacle detectors 68 are distributed at the front and left and right ends of the vehicle body so that the area to be explored Y is the front and both left and right sides of the vehicle body. Each obstacle detector 68 has a roughly conical area to be explored Y. Each obstacle detector 68 transmits the exploration information obtained from its exploration to the corresponding exploration information processing device 69.

[0053] Each detection information processing device 69 determines whether or not an obstacle has approached within close range of the vehicle body based on the time from the transmission to the reception of ultrasonic waves from each corresponding obstacle detector 68, and outputs this determination result to the driving suppression control unit 30D.

[0054] As a result, if an obstacle approaches the vehicle at an abnormally close distance from the front or left / right sides while the vehicle is in autonomous driving mode, the obstacle detection module 64 will detect the approach of this obstacle.

[0055] Incidentally, the obstacle detection module 64 detects an obstacle if, for example, the vehicle is driving towards a ridge under autonomous driving conditions, or if the vehicle is driving along the edge of a ridge under autonomous driving conditions, and the ridge becomes abnormally close to the vehicle. It also detects a moving object as an obstacle if it becomes abnormally close to the vehicle.

[0056] [About obstacle detectors] Each obstacle detector 65 employs a laser scanner that has a planar detection area X and a detection angle of up to approximately 270 degrees. Each obstacle detector 65 is equipped with a detection unit that detects obstacles and a processing unit that processes the detection information from the detection unit. The detection unit irradiates the detection area X with a laser beam and receives the reflected light. The processing unit determines whether or not an obstacle is approaching the vehicle at close range based on the time from irradiation to reception of the laser beam, and outputs the determination result to the driving suppression control unit 30D.

[0057] The front obstacle detector 65 has the area in front of the vehicle body set as the detection target area X. The area in front of and to the side of the main body of the vehicle is designated 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 device W is designated 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.

[0058] As shown in Figure 5, the first detection target area X1 and the second detection target area X2 are set to a range where the field ground is not detected, even if the vehicle body rolls or pitches slightly in response to the unevenness of the field during work.

[0059] As shown in Figures 1-3, Figure 4, etc., each obstacle detector 65 is mounted on a support frame that extends vertically. Here, the support frame is the front pillar 73 provided on the cabin 4.

[0060] In other words, as shown in Figure 2, each obstacle detector 65 is positioned between the outer edge of the hood 16 and the outermost position M on the vehicle body in the left-right direction. Each obstacle detector 65 is also positioned between the upper end of the hood 16 and the upper end of the front wheel 9 in the up-down direction. Furthermore, each obstacle detector 65 is positioned in the front-to-rear middle section of the vehicle body. Here, the front-to-rear middle section of the vehicle body refers to an area that extends to a certain extent front-to-rear from the front-to-rear center of the vehicle body.

[0061] Furthermore, each obstacle detector 65 is positioned between the front axle 9A of the front wheel 9 and the rear axle 10A of the rear wheel 10 in the front-rear direction. This allows the first detection target area X1 to be set so that obstacles can be detected effectively even when the vehicle is tilted on complex terrain.

[0062] As shown in Figures 5 to 7, the first detection area X1 of each obstacle detector 65 is set to be inclined in the front, back, left, and right directions with respect to the horizontal plane. To elaborate, as shown in Figure 5, the detection area X of each obstacle detector 65 is inclined to be downward at the front and upward at the rear. Furthermore, the first detection area X1 of each obstacle detector 65 is set to pass above the front of the front wheel 9. Furthermore, the first detection area X1 of each obstacle detector 65 is set to pass above the front of the weight 1A. Also, as shown in Figure 7, the first detection area X1 of each obstacle detector 65 is inclined downward from the inside of the aircraft's side to the outside of the aircraft's side.

[0063] As shown in Figures 5 and 6, the rear obstacle detector 102 has its second detection target area X2 set to the area behind the work device W at the rear of the vehicle body. The second detection target area X2 of the rear obstacle detector 102 is set to have a downward sloping angle. The second detection target area X2 is set to be wider than the width of the work device W in the left-right direction.

[0064] Here, the driving suppression control unit 30D shown in Figure 4 has a control program and the like that enables the execution of driving suppression control. Based on the discrimination results of each obstacle detector 65 and the rear obstacle detector 102, when the driving suppression control unit 30D confirms that an obstacle is approaching the vehicle at close range, it starts driving suppression control in priority to automatic driving based on the control operation of the automatic driving control unit 30C. The driving suppression control unit 30D then performs driving suppression control based on the discrimination results of each obstacle detector 65, the rear obstacle detector 102 and each detection information processing device 69.

[0065] In the driving suppression control, the driving suppression control unit 30D outputs a deceleration command to the driving control unit 30A at the start of the driving suppression control. As a result, the driving suppression control unit 30D decelerates the main transmission 32 through the control operation of the driving control unit 30A, reducing the vehicle speed from the set speed for normal driving to the set speed for collision avoidance. In this low-speed driving state, when the driving suppression control unit 30D detects an obstacle approaching within close range of the vehicle body based on the determination result of one of the detection information processing devices 69, it outputs an emergency stop command to the driving control unit 30A and the work control unit 30B. As a result, the driving suppression control unit 30D switches the forward / reverse switching device 33 to the neutral state through the control operation of the driving control unit 30A, and activates the left and right brakes through the operation of the brake operation unit 35 to brake the left and right front wheels 9 and the left and right rear wheels 10. In addition, the driving suppression control unit 30D switches the PTO clutch 34 to the disengaged state through the operation of the work control unit 30B, stopping the operation of the work device W. As a result, based on the approach of an obstacle within close range to the vehicle body, the vehicle can be stopped from moving and the operation of the work device W can be stopped quickly, thus avoiding the risk of the vehicle body coming into contact with the obstacle. In this low-speed driving state, the driving suppression control unit 30D outputs a speed increase command to the driving control unit 30A when it confirms that there are no obstacles within close range to the vehicle body based on the determination results of each obstacle detector 65, and then terminates the driving suppression control. As a result, the driving suppression control unit 30D increases the speed of the main transmission 32 based on the control operation of the driving control unit 30A, raising the vehicle speed from the set speed for contact avoidance to the set speed for normal driving, and then resumes automatic driving based on the control operation of the automatic driving control unit 30C.

[0066] 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 for capturing images of the front of the vehicle, and this camera 66 is installed at the left-right center of the front end of the upper part of the cabin 4, with an inclined position so that the shooting direction is forward and downward. One of the four surveillance cameras 66 is for capturing images of the right side of the vehicle, and these cameras 66 are installed at a predetermined distance front to back at the right end of the upper part of the cabin 4, with an inclined position so that the shooting direction is to the right and downward. One of the four surveillance cameras 66 is for capturing images of the left side of the vehicle, and these cameras 66 are installed at a predetermined distance front to back at the left end of the upper part of the cabin 4, with an inclined position so that the shooting direction is to the left and downward. One of the four surveillance cameras 66 is for capturing images of the rear of the vehicle, and this camera 66 is installed at the left-right center of the rear end of the upper part of the cabin 4, with an inclined position so that the shooting direction is to the rear and downward. This allows for comprehensive photography of the vehicle's surroundings.

[0067] The image processing device 67 shown in Figure 4 processes video signals from each surveillance camera 66 to generate images of the front of the vehicle, the right side of the vehicle, the left side of the vehicle, the rear of the vehicle, and an overhead view image as if looking down from directly above the vehicle, and transmits them to the display unit 23, etc. The display unit 23 has a control unit 23B, etc., which switches the images displayed on the liquid crystal panel 23A based on human operation of various operation switches (not shown) displayed on the liquid crystal panel 23A.

[0068] With the above configuration, during manual operation, the driver can easily visually check 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 operate the vehicle in a manner appropriate to the type of work. Furthermore, when an administrator is in the vehicle during automated operation, the administrator can easily visually check the surrounding conditions and work status of the vehicle during automated operation by displaying images from the image processing device 67 on the LCD panel 23A. If the administrator visually checks for any abnormalities in the surroundings of the vehicle or the work status during automated operation, they can promptly take appropriate action according to the type and severity of the abnormality.

[0069] As shown in Figure 4, the electronic control system 51 is equipped with a cooperative control unit 70 that automatically drives the vehicle in cooperation with other vehicles of the same specifications when the cooperative driving mode is selected by manual operation of the selection switch 50. The cooperative control unit 70 is equipped with a communication module 71 that wirelessly transmits information related to cooperative driving with other vehicles, including the vehicle's position information, to other vehicles, and a cooperative driving control unit 30E that performs cooperative driving control based on information from 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.

[0070] 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 timings, 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 pre-set target driving route for parallel driving at a set speed while performing the work appropriately. The cooperative driving control unit 30E determines whether the distance between the preceding vehicle and the vehicle in the direction of travel, and the distance between the preceding vehicle and the vehicle in the direction of parallel driving, etc., are appropriate, based on the target driving route for parallel driving of the vehicle itself, the positioning results of the positioning unit 53, the target driving route for parallel driving of other vehicles, and the position information of other vehicles, etc. If any of the distances between vehicles is not appropriate, the cooperative driving control is started, taking precedence over the automatic driving based on the control operation of the automatic driving control unit 30C, so that the distance between vehicles becomes appropriate.

[0071] In cooperative driving control, if the distance between vehicles in the direction of travel is shorter than the appropriate distance, the cooperative driving control unit 30E outputs a deceleration command to the driving control unit 30A. As a result, the cooperative driving control unit 30E decelerates the main transmission 32 through the control operation of the driving control unit 30A, restoring the distance between vehicles in the direction of travel to the appropriate distance. Then, as the distance between vehicles 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 distance between vehicles in the direction of travel at the appropriate distance.

[0072] If the distance between vehicles in the direction of travel is longer than the appropriate distance, the cooperative driving control unit 30E outputs a speed increase command to the driving control unit 30A. As a result, the cooperative driving control unit 30E activates the main transmission 32 to increase speed based on the control operation of the driving control unit 30A, restoring the distance between vehicles in the direction of travel to the appropriate distance. Then, as the distance between vehicles 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 driving and maintaining the distance between vehicles in the direction of travel at the appropriate distance.

[0073] If the distance between vehicles in the parallel driving direction is longer than the appropriate distance, the cooperative driving control unit 30E outputs a steering command to the other vehicle to the driving control unit 30A. As a result, the cooperative driving control unit 30E steers the left and right front wheels 9 toward the other vehicle through the control operation of the driving control unit 30A, restoring the distance between vehicles in the parallel driving direction to the appropriate distance. Then, as the distance between vehicles 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 direction of travel of the vehicle to the direction of normal driving and maintaining the distance between vehicles in the parallel driving direction at the appropriate distance.

[0074] If the distance between vehicles in the parallel driving direction is shorter than the appropriate distance, the cooperative driving control unit 30E outputs a steering command to the driving control unit 30A to move away from the other vehicle. As a result, the cooperative driving control unit 30E steers the left and right front wheels 9 away from the other vehicle through the control operation of the driving control unit 30A, restoring the distance between vehicles in the parallel driving direction to the appropriate distance. Then, as the distance between vehicles 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, returning the direction of travel of the vehicle to the direction of normal driving and maintaining the distance between vehicles in the parallel driving direction at the appropriate distance.

[0075] This allows the vehicle to automatically maintain an appropriate distance from other vehicles ahead, both in the direction of travel and in the direction of parallel driving.

[0076] As shown in Figures 1 to 4, the cabin 4 is equipped with a roof frame 72 that supports the roof 62, 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 front and rear intermediate parts of the roof frame 72, 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 by the left and right center pillars 74 so as to be able to open and close and swing, left and right side panels 78 that form the rear sides of the cabin 4, and a rear panel 79 that is supported by the roof frame 72 so as to be able to open and close and swing.

[0077] The left and right front pillars 73 are positioned forward of the vehicle body, relative to the center of the wheelbase L. The upper half of the left and right front pillars 73 is curved such that, in a front view, the upper part of the upper half is positioned closer to the left-right center of the vehicle body, and in a side view, the upper part of the upper half is positioned closer to the front-rear center of the vehicle body. Turn signals 100 are supported on each of the left and right front pillars 73. In addition, rearview mirrors 101, which are rotatable around a vertical axis and whose mirror surface can be adjusted forward, backward, left, and right, are supported on the left and right front pillars 73 above the turn signals 100.

[0078] 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 the rear obstacle detector 102 and the rearward-facing surveillance camera 66, etc.

[0079] [About obstacle detection devices] As shown in Figures 1, 3, and 4, each obstacle detector 68 is installed at least above the left and right front wheels 9 on the vehicle body. This ensures that, for example, even if the vehicle body rolls or pitches in response to the unevenness of the field during work, causing one of the obstacle detectors 68 to approach the ground, the distance from the ground of each obstacle detector 68 at that time can be maintained to be longer than the detection range of each obstacle detector 68.

[0080] In other words, each obstacle detector 68 is positioned at an appropriate height to avoid the risk of the field ground entering the detection range of each obstacle detector 68, even if the vehicle body rolls or pitches in response to the unevenness of the field during operation. This prevents the risk of each obstacle detector 68 mistakenly detecting the field ground as an obstacle due to the rolling or pitching of the vehicle body during operation.

[0081] The detection area Y of the obstacle detector 68 includes the first detection area Y1, the second detection area Y2, the third detection area Y3, and the fourth detection area Y4.

[0082] The obstacle detector 68 includes a pair of first obstacle detectors 68A, one on the left and one on the right, with the side of the rear end of the main body of the vehicle as the first target area Y1; a pair of second obstacle detectors 68B, one on the left and one on the right, with the side of the front-rear central part of the vehicle as the second target area Y2; a pair of third obstacle detectors 68C, one on the left and one on the right, with the side of the front-rear central part of the vehicle as the third target area Y3, which is in front of the second obstacle detectors 68B; and a pair of fourth obstacle detectors 68D, one on the left and one on the right, with the front of the vehicle as the fourth target area Y4.

[0083] As shown in Figures 1 to 3, the two first obstacle detectors 68A are mounted on the rear of the rear fender 12. To elaborate, each first obstacle detector 68A is mounted on the left and right rear fenders 12 in a position behind the rear axle 10A of the left and right rear wheels 10. Each first obstacle detector 68A is capable of detecting obstacles present in the first target area Y1. The first target area Y1 is set to extend laterally and downward from the first obstacle detectors 68A.

[0084] Two second obstacle detectors 68B are mounted on the front of the rear fender 12. Each second obstacle detector 68B is capable of detecting obstacles present in the second target area Y2. The second target area Y2 is set to extend laterally and downward from the second obstacle detectors 68B.

[0085] The two third obstacle detectors 68C are mounted on 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 the third target area Y3. The third target area Y3 is set to extend laterally and downward from the third obstacle detectors 68C.

[0086] As shown in Figures 1 to 4, of the eight obstacle detectors 68 mentioned above, the left and right pair of fourth obstacle detectors 68D are mounted on the upper and lower center of the front end of the bonnet 16, spaced apart from each other in the left-right direction. Each fourth obstacle detector 68D is capable of detecting obstacles present in the fourth search area Y4. The left and right fourth obstacle detectors 68D allow the search area Y in front of the vehicle to be widened in the left-right direction. The fourth search area Y4 is set to extend laterally downward from the fourth obstacle detectors 68D.

[0087] As shown in Figure 1, the third obstacle detector 68C and the obstacle detector 65 are located below the rearview mirror 101.

[0088] The first target area Y1 detected by the first obstacle detector 68A and the second target area X2 detected by the rear obstacle detector 102, as shown in Figures 5 and 6, are each optimally adjusted according to the type and width of the work device W.

[0089] Furthermore, to prevent the detection of the ground instead of an obstacle, a limit is set at the outer edge of the detection target area X. 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 a schematic representation for illustrative purposes.

[0090] With the above installation, the left and right sides of the rear of the vehicle body where the left and right rear fenders 12 etc. are located become the first detection 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 etc. are located become the second detection area Y2 of the left and right second obstacle detectors 68B, and the left and right sides of the front and rear center of the vehicle body where the left and right front pillars 73 etc. are located become the third detection 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 a wide area on the sides of the vehicle body that is wide in the front and rear direction into a detection area Y. As a result, obstacles located at close range to the sides of the vehicle body can be detected without fail.

[0091] As a result, based on the detection by each obstacle detector 68, it is possible to avoid the vehicle transitioning to a driving state while a moving obstacle (such as an animal or an object rolled by the wind) is approaching the stationary vehicle, and it is also possible to more reliably avoid the vehicle coming into contact with an obstacle during autonomous driving.

[0092] As shown in Figure 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 effectively detect obstacles without being obstructed by the left and right rear wheels 10.

[0093] As shown in Figures 1 to 3, the left and right third obstacle detectors 68C are mounted on the left and right front pillars 73. In other words, the left and right third obstacle detectors 68C are positioned between the left and right front wheels 9 and the left and right rear wheels 10, respectively. This allows the area between the left and right front wheels 9 and the left and right rear wheels 10 to be included in the detection area Y of the left and right third obstacle detectors 68C, and the presence or absence of obstacles 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.

[0094] As shown in Figures 1 to 4, the mounting orientation of the left-side first obstacle detector 68A is set to a left-downward orientation, with the transmitting / receiving surface facing left-downward. The mounting orientation of the right-side first obstacle detector 68A is set to a right-downward orientation, with the transmitting / receiving surface facing right-downward. The mounting orientation of the left-side second obstacle detector 68B is set to a left-facing orientation, with the transmitting / receiving surface facing left-sideward. The mounting orientation of the right-side second obstacle detector 68B is set to a right-facing orientation, with the transmitting / receiving surface facing right-sideward. The mounting orientation of the left-side third obstacle detector 68C is set to a left-downward orientation, with the transmitting / receiving surface facing left-downward. The mounting orientation of the right-side third obstacle detector 68C is set to a right-downward orientation, with the transmitting / receiving surface facing right-downward. The mounting orientations of the left and right fourth obstacle detectors 68D are each set to a forward orientation, with the transmitting / receiving surfaces facing forward.

[0095] In Figure 6, the areas indicated by the bold dashed lines represent regions where the obstacle detector 65 can detect obstacles located below a predetermined height. Conversely, the areas indicated by the thin dashed lines in Figure 6 represent regions where the obstacle detector 65 cannot detect obstacles located below a predetermined height.

[0096] As shown in Figures 5 and 6, the first target area Y1 of the first obstacle detector 68A, the second target area Y2 of the second obstacle detector 68B, and the third target area Y3 of the third obstacle detector 68C cover the areas on the sides of the vehicle that are not included in the target area X of the obstacle detector 65 (areas that are blind spots for the obstacle detector 65), and are capable of detecting obstacles.

[0097] In this way, by covering the areas not included in the detection area X of each obstacle detector 65 with the detection area Y of each obstacle explorer 68, it is possible to reduce the blind spots around the vehicle where obstacles are not detected. As a result, obstacles around the vehicle can be detected with high accuracy while driving, and the vehicle's movement can be stopped before it comes into contact with an obstacle. Furthermore, if a moving obstacle (such as an animal or something that moves in the wind) approaches the vehicle while it is stopped, the system can accurately detect the obstacle and prevent the vehicle from transitioning from a stopped state to a moving state, thereby avoiding problems such as the vehicle running over the obstacle with the vehicle's running gear 2 or work device W.

[0098] [Another embodiment] The following describes alternative embodiments that modify the above embodiments. Multiple alternative embodiments can be combined and applied to the above embodiments, provided that no inconsistencies arise. However, the scope of the present invention is not limited to the contents shown in each embodiment.

[0099] (1) The obstacle detectors 65 do not necessarily have to be provided in pairs, one on the left and one on the right. Specifically, the first detection target area X1 by the left obstacle detector 65 and the first detection target area X1 by the right obstacle detector 65 may be asymmetrical. Also, the obstacle detector 65 may be provided on only one side, either the left or the right.

[0100] (2) The obstacle detector 65 does not have to be mounted on the front pillar 73. For example, the obstacle detector 65 may be mounted on the rearview mirror 101. Alternatively, for example, the obstacle detector 65 may be mounted on the frame near the turn signal 100. By placing 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.

[0101] (3) Instead of the cabin 4, a gate-shaped locating frame may be provided, located behind the driver's seat 22, having a pair of left and right support columns and a beam connecting the upper ends of the left and right support columns. In this case, the obstacle detector 65 may be attached to the locating frame. Specifically, the obstacle detector 65 can be attached to the support columns of the locating frame or to the beam of the locating frame.

[0102] (4) An extension frame may be provided in the driver's compartment 17, extending from the tip of the platform where the passenger's feet are located to the bonnet 16. In this case, the obstacle detector 65 can be attached to the extension frame.

[0103] (5) The first obstacle detector 68A and the second obstacle detector 68B may be attached to a component other than the rear fender 12.

[0104] (6) The obstacle detector 65 may be a device other than a laser scanner.

[0105] (7) The obstacle detector 65 may be positioned at a location that is offset in the left-right direction from the space between the outer edge of the hood 16 and the outermost position M on the main body of the vehicle.

[0106] (8) The obstacle detector 65 may be located at a location other than the front-to-rear intermediate part of the vehicle body.

[0107] (9) The first detection target area X1 of the obstacle detector 65 may be set to be tilted only in the front-to-back direction with respect to the horizontal plane, or to be tilted only in the left-to-right direction with respect to the horizontal plane.

[0108] (10) The obstacle detector 68 may be a device other than an ultrasonic sensor. For example, an infrared rangefinder or the like may be used as the obstacle detector 68.

[0109] (11) The left and right first obstacle detectors 68A may be positioned above the headlights 107 at the front end of the bonnet 16.

[0110] (12) The number of obstacle detectors 68 may be 10 or more, or if the overall length of the work vehicle is short, the number of obstacle detectors 68 may be 6 or less.

[0111] (13) The left and right rear wheels 10 may be replaced with left and right crawlers in a semi-crawler configuration.

[0112] (14) The system may be configured as a full crawler specification, in which left and right crawlers are provided instead of the left and right front wheels 9 and left and right rear wheels 10.

[0113] (15) It may also be a two-wheel drive system in which either the left or right front wheels 9 or the left or right rear wheels 10 are driven.

[0114] (16) The engine 6 may be replaced with an electric motor to create an electric configuration.

[0115] (17) It may be configured as a hybrid specification equipped with an engine 6 and an electric motor. [Industrial applicability]

[0116] The present invention can be used in work vehicles equipped with an electronically controlled system for automatic driving that drives the vehicle body automatically. For example, in addition to the tractor mentioned above, it can be used in riding lawnmowers, combine harvesters, riding rice transplanters, and wheel loaders, etc. [Explanation of symbols]

[0117] 1A: Weight 3: Driving Unit 4: Cabin 9: Front wheel 9A: Front axle 10: Rear wheel 10A: Rear axle 16: Hood 65: Obstacle Detector 68: Obstacle detector X: Detection target area Y: Area to be explored

Claims

[Claim 1] The car body and, A lifting device capable of attaching a work device to the vehicle body, A cabin provided on the aforementioned vehicle body, A bonnet provided on the front side of the cabin, Obstacle detectors and obstacle explorers, A tractor equipped with, A tractor is provided with an obstacle detector that detects the rear of the cabin and behind the lifting device, a first obstacle detector is provided on the side of the cabin door, and a plurality of second obstacle detectors are provided on the front of the hood.

Images