Work vehicle

Abstract

To appropriately measure a distance to an object to be measured by a distance sensor while preventing the deterioration of measurement accuracy and the impossibility of measurement itself.SOLUTION: A work vehicle includes a traveling vehicle body having a traveling part, a work device connected to a rear part of the traveling vehicle body, a distance sensor (rear distance sensor 102) capable of detecting an object on the rear side of the traveling vehicle body, and a camera (rear camera 109) capable of imaging the rear side of the traveling vehicle body.SELECTED DRAWING: Figure 9

Description

[Technical Field]

[0001] The present invention relates to a work vehicle equipped with a traveling machine body having a traveling section. [Background technology]

[0002] In a work vehicle such as the one described above, a hood is provided at the front of the traveling body, a driver's seat is provided behind the hood, and a distance sensor is provided to detect unevenness in the ground (see, for example, Patent Document 1).

[0003] The work vehicle described in Patent Document 1 is provided with a support arm at the front end of the hood that can rotate freely around an axis along the left-right direction of the traveling body, and a distance sensor is provided at the tip of the support arm. The distance sensor is an ultrasonic distance sensor or an infrared sensor that can measure the distance between the set position of the support arm and the ground. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] Japanese Patent Application Laid-Open No. 2015-189439 Summary of the Invention [Problem to be solved by the invention]

[0005] The work vehicle described in Patent Document 1 uses a distance sensor that can measure the distance to the object to be measured in two dimensions, so in order to accurately measure the distance to the object to be measured, it is preferable to install the distance sensor at a position closer to the ground, which is the object to be measured.

[0006] Therefore, in the work vehicle described in Patent Document 1, the distance sensor is installed at the tip of a support arm provided at the front end of the traveling body, thereby installing the distance sensor at a position closer to the ground. However, if the distance sensor is installed at a position closer to the ground, mud, water, etc. will be scattered and adhere to the distance sensor while the work vehicle is traveling, which may result in a decrease in measurement accuracy or may even make it impossible for the distance sensor to perform measurement.

[0007] In view of this situation, the main objective of the present invention is to provide a work vehicle that can properly measure the distance to an object to be measured using a distance sensor while preventing a decrease in measurement accuracy or the inability to perform measurement at all. [Means for solving the problem]

[0008] A work vehicle according to one aspect of the present invention comprises a running body having a running section, a work device connected to the rear of the running body, a distance sensor capable of detecting objects on the rear side of the running body, and a camera capable of capturing images of the rear side of the running body. [Brief explanation of the drawings]

[0009] [Figure 1] Diagram showing the schematic configuration of an automated driving system [Figure 2] Block diagram showing the general configuration of the automated driving system [Figure 3] A diagram showing the target driving route [Figure 4] A diagram showing the upper part of the tractor as seen from the front. [Figure 5] A diagram showing the upper part of the tractor as seen from behind. [Figure 6] A side view showing the antenna unit and the front distance sensor in the use position. [Figure 7] FIG. 10 is a perspective view showing a support structure for the antenna unit and the front distance sensor. [Figure 8] FIG. 10 is a side view showing the antenna unit and the front distance sensor in the non-use position; [Figure 9]1 is a diagram showing a roof, an antenna unit, a front distance sensor, and a rear distance sensor as viewed from the side in a use position and a non-use position; [Figure 10] FIG. 10 is a perspective view showing a support structure for a rear distance sensor. [Figure 11] A diagram showing the measurement ranges of the front distance sensor and the rear distance sensor in a side view. [Figure 12] A diagram showing the measurement ranges of the front distance sensor, rear distance sensor, and sonar in a plan view. [Figure 13] A diagram showing a 3D image generated from the measurement results of the front distance sensor. [Figure 14] FIG. 10 is a diagram showing a three-dimensional image generated from the measurement results of the rear distance sensor when the work implement is positioned in the lowered position. [Figure 15] FIG. 10 is a diagram showing a three-dimensional image generated from the measurement results of the rear distance sensor when the work implement is positioned in the raised position. [Figure 16] A perspective view showing the left sonar mounting structure DETAILED DESCRIPTION OF THE INVENTION

[0010] An embodiment in which a work vehicle according to the present invention is applied to an automated driving system will be described with reference to the drawings. In this automatic driving system, as shown in FIG. 1, a tractor 1 is applied as the work vehicle according to the present invention, but other work vehicles such as riding rice transplanters, combine harvesters, riding mowers, wheel loaders, snowplows, etc., as well as unmanned work vehicles such as unmanned mowers, etc., can also be applied.

[0011] As shown in Figures 1 and 2, this automatic driving system includes an automatic driving unit 2 mounted on a tractor 1, and a mobile communication terminal 3 configured to communicate with the automatic driving unit 2. The mobile communication terminal 3 can be a tablet-type personal computer or a smartphone having a touch-operable display unit 51 (e.g., a liquid crystal panel) or the like.

[0012] The tractor 1 is equipped with a running body 7 having left and right front wheels 5 (corresponding to the running part) that function as drivable steering wheels, and left and right rear wheels 6 (corresponding to the running part). A bonnet 8 is disposed in front of the running body 7, and an electronically controlled diesel engine (hereinafter referred to as the engine) 9 equipped with a common rail system is provided inside the bonnet 8. A cabin 10 that forms a boarding type driver's section is provided behind the bonnet 8 of the running body 7.

[0013] The tractor 1 can be configured for rotary tillage by connecting a rotary tiller, which is an example of a working implement 12, to the rear of the traveling body 7 via a three-point linkage mechanism 11 so that it can be raised, lowered, and rolled. Instead of a rotary tiller, the rear of the tractor 1 can be connected to a working implement 12 such as a plow, sowing implement, or spraying implement.

[0014] As shown in Figure 2, the tractor 1 is equipped with an electronically controlled transmission 13 that changes the speed of power from the engine 9, a fully hydraulic power steering mechanism 14 that steers the left and right front wheels 5, left and right side brakes (not shown) that brake the left and right rear wheels 6, an electronically controlled brake operation mechanism 15 that enables hydraulic operation of the left and right side brakes, a work clutch (not shown) that interrupts transmission of power to the work implement 12 such as a rotary tiller, an electronically controlled clutch operation mechanism 16 that enables hydraulic operation of the work clutch, an electronically hydraulically controlled lift drive mechanism 17 that drives the work implement 12 such as a rotary tiller to lift and lower, an on-board electronic control unit 18 that has various control programs related to the automatic driving of the tractor 1, a vehicle speed sensor 19 that detects the vehicle speed of the tractor 1, a steering angle sensor 20 that detects the steering angle of the front wheels 5, and a positioning unit 21 that measures the current position and current direction of the tractor 1.

[0015] The engine 9 may be an electronically controlled gasoline engine equipped with an electronic governor. The transmission 13 may be a hydromechanical continuously variable transmission (HMT), a hydrostatic continuously variable transmission (HST), or a belt-type continuously variable transmission. The power steering mechanism 14 may be an electric power steering mechanism 14 equipped with an electric motor.

[0016] As shown in FIGS. 4 and 5 , the cabin 10 is configured in a box shape including a cabin frame 31 forming the framework of the cabin 10, a windshield 32 covering the front side, a rear glass 33 covering the rear side, a pair of left and right doors 34 (see FIG. 1 ) that can swing open and close about axes along the vertical direction, and a roof 35 on the ceiling side. The cabin frame 31 includes a pair of left and right front support columns 36 located at the front end and a pair of left and right rear support columns 37 located at the rear end. In a plan view, the front support columns 36 are located at both left and right corners on the front side, and the rear support columns 37 are located at both left and right corners on the rear side. The cabin frame 31 is supported on the traveling vehicle body 7 via vibration-damping members such as elastic bodies, and the cabin 10 is provided with vibration-damping measures in place to prevent vibrations from the traveling vehicle body 7 and the like from being transmitted to the cabin 10.

[0017] As shown in Fig. 1, the interior of the cabin 10 is equipped with a steering wheel 38 that enables manual steering of the left and right front wheels 5 via a power steering mechanism 14 (see Fig. 2), a driver's seat 39 for passengers, a touch panel display unit, various operating tools, etc. On both sides of the front portion of the cabin 10, there are provided boarding and alighting steps 41 that serve as boarding and alighting points to the cabin 10 (driver's seat 39).

[0018] As shown in Figure 2, the on-board electronic control unit 18 includes a transmission control unit 181 that controls the operation of the transmission 13, a braking control unit 182 that controls the operation of the left and right side brakes, an implement control unit 183 that controls the operation of the implement 12 such as a rotary tiller, a steering angle setting unit 184 that sets the target steering angle of the left and right front wheels 5 during automatic driving and outputs it to the power steering mechanism 14, and a non-volatile on-board memory unit 185 that stores a pre-set target driving route P for automatic driving (see Figure 3, for example).

[0019] As shown in FIG. 2, the positioning unit 21 includes a satellite navigation device 22 that measures the current position and current orientation of the tractor 1 using a global positioning system (GPS), which is an example of a navigation satellite system (NSS), and an inertial measurement unit (IMU) 23 that has a three-axis gyroscope, a three-directional acceleration sensor, and the like and measures the attitude, orientation, and the like of the tractor 1. Positioning methods that use GPS include differential GPS (DGPS: relative positioning method) and real-time kinematic GPS (RTK-GPS: interferometric positioning method). In this embodiment, RTK-GPS, which is suitable for positioning a moving object, is adopted. For this reason, reference stations 4 that enable positioning by RTK-GPS are installed at known positions around the field, as shown in FIGS. 1 and 2.

[0020] As shown in Fig. 2, the tractor 1 and the reference station 4 are each equipped with a GPS antenna 24, 61 that receives radio waves transmitted from a GPS satellite 71 (see Fig. 1), and communication modules 25, 62 that enable wireless communication of various data including positioning data between the tractor 1 and the reference station 4. This allows the satellite navigation device 22 to measure the current position and current orientation of the tractor 1 with high accuracy based on the positioning data obtained by the tractor-side GPS antenna 24 receiving radio waves from the GPS satellite 71 and the positioning data obtained by the base station-side GPS antenna 61 receiving radio waves from the GPS satellite 71. Furthermore, the positioning unit 21 is equipped with the satellite navigation device 22 and the inertial measurement unit 23, and is therefore able to measure the current position, current orientation, and attitude angles (yaw angle, roll angle, pitch angle) of the tractor 1 with high accuracy.

[0021] The GPS antenna 24, communication module 25, and inertial measurement unit 23 provided in the tractor 1 are housed in an antenna unit 80, as shown in Fig. 1. The antenna unit 80 is disposed at an upper position on the front side of the cabin 10.

[0022] 2, the mobile communication terminal 3 is equipped with a terminal electronic control unit 52 having various control programs for controlling the operation of the display unit 51, etc., and a communication module 55 that enables wireless communication of various data including positioning data with the communication module 25 on the tractor side. The terminal electronic control unit 52 has a driving route generation unit 53 that generates a target driving route P (see FIG. 3, for example) for driving guidance to cause the tractor 1 to automatically drive, and a non-volatile terminal storage unit 54 that stores various input data input by the user, the target driving route P generated by the driving route generation unit 53, etc.

[0023] When the travel route generation unit 53 generates the target travel route P, a user such as a driver or manager inputs vehicle body data such as the type and model of the work vehicle or work implement 12 according to input guidance for setting the target travel route displayed on the display unit 51 of the mobile communication terminal 3, and the input vehicle body data is stored in the terminal memory unit 54. The travel area S (see FIG. 3 ) for which the target travel route P is to be generated is a farm field, and the terminal electronic control unit 52 of the mobile communication terminal 3 acquires farm field data including the shape and position of the field and stores it in the terminal memory unit 54.

[0024] To explain how field data is acquired, when a user or the like actually drives the tractor 1, the terminal electronic control unit 52 can acquire position information for identifying the shape, position, etc. of the field from the current position of the tractor 1 acquired by the positioning unit 21. The terminal electronic control unit 52 identifies the shape and position of the field from the acquired position information, and acquires field data including the travel area S identified from the identified shape and position of the field. Figure 3 shows an example in which a rectangular travel area S has been identified.

[0025] When field data including the shape and position of the identified field is stored in the terminal memory unit 54, the driving path generation unit 53 generates a target driving path P using the field data and vehicle data stored in the terminal memory unit 54.

[0026] As shown in FIG. 3 , the travel path generating unit 53 divides the travel area S into a central area R1 and an outer peripheral area R2. The central area R1 is set in the center of the travel area S and is a round-trip work area where the tractor 1 automatically travels in a round-trip direction ahead of the central area R1 to perform a predetermined task (e.g., plowing, etc.). The outer peripheral area R2 is set around the central area R1 and is a circular work area where the tractor 1 automatically travels in a circular direction following the central area R1 to perform a predetermined task. The travel path generating unit 53 determines, for example, a turning space required for the tractor 1 to turn around the edge of the field from the turning radius, the front-to-rear width, and the left-to-right width of the tractor 1, etc., included in the vehicle body data. The travel path generating unit 53 divides the travel area S into the central area R1 and the outer peripheral area R2 so as to ensure the determined space around the periphery of the central area R1.

[0027] As shown in FIG. 3, the travel path generation unit 53 generates a target travel path P using vehicle data, field data, and the like. For example, the target travel path P includes multiple work paths P1 that are set in parallel in the central region R1 and have the same straight-line distance and are spaced apart at a fixed distance corresponding to the work width, a connecting path P2 that connects the start and end of adjacent work paths P1, and a circular path P3 (shown by a dotted line in the figure) that circles around in the outer peripheral region R2. The multiple work paths P1 are paths along which the tractor 1 performs a predetermined task while traveling straight. The connecting path P2 is a U-turn path that allows the tractor 1 to change its traveling direction 180 degrees without performing the predetermined task, and connects the end of a work path P1 to the start of the next adjacent work path P1. The circular path P3 is a path along which the tractor 1 performs a predetermined task while traveling around in the outer peripheral region R2. The circular path P3 changes the traveling direction of the tractor 1 by 90 degrees by switching the tractor 1 between forward traveling and reverse traveling at positions corresponding to the four corners of the traveling area S. Incidentally, the target traveling path P shown in Fig. 3 is merely an example, and the type of target traveling path to be set can be changed as appropriate.

[0028] The target driving route P generated by the driving route generation unit 53 can be displayed on the display unit 51, and is stored in the terminal storage unit 54 as route data associated with vehicle data, farm field data, etc. The route data includes the azimuth angle of the target driving route P, and a set engine rotation speed and target driving speed set according to the driving mode of the tractor 1 on the target driving route P, etc.

[0029] In this way, when the travel route generation unit 53 generates the target travel route P, the terminal electronic control unit 52 transfers the route data from the mobile communication terminal 3 to the tractor 1, allowing the on-board electronic control unit 18 of the tractor 1 to acquire the route data. Based on the acquired route data, the on-board electronic control unit 18 can automatically drive the tractor 1 along the target travel route P while acquiring its own current position (the current position of the tractor 1) using the positioning unit 21. The current position of the tractor 1 acquired by the positioning unit 21 is transmitted from the tractor 1 to the mobile communication terminal 3 in real time (for example, every few seconds), and the current position of the tractor 1 is known by the mobile communication terminal 3.

[0030] Regarding the transfer of route data, before the tractor 1 starts autonomous driving, the entire route data can be transferred all at once from the terminal electronic control unit 52 to the on-board electronic control unit 18. Also, for example, route data including the target driving route P can be divided into multiple route segments of predetermined distances each with a small amount of data. In this case, before the tractor 1 starts autonomous driving, only the initial route segment of the route data is transferred from the terminal electronic control unit 52 to the on-board electronic control unit 18. After the start of autonomous driving, each time the tractor 1 reaches a route acquisition point set according to the amount of data, etc., route data for only the subsequent route segment corresponding to that point may be transferred from the terminal electronic control unit 52 to the on-board electronic control unit 18.

[0031] When starting automatic driving of the tractor 1, for example, a user or the like moves the tractor 1 to a start point, and once various automatic driving start conditions are satisfied, the user operates the display unit 51 of the mobile communication terminal 3 to instruct the start of automatic driving, and the mobile communication terminal 3 then transmits an instruction to start automatic driving to the tractor 1. As a result, in the tractor 1, the on-board electronic control unit 18 receives the instruction to start automatic driving, and starts automatic driving control to automatically drive the tractor 1 along the target driving route P while acquiring its own current position (the current position of the tractor 1) using the positioning unit 21.

[0032] The automatic driving control includes automatic speed change control that automatically controls the operation of the transmission 13, automatic braking control that automatically controls the operation of the brake operating mechanism 15, automatic steering control that automatically steers the left and right front wheels 5, and automatic work control that automatically controls the operation of work implements 12 such as rotary tillers.

[0033] In automatic transmission control, the transmission control unit 181 automatically controls the operation of the transmission 13 based on route data of the target driving route P including the target driving speed, the output of the positioning unit 21, and the output of the vehicle speed sensor 19, so that the target driving speed set in accordance with the driving mode of the tractor 1 on the target driving route P is obtained as the vehicle speed of the tractor 1.

[0034] In automatic braking control, the braking control unit 182 automatically controls the operation of the brake operating mechanism 15 based on the target driving route P and the output of the positioning unit 21 so that the left and right side brakes properly brake the left and right rear wheels 6 in the braking area included in the route data of the target driving route P.

[0035] In the automatic steering control, the steering angle setting unit 184 determines and sets target steering angles for the left and right front wheels 5 based on the route data of the target driving route P and the output of the positioning unit 21 so that the tractor 1 automatically drives along the target driving route P, and outputs the set target steering angles to the power steering mechanism 14. Based on the target steering angles and the output of the steering angle sensor 20, the power steering mechanism 14 automatically steers the left and right front wheels 5 so that the target steering angles are obtained as the steering angles of the left and right front wheels 5.

[0036] In the automatic control for work, the work implement control unit 183 automatically controls the operation of the clutch operating mechanism 16 and the lifting drive mechanism 17 based on the route data of the target travel route P and the output of the positioning unit 21 so that a predetermined work (e.g., plowing work) by the work implement 12 is started as the tractor 1 reaches a work start point such as the beginning of the work route P1 (e.g., see Figure 3), and the predetermined work by the work implement 12 is stopped as the tractor 1 reaches a work end point such as the end of the work route P1 (e.g., see Figure 3).

[0037] In this way, in the tractor 1, the automatic driving unit 2 is composed of a transmission 13, a power steering mechanism 14, a brake operating mechanism 15, a clutch operating mechanism 16, a lifting drive mechanism 17, an on-board electronic control unit 18, a vehicle speed sensor 19, a steering angle sensor 20, a positioning unit 21, and a communication module 25, etc.

[0038] In this embodiment, not only can the tractor 1 be automatically driven without a user or the like riding in the cabin 10, but it is also possible to automatically drive the tractor 1 with a user or the like riding in the cabin 10. Therefore, not only can the tractor 1 be automatically driven along the target driving route P by automatic driving control by the on-board electronic control unit 18 without a user or the like riding in the cabin 10, but even when a user or the like is riding in the cabin 10, the tractor 1 can be automatically driven along the target driving route P by automatic driving control by the on-board electronic control unit 18.

[0039] When a user or the like is on board the cabin 10, the on-board electronic control unit 18 can switch between an automatic driving state in which the tractor 1 is driven automatically and a manual driving state in which the tractor 1 is driven based on the driving of the user or the like. Thus, while the tractor is automatically driving along the target driving path P in the automatic driving state, the automatic driving state can be switched to the manual driving state, and conversely, while the tractor is driving in the manual driving state, the manual driving state can be switched to the automatic driving state. To switch between the manual driving state and the automatic driving state, for example, a switching operation unit for switching between the automatic driving state and the manual driving state can be provided near the driver's seat 39, and the switching operation unit can be displayed on the display unit 51 of the mobile communication terminal 3. Furthermore, when the user operates the steering wheel 38 during automatic driving control by the on-board electronic control unit 18, the automatic driving state can be switched to the manual driving state.

[0040] 1 and 2, the tractor 1 is equipped with an obstacle detection system 100 for detecting obstacles around the tractor 1 (traveling body 7) and avoiding collision with the obstacles. The obstacle detection system 100 is equipped with a plurality of distance sensors 101, 102 that can measure the distance to a measurement object in three dimensions using lasers, a plurality of sonars 103-106 that can measure the distance to the measurement object using ultrasonic waves, and an obstacle control unit 107 that performs obstacle control to control the tractor 1 so as to avoid collision with obstacles based on the measurement information from the distance sensors 101, 102 and the sonars 103-106.

[0041] The obstacle control unit 107 is provided in an on-board electronic control unit 18. The on-board electronic control unit 18 is communicably connected to an engine electronic control unit included in the common rail system, distance sensors 101 and 102, sonars 103 to 106, and the like via a CAN (Controller Area Network).

[0042] The distance sensors 101 and 102 measure the distance to the object (time of flight) from the round-trip time it takes for a laser beam (e.g., pulsed near-infrared laser beam) to hit the object and bounce back. The distance sensors 101 and 102 measure the distance to the object in three dimensions by scanning the laser beam vertically and horizontally at high speed and sequentially measuring the distance to the object at each scanning angle. The distance sensors 101 and 102 repeatedly measure the distance to the object within their measurement range in real time. When an object that serves as the object to be measured is present within their measurement range, the distance sensors 101 and 102 detect the object as an obstacle and measure the direction in which the obstacle exists and the distance to the obstacle. The distance sensors 101 and 102 are configured to generate a three-dimensional image from the measurement results and output it to an external device. The three-dimensional image generated from the measurement results of the distance sensors 101, 102 can be displayed on a display device such as the display unit of the tractor 1 or the display unit 51 of the mobile communication terminal 3, allowing a user or the like to visually confirm the presence or absence of an obstacle. Incidentally, in the three-dimensional image, distances in the near and far directions can be indicated using, for example, colors or the like.

[0043] As shown in Figures 11 and 12, the distance sensors 101, 102 include a front distance sensor 101 that has a measurement range C in front of the tractor 1 (traveling body 7) and detects obstacles in that measurement range C, and a rear distance sensor 102 that has a measurement range D in the rear of the tractor 1 (traveling body 7) and detects obstacles in that measurement range D.

[0044] The front distance sensor 101 and rear distance sensor 102 will be described below, in the order of the support structure of the front distance sensor 101, the support structure of the rear distance sensor 102, the measurement range C of the front distance sensor 101, and the measurement range D of the rear distance sensor 102.

[0045] The support structure of the front distance sensor 101 will be described. As shown in Figures 1 and 7, the front distance sensor 101 is attached to the bottom of the antenna unit 80, which is located at the upper position on the front side of the cabin 10. Therefore, we will first explain the support structure of the antenna unit 80, and then explain the attachment structure of the front distance sensor 101 to the bottom of the antenna unit 80.

[0046] As shown in FIGS. 4, 6, and 7, the antenna unit 80 is attached to a pipe-shaped antenna unit support stay 81 that extends the entire length of the cabin 10 in the left-right direction of the traveling body 7. The antenna unit 80 is disposed at a position corresponding to the center of the cabin 10 in the left-right direction of the traveling body 7. The antenna unit support stay 81 is fixedly connected across left and right mirror mounting portions 45 located diagonally forward of the cabin 10. The mirror mounting portions 45 include a mirror mounting base 46 fixed to the front support column 36, a mirror mounting bracket 47 fixed to the mirror mounting base 46, and a mirror mounting arm 48 that is rotatable by a hinge portion 49 provided on the mirror mounting bracket 47. As shown in FIG. 7, the antenna unit support stay 81 is formed in a bridge shape with both left and right end portions curved downward. Both left and right end portions of the antenna unit support stay 81 are fixedly connected to the upper end portions of the mirror mounting bracket 47 via a first mounting plate 201. 6 and 7, a horizontal mounting surface is formed at the upper end portion of the mirror mounting bracket 47, and a horizontal mounting surface is also formed at the lower end portion of the first mounting plate 201. By fastening the two mounting surfaces together with connecting devices 50 such as bolts and nuts while overlapping each other, the antenna unit support stay 81 is fixedly connected in a position extending horizontally. The antenna unit 80 is supported by the front support pillar 36 that constitutes the cabin frame 31 via the antenna unit support stay 81 and the mirror mounting portion 45, so that the antenna unit 80 is firmly supported while preventing the transmission of vibrations to the antenna unit 80, etc.

[0047] As for the mounting structure of the antenna unit 80 to the antenna unit support stay 81, as shown in Figures 6 and 7, the antenna unit 80 is attached to the antenna unit support stay 81 by fastening a second mounting plate 202 fixed to the antenna unit 80 side and a third mounting plate 203 fixed to the antenna unit support stay 81 side with connecting devices 50 such as bolts and nuts.

[0048] As shown in Fig. 7, a pair of second mounting plates 202 are provided on the left and right sides of the traveling body 7, spaced a predetermined distance apart in the left-right direction. The second mounting plate 202 is configured as an L-shaped plate having a stay-side mounting portion 202b extending downward from the outer end of a unit-side mounting portion 202a extending in the left-right direction. The second mounting plate 202 is attached such that the unit-side mounting portion 202a is fixedly connected to the bottom of the antenna unit 80 by a connector 50 or the like, and the stay-side mounting portion 202b extends downward. Although not shown, the stay-side mounting portion 202b of the second mounting plate 202 has a pair of front and rear circular holes formed therein for connection by a connector or the like.

[0049] 6 and 7, the third mounting plate 203 is configured as an L-shaped plate whose front portion extends downward further than its rear portion. Similar to the second mounting plate 202, a pair of third mounting plates 203 are provided on the left and right sides at a predetermined interval in the left-right direction of the traveling body 7. The third mounting plate 203 is attached such that the lower edge of the rear portion is fixedly connected to the upper part of the antenna unit support stay 81 by welding or the like, and the front portion is located forward of the antenna unit support stay 81. The third mounting plate 203 has an elongated slot 203a that extends in the front-to-rear direction of the traveling body 7 from the front portion to the rear portion, and a round hole 203b for connection formed on the lower side of the front portion.

[0050] When attaching the antenna unit 80 to the antenna unit support stay 81, as shown in Figures 6 and 7, the antenna unit 80 is placed above the antenna unit support stay 81 and positioned in the use position where the antenna of the communication module 25 extends upward. The second mounting plate 202 and the third mounting plate 203 are overlapped with each other in a state where the second mounting plate 202 is positioned inward of the third mounting plate 203 so that the front and rear round holes in the stay-side mounting portion 202b of the second mounting plate 202 align with the front and rear ends of the elongated hole 203a of the third mounting plate 203. The antenna unit 80 can be attached to the antenna unit support stay 81 in the use position by inserting and fastening the connectors 50 through the front and rear round holes of the second mounting plate 202 and the elongated hole 203a of the third mounting plate 203. At this time, the points corresponding to the front end and rear end of the long hole 203a are set as connection points by the connector 50, and a total of four points, namely the front and rear portions of each of the pair of left and right second mounting plates 202 and third mounting plates 203, are connection points by the connector 50.

[0051] The antenna unit 80 is configured to be freely attached to the antenna unit support stay 81 not only in the use position as shown in Figure 6, but also in the non-use position as shown in Figure 8, in which the antenna unit 80 is positioned forward of the antenna unit support stay 81 and the antenna of the communication module 25 extends forward.

[0052] 8, when attaching the antenna unit 80 to the antenna unit support stay 81 in the non-use position, the antenna unit 80 is positioned in the non-use position, and the second mounting plate 202 and the third mounting plate 203 are overlapped with each other in a state in which the second mounting plate 202 is positioned inward of the third mounting plate 203 so that the front and rear round holes in the stay-side mounting portion 202b of the second mounting plate 202 are aligned with the round hole 203b and the front end of the elongated hole 203a of the third mounting plate 203. The connector 50 is inserted through the front round hole in the stay-side mounting portion 202b of the second mounting plate 202 and the round hole 203b of the third mounting plate 203, and also through the rear round hole in the stay-side mounting portion 202b of the second mounting plate 202 and the front end of the elongated hole 203a and fastened, thereby attaching the antenna unit 80 to the antenna unit support stay 81 in the non-use position.

[0053] For example, when changing the antenna unit 80 from the use position (see FIG. 6) to the non-use position (see FIG. 8), as shown in FIG. 6, the connector 50 located at the front end of the elongated hole 203a of the third mounting plate 203 is removed, and the connector 50 located at the rear end of the elongated hole 203a of the third mounting plate 203 is loosened and kept inserted into the elongated hole 203a. The connector 50 is moved forward along the elongated hole 203a from the rear end to the front end, and the antenna unit 80 is hung down forward and downward with the connector 50 as a pivot axis, thereby changing the position of the antenna unit 80 to the non-use position as shown in FIG. Therefore, the connector 50 can be inserted through the round hole on the front side of the second mounting plate 202 and the round hole 203b of the third mounting plate 203, and can also be inserted through the round hole on the rear side of the second mounting plate 202 and the front end of the long hole 203a to fasten them together, allowing the antenna unit 80 to be moved from the use position to the non-use position.

[0054] When the antenna unit 80 is attached in the use position, as shown in FIG. 9(a), a portion of the antenna unit 80 protrudes upward from the highest level line Z that passes through the highest portion 35a of the roof 35, allowing the antenna of the communication module 25 to be positioned higher, enabling appropriate wireless communication of the communication module 25. In contrast, when the antenna unit 80 is attached in the non-use position, as shown in FIG. 9(b), the upper end of the antenna unit 80 is positioned at the same height as the highest level line Z or lower than the highest level line Z. This prevents the antenna unit 80 from protruding above the highest level line Z when transporting the tractor 1 or storing the tractor 1 in a storage location such as a barn, preventing the antenna unit 80 from getting in the way or being damaged by coming into contact with obstacles, etc.

[0055] As shown in FIG. 7 , the front distance sensor 101 is attached to the bottom of the antenna unit 80 by fastening the fourth and fifth mounting plates 204 and 205 with connectors 50 such as bolts and nuts. The fourth mounting plate 204 has a mounting surface 204a extending in the left-right direction, with both ends of the mounting surface 204a extending downward to form a bridge shape. The fifth mounting plate 205 has a pair of left and right mounting surfaces 205a facing each other in the left-right direction, with the upper ends of the mounting surfaces 205a connected to each other to form a bridge shape. The mounting surface 204a of the fourth mounting plate 204 is fixedly connected to the bottom of the antenna unit 80 with the connector 50. A front portion of the fourth mounting plate 204 and a rear portion of the fifth mounting plate 205 are fixedly connected with the connector 50. A pair of left and right mounting surface portions 205a of the fifth mounting plate 205 are fixedly connected to both lateral sides of the front distance sensor 101 by connectors 50. The front distance sensor 101 is attached in a state where it is sandwiched between the left and right mounting surface portions 205a of the fifth mounting plate 205 in the left-right direction.

[0056] As shown in FIG. 7 , the front distance sensor 101 is configured to be detachably attached to the antenna unit 80 via a fourth mounting plate 204 and a fifth mounting plate 205. The front distance sensor 101 can be installed later, or the front distance sensor 101 can be removed alone. The antenna unit 80 is also configured to be detachably attached to the mirror mounting portion 45 via the antenna unit support stay 81, so the front distance sensor 101 can be attached and detached to the traveling body 7 by itself, or can be attached and detached to the traveling body 7 together with the antenna unit 80. The front distance sensor 101 uses the antenna unit support stay 81 that supports the antenna unit 80 as a common support stay, and like the antenna unit 80, is firmly supported while preventing the transmission of vibrations to the front distance sensor 101.

[0057] Since the front distance sensor 101 is integrally provided with the antenna unit 80, by changing the position of the antenna unit 80 between the use position and the non-use position, the front distance sensor 101 can also be freely changed between the use position where it faces forward of the running body 7 and is used to detect obstacles in front of the running body 7, as shown in Figure 6, and the non-use position where it faces downward and is not used to detect obstacles, as shown in Figure 8.

[0058] When the front distance sensor 101 is in the use position, as shown in FIGS. 6 and 9(a), the front distance sensor 101 is disposed at a position corresponding to the roof 35, higher in the vertical direction than the boarding step 41 (see FIG. 1), which is the boarding and alighting point to the cabin 10 (driver's seat 39). The front distance sensor 101 is attached in a forward-leaning position, with the sensor positioned lower as it approaches the front. The front distance sensor 101 is configured to measure the distance by looking down at the front side of the traveling body 7 from diagonally above. The antenna unit support stay 81 is disposed at a position overlapping the front end portion 35b of the roof 35 in the fore-and-aft direction of the traveling body 7 and in the vicinity of the front end portion 35b of the roof 35 in the vertical direction. Therefore, the front distance sensor 101 is disposed in the vicinity of the front end portion 35b of the roof 35 and diagonally above the front end portion 35b of the roof 35, utilizing the space below the antenna unit 80. 11, at least a portion of the front distance sensor 101 overlaps with the front end portion 35b of the roof 35 from the line of sight of the occupant T seated in the driver's seat 39. The arrangement position of the front distance sensor 101 is such that at least a portion of the front distance sensor 101 is hidden by the front end portion 35b of the roof 35. The front distance sensor 101 is located in a position that is partially outside the visible range B1 in front of the occupant T seated in the driver's seat 39, which prevents the front distance sensor 101 from blocking the field of view of the occupant T seated in the driver's seat 39.

[0059] When the front distance sensor 101 is in the non-use position, as shown in Figures 8 and 9(b), the upper end of the front distance sensor 101 is positioned lower than the highest level line Z (see Figure 9(b)), similar to the antenna unit 80. This prevents not only the antenna unit 80 but also the front distance sensor 101 from protruding above the highest level line Z when transporting the tractor 1 or storing the tractor 1 in a storage location such as a barn.

[0060] The front distance sensor 101 is disposed at the center of the antenna unit 80 in the left-right direction of the traveling body 7. Since the antenna unit 80 is disposed at a position corresponding to the center of the cabin 10 in the left-right direction of the traveling body 7, the front distance sensor 101 is also disposed at a position corresponding to the center of the cabin 10 in the left-right direction of the traveling body 7.

[0061] As shown in FIGS. 6 and 7, in addition to the front distance sensor 101, a front camera 108, whose imaging range is the front side of the traveling body 7, is attached to the fifth mounting plate 205 by a connector or the like. The front camera 108 is arranged above the front distance sensor 101. Like the front distance sensor 101, the front camera 108 is attached in a forward-leaning position such that the more forward the position, the lower it is. The front camera 108 is equipped to capture images of the front side of the traveling body 7 while looking down diagonally from above. The image captured by the front camera 108 can be output to the outside. The image captured by the front camera 108 can be displayed on a display device such as the display unit of the tractor 1 or the display unit 51 of the mobile communication terminal 3, allowing a user or the like to visually confirm the situation around the tractor 1.

[0062] Next, the support structure of the rear distance sensor 102 will be described. 5 and 10, the rear distance sensor 102 is attached to a pipe-shaped sensor support stay 301 that extends over the entire length of the cabin 10 in the left-right direction of the traveling body 7. The rear distance sensor 102 is disposed at a position that corresponds to the center of the cabin 10 in the left-right direction of the traveling body 7.

[0063] As shown in Figures 5 and 10, the sensor support stay 301 is fixedly connected across the left and right rear support pillars 37 located at both left and right ends of the cabin 10. The sensor support stay 301 is formed in a bridge shape in a plan view, with both left and right end portions curved diagonally forward. Both left and right end portions of the sensor support stay 301 are fixedly connected via sixth mounting plates 206 to mounting members provided at the upper end portions of the left and right rear support pillars 37. The sixth mounting plate 206 is fixedly connected to both left and right end portions of the sensor support stay 301 by welding or the like. By fastening the sixth mounting plate 206 to the mounting members provided at the upper end portions of the rear support pillars 37 with connectors 50, the sensor support stay 301 is fixedly connected in a position extending horizontally.

[0064] As shown in Fig. 10 , the rear distance sensor 102 is attached to the sensor support stay 301 via a seventh attachment plate 207 and an eighth attachment plate 208. The seventh attachment plate 207 has a pair of left and right side wall surface portions 207a that face each other in the left-right direction, and is formed into a bridge shape with the upper ends of the side wall surface portions 207a connected to each other. The eighth attachment plate 208 has a pair of left and right attachment surface portions 208a that face each other in the left-right direction, and is formed into a bridge shape with the upper ends of the attachment surface portions 208a connected to each other. The lower edge of the side wall surface portions 207a of the seventh attachment plate 207 is fixedly connected to the sensor support stay 301 by welding or the like. A rear portion of the seventh attachment plate 207 and a front portion of the eighth attachment plate 208 are fixedly connected by a connector 50. A pair of left and right mounting surface portions 208a of the eighth mounting plate 208 are fixedly connected to both lateral sides of the rear distance sensor 102 by connectors 50. The rear distance sensor 102 is attached in a state where it is sandwiched between the left and right mounting surface portions 208a of the eighth mounting plate 208 in the left-right direction. A reinforcing plate 302 is fixedly connected to a front portion of the seventh mounting plate 207 by connectors or the like. The front portion of the reinforcing plate 302 is fixedly connected to the upper surface of the roof 35 by connectors 50. The reinforcing plate 302 is U-shaped with upright walls bent upward on both left and right side ends, extends in the front-rear direction, and is provided in a state spanning the roof 35, the seventh mounting plate 207, and the sensor support stay 301.

[0065] As shown in FIGS. 9(b) and 10, the rear distance sensor 102 is disposed at a position higher than the boarding / alighting step 41 (see FIG. 1) in the vertical direction, corresponding to the roof 35. The rear distance sensor 102 is attached to the sensor support stay 301 in a rearward-leaning position such that the rearward position is positioned lower. The rear distance sensor 102 is provided to measure the distance from a diagonally upward direction looking down at the rear side of the traveling vehicle body 7. The sensor support stay 301 is disposed near the rear end portion 35c of the roof 35 in the fore-and-aft direction of the traveling vehicle body 7 and at a position overlapping with the rear end portion 35c of the roof 35 in the vertical direction. Therefore, the rear distance sensor 102 is disposed at approximately the same height as the rear end portion 35c of the roof 35 or in a position diagonally upward and rearward from the rear end portion 35c. As a result, as shown in FIG. 11, at least a portion of the rear distance sensor 102 overlaps with the rear end portion 35c of the roof 35 from the line of sight of a passenger T seated in the driver's seat 39. The rear distance sensor 102 is positioned so that at least a portion of the rear distance sensor 102 is hidden by the rear end portion 35c of the roof 35. The rear distance sensor 102 is positioned so that a portion of the rear distance sensor 102 is outside the rearward visible range B2 of the occupant T seated in the driver's seat 39, and this prevents the field of view of the occupant T seated in the driver's seat 39 from being obstructed by the rear distance sensor 102.

[0066] As shown in Fig. 10, the rear distance sensor 102 is configured to be detachable from the rear support pillar 37 via a sensor support stay 301, a seventh mounting plate 207, and an eighth mounting plate 208. The rear distance sensor 102 can be installed later, and it is also possible to remove the rear distance sensor 102. The rear distance sensor 102 is supported by the rear support pillar 37 that constitutes the cabin frame 31 via the sensor support stay 301, and is therefore firmly supported while preventing the transmission of vibrations to the rear distance sensor 102, etc.

[0067] As shown in FIG. 10 , in addition to the rear distance sensor 102, a rear camera 109, whose imaging range is the rear side of the traveling machine body 7, is attached to the eighth mounting plate 208 by a connector or the like. The rear camera 109 is arranged above the rear distance sensor 102. Like the rear distance sensor 102, the rear camera 109 is attached in a rearward-leaning position such that the rearward portion is positioned lower. The rear camera 109 is equipped to capture images of the rear side of the traveling machine body 7 while looking down diagonally from above. The image captured by the rear camera 109 can be output to the outside. The image captured by the rear camera 109 can be displayed on a display device such as the display unit of the tractor 1 or the display unit 51 of the mobile communication terminal 3, allowing a user or the like to visually confirm the situation around the tractor 1.

[0068] The measurement range C of the front distance sensor 101 will be described. The front distance sensor 101 has a left-right measurement range C1 in the left-right direction as shown in Fig. 12, and also has a top-bottom measurement range C2 in the up-down direction as shown in Fig. 11. As a result, the front distance sensor 101 has set up-down, left-right, and front-back quadrangular pyramid-shaped measurement ranges C included in the left-right measurement range C1 and the top-bottom measurement range C2 within a range from itself to a position a first set distance X1 (see Fig. 12).

[0069] As shown in FIG. 12, the left-right measurement range C1 of the front distance sensor 101 is a symmetrical range in the left-right direction of the traveling body 7, with the left-right center line of the traveling body 7 as the axis of symmetry. The left-right measurement range C1 is set within the range of a first set angle α1 between a first boundary line E1 and a second boundary line E2 extending from the front distance sensor 101. As described above, the front distance sensor 101 has the left-right measurement range C1, but the entire left-right measurement range C1 is not used as an obstacle detection range; rather, the center of the left-right measurement range C1 is used as the obstacle detection range. Within the left-right measurement range C1, a detection range J for detecting obstacles is set at the center of the traveling body 7 in the left-right direction, and a non-detection range K for not detecting obstacles is set outside the detection range J. As a result, the range in which the front distance sensor 101 detects obstacles is the detection range J in the left-right direction. The detection range J is set in the left-right direction of the traveling body 7 to a range extending to a position a second set distance X2 on both the left and right sides of the center of the traveling body 7. The size of the detection range J can be changed as appropriate; for example, the size of the detection range J can be changed by arbitrarily changing the second set distance X2.

[0070] As shown in FIG. 11 , the vertical measurement range C2 of the front distance sensor 101 is set within a range of a second set angle α2 between a third boundary line E3 and a fourth boundary line E4 extending from the front distance sensor 101. The third boundary line E3 is set as a horizontal line extending horizontally forward from the front distance sensor 101, and the fourth boundary line E4 is set as a straight line located below a first tangent line G1 from the front distance sensor 101 to the upper front part of the front wheel 5. The vertical measurement range C2 is set so that a first center line F1 between the third boundary line E3 and the fourth boundary line E4 is located above the hood 8, ensuring a sufficiently large measurement range above the hood 8. By setting the fourth boundary line E4 below the first tangent line G1, even if an obstacle is present near the front end of the traveling body 7 (the front end of the hood 8), the obstacle can be detected.

[0071] As shown in Fig. 11, part of the hood 8 and part of the front wheel 5 are within the vertical measurement range C2 of the front distance sensor 101, so there is a possibility that the front distance sensor 101 may erroneously measure part of the hood 8 or part of the front wheel 5 as an obstacle. Therefore, a first masking process is performed to prevent such erroneous measurement. In the first masking process, the range within the measurement range C of the front distance sensor 101 where part of the hood 8 and part of the front wheel 5 exist is set in advance as a masking range L (see Fig. 13) where no obstacles are detected.

[0072] For example, in the first masking process, as a preprocessing step for using the front distance sensor 101, actual measurements are taken using the front distance sensor 101, and a 3D image generated from the measurement results is displayed on a display device such as the display unit of the tractor 1 or the display unit 51 of the mobile communication terminal 3. A user or the like operates the display device while checking the 3D image on the display device to set a masking range L in which no obstacles are detected. As shown in FIG. 13 , if a portion of the hood 8 and a portion of the front wheels 5 are present on the 3D image, the masking range L is set based on a reference range that includes a range La in which the portion of the hood 8 is present and a range Lb in which a portion of the front wheels 5 are present. Since the front wheels 5 are steered left and right by operating the steering wheel 38, power steering mechanism 14, etc., as shown by the dotted lines in FIG. 13 , it is preferable to set the masking range L so as to include the steering range in which the front wheels 5 are steered left and right.

[0073] 13, a mountain-shaped range that is larger than a reference range by a set range and that includes the range La where part of the hood 8 is located and the range Lb where part of the front wheels 5 are located is set as the masking range L. The masking range L can be set to a shape that corresponds to the shape of the hood 8 or the front wheels 5, for example, so as to include only the range La where part of the hood 8 is located and the range Lb where part of the front wheels 5 are located, and the range and shape of the masking range L can be changed as appropriate.

[0074] In this way, the front distance sensor 101 detects the presence or absence of an obstacle in the range included in the detection range J (see Figure 12) in the left-right direction and the up-down measurement range C2 (see Figure 11) in the up-down direction, excluding the masking range L.

[0075] The measurement range D of the rear distance sensor 102 will now be described. Similar to the front distance sensor 101, the rear distance sensor 102 has a left-right measurement range D1 in the left-right direction as shown in Fig. 12, and also has a top-bottom measurement range D2 in the up-down direction as shown in Fig. 11. As a result, the rear distance sensor 102 has set therein vertical, left-right, and front-rear quadrangular pyramid-shaped measurement ranges D included in the left-right measurement range D1 and the top-bottom measurement range D2 within a range from the rear distance sensor 102 to a position a third set distance X3 (see Fig. 12). Incidentally, X1 and X3 can be set to the same distance or different distances.

[0076] 12, the left-right measurement range D1 of the rear distance sensor 102 is set within the range of a third set angle α3 between a fifth boundary line E5 and a sixth boundary line E6 extending from the rear distance sensor 102, similar to the front distance sensor 101. In the left-right measurement range C1, a detection range J is set on the center side of the traveling body 7 in the left-right direction, and a non-detection range K is set outside the detection range J, so that the range in which the rear distance sensor 102 detects obstacles is the detection range J in the left-right direction.

[0077] As shown in FIG. 11 , the vertical measurement range D2 of the rear distance sensor 102 is set within a range of a fourth set angle α4 between a seventh boundary line E7 and an eighth boundary line E8 extending from the rear distance sensor 102. The working implement 12 is provided so that it can be raised and lowered between an elevated position and a lowered position. Therefore, in FIG. 11 , the working implement 12 positioned in the lowered position is shown by a solid line, and the working implement 12 positioned in the elevated position is shown by a dotted line. The seventh boundary line E7 is set as a horizontal line extending rearward from the rear distance sensor 102, and the eighth boundary line E8 is set as a straight line located below a second tangent line G2 extending from the rear distance sensor 102 toward the upper rear of the working implement 12 positioned in the lowered position. The vertical measurement range D2 is set so that a second center line F2 between the seventh boundary line E7 and the eighth boundary line E8 is located above the working implement 12 in the elevated position (shown by a dotted line in FIG. 11 ), ensuring a sufficiently large measurement range above the working implement 12 in the elevated position. By setting the eighth boundary line E8 below the second tangent line G2, it is possible to detect an obstacle even if it is present near the rear end of the working implement 12 in the lowered position.

[0078] Because part of the working implement 12 is within the vertical measurement range D2 of the rear distance sensor 102, there is a possibility that the rear distance sensor 102 may erroneously measure part of the working implement 12 as an obstacle. Therefore, a second masking process is performed to prevent such erroneous measurement. In the second masking process, the range within the measurement range D of the rear distance sensor 102 where part of the working implement 12 exists is set in advance as a masking range L (see FIGS. 14 and 15) where no obstacles are detected.

[0079] For example, in the second masking process, as in the first masking process, as a pre-processing before using the rear distance sensor 102, measurements are actually performed using the rear distance sensor 102, and a three-dimensional image generated from the measurement results at that time is displayed on a display device such as the display unit of the tractor 1 or the display unit 51 of the mobile communication terminal 3. A user or the like operates the display device while checking the three-dimensional image on the display device to set a masking range L in which no obstacles are detected.

[0080] As shown in FIG. 12, the working device 12 is raised and lowered between a lowered position and an upper position (positions indicated by dotted lines in the figure). Therefore, in the second masking process, a masking range L1 for the lowered position as shown in FIG. 14 and a masking range L2 for the upper position as shown in FIG. 15 are set as the masking range L. In FIGS. 14 and 15, the portion of the working device 12 that is within the measurement range D of the rear distance sensor 102 is indicated by a solid line, and the portion that is outside the measurement range D of the rear distance sensor 102 is indicated by a dotted line. The working device 12 is positioned at the lowered position by operating the lifting / lowering operating tool inside the cabin 10, and a masking range L1 for the lowered position is set using a three-dimensional image generated from the measurement results of the rear distance sensor 102 at that time. The working device 12 is positioned at the upper position by operating the lifting / lowering operating tool inside the cabin 10, and a masking range L2 for the upper position is set using a three-dimensional image generated from the measurement results of the rear distance sensor 102 at that time.

[0081] 14 and 15, rectangular masking ranges L1 and L2 are set as ranges that are larger than the reference range by a set range and include the range Lc where the operating device 12 is located. The masking range L can be set to a shape that corresponds to the shape of the operating device 12, for example, so as to include only the range Lc where the operating device 12 is located, and the ranges and shapes of the masking ranges L1 and L2 can be changed as appropriate.

[0082] In this way, the rear distance sensor 102 detects the presence or absence of an obstacle in a range that is included in the detection range J (see FIG. 12) in the left-right direction and in the up-down measurement range D2 (see FIG. 11) in the up-down direction, excluding the masking ranges L1 and L2. When the working implement 12 is in the lowered position, the rear distance sensor 102 detects an obstacle using the masking range L1 for the lowered position, and when the working implement 12 is in the upper position, it detects an obstacle using the masking range L2 for the upper position.

[0083] The sonars 103 to 106 will be described below. The sonars 103 to 106 are configured to measure the distance to the object from the time it takes for the projected ultrasonic waves to hit the object and bounce back. When an object exists within the measurement range as the object to be measured, the sonars 103 to 106 detect the object as an obstacle and measure the distance to the obstacle.

[0084] As shown in FIG. 12, the sonars 103 to 106 include two right-side sonars 103, 104 whose measurement range is on the right side of the tractor 1 (traveling body 7), and two left-side sonars 105, 106 whose measurement range is on the left side of the tractor 1 (traveling body 7), so that two sonars 103 to 106 are provided on each of the left and right sides of the tractor 1.

[0085] 16, a handrail 43 extending in the vertical direction is provided at the left front end of the cabin 10, and a boarding / alighting step 41 is provided on the left front lower side of the cabin 10. The left sonars 105, 106 are provided on the bottom surface of the boarding / alighting step 41, lined up in the fore-and-aft direction of the traveling vehicle body 7. Incidentally, although not shown, the right sonars 103, 104 are also provided on the bottom surface of the boarding / alighting step 41, which is provided on the lower right side of the cabin 10, lined up in the fore-and-aft direction of the traveling vehicle body 7, similar to the left sonars 105, 106.

[0086] 12, the measurement range N of the right sonars 103, 104 and the measurement range N of the left sonars 105, 106 differ only in that they extend in opposite directions from the traveling machine body 7, and the measurement ranges N on the right and left sides are symmetrical. Therefore, only the measurement range N of the left sonars 105, 106 will be explained, and an explanation of the measurement range N of the right sonars 103, 104 will be omitted.

[0087] The left sonars 105, 106 are intended to measure the area outside the traveling vehicle body 7. As shown in FIG. 16, the left sonars 105, 106 are attached to the traveling vehicle body 7 so as to project ultrasonic waves downward at a predetermined angle from the horizontal, and as shown in FIG. 12, a measurement range N is set so as to extend in a direction facing downward at a predetermined angle from the left sonars 105, 106. Each of the left sonars 105, 106 has an arc-shaped measurement range having a predetermined angle in a plan view. The measurement range N of the left sonars 105, 106 is set so that a portion of the measurement range of the left sonar 105 located on the front side overlaps a portion of the measurement range of the left sonar 106 located on the rear side in the front-to-rear direction. The measurement range N of the left sonar 105, 106 is a range with a radius of a predetermined distance from the left sonar 105, 106 to the left outside of the running body 7, and is set in the fore-and-aft direction of the running body 7 between the left range of the left-right measurement range C1 of the front distance sensor 101 and the left range of the left-right measurement range D1 of the rear distance sensor 102.

[0088] Obstacle control by the obstacle control unit 107 will be described below. First, obstacle control based on measurement information from the distance sensors 101 and 102 will be described, and then obstacle control based on measurement information from the sonars 103 to 106 will be described.

[0089] The tractor 1 is provided with two distance sensors, a front distance sensor 101 and a rear distance sensor 102, and the obstacle control unit 107 switches the obstacle detection state based on switching between forward and reverse at a forward / reverse switching point included in the target driving path P, or switching between forward and reverse using a reverse lever for forward / reverse switching provided inside the cabin 10. When the tractor 1 is traveling forward, the obstacle control unit 107 switches to a forward detection state in which the front distance sensor 101 detects obstacles, and when the tractor 1 is traveling backward, the obstacle control unit 107 switches to a backward detection state in which the rear distance sensor 102 detects obstacles. In this way, by switching which of the front distance sensor 101 and the rear distance sensor 102 is used to detect obstacles depending on whether the tractor 1 is traveling forward or backward, obstacle detection is performed while reducing the processing load.

[0090] In the forward movement detection state, the front distance sensor 101 detects the presence or absence of an obstacle in a range that is included in the detection range J (see FIG. 12) in the left-right direction and in the up-down measurement range C2 (see FIG. 11) in the up-down direction, excluding the masking range L (see FIG. 13). In the backward movement detection state, when the working implement 12 is in the lowered position, the rear distance sensor 102 detects the presence or absence of an obstacle in a range that is included in the detection range J (see FIG. 12) in the left-right direction and in the up-down measurement range D2 (see FIG. 11) in the up-down direction, excluding the masking range L1 for the lowered position (see FIG. 14). In the backward movement detection state, when the working implement 12 is in the upper position, the rear distance sensor 102 detects the presence or absence of an obstacle in a range that is included in the detection range J (see FIG. 12) in the left-right direction and in the up-down measurement range D2 (see FIG. 11) in the up-down direction, excluding the masking range L2 for the upper position (see FIG. 15).

[0091] When an obstacle is detected by the front distance sensor 101 or the rear distance sensor 102, the obstacle control by the obstacle control unit 107 is set to vary depending on the range of detection range J in which the obstacle is detected, as shown in FIG. 12 . The detection range J is set into three ranges, a first detection range J1, a second detection range J2, and a third detection range J3, depending on the distance from the front distance sensor 101 or the rear distance sensor 102. The first detection range J1 is set to a range from the front LIDAR sensor 101 or the rear LIDAR sensor 102 between a fourth set distance X4 and the first set distance X1 or between the fourth set distance X4 and the third set distance X3. The second detection range J2 is set to a range from the front distance sensor 101 or the rear distance sensor 102 between a fifth set distance X5 and the fourth set distance X4. The third detection range J3 is set to a range from the front distance sensor 101 or the rear distance sensor 102 up to the fifth set distance X5. Therefore, the first detection range J1, the second detection range J2, and the third detection range J3 are set to be closer in that order to the tractor 1 including the front distance sensor 101, the rear distance sensor 102, and the implement 12.

[0092] The control content of obstacle control based on the measurement information of the distance sensors 101, 102 is the same whether the tractor 1 is traveling forward or backward, so the following will explain the case where the tractor 1 is traveling forward.

[0093] 12, when the front distance sensor 101 detects an obstacle within the first detection range J1 while the tractor 1 is traveling forward, the obstacle control unit 107 performs first notification control to control the notification device 26, such as a notification buzzer or a notification lamp, to notify the driver that an obstacle is present within the first detection range J1. In the first notification control, for example, the obstacle control unit 107 controls the notification device 26 to operate the notification buzzer intermittently at a predetermined frequency and to light up the notification lamp in a predetermined color.

[0094] When the front distance sensor 101 detects an obstacle within the second detection range J2, the obstacle control unit 107 controls the alarm device 26, such as an alarm buzzer or an alarm lamp, to perform second alarm control, which notifies the driver that an obstacle is present within the second detection range J2, and also performs first deceleration control, which decelerates the vehicle speed of the tractor 1. In the second alarm control, for example, the obstacle control unit 107 controls the alarm device 26 to intermittently operate the alarm buzzer at a predetermined frequency and to light the alarm lamp in a predetermined color. In the first deceleration control, for example, the obstacle control unit 107 calculates a predicted collision time until the tractor 1 collides with the obstacle based on the current vehicle speed of the tractor 1, the distance to the obstacle, and the like. The obstacle control unit 107 controls the engine 9, the transmission 13, the brake operation mechanism 15, and the like to decelerate the vehicle speed of the tractor 1 while maintaining the calculated predicted collision time at a set time (for example, 3 seconds).

[0095] When the front distance sensor 101 detects an obstacle within the third detection range J3, the obstacle control unit 107 controls the alarm device 26, such as an alarm buzzer or an alarm lamp, to perform third alarm control for notifying the driver that an obstacle is present within the third detection range J3, and also performs stop control for stopping the tractor 1. In the third alarm control, for example, the obstacle control unit 107 controls the alarm device 26 to continuously operate the alarm buzzer and to light up the alarm lamp in a predetermined color. In the stop control, for example, the obstacle control unit 107 controls the brake operation mechanism 15 and the like to stop the tractor 1.

[0096] Incidentally, the predetermined frequency for turning on and off the notification buzzer in the first notification control and the second notification control may be the same frequency or different frequencies. Also, the predetermined color for lighting the notification lamp in the first to third notification controls may be the same color or different colors. In the first to third notification controls, the obstacle control unit 107, in addition to controlling the notification device 26 of the tractor 1, can also control the terminal electronic control unit 52 to display on the display unit 51 of the mobile communication terminal 3 display content indicating the presence of an obstacle in any of the first to third detection ranges J1 to J3.

[0097] For example, if an obstacle is detected within the first detection range J1, the obstacle control unit 107 performs first notification control to notify the user or the like that an obstacle exists within the first detection range J1. If the tractor 1 continues traveling and the obstacle detection range approaches the second detection range J2 from the first detection range J1, the obstacle control unit 107 performs first deceleration control in addition to the second notification control to decelerate the vehicle speed of the tractor 1 to avoid a collision between the tractor 1 and the obstacle. Even if the tractor 1 is decelerated, if the obstacle detection range approaches the third detection range J3 from the second detection range J2, the obstacle control unit 107 performs stop control in addition to the third notification control to stop the tractor 1, thereby appropriately avoiding a collision between the tractor 1 and the obstacle.

[0098] The distance sensors 101 and 102 also detect moving measurement objects, such as people, as obstacles. Therefore, even if an obstacle is detected within the detection range J, the obstacle itself may move and move out of the detection range J. Therefore, when the obstacle moves out of the first detection range J1, the obstacle control unit 107 terminates the first notification control. When the obstacle moves out of the second detection range J2, the obstacle control unit 107 terminates the second notification control and performs vehicle speed recovery control to control the engine 9, the transmission 13, etc. so as to increase the vehicle speed of the tractor 1 to a set vehicle speed. When the obstacle moves out of the third detection range J3, the obstacle control unit 107 terminates the third notification control while maintaining the tractor 1 in a stopped state. In this case, the tractor 1 can resume automatic traveling by receiving a command from a user or the like to resume automatic traveling of the tractor 1.

[0099] Next, obstacle control based on measurement information from the sonars 103 to 106 will be described. There are four sonars 103 to 106, two on each side, and all four sonars 103 to 106 are used to detect obstacles whether the tractor 1 is traveling forward or backward.

[0100] When an obstacle is detected by any of the sonars 103 to 106, the obstacle control unit 107 controls the alarm device 26, such as an alarm buzzer or an alarm lamp, to perform a fourth alarm control for notifying the user that an obstacle is present within the measurement range N of any of the sonars 103 to 106, and also performs a second deceleration control for decelerating the speed of the tractor 1. In the fourth alarm control, for example, the obstacle control unit 107 controls the alarm device 26 to intermittently operate the alarm buzzer at a predetermined frequency and to light up the alarm lamp in a predetermined color. In the second deceleration control, for example, the obstacle control unit 107 controls the engine 9, the transmission 13, the brake operation mechanism 15, etc., to decelerate the speed of the tractor 1 to a set speed.

[0101] In this way, the obstacle detection system 100 can detect the presence or absence of obstacles in front of and behind the traveling body 7 using the front distance sensor 101 and the rear distance sensor 102, and can also detect the presence or absence of obstacles on the left and right of the traveling body 7 using the sonars 103 to 106. When the obstacle detection system 100 detects the presence of an obstacle, the obstacle control unit 107 notifies the user or the like of the presence of the obstacle, and can urge the user or the like to avoid collision with the obstacle, and even if there is a possibility of a collision between the tractor 1 and the obstacle, the tractor 1 can be slowed down or stopped to appropriately avoid a collision between the tractor 1 and the obstacle.

[0102] In the automatic driving state, automatic driving control is performed by the on-board electronic control unit 18, so the obstacle detection system 100 can slow down or stop the tractor 1, allowing the tractor 1 to automatically drive while avoiding collision with an obstacle. Even in the manual driving state, the obstacle detection system 100 can notify the user, etc., who is driving, of the presence of an obstacle and support driving to avoid collision between the tractor 1 and the obstacle.

[0103] [Another embodiment] Another embodiment of the present invention will now be described. The configurations of the embodiments described below are not limited to being applied independently, but can also be applied in combination with the configurations of other embodiments.

[0104] (1) The configuration of the work vehicle can be changed in various ways. For example, the work vehicle may be configured as a hybrid vehicle equipped with an engine 9 and an electric motor for running, or may be configured as an electric vehicle equipped with an electric motor for running instead of the engine 9. For example, the work vehicle may be configured as a semi-crawler vehicle having left and right crawlers instead of the left and right rear wheels 6 as a traveling part. For example, the work vehicle may be configured with rear-wheel steering specifications in which the left and right rear wheels 6 function as steering wheels.

[0105] (2) In the above embodiment, the front distance sensor 101 and the rear distance sensor 102 are positioned at a position corresponding to the roof 35 in the vertical direction, but for example, the front distance sensor 101 can be positioned at the front end of the hood 8. The positions of the front distance sensor 101 and the rear distance sensor 102 need only be above the boarding and alighting step 41, which serves as the boarding and alighting area, and the positions can be changed as appropriate.

[0106] The front distance sensor 101 and the rear distance sensor 102 may be arranged at different heights in the vertical direction. For example, the front distance sensor 101 may be arranged at the front end of the hood 8, and the rear distance sensor 102 may be arranged at a position corresponding to the roof 35.

[0107] (3) In the above embodiment, the front distance sensor 101 is attached to the bottom of the antenna unit 80. However, for example, the front distance sensor 101 can also be attached to the roof 35 via a support stay, and the type of member to which the front distance sensor 101 is attached can be changed as appropriate.

[0108] (4) In the above embodiment, an example was shown in which two distance sensors, the front distance sensor 101 and the rear distance sensor 102, were provided, but the number of distance sensors can be changed as appropriate, and can be one or three or more.

[0109] (5) In the above embodiment, when any object to be measured exists within the measurement range, the distance sensors 101, 102 detect the object as an obstacle and measure the direction in which the obstacle exists and the distance to the obstacle. However, for example, the distance sensors 101, 102 may only measure the distance to the object to be measured existing within the measurement range in three dimensions, and the obstacle control unit 107 may perform obstacle detection processing to detect the object to be measured within a predetermined distance as an obstacle based on the measurement information of the distance sensors 101, 102. In other words, the function of detecting an obstacle may be provided on the obstacle sensors 101, 102 side, or may be provided on the tractor 1 side, such as the obstacle control unit 107 of the on-board electronic control unit 18.

[0110] Also, the sonars 103 to 106 may only measure the distance to a measurement object that exists within the measurement range, and the obstacle control unit 107 may perform obstacle detection processing to detect a measurement object within a predetermined distance as an obstacle based on the measurement information of the sonars 103 to 106. As for the sonars 103 to 106, the function of detecting an obstacle may be provided on the sonars 103 to 106 side, or it may be provided on the tractor 1 side, such as in the obstacle control unit 107 of the on-board electronic control unit 18.

[0111] <Notes on the invention> The first characteristic configuration of the present invention is that it comprises a traveling vehicle body having a traveling section, a driver's seat arranged on the traveling vehicle body, and a distance sensor capable of measuring the distance to an object to be measured in three dimensions, and the distance sensor is arranged above the access point to the driver's seat.

[0112] According to this configuration, the distance sensor can measure the distance to the object in three dimensions, so it can accurately measure the distance to the object without being installed closer to the object. This allows the distance sensor to be positioned above the boarding / exiting area while still being able to accurately measure the distance to the object, and prevents mud, water, and the like from splashing onto the distance sensor. This allows the distance sensor to accurately measure the distance to the object while preventing a decrease in measurement accuracy or an inability to perform measurement at all.

[0113] A second characteristic feature of the present invention is that a roof covering the upper part of the driver's seat is provided, and the distance sensor is disposed at a position corresponding to the roof in the up-down direction.

[0114] According to this configuration, the distance sensor is disposed at a position equivalent to the roof, so even if mud, water, etc. are scattered, the mud, water, etc. will not reach the distance sensor, and the distance sensor can be reliably prevented from adhering to the mud, water, etc. Furthermore, by disposing the distance sensor at a position equivalent to the roof, it is possible to measure the distance to the measurement object over a wide range below the roof, for example, and the distance sensor can be used effectively.

[0115] A third characteristic feature of the present invention is that the distance sensor is disposed at a position where at least a part of the distance sensor is out of the visible range of a passenger seated in the driver's seat.

[0116] Depending on the installation position of the distance sensor, the entire distance sensor may be within the visible range of the passenger, significantly blocking the passenger's field of vision. Therefore, with this configuration, the distance sensor is disposed at a position where at least a portion is outside the visible range of the passenger, thereby reducing or eliminating the range of the passenger's field of vision blocked by the distance sensor.

[0117] A fourth characteristic configuration of the present invention is that the distance sensor is positioned so that its measurement range includes an area including the front side of the running body, and the measurement range of the distance sensor is set to a range that includes a portion of the running part on the front side of the running body.

[0118] According to this configuration, the measurement range of the distance sensor is set to a range that includes part of the traveling section, so while the distance sensor is positioned above the boarding / disembarking section, it is possible to measure the distance to the object over a large measurement range that also includes the ground surface on which the traveling section travels. Therefore, for example, when the distance sensor is used to detect an obstacle, a large measurement range that includes the ground surface can be ensured, so that obstacles present near the front end of the traveling body can also be detected, allowing for appropriate obstacle detection.

[0119] A fifth characteristic configuration of the present invention is that a working device is provided at the rear of the running body so as to be able to rise and fall freely between an elevated position and a lowered position, the distance sensor is positioned so that its measurement range includes an area including the rear side of the running body, and the measurement range of the distance sensor is set so that its center line in the vertical direction is located above the working device in the elevated position.

[0120] With this configuration, the center line of the measurement range of the distance sensor in the vertical direction is located above the working device in the raised position, so a large measurement range can be secured above the working position in the raised position. For example, when the distance sensor is used to detect obstacles, the working device can be raised and lowered between the raised and lowered positions to perform appropriate work, and even when the working device is in the raised position, a large measurement range can be secured and obstacles can be properly detected.

[0121] A work vehicle according to a first aspect of the present invention includes a traveling body having a traveling section, a driver's seat arranged on the traveling body, a sensor capable of detecting an object ahead of the traveling body, and a roof covering the upper part of the driver's seat. The sensor is arranged above the access point to the driver's seat and below the highest line passing through the highest part of the roof.

[0122] A work vehicle according to a second aspect of the present invention includes a traveling body having a traveling section, a driver's seat arranged on the traveling body, a sensor capable of detecting objects behind the traveling body, and a roof covering the upper part of the driver's seat. The sensor is arranged above the access point to the driver's seat and below the highest line passing through the highest part of the roof. [Explanation of symbols]

[0123] 1 Tractor (work vehicle) 5 Front wheels (running part) 6 Rear wheels (running part) 7 Running body 12 Work equipment 35 Roof 39 Driver's seat 41 Boarding and alighting steps (boarding and alighting area) 101 Front distance sensor 102 Rear distance sensor B1 Forward visibility range B2 Rear visibility range C Measurement range of front distance sensor D Rear distance sensor measurement range F2 Second center line of rear distance sensor (center line) T Passenger

Claims

1. A traveling machine body having a traveling section, a working device connected to the rear of the traveling machine body, a distance sensor capable of detecting an object on the rear side of the traveling machine body, and a camera capable of capturing an image of the rear side of the traveling machine body. Work vehicle.

2. The distance sensor and the camera are arranged on the rear side of the traveling machine body, The work vehicle according to claim 1 .

3. The distance sensor and the camera are arranged side by side in the vertical direction. The work vehicle according to claim 1 or 2.

4. The distance sensor is capable of detecting an object on the rear side of the working device, The camera is capable of capturing an image of the rear side of the working device. A work vehicle according to any one of claims 1 to 3.

5. The distance sensor and the camera are arranged outside the roof provided on the traveling machine body in a plan view, A work vehicle according to any one of claims 1 to 4.

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