JP7458143B2 - Obstacle detection system - Google Patents

Description

The present invention relates to an obstacle detection system mounted on a work vehicle.

A distance measurement unit that measures the distance to surrounding distance measurement points, and an obstacle detection unit that detects obstacles such as people or other vehicles within a predetermined obstacle detection area based on the measurement results of the distance measurement unit. Obstacle detection systems are known that include a section and a section. Such an obstacle detection system is installed in a work vehicle equipped with a collision avoidance control section that controls the traveling of the work vehicle so as to avoid a collision with an obstacle detected by the obstacle detection section (for example, as disclosed in the patent (See Reference 1). The distance measuring unit included in such an obstacle detection system calculates the distance to the distance measuring point based on the time it takes to emit a laser beam (an example of measurement light) to the surrounding area and return to the distance measuring point. It is configured to measure distance, etc.

JP 2018-014554 A

In a work vehicle that travels and performs work in a field or the like, floating objects such as dust and dust are likely to be generated in the air around the vehicle, and the distance measuring section is likely to become dirty. For this reason, in the obstacle detection system installed on the work vehicle, the measurement light emitted by the distance measuring section is reflected by floating objects and dirt, so that the floating objects and dirt are detected by the obstacle detection section. There is a problem in that the object is incorrectly detected as an obstacle, and as a result, the work vehicle is stopped needlessly by collision avoidance control.
In view of this situation, the main problem of the present invention is to suppress the false detection of obstacles in an obstacle detection system mounted on a work vehicle, while preventing unnecessary stoppage of the work vehicle due to the false detection of the obstacle. The goal is to provide technology that can avoid this.

A first characteristic configuration of the obstacle detection system according to the present invention is that the obstacle detection system is mounted on a work vehicle, and
a distance measuring unit that irradiates the surrounding area with measurement light and receives reflected light of the measurement light to measure the distance to the distance measurement point from which the measurement light is reflected;
An obstacle detection system comprising: an obstacle detection unit that detects an obstacle within a predetermined obstacle detection area based on the measurement result of the distance measurement unit,
The obstacle detection section performs the measurement using at least one of the intensity of reflected light from the distance measurement point received by the distance measurement section and the distance to the distance measurement point measured by the distance measurement section. The point is to determine whether the distance point is a non-obstacle.

According to this configuration, in addition to the criterion for determining whether or not a distance measurement point is within an obstacle detection area, at least one of the intensity of reflected light from the distance measurement point and the distance to the distance measurement point is used to determine whether the distance measurement point is within the obstacle detection area. The obstacle detection unit determines whether the distance measurement point is a non-obstruction. This means that if the distance measurement point where the measurement light is reflected is covered with floating objects such as dust or dirt that do not impede the movement of the work vehicle, it is determined that the object is not an obstacle but a non-obstacle. By determining that this is the case, it is possible to avoid, for example, unnecessary stopping of the work vehicle.
Therefore, according to the present invention, in an obstacle detection system mounted on a work vehicle, it is possible to suppress false detection of an obstacle and avoid unnecessary stoppage of the work vehicle due to false detection of the obstacle. technology can be provided.

The second characteristic configuration of the obstacle detection system according to the present invention is, in addition to the first characteristic configuration, that the obstacle detection unit executes a floating object determination process to determine that the distance measurement point where the distance measured by the distance measurement unit is within a range from a predetermined first set distance to a predetermined second set distance that is greater than the first set distance and the intensity of the reflected light received by the distance measurement unit is less than a predetermined set intensity is a floating object that is a non-obstacle.

According to this configuration, the reflected light reflected from the distance measuring points among the distance measuring points whose distance measured by the distance measuring unit is within the range from the first set distance to the second set distance larger than the first set distance. If the intensity of the object is less than a relatively small set intensity, the obstacle detection unit can determine that it is a floating object floating in the air around the work vehicle by executing floating object determination processing. .
Therefore, when the work vehicle travels around a field or the like where floating objects are likely to occur and performs work, it is possible to prevent the floating objects from being erroneously detected as obstacles.

A third characteristic configuration of the obstacle detection system according to the present invention is that, in addition to any one of the first characteristic configuration to the second characteristic configuration, the obstacle detection section has a distance measured by the distance measuring section. The object of the present invention is to execute a dirt determination process in which the distance measuring point whose distance is less than a predetermined first set distance is determined to be dirt on the distance measuring section as the non-obstacle.

According to this configuration, when the distance measured by the distance measuring section is very close and is less than the first set distance, the obstacle detection section executes the dirt determination process, so that the distance measuring section is dirty. It can be determined that
Therefore, when the working vehicle travels and performs work in a field or the like where the distance measuring section is likely to get dirty, it is possible to prevent the dirt from being erroneously detected as an obstacle.

The fourth characteristic configuration of the obstacle detection system according to the present invention is that, in addition to the third characteristic configuration, the obstacle detection unit determines the proportion of the distance measurement points determined to be dirty on the distance measurement unit as a dirt ratio, and outputs a predetermined dirt alarm if the dirt ratio is equal to or greater than a predetermined set dirt ratio.

According to this configuration, by outputting a dirt alarm, it is possible to make the user aware that the ranging section is dirty and motivate the user to remove the dirt. Therefore, it is possible to avoid a decrease in accuracy or damage to the distance measuring section due to such problems.

A diagram showing the schematic configuration of an automated driving system Block diagram showing the schematic configuration of an automated driving system Diagram showing the target driving route Diagram showing the upper part of the tractor when viewed from the front Diagram showing the upper part of the tractor in rear view Diagram showing the antenna unit and front lidar sensor in the use position when viewed from the side A perspective view showing the support structure of the antenna unit and front lidar sensor. Diagram showing the antenna unit and front lidar sensor in a non-use position when viewed from the side Diagrams showing the roof, antenna unit, front lidar sensor, and rear lidar sensor in side view in use position and non-use position Perspective view showing the support structure of the rear lidar sensor Diagram showing obstacle detection areas of front lidar sensor and rear lidar sensor in side view A diagram showing the obstacle detection areas of the front lidar sensor, rear lidar sensor, and sonar in plan view. Diagram showing a distance image generated from the measurement information of the front lidar sensor Diagram showing a distance image generated from the measurement information of the rear lidar sensor with the work equipment in the lowered position Diagram showing a distance image generated from the measurement information of the rear lidar sensor with the work equipment in the raised position Flowchart showing the flow of obstacle detection processing Flowchart showing the flow of movement determination processing Diagram explaining the determination range of obstacles and non-obstacles based on straight line distance and intensity of reflected light Diagram showing an example of dirt alarm display Diagram illustrating an example method for determining individual distance measurement points Diagram explaining how to create a grid map Diagram explaining the method of determining identical obstacles and their centroid positions Diagram showing an example of multiple grid maps created in succession up to this point Diagram showing an example of multiple grid maps created in succession up to this point A diagram showing examples of multiple grid maps created in succession to date.

An embodiment in which a work vehicle equipped with an obstacle detection system according to the present invention is applied to an automatic driving system will be described based on the drawings.
In this automatic driving system, as shown in FIG. 1, a tractor 1 is used as a work vehicle according to the present invention, but other vehicles other than the tractor include a riding rice transplanter, a combine harvester, a riding mower, a wheel loader, a snowplow, etc. The invention can be applied to unmanned work vehicles such as passenger work vehicles and unmanned lawn mowers.

As shown in FIGS. 1 and 2, this automatic travel system includes an automatic travel unit 2 mounted on a tractor 1, and a mobile communication terminal 3 configured to communicate with the automatic travel unit 2. As the mobile communication terminal 3, a tablet-type personal computer, a smartphone, or the like having a touch-operable display section 51 (for example, a liquid crystal panel) can be adopted.

The tractor 1 includes a traveling body 7 having left and right front wheels 5 that function as drivable steered wheels, and left and right rear wheels 6 that can be driven. A bonnet 8 is disposed on the front side of the traveling body 7, and within the bonnet 8 is provided an electronically controlled diesel engine (hereinafter referred to as an engine) 9 equipped with a common rail system. A cabin 10 forming a boarding type driving section is provided on the rear side of the bonnet 8 of the traveling body 7.

The tractor 1 can be configured for rotary tillage by connecting a rotary tillage device, which is an example of a working device 12, to the rear of the running body 7 via a three-point link mechanism 11 so that it can be raised, lowered, and rolled. Instead of a rotary tillage device, a working device 12 such as a plow, harrow, vertical harrow, stubble cultivator, seeding device, or spraying device can be connected to the rear of the tractor 1.

As shown in FIG. 2, the tractor 1 includes 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, and left and right rear wheels 6. Left and right hand brakes (not shown) for braking, an electronically controlled brake operation mechanism 15 that enables hydraulic operation of the left and right hand brakes, and a work clutch (not shown) that connects and disconnects transmission to a work device 12 such as a rotary tiller (not shown), an electronically controlled clutch operating mechanism 16 that enables hydraulic operation of the work clutch, an electrohydraulically controlled lifting drive mechanism 17 that drives the working device 12 such as a rotary tiller up and down, automatic driving of the tractor 1, etc. an on-vehicle electronic control unit 18 having various control programs, etc., 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 measures the current position and current direction of the tractor 1. A positioning unit 21 and the like is provided.

Note that 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), a belt continuously variable transmission, or the like. The power steering mechanism 14 may be an electric power steering mechanism 14 including an electric motor.

As shown in FIGS. 4 and 5, the cabin 10 includes a cabin frame 31 that forms the frame of the cabin 10, a windshield 32 that covers the front side, a rear glass 33 that covers the rear side, and an axis that extends in the vertical direction. It has a box-like structure including a pair of left and right doors 34 (see FIG. 1) that can be swung open and closed, and a roof 35 on the ceiling side. The cabin frame 31 includes a pair of left and right front struts 36 disposed at the front end, and a pair of left and right rear struts 37 disposed at the rear end. In plan view, front columns 36 are arranged at both left and right corners on the front side, and rear columns 37 are arranged at both left and right corners on the rear side. The cabin frame 31 is supported on the traveling body 7 via a vibration isolating member such as an elastic body, and is provided with anti-vibration measures to prevent vibrations from the traveling body 7 etc. from being transmitted to the cabin 10. In this state, a cabin 10 is provided.

Inside the cabin 10, as shown in FIG. 1, there are a steering wheel 38 that enables manual steering of the left and right front wheels 5 via the power steering mechanism 14 (see FIG. 2), a driver's seat 39 for the passenger, and a touch panel. It is equipped with a formula display section and various operating tools. On both lateral sides of the front side portion of the cabin 10, boarding steps 41 are provided that serve as a boarding/disembarking section for the cabin 10 (driver's seat 39).

As shown in FIG. 2, the in-vehicle electronic control unit 18 includes a shift control section 181 that controls the operation of the transmission 13, a brake control section 182 that controls the operation of the left and right hand brakes, and a control section 182 that controls the operation of the working device 12 such as a rotary tiller. a working device control section 183 that controls the operation; a steering angle setting section 184 that sets a target steering angle for the left and right front wheels 5 during automatic driving and outputs it to the power steering mechanism 14;
The vehicle also includes a non-volatile in-vehicle storage unit 185 that stores a preset target travel route P for automatic travel (for example, see FIG. 3).

As shown in FIG. 2, the positioning unit 21 includes a satellite that measures the current position and current direction of the tractor 1 using a GPS (Global Positioning System), which is an example of a navigation satellite system (NSS). A navigation device 22 and an inertial measurement unit (IMU) 23 having a 3-axis gyroscope, a 3-direction acceleration sensor, etc. and measuring the attitude, direction, etc. of the tractor 1 are provided. Positioning methods using GPS include DGPS (Differential GPS) and RTK-GPS (Real Time Kinematic GPS). In this embodiment, RTK-GPS, which is suitable for positioning a mobile object, is employed. Therefore, as shown in FIGS. 1 and 2, a reference station 4 is installed at a known position around the field to enable positioning by RTK-GPS.

As shown in FIG. 2, each of the tractor 1 and the reference station 4 is equipped with a GPS satellite 71 (see FIG. 1).
GPS antennas 24 and 61 that receive radio waves transmitted from the tractor 1 and communication modules 25 and 62 that enable wireless communication of various information including positioning data between the tractor 1 and the reference station 4 are provided. As a result, the satellite navigation device 22 receives the positioning data obtained by the GPS antenna 24 on the tractor side receiving radio waves from the GPS satellite 71 and the GPS antenna 61 on the base station side receiving the radio waves from the GPS satellite 71. Based on the obtained positioning data, the current position and current direction of the tractor 1 can be measured with high accuracy. Furthermore, the positioning unit 21 is equipped with a satellite navigation device 22 and an inertial measurement device 23, so that it can measure the current position, current azimuth, and attitude angle (yaw angle, roll angle, pitch angle) of the tractor 1 with high precision. Can be done.

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

As shown in FIG. 2, the mobile communication terminal 3 includes a terminal electronic control unit 52 having various control programs for controlling the operation of the display section 51, etc., and positioning data transmitted between the terminal electronic control unit 52 and the communication module 25 on the tractor side. A communication module 55 that enables wireless communication of various information including information is provided. The terminal electronic control unit 52 includes a travel route generation section 53 that generates a target travel route P (for example, see FIG. 3) for travel guidance for automatically driving the tractor 1, and various input data input by the user. It has a nonvolatile terminal storage unit 54 that stores the target driving route P generated by the driving route generating unit 53, and the like.

When the driving route generation unit 53 generates the target driving route P, a user such as a driver or an administrator can operate a work vehicle or Vehicle body data such as the type and model of the working device 12 is input, and the input vehicle body data is stored in the terminal storage section 54. The driving area S (see FIG. 3) for which the target driving route P is generated is a farm field, and the terminal electronic control unit 52 of the mobile communication terminal 3 acquires field data including the shape and position of the field and stores it in the terminal storage unit. I remember it in 54.

To explain the acquisition of field data, when a user or the like actually drives the tractor 1, the terminal electronic control unit 52 determines the shape and position of the field based on the current position of the tractor 1 acquired by the positioning unit 21. It is possible to obtain location information for identifying etc. The terminal electronic control unit 52 specifies the shape and position of the field from the acquired position information, and acquires field data including the specified driving area S from the specified shape and position of the field.
FIG. 3 shows an example in which a rectangular driving area S is specified.

When the field data including the shape and position of the specified field is stored in the terminal storage unit 54, the driving route generation unit 53 uses the field data and vehicle body data stored in the terminal storage unit 54 to determine the target. A driving route P is generated.

As shown in FIG. 3, the driving route generation unit 53 divides the driving area S into a central area R1 and an outer peripheral area R2. The central region R1 is set at the center of the driving region S, and is a reciprocating work region in which the tractor 1 automatically travels in a reciprocating direction in advance to perform a predetermined work (for example, work such as plowing). . The outer peripheral region R2 is set around the central region R1,
Following the central area R1, this is a circular work area where the tractor 1 automatically travels in a circular direction to perform a predetermined work. The driving route generation unit 53 calculates, for example, the space for turning required for the tractor 1 to turn around the edge of the field, based on the turning radius, longitudinal width, lateral width, etc. of the tractor 1 included in the vehicle body data. I'm looking for. The traveling route generation unit 53 divides the inside of the traveling region S into a central region R1 and an outer peripheral region R2 so as to secure the required space on the outer periphery of the central region R1.

As shown in FIG. 3, the driving route generation unit 53 generates a target driving route P using vehicle body data, field data, and the like. For example, the target travel route P includes a plurality of work routes P1 that have the same straight distance in the central region R1 and are arranged in parallel at a certain distance corresponding to the work width, and the starting end of the adjacent work route P1. It has a connecting path P2 that connects the terminal end, and a circular path P3 (indicated by a dotted line in the figure) that goes around the outer circumferential region R2. The plurality of work routes P1 are routes for performing predetermined work while causing the tractor 1 to travel straight. The connecting route P2 is a U-turn route for changing the traveling direction of the tractor 1 by 180 degrees without performing a predetermined work, and connects the end of the working route P1 to the starting end of the next adjacent working route P1. ing. The circular route P3 is a route for performing a predetermined work while causing the tractor 1 to travel circularly in the outer peripheral region R2. On the circuit route P3, the running direction of the tractor 1 is changed by 90 degrees by switching the tractor 1 between forward running and backward running at positions corresponding to the four corners of the running area S. Incidentally, the target travel route P shown in FIG. 3 is just an example, and what kind of target travel route is set can be changed as appropriate.

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 of the target travel route P, as well as a set engine rotation speed and a target travel speed that are set according to the travel mode of the tractor 1 on the target travel route P, and the like.

In this way, when the driving route generation unit 53 generates the target driving route P, the terminal electronic control unit 52 transfers the route data from the mobile communication terminal 3 to the tractor 1, so that the on-board electronic control unit 18 of the tractor 1 can 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 driving route P while acquiring its own current position (the current position of the tractor 1) with 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.

Regarding the transfer of route data, the entire route data can be transferred at once from the terminal electronic control unit 52 to the on-vehicle electronic control unit 18 at a stage before the tractor 1 starts automatic travel. Furthermore, for example, the route data including the target travel route P can be divided into a plurality of route parts each having a predetermined distance with a small amount of data. In this case, before the tractor 1 starts automatic travel, only the initial route portion of the route data is transferred from the terminal electronic control unit 52 to the on-vehicle electronic control unit 18. After the start of automatic driving, each time the tractor 1 reaches a route acquisition point set according to the amount of data, etc., the route data for only the subsequent route portion corresponding to that point is transmitted from the terminal electronic control unit 52 to the on-vehicle electronic control. The information may be transferred to the unit 18.

When starting automatic travel of the tractor 1, for example, when the user or the like moves the tractor 1 to the starting point and various automatic travel start conditions are met, the user selects the display unit 51 on the mobile communication terminal 3. By operating , the mobile communication terminal 3 transmits an instruction to start automatic driving to the tractor 1 . As a result, in the tractor 1, the in-vehicle electronic control unit 18 receives the instruction to start automatic driving, and while the positioning unit 21 acquires its own current position (the current position of the tractor 1), the vehicle-mounted electronic control unit 18 moves to the target driving route P. Automatic travel control for automatically driving the tractor 1 along the route is started. The on-vehicle electronic control unit 18 performs automatic travel control to automatically travel the tractor 1 along the target travel route P based on the positioning data of the tractor 1 acquired by the positioning unit 21 (corresponding to a satellite positioning system). It is configured as a travel control section.

The automatic driving control includes automatic shift control that automatically controls the operation of the transmission 13, automatic braking control that automatically controls the operation of the brake operation mechanism 15, automatic steering control that automatically steers the left and right front wheels 5,
Also included is an automatic work control that automatically controls the operation of the work device 12 such as a rotary tiller.

In automatic gear shift control, the gear shift control unit 181 automatically controls the operation of the gear shift device 13 based on the 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 according to the driving mode of the tractor 1 on the target driving route P is obtained as the vehicle speed of the tractor 1.

In the automatic braking control, the braking control unit 182 determines whether the left and right handbrakes are activated at the left or right rear in the braking area included in the route data of the target travel route P, based on the target travel route P and the output of the positioning unit 21. The operation of the brake operating mechanism 15 is automatically controlled so as to appropriately brake the wheels 6.

In automatic steering control, the steering angle setting unit 184 determines and sets the target steering angles of 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. The power steering mechanism 14 automatically steers the left and right front wheels 5 based on the target steering angles and the output of the steering angle sensor 20 so that the target steering angles are obtained as the steering angles of the left and right front wheels 5.

In automatic control for work, the work equipment control unit 183 determines whether the tractor 1 is working at the starting end of the work route P1 (for example, see FIG. 3) based on the route data of the target traveling route P and the output of the positioning unit 21. When the tractor 1 reaches the start point, a predetermined work (for example, plowing work) is started by the work device 12, and when the tractor 1 reaches the work end point such as the end of the work route P1 (see FIG. 3, for example). Accordingly, the operations of the clutch operating mechanism 16 and the lifting drive mechanism 17 are automatically controlled so that the predetermined work performed by the working device 12 is stopped.

In this way, in the tractor 1, the transmission 13, the power steering mechanism 14, the brake operation mechanism 15, the clutch operation mechanism 16, the lifting drive mechanism 17, the on-vehicle electronic control unit 18, the vehicle speed sensor 19, the steering angle sensor 20, the positioning The automatic traveling unit 2 is configured by the unit 21, the communication module 25, and the like.

In this embodiment, it is possible not only to cause the tractor 1 to travel automatically without a user or the like boarding the cabin 10, but also to drive the tractor 1 automatically with a user or the like boarding the cabin 10. Therefore, not only can the tractor 1 be automatically driven along the target traveling route P by the automatic driving control by the on-vehicle electronic control unit 18 without the user or the like boarding the cabin 10, but also the user or the like can board the cabin 10. Even in this case, the tractor 1 can automatically travel along the target travel route P by the automatic travel control by the on-vehicle electronic control unit 18.

When a user or the like is in the cabin 10, the on-vehicle electronic control unit 18 switches between an automatic driving state in which the tractor 1 travels automatically and a manual driving state in which the tractor 1 travels based on the user's driving. be able to. Therefore, while the vehicle is automatically traveling along the target travel route P in the automatic travel state, it is possible to switch from the automatic travel state to the manual travel state,
Conversely, while the vehicle is traveling in the manual traveling state, it is possible to switch from the manual traveling state to the automatic traveling state. For switching between the manual driving state and the automatic driving state, for example, a switching operation section 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 section can be carried. It can also be displayed on the display unit 51 of the communication terminal 3. Further, when the user operates the steering wheel 38 during automatic driving control by the on-vehicle electronic control unit 18, the automatic driving state can be switched to the manual driving state.

As shown in FIGS. 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 collisions with the obstacles. ing. The obstacle detection system 100 includes a plurality of lidar sensors (an example of a distance measuring section) 101 and 102 that can three-dimensionally measure the distance to a distance measuring point using a laser, and a plurality of lidar sensors (an example of a distance measuring section) 101 and 102 that can measure the distance to a distance measuring point using an ultrasonic wave. It includes sonar units 103 and 104 having a plurality of sonar capable of measuring distance, an obstacle detection section 110, and a collision avoidance control section 111. Here, the distance measurement points measured by the lidar sensors 101, 102 and the sonar units 103, 104 are objects, people, etc.

The obstacle detection unit 110 performs obstacle detection processing to detect distance measurement points such as objects or people within a predetermined distance as obstacles based on measurement information from the lidar sensors 101 and 102 and the sonar units 103 and 104. It is composed of The collision avoidance control unit 111 is configured to perform collision avoidance control when the obstacle detection unit 110 detects an obstacle. The obstacle detection unit 110 repeatedly performs obstacle detection processing in real time based on measurement information from lidar sensors 101, 102 and sonar units 103, 104, appropriately detects obstacles such as objects and people, and avoids collisions. The control unit 111 performs collision avoidance control to avoid collisions with obstacles detected in real time.

The obstacle detection section 110 and the collision avoidance control section 111 are included in the on-vehicle electronic control unit 18. The onboard electronic control unit 18 is communicably connected to an engine electronic control unit, lidar sensors 101, 102, sonar units 103, 104, etc. included in the common rail system via a CAN (Controller Area Network). ing.

The lidar sensors 101 and 102 irradiate the surrounding area with laser light (for example, pulsed near-infrared laser light) as measurement light, and receive reflected light of the laser light, and the measurement light is reflected at a distance measurement point. The distance to the distance measurement point is measured from the round trip time until the time of flight. The lidar sensors 101 and 102 measure the distance to the distance measurement point in three dimensions by scanning laser beams at high speed in the vertical and horizontal directions and sequentially measuring the distance to the distance measurement point at each scanning angle. Measuring. The lidar sensors 101 and 102 repeatedly measure the distance to the distance measurement point within the obstacle detection area in real time. The lidar sensors 101 and 102 are configured to be able to generate a distance image from measurement information and output it to the outside. The distance image generated from the measurement information of the lidar sensors 101 and 102 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 so that the user or the like can visually confirm the presence or absence of obstacles. Can be done. Incidentally, in a distance image, distances in far and near directions can be indicated using colors or the like, for example.

As shown in Figures 11 and 12, the lidar sensors 101, 102 include a front lidar sensor 101 that has a distance measurement range C in front of the tractor 1 (running body 7) and is used to detect obstacles in front of the tractor 1, and a rear lidar sensor 102 that has a distance measurement range D in the rear of the tractor 1 (running body 7) and is used to detect obstacles in the rear of the tractor 1.

The front lidar sensor 101 and the rear lidar sensor 102 will be explained below, including the support structure of the front lidar sensor 101, the support structure of the rear lidar sensor 102, the distance measurement range C of the front lidar sensor 101, and the distance measurement range of the rear lidar sensor 102. The explanation will be given in order of D.

The support structure of the front lidar sensor 101 will be explained.
As shown in FIGS. 1 and 7, the front lidar sensor 101 is attached to the bottom of the antenna unit 80 located at the upper part of the front side of the cabin 10. First, the support structure of the antenna unit 80 will be explained. Next, a structure for attaching the front lidar sensor 101 to the bottom of the antenna unit 80 will be explained.

4, 6 and 7, the antenna unit 80 is attached to a pipe-shaped antenna unit support stay 81 that extends over 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 that corresponds 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 in a state that spans the left and right mirror mounting parts 45 that are located diagonally forward on the left and right sides of the cabin 10. The mirror mounting part 45 includes a mirror mounting base 46 fixed to the front support 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 part 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 portion of the mirror mounting bracket 47 via the first mounting plate 201. As shown in FIG. 6 and FIG. 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. The antenna unit support stay 81 is fixedly connected in a position extending horizontally by fastening the two mounting surfaces with a connecting tool 50 such as a bolt nut in a state where the two mounting surfaces are overlapped one on the other. The antenna unit 80 is supported by the front support 36 constituting 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 vibration to the antenna unit 80.

Regarding the attachment structure of the antenna unit 80 to the antenna unit support stay 81, as shown in FIG. 6 and FIG. The antenna unit 80 is attached to the antenna unit support stay 81 by fastening the antenna unit 80 to the third attachment plate 203 using a connector 50 such as a bolt or nut.

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 at a predetermined distance in the left-right direction. The second mounting plate 202 is configured as an L-shaped bent plate having a stay side mounting portion 202b extending downward from the outer end of the 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 in the figure, the stay side mounting portion 202b of the second mounting plate 202 has a pair of round holes formed in the front and rear for connection by a connector or the like.

As shown in FIGS. 6 and 7, the third mounting plate 203 is formed of an L-shaped plate-like body in which the front side portion extends further downward than the rear side portion. Similar to the second mounting plate 202, the third mounting plate 203 is provided in a pair on the left and right 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 end edge of the rear part is fixedly connected to the upper part of the antenna unit support stay 81 by welding or the like, and the front part is positioned in front of the antenna unit support stay 81. . The third mounting plate 203 is formed with a long elongated hole 203a extending along the longitudinal direction of the traveling body 7 from the front side part to the rear side part, and a round hole for connection on the lower side of the front side part. 203b is formed.

When attaching the antenna unit 80 to the antenna unit support stay 81, as shown in FIGS. 6 and 7, the antenna unit 80 is placed above the antenna unit support stay 81 so that the antenna of the communication module 25 is position in the use position extending to the side. The second mounting plate 202 is attached to the third mounting plate 202 so that the front and rear round holes in the stay-side mounting portion 202b of the second mounting plate 202 match the front and rear ends of the elongated hole 203a of the third mounting plate 203. The second mounting plate 202 and the third mounting plate 203 are placed on top of each other in a state in which they are positioned on the inner side of the mounting plate 203. By inserting the connector 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 and fastening them, the antenna unit 80 can be attached to the antenna unit support stay 81 at the use position. Can be installed. At this time, locations corresponding to the front end and rear end of the elongated hole 203a are set as connection locations by the connector 50, and each of the pair of left and right second mounting plates 202 and third mounting plates 203 A total of four locations, the front side portion and the rear side portion, are connection points by the connector 50.

As shown in FIG. 6, the antenna unit 80 is not only in the use position, but also as shown in FIG. It is configured such that it can be freely attached to the antenna unit support stay 81 even in the non-use position where it extends.

When attaching the antenna unit 80 to the antenna unit support stay 81 in a non-use position, as shown in FIG. The second mounting plate 202 is positioned inward from the third mounting plate 203 so that the front and rear round holes match the front ends of the round hole 203b and long hole 203a of the third mounting plate 203. The second mounting plate 202 and the third mounting plate 203 are overlapped. The connector 50 is inserted through the front round hole in the stay side attachment part 202b of the second attachment plate 202 and the round hole 203b of the third attachment plate 203, and the connector 50 is inserted through the rear side in the stay side attachment part 202b of the second attachment plate 202. By inserting and fastening the connector 50 across the side round hole and the front end of the long hole 203a,
The antenna unit 80 can be attached to the antenna unit support stay 81 at a non-use position.

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. The connecting tool 50 located at the rear end of the elongated hole 203a of the third mounting plate 203 is loosened, and the state in which the connecting tool 50 is inserted into the elongated hole 203a is maintained. By moving the connector 50 forward along the elongated hole 203a from the rear end to the front end, the antenna unit 80 is suspended forward and downward using the connector 50 as a pivot axis, as shown in FIG. 8, the antenna unit 80 is moved to a non-use position. Therefore, the connector 50 is inserted through the front round hole of the second mounting plate 202 and the round hole 203b of the third mounting plate 203, and the connector 50 is inserted through the rear round hole of the second mounting plate 202 and the front of the elongated hole 203a. The connector 50 can be inserted and fastened across the side end portions, and the antenna unit 80 can be moved from the use position to the non-use position.

When the antenna unit 80 is installed in the use position, as shown in FIG. 9(a),
A part of the antenna unit 80 protrudes upward from the highest line Z passing through the highest part 35a of the roof 35, so that the antenna of the communication module 25 can be placed higher, and the wireless communication of the communication module 25 is improved. We make sure that we can do this properly. On the other hand, when the antenna unit 80 is installed in the non-use position, the upper end of the antenna unit 80 is placed at the same height as the highest line Z or from the highest line Z, as shown in FIG. 9(b). It is also placed in a low position. As a result, when transporting the tractor 1 or storing the tractor 1 in a storage location such as a barn, the antenna unit 80 does not protrude above the highest line Z, and the antenna unit 80 does not get in the way. It is possible to prevent the antenna unit 80 from being damaged due to contact with an obstacle or the like.

As shown in FIG. 7, the mounting structure of the front rider sensor 101 to the antenna unit 80 is such that the front rider sensor 101 is attached to the bottom of the antenna unit 80 by fastening the fourth mounting plate 204 and the fifth mounting plate 205 with a connecting tool 50 such as a bolt nut. The fourth mounting plate 204 has a mounting surface portion 204a extending in the left-right direction, and both ends of the mounting surface portion 204a are formed in a bridge shape extended downward. The fifth mounting plate 205 has a pair of left and right mounting surface portions 205a facing each other in the left-right direction, and is formed in a bridge shape in which the upper ends of the mounting surface portions 205a are connected to each other. The mounting surface portion 204a of the fourth mounting plate 204 is fixedly connected to the bottom of the antenna unit 80 by the connecting tool 50. The front side portion of the fourth mounting plate 204 and the rear side portion of the fifth mounting plate 205 are fixedly connected to each other by the connecting tool 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 rider sensor 101 by connectors 50. The front rider 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.

As shown in FIG. 7, the front lidar sensor 101 is configured to be detachably attached to the antenna unit 80 via a fourth attachment plate 204 and a fifth attachment plate 205. It is also possible to retrofit the front rider sensor 101, and it is also possible to remove only the front rider sensor 101. Further, the antenna unit 80 is also configured to be detachable from the mirror mounting portion 45 via the antenna unit support stay 81, so that the front lidar sensor 101 can be attached to and detached from the traveling aircraft 7 by itself. In addition, it can also be attached to and detached from the traveling aircraft 7 together with the antenna unit 80. The front lidar sensor 101 uses the antenna unit support stay 81 that supports the antenna unit 80 as a common support stay, and similarly to the antenna unit 80, the front lidar sensor 101 uses a It is strongly supported.

Since the front lidar 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 lidar sensor 101 can be adjusted as shown in FIG. As shown in FIG. 8, there is a use position where the traveling body 7 faces forward and is used for detecting obstacles in front of the traveling body 7, and a non-use position where it faces downward and is not used for obstacle detection as shown in FIG. It is configured so that its position can be changed freely.

When the front rider sensor 101 is located at the use position, as shown in FIGS. 6 and 9(a), the front rider sensor 101 is located at the entrance/exit step which becomes the entrance/exit part to the cabin 10 (driver's seat 39) in the vertical direction. 41 (see FIG. 1), and is located at a position corresponding to the roof 35. The front rider sensor 101 is attached in a forward-sloping posture, with the front part being located further downward. The front lidar sensor 101 is provided so as to measure the front side of the traveling aircraft 7 while looking down from diagonally above. The antenna unit support stay 81 is arranged at a position overlapping with the front end portion 35b of the roof 35 in the longitudinal direction of the traveling body 7, and at a position near the front end portion 35b of the roof 35 in the vertical direction, so that the front rider sensor 101 is arranged in the vicinity of the front end part 35b of the roof 35 on the diagonally upper front side by utilizing the space below the antenna unit 80. As a result, as shown in FIG. 11, from the line of sight of the passenger T seated in the driver's seat 39, at least a portion of the front rider sensor 101 overlaps with the front end portion 35b of the roof 35. The front rider sensor 101 is arranged at a position where at least a portion of the front rider sensor 101 is hidden by the front end portion 35b of the roof 35. A part of the front rider sensor 101 is located outside the visible range B1 in front of the passenger T seated in the driver's seat 39, and the front rider sensor 101 is partially out of the visible range B1 of the passenger T seated in the driver's seat 39. It is possible to suppress the obstruction caused by

When the front lidar sensor 101 is located at the non-use position, as shown in FIGS. 8 and 9(b), the upper end of the front lidar sensor 101 is connected to the highest line Z, similar to the antenna unit 80.
(See FIG. 9(b)). This prevents not only the antenna unit 80 but also the front rider sensor 101 from protruding above the highest line Z when transporting the tractor 1 or storing the tractor 1 in a storage location such as a barn. are doing.

Regarding the arrangement position of the front lidar sensor 101, in the left-right direction of the traveling body 7, it is arranged at the center of the antenna unit 80 in the left-right direction. Since the antenna unit 80 is arranged at a position corresponding to the center of the cabin 10 in the left-right direction of the traveling body 7, the front lidar sensor 101 is also arranged at a position corresponding to the center of the cabin 10 in the left-right direction of the traveling body 7. It is located in

As shown in FIGS. 6 and 7, on the fifth mounting plate 205, in addition to the front lidar sensor 101, a front camera 108 whose imaging range is the front side of the traveling body 7 is attached by a connector or the like. The front camera 108 is arranged above the front lidar sensor 101. The front camera 108, like the front lidar sensor 101, is attached in a forward-sloping posture, with the front side located further downward. The front camera 108 is provided to take an image of the front side of the traveling body 7 while looking down from diagonally above. It is configured such that the captured image captured by the front camera 108 can be outputted to the outside. The image taken by the front camera 108 can be displayed on a display device such as the display section of the tractor 1 or the display section 51 of the mobile communication terminal 3, so that the user or the like can visually confirm the situation around the tractor 1.

Next, a support structure for the rear rider sensor 102 will be explained.
The rear rider sensor 102 is attached to a pipe-shaped sensor support stay 301 that spans the entire length of the cabin 10 in the left-right direction of the traveling body 7, as shown in FIGS. 5 and 10. The rear rider sensor 102 is arranged at a position corresponding to the center of the cabin 10 in the left-right direction of the traveling body 7.

As shown in FIGS. 5 and 10, the sensor support stay 301 is fixedly connected to the left and right rear columns 37 located at both left and right ends of the cabin 10. The sensor support stay 301 is formed into a bridge shape in plan view with both left and right end portions curved diagonally forward. Both left and right ends of the sensor support stay 301 are fixedly connected to mounting members provided at the upper end portions of the left and right rear columns 37 via a sixth mounting plate 206 . A sixth mounting plate 206 is fixedly connected to both left and right ends of the sensor support stay 301 by welding or the like. By fastening the sixth mounting plate 206 and a mounting member provided at the upper end portion of the rear support column 37 using the connector 50, the sensor support stay 301 is fixedly connected in a horizontally extending posture.

As shown in FIG. 10, the rear rider sensor 102 is attached to the sensor support stay 301 through a seventh attachment plate 207 and an eighth attachment plate 208. . The seventh mounting plate 207 has a pair of left and right side wall portions 207a that face each other in the left and right direction, and is formed in a bridge shape in which the upper ends of the side wall portions 207a are connected to each other. The eighth mounting plate 208 has a pair of left and right mounting surface portions 208a that face each other in the left-right direction, and is formed in a bridge shape in which the upper ends of the mounting surface portions 208a are connected to each other. The lower edge of the side wall surface portion 207a of the seventh mounting plate 207 is fixedly connected to the sensor support stay 301 by welding or the like. The rear side portion of the seventh attachment plate 207 and the front side portion of the eighth attachment plate 208 are fixedly connected by a connector 50. A pair of left and right mounting surfaces 208 a of the eighth mounting plate 208 are fixedly connected to both lateral sides of the rear rider sensor 102 by a connecting tool 50 . The rear rider sensor 102 is
It is attached so that it is sandwiched between the left and right attachment surfaces 208a of the eighth attachment plate 208 in the left-right direction. A reinforcing plate 302 is fixedly connected to the front side portion of the seventh mounting plate 207 by a connecting tool or the like. A front portion of the reinforcing plate 302 is fixedly connected to the upper surface of the roof 35 by a connecting member 50. The reinforcing plate 302 has a U-shape with standing walls bent upward at both ends in the left-right direction, and extends in the front-rear direction, and extends between the roof 35, the seventh mounting plate 207, and the sensor support stay 301. It is equipped.

As shown in FIGS. 9(b) and 10, the rear lidar sensor 102 is configured to
It is arranged at a position higher than the getting on/off step 41 (see FIG. 1) and corresponding to the roof 35. The rear rider sensor 102 is attached to the sensor support stay 301 in a backward-sloping posture, with the rearward portion being positioned further downward. The rear rider sensor 102 is provided so as to measure the rear side of the traveling aircraft 7 while looking down from diagonally above. The sensor support stay 301 is disposed near the rear end portion 35c of the roof 35 in the longitudinal direction of the traveling body 7, and at a position overlapping the rear end portion 35c of the roof 35 in the vertical direction, so that the rear rider The sensor 102 is disposed at approximately the same height as the rear end portion 35c of the roof 35, or at a position near the rear end portion 35c on the diagonally upper side. As a result, as shown in FIG. 11, from the line of sight of the passenger T seated in the driver's seat 39, at least a portion of the rear rider sensor 102 overlaps with the rear end portion 35c of the roof 35. The rear rider sensor 102 is arranged at a position where at least a portion of the rear rider sensor 102 is hidden by the rear end portion 35c of the roof 35. For the passenger T seated in the driver's seat 39, a part of the rear rider sensor 102 is located outside the visible range B2 on the rear side, and the field of view of the passenger T seated in the driver's seat 39 is limited to the rear rider sensor. 102 can be prevented from being blocked.

As shown in FIG. 10, the rear rider sensor 102 is configured to be detachably attached to the rear column 37 via a sensor support stay 301, a seventh attachment plate 207, and an eighth attachment plate 208. It is also possible to retrofit the rear rider sensor 102, and it is also possible to remove the rear rider sensor 102. Since the rear rider sensor 102 is supported by the rear column 37 that constitutes the cabin frame 31 via the sensor support stay 301,
It is firmly supported while preventing vibrations from being transmitted to the rear rider sensor 102.

As shown in FIG. 10, on the eighth mounting plate 208, in addition to the rear rider sensor 102, a rear camera 109 whose imaging range is the rear side of the traveling body 7 is attached by a connector or the like. The rear camera 109 is arranged above the rear lidar sensor 102. The rear camera 109, like the rear lidar sensor 102, is attached in a backward-sloping posture, with the rearward portion being located further downward. The rear camera 109 is provided to take an image of the rear side of the traveling aircraft 7 while looking down from diagonally above. It is configured such that the captured image captured by the rear camera 109 can be outputted to the outside. The image captured by the rear camera 109 can be displayed on a display device such as the display section of the tractor 1 or the display section 51 of the mobile communication terminal 3, so that the user or the like can visually confirm the situation around the tractor 1.

The distance measurement range C of the front lidar sensor 101 will be explained.
The front lidar sensor 101 has a left and right ranging range C1 in the left-right direction, as shown in FIG. 12, and a vertical ranging range C2 in the up-down direction, as shown in FIG. As a result, the front lidar sensor 101 can detect up and down, left and right, and front and back included in the left and right distance measurement range C1 and the upper and lower distance measurement range C2, in the range up to the first set distance X1 (see FIG. 12) from the front lidar sensor 101. A rectangular pyramid-shaped ranging range C is set.

As shown in FIG. 12, the left and right ranging range C1 of the front lidar 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 and right distance measurement range C1 is set within a range of a first set angle α1 between a first boundary line E1 and a second boundary line E2 extending from the front lidar sensor 101. In this way, the front lidar sensor 101 has the left and right ranging ranges C1, but does not use the entire left and right ranging ranges C1 as the obstacle detection range, but uses the center side of the left and right ranging ranges C1 as the obstacle detection range. It is said that In the left and right ranging range C1, an obstacle detection area J for detecting obstacles is set on the center side of the traveling aircraft 7 in the left and right direction, and a non-detection area for detecting obstacles is set outside the obstacle detection area J. Area K is set. As a result, the range in which the obstacle detection unit 110 detects obstacles in the obstacle detection process based on the measurement information of the front lidar sensor 101 is the obstacle detection region J in the left and right direction. The obstacle detection area J is set in the left-right direction of the traveling body 7 to a position that is a second set distance X2 on both left and right sides from the center of the traveling body 7 as a reference. The obstacle detection area J is set in a range larger than the width of the tractor 1 and the width of the working device 12 in the width direction of the traveling body 7. The size of the obstacle detection area J can be changed as appropriate. For example, by arbitrarily changing the second set distance X2, the size of the obstacle detection area J can be changed. can do.

As shown in FIG. 11, the vertical measurement range C2 of the front lidar sensor 101 is set within the range of the second set angle α2 between the third boundary line E3 and the fourth boundary line E4 extending from the front lidar sensor 101. The third boundary line E3 is set as a horizontal line extending horizontally forward from the front lidar sensor 101, and the fourth boundary line E4 is set as a straight line located below the first tangent line G1 from the front lidar sensor 101 to the front upper part of the front wheel 5. The vertical measurement range C2 is set so that the first center line F1 between the third boundary line E3 and the fourth boundary line E4 is located above the bonnet 8, ensuring a sufficiently large obstacle detection area above the bonnet 8. By setting the fourth boundary line E4 below the first tangent line G1, it is possible to measure the measurement point of an object, person, etc. even if the measurement point is present in a position near the front end of the traveling body 7 (the front end of the bonnet 8).

As shown in FIG. 11, a part of the bonnet 8 and a part of the front wheel 5 are included in the vertical distance measuring range C2 of the front lidar sensor 101. If the obstacle detection process is performed based on the measurement information, there is a possibility that part of the hood 8 or part of the front wheel 5 will be erroneously detected as an obstacle. Therefore, a first masking process is performed to prevent such false detection. In the first masking process, within the distance measurement range C of the front lidar sensor 101, a range where a part of the bonnet 8 and a part of the front wheel 5 are present is masked in a masking range L (see FIG. 13 ) is set in advance.

For example, in the first masking process, as a pre-processing using the front LIDAR sensor 101,
Measurement is actually performed by the front lidar sensor 101, and a distance image generated from the measurement information 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 distance image on the display device to set a masking range L in which the obstacle is not detected. As shown in FIG. 13, when a part of the hood 8 and a part of the front wheel 5 are present on the distance image, the masking range L is set based on a reference range including a range La in which the part of the hood 8 is present and a range Lb in which a part of the front wheel 5 is present. The front wheel 5 is steered left and right by the operation of the steering wheel 38, the power steering mechanism 14, etc. as shown by the dotted line in FIG. 13, so it is preferable to set the masking range L so as to include the steering range in which the front wheel 5 is steered left and right.

In what is shown in FIG. 13, a chevron-shaped range that is larger by a set range than a reference range that includes a range La where a part of the bonnet 8 exists and a range Lb where a part of the front wheel 5 exists is set as a masking range L. are doing. Incidentally, the masking range L is set as a three-dimensional range in the front-rear direction, left-right direction, and up-down direction. The masking range L is set to a shape according to the shape of the bonnet 8 and the front wheels 5, for example, so as to include only the range La where a part of the hood 8 exists and the range Lb where a part of the front wheels 5 exist. The range and shape of the masking range L can be changed as appropriate.

In this way, the obstacle detection unit 110 performs obstacle detection processing based on the measurement information of the front lidar sensor 101, so that the object is included in the obstacle detection area J (see FIG. 12) in the left and right direction, and The presence or absence of an obstacle is detected in the range included in the vertical ranging range C2 (see FIG. 11) in the vertical direction, excluding the masking range L.

The distance measurement range D of the rear lidar sensor 102 will be explained.
Like the front lidar sensor 101, the rear lidar sensor 102 has a left and right ranging range D1 in the left and right direction, as shown in FIG. 12, and a vertical ranging range D1 in the up and down direction, as shown in FIG. It has D2. As a result, the rear lidar sensor 102 can detect up and down, left and right, and front and back included in the left and right distance measurement range D1 and the upper and lower distance measurement range D2 in the range up to the third set distance X3 (see FIG. 12) from the rear lidar sensor 102. A rectangular pyramid-shaped ranging range D is set. Incidentally, X1 and X3 can be set to the same distance or different distances.

As shown in FIG. 12, the left-right distance measurement range D1 of the rear LIDAR sensor 102 is set within the range of a third set angle α3 between the fifth boundary line E5 and the sixth boundary line E6 extending from the rear LIDAR sensor 102, similar to the front LIDAR sensor 101. Within the left-right distance measurement range D1, an obstacle detection area J is set at the center of the traveling body 7 in the left-right direction, and a non-detection area K is set outside the obstacle detection area J. The obstacle detection unit 110 detects obstacles in the obstacle detection process based on the measurement information of the rear LIDAR sensor 102 within the obstacle detection area J in the left-right direction.

As shown in FIG. 11, the vertical distance measuring range D2 of the rear lidar sensor 102 is set within the range of the fourth set angle α4 between the seventh boundary line E7 and the eighth boundary line E8 extending from the rear lidar sensor 102. ing. Since the working device 12 is equipped to be able to move up and down between the raised position and the lowered position, in FIG. 12 is indicated by a dotted line. The seventh boundary line E7 is set as a horizontal line extending horizontally backward from the rear rider sensor 102, and the eighth boundary line E8 is
The line is set to be a straight line located lower than the second tangent line G2 from the rear rider sensor 102 toward the rear upper part of the working device 12 located in the lowered position. In the vertical ranging range D2, the second center line F2 between the seventh boundary line E7 and the eighth boundary line E8 is located above the working device 12 in the raised position (indicated by the dotted line in FIG. 11). A sufficiently large obstacle detection area is secured above the working device 12 in the raised position. By setting the eighth boundary line E8 below the second tangent line G2, even if the distance measurement point of an object or person exists near the rear end of the working device 12 in the lowered position, , the distance measurement point can be measured.

Since a part of the working device 12 is in the vertical distance measurement range D2 of the rear lidar sensor 102, when the obstacle detection unit 110 performs obstacle detection processing based on the measurement information of the rear lidar sensor 102, There is a possibility that a part of the working device 12 may be erroneously detected as an obstacle. Therefore, a second masking process is performed to prevent such false detection. In the second masking process, within the distance measurement range D of the rear lidar sensor 102, a range where a part of the working device 12 exists is set as a masking range L (see FIGS. 14 and 15) where no obstacle is detected. It is set in advance.

For example, in the second masking process, as in the first masking process, as a pre-processing before using the rear LIDAR sensor 102, measurements are actually performed using the rear LIDAR sensor 102, and a distance image generated from the measurement information 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 distance image on the display device to set a masking range L in which no obstacles are detected.

The working device 12 is raised and lowered between a lowered position and a raised position. The tractor 1 lowers the working device 12 to a lowered position and travels while performing a predetermined work, and raises the working device 12 to a raised position and only travels without performing any predetermined work. Therefore, in the second masking process, as the masking range L, as shown in FIG. 14, a masking range L1 for the lowered position is set, and as shown in FIG. 15, a masking range L2 for the raised position is set. 14 and 15, the part of the working device 12 that is within the distance measurement range D of the rear lidar sensor 102 is shown by a solid line, and the part that is outside the distance measurement range D of the rear lidar sensor 102 is shown by a dotted line. It is shown in By operating the lifting operation tool in the cabin 10, the working device 12 is positioned at the lowered position, and masking for the lowered position is performed using a distance image generated from the measurement information of the rear lidar sensor 102 at that time. Range L1 is set. By operating the lifting operation tool in the cabin 10, the work device 12 is positioned at the raised position, and masking for the raised position is performed using a distance image generated from the measurement information of the rear lidar sensor 102 at that time. Range L2 is set.

In what is shown in FIGS. 14 and 15, rectangular ranges that are larger by a set range than the reference range including the range Lc where the work device 12 exists are set as masking ranges L1 and L2.
Incidentally, the masking range L is set as a three-dimensional range in the front-rear direction, left-right direction, and up-down direction. The masking range L can be set to a shape according to the shape of the work device 12, for example, so as to include only the range Lc where the work device 12 exists, and the masking ranges L1 and L2 can be set to any range and shape. It is possible to change it as appropriate.

In this way, the obstacle detection unit 110 performs obstacle detection processing based on the measurement information of the rear lidar sensor 102, so that the object is included in the obstacle detection area J (see FIG. 12) in the left and right direction, and The presence or absence of an obstacle is detected in the range included in the vertical distance measurement range D2 (see FIG. 11) in the vertical direction, excluding the masking ranges L1 and L2. When the working device 12 is located at the lowered position, the obstacle detection unit 110 performs obstacle detection processing using the masking range L1 for the lowered position, and when the working device 12 is located at the raised position, the obstacle detection unit 110 performs obstacle detection processing using the masking range L1 for the lowered position. Obstacle detection processing is performed using the masking range L2.

The sonar units 103 and 104 will be explained below.
The sonar units 103 and 104 are configured to measure the distance to the distance measurement point based on the round trip time until the projected ultrasonic wave hits the distance measurement point and bounces back.

As shown in FIG. 12, the sonar units 103 and 104 include a right-side sonar unit 103 whose obstacle detection area is the right side of the tractor 1 (traveling body 7), and a sonar unit 103 whose obstacle detection area is the right side of the tractor 1 (traveling body 7), as shown in FIG. ) is provided with a left sonar unit 104 whose obstacle detection area is the left side of the vehicle.

As shown in FIG. 12, the obstacle detection area N of the right sonar unit 103 and the obstacle detection area N of the left sonar unit 104 extend from the traveling aircraft 7 in opposite directions. The only difference is that the obstacle detection areas N on the right and left sides are symmetrical.

Sonar units 103, 104 use the outside of the traveling body 7 as a distance measurement point. Sonar units 103, 104 are attached to the traveling body 7 so as to project ultrasonic waves downward at a predetermined angle from the horizontal direction, and an obstacle detection area N is set so as to extend in a direction facing downward at a predetermined angle from sonar units 103, 104. Obstacle detection area N of sonar units 103, 104 is a range whose radius is a distance from sonar units 103, 104 to a predetermined distance outward from traveling body 7, and is set between left and right distance measurement range C1 of front lidar sensor 101 and left and right distance measurement range D1 of rear lidar sensor 102 in the fore-and-aft direction of traveling body 7.

In this way, the obstacle detection unit 110 detects the presence or absence of an obstacle in the left and right obstacle detection areas N by performing obstacle detection processing based on the measurement information of the sonar units 103 and 104. .

The collision avoidance control by the collision avoidance control unit 111 will be explained below. First, the collision avoidance control when an obstacle is detected in the obstacle detection process based on the measurement information of the lidar sensors 101 and 102 will be explained, and then the collision avoidance control will be explained. Collision avoidance control when an obstacle is detected in obstacle detection processing based on measurement information of the sonar units 103 and 104 will be described.

Two lidar sensors, a front lidar sensor 101 and a rear lidar sensor 102, are provided as lidar sensors, and the obstacle detection unit 110 switches between forward and backward travel at a forward/reverse switching point included in the target travel route P. Alternatively, the obstacle detection state is switched based on switching between forward and backward travel using a reverser lever provided inside the cabin 10 for switching between forward and backward travel. When the tractor 1 travels forward, the front lidar sensor 101 performs measurement, the obstacle detection unit 110 switches to the forward detection state in which obstacle detection processing is performed based on the measurement information of the front lidar sensor 101, and the tractor 1 travels backward. When the vehicle is running, the rear rider sensor 102 performs measurement, and the obstacle detection section 110 switches to a backward detection state in which obstacle detection processing is performed based on measurement information from the rear rider sensor 102. In this way, depending on whether the tractor 1 is traveling forward or backward, the processing load can be reduced by switching which lidar sensor, the front lidar sensor 101 or the rear lidar sensor 102, is used to detect obstacles. We are trying to detect obstacles while trying to reduce this.

In the forward motion detection state, the obstacle detection unit 110 performs obstacle detection processing based on the measurement information of the front lidar sensor 101, and detects obstacles that are included in the obstacle detection area J (see FIG. 12) in the left and right direction and in the vertical direction. In the range included in the upper and lower ranging range C2 (see FIG. 11), the presence or absence of an obstacle is detected in the range excluding the masking range L (see FIG. 13). In the backward motion detection state, when the work device 12 is located at the lowered position, the obstacle detection section 110 performs obstacle detection processing based on the measurement information of the rear rider sensor 102, and detects the obstacle detection area J ( 12), and in the range included in the vertical distance measurement range D2 (see Fig. 11), excluding the masking range L1 for the descending position (see Fig. 14), the presence or absence of obstacles. is being detected. In the backward motion detection state, when the working device 12 is located at the raised position, the obstacle detection unit 110 performs obstacle detection processing based on the measurement information of the rear rider sensor 102, and detects the obstacle detection area J ( 12), and in the range included in the vertical distance measurement range D2 (see Fig. 11), excluding the masking range L2 for the ascending position (see Fig. 15), the presence or absence of obstacles. is being detected.

When an obstacle is detected using the front lidar sensor 101 or the rear lidar sensor 102, collision avoidance is performed depending on in which range of the obstacle detection area J the obstacle is detected, as shown in FIG. The content of collision avoidance control by the control unit 111 is set to be different. The obstacle detection area J is divided into three areas, a first obstacle detection area J1, a second obstacle detection area J2, and a third obstacle detection area J3, depending on the distance from the front lidar sensor 101 or the rear lidar sensor 102. A range has been set. The first obstacle detection area J1 is a range in which the distance from the front lidar sensor 101 or the rear lidar sensor 102 is from the fourth set distance X4 to the first set distance X1 or from the fourth set distance X4 to the third set distance X3. is set to . The distance of the second obstacle detection area J2 from the front rider sensor 101 or the rear rider sensor 102 is set in a range from the fifth set distance X5 to the fourth set distance X4. The third obstacle detection area J3 is set in a range where the distance from the front rider sensor 101 or the rear rider sensor 102 is up to the fifth set distance X5. Therefore, for the tractor 1 including the front rider sensor 101, the rear rider sensor 102, and the working device 12, the first obstacle detection area J1, the second obstacle detection area J2, and the third obstacle detection area J3 are They are set to become closer in order.

The content of the collision avoidance control when an obstacle is detected using the front rider sensor 101 or the rear rider sensor 102 is the same whether the tractor 1 is traveling forward or backward, and is therefore as follows. , a case where the tractor 1 is traveling forward will be explained.

As shown in FIG. 12, when the tractor 1 is traveling forward and is in the first obstacle detection state in which an obstacle is detected within the first obstacle detection area J1 in the obstacle detection process, As collision avoidance control, the collision avoidance control unit 111 controls a notification device 26 such as a notification buzzer or a notification lamp to perform first notification control to notify the presence of an obstacle within the first obstacle detection area J1. conduct. In the first notification control, for example, the collision avoidance control unit 111 controls the notification device 26 such that the notification buzzer is activated intermittently at a predetermined frequency and the notification lamp is lit in a predetermined color.

When an obstacle is detected within the second obstacle detection area J2 in the obstacle detection process, the collision avoidance control unit 111 controls the notification device 26 such as a notification buzzer or notification lamp as a collision avoidance control. A second notification control is performed to notify that an obstacle exists within the second obstacle detection area J2, and a first deceleration control is performed to reduce the vehicle speed of the tractor 1. In the second notification control, for example, the collision avoidance control unit 111 controls the notification device 26 such that the notification buzzer is intermittently activated at a predetermined frequency and the notification lamp is lit in a predetermined color. In the first deceleration control, for example, the collision avoidance control unit 111 obtains a predicted collision time until the tractor 1 collides with an obstacle, based on the current vehicle speed of the tractor 1, the distance to the obstacle, and the like. The collision avoidance control unit 111 controls the engine 9, transmission 13, brake operation mechanism 15, etc. so as to reduce the vehicle speed of the tractor 1 while maintaining the determined collision prediction time at the set time (for example, 3 seconds). It's in control.

When an obstacle is detected within the third obstacle detection area J3 in the obstacle detection process, the collision avoidance control unit 111 controls the notification device 26 such as a notification buzzer or notification lamp as a collision avoidance control. Third notification control is performed to notify that an obstacle exists within the third obstacle detection area J3, and stop control is performed to stop the tractor 1. In the third notification control, for example, the collision avoidance control unit 111 controls the notification device 26 to continuously operate the notification buzzer and light the notification lamp in a predetermined color. In the stop control, for example, the collision avoidance control unit 111 controls the brake operating mechanism 15 and the like to stop the tractor 1.

Incidentally, the predetermined frequency at which the notification buzzer is activated intermittently in the first notification control and the second notification control may be the same frequency or may be different frequencies. Furthermore, the predetermined colors for lighting the notification lamps in the first to third notification controls may be the same color or different colors. In the first to third notification controls, in addition to controlling the notification device 26 of the tractor 1, the collision avoidance control unit 111 detects the presence of an obstacle in any of the first to third obstacle detection areas J1 to J3. It is also possible to control the terminal electronic control unit 52 so as to cause the display section 51 of the mobile communication terminal 3 to display display content indicating the following.

For example, when an obstacle is detected in the first obstacle detection area J1, the collision avoidance control unit 111 performs the first notification control to notify the user, etc., that an obstacle exists in the first obstacle detection area J1. If the tractor 1 continues traveling as it is and the position of the obstacle moves from the first obstacle detection area J1 to the second obstacle detection area J2, the collision avoidance control unit 111 performs the 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 position of the obstacle moves from the second obstacle detection area J2 to the third obstacle detection area J3, the collision avoidance control unit 111 performs the stop control in addition to the third notification control to stop the tractor 1, and a collision between the tractor 1 and the obstacle can be appropriately avoided.

When the lidar sensors 101 and 102 are used, distance measuring points where people or the like are moving are also detected as obstacles. Therefore, even if an obstacle is detected within the obstacle detection area J, the obstacle may move out of the obstacle detection area J due to movement of the obstacle itself. Therefore, when the position of the obstacle deviates from the first obstacle detection area J1, the collision avoidance control section 111 basically ends the first notification control. When the position of the obstacle deviates from the second obstacle detection area J2, the collision avoidance control unit 111 basically ends the second notification control and increases the vehicle speed of the tractor 1 to the set vehicle speed. Thus, vehicle speed recovery control is performed to control the engine 9, transmission 13, etc. When the position of the obstacle deviates from the third obstacle detection area J3, the collision avoidance control unit 111 basically ends the third notification control while maintaining the tractor 1 in the stopped state. In this case, the automatic traveling of the tractor 1 can be restarted by commanding the user or the like to restart the automatic traveling of the tractor 1.

Next, collision avoidance control when an obstacle is detected in the obstacle detection process based on the measurement information of the sonar units 103 and 104 will be described.
The sonar units 103 and 104 are provided on the left and right sides, but the obstacle detection unit 110 detects all of the sonar units 103 and 104 on both the left and right sides when the tractor 1 is traveling forward or when the tractor 1 is traveling backwards. Obstacle detection processing is performed based on the measurement information.

When an obstacle is detected in the obstacle detection process based on the measurement information of the sonar units 103 and 104, the collision avoidance control unit 111 controls the notification device 26 such as a notification buzzer or notification lamp as collision avoidance control. Then, fourth notification control is performed to notify that an obstacle exists within the obstacle detection area N of either sonar unit 103 or 104, and second deceleration control is performed to reduce the vehicle speed of tractor 1. In the fourth notification control, for example, the collision avoidance control unit 111 controls the notification device 26 to intermittently operate the notification buzzer at a predetermined frequency and to light the notification lamp in a predetermined color. In the second deceleration control, for example, the collision avoidance control unit 111 controls the engine 9, the transmission 13, the brake operation mechanism 15, etc. so as to decelerate the vehicle speed of the tractor 1 to a set vehicle speed.

In this way, the obstacle detection system 100 uses the front lidar sensor 101 and the rear lidar sensor 102 to detect the presence or absence of obstacles in the front and rear sides of the traveling aircraft 7, and also uses the sonar units 103 and 104 to detect the presence or absence of obstacles in the front and rear sides of the traveling aircraft 7. It is possible to detect the presence or absence of obstacles on the left and right sides of the traveling body 7. In the obstacle detection system 100, when the obstacle detection unit 110 detects the presence of an obstacle, the collision avoidance control unit 111 performs collision avoidance control to notify the user etc. of the existence of the obstacle. In addition, 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, and the collision between the tractor 1 and the obstacle can be prevented. Collisions can be appropriately avoided.

In the automatic driving state, automatic driving control is performed by the on-vehicle electronic control unit 18, so the obstacle detection system 100 decelerates or stops the tractor 1, allowing the tractor 1 to travel automatically while avoiding collisions with obstacles. can be done. Even in a manual driving state, the obstacle detection system 100 notifies the user of the presence of an obstacle and supports driving to avoid a collision between the tractor 1 and the obstacle. Can be done.

Hereinafter, in the automatic driving state, the obstacle detection processing by the obstacle detection unit 110 based on the measurement information of the lidar sensors 101 and 102 will be explained along the processing flow shown in FIG. 16.

First, distance measurement data for each distance measurement point is acquired in the entire distance measurement ranges C and D of the front lidar sensor 101 and the rear lidar sensor 102 (step #01 in FIG. 16). Each distance measurement point is the smallest unit (pixel) having distance measurement data in a distance image generated from measurement information of the lidar sensors 101 and 102. The distance measurement data of each distance measurement point includes data regarding the straight line distance from the lidar sensors 101 and 102, the irradiation direction of the measurement light, the intensity of the reflected light received by the lidar sensor 101, etc. include.

Next, coordinate data of each distance measurement point is generated (step #02 in FIG. 16). Specifically, at each distance measurement point, the linear distance data and irradiation direction data included in the distance measurement data are the coordinates in the X direction along the left and right direction of the tractor 1, and the Y direction along the front and rear direction of the tractor 1. The coordinates are converted into coordinate data consisting of coordinates in the Z direction along the vertical direction of the tractor 1. Note that the coordinate data in the X direction and Y direction of the distance measurement point is data indicating the position of the distance measurement point in plan view, and the coordinate data in the Z direction of the distance measurement point indicates the height of the distance measurement point. This is the data shown.

Next, for each ranging point, at least one of the intensity of the reflected light from the ranging point received by the lidar sensors 101 and 102 and the straight-line distance to the ranging point measured by the lidar sensors 101 and 102 is calculated. As the non-obstacle determination processing to determine whether the distance measurement point is a non-obstruction, the single distance measurement point deletion processing (step #03 in FIG. 16) and the floating object determination processing (step #04 in FIG. 16) are performed. , and dirt determination processing (step #05 in FIG. 16) is performed.

In the individual distance measurement point deletion process (step #03 in FIG. 16), individual distance measurement points from which distance measurement data due to minute rain, insects, noise, etc. were obtained are deleted.
As shown in FIG. 20, based on a straight-line distance d measured at a certain distance-measuring point, the straight-line distances d1 to d8 of a plurality of distance-measuring points around that distance-measuring point are referenced, and Among the linear distances d1 to d8 of a plurality of distance measuring points, the number of distance measuring points whose difference from the straight line distance d of the reference distance measuring point is within a predetermined range is measured. If the number is less than a predetermined number (for example, two), it can be said that the straight line distance d of the reference distance measurement point is caused by minute rain, insects, noise, or the like. Taking advantage of this fact, in the independent distance measurement point deletion process, such a distance measurement point is determined to be the above-mentioned individual distance measurement point. In addition, regarding the distance measurement point determined to be a single distance measurement point in this way, in order to avoid being determined as an obstacle in later obstacle detection, the distance measurement data held by that distance measurement point is is deleted and treated as a ranging point with no data that is not used for obstacle detection.

In the floating object determination process (step #04 in FIG. 16), it is determined whether the distance measurement point that emits the reflected light is a floating object such as dust or dust floating in the air.
Referring to FIG. 18, the linear distance measured by lidar sensors 101 and 102 is from a predetermined first set distance b1 (for example, 30 cm) to a predetermined second set distance b2 (for example, 200 cm) that is larger than the first set distance b1. ), and the intensity of the reflected light received by the lidar sensors 101 and 102 is less than a predetermined setting intensity a (for example, 270 digits), the distance measurement points are located around the tractor 1 rather than an obstacle. It can be said that there is a high possibility that it is a floating object floating in the air. Therefore, in the floating object determination process, such a distance measurement point is determined to be a floating object.
In addition, for distance measurement points that are determined to be floating objects in this way, the distance measurement data held by that distance measurement point will be deleted in order to avoid being determined as an obstacle in later obstacle detection. It is treated as a distance measurement point without data that is not used for obstacle detection.

Further, the state of floating objects such as dust and dust around the tractor 1 also changes depending on environmental conditions such as temperature, humidity, and weather. From this, the configuration is configured to appropriately change whether or not to execute the floating object determination process, and the threshold values such as the set strength a, set distances b1, b2, etc. used when executing the floating object determination process, based on the above environmental conditions. I don't mind if you do.

In the dirt determination process (step #05 in FIG. 16), it is determined whether the distance measurement point that emits reflected light is dirt attached to the lidar sensors 101, 102.
Referring to FIG. 18, for distance measurement points where the distance measured by lidar sensors 101, 102 is less than a predetermined first set distance b1 (for example, 30 cm), it is possible that the distance is dirt attached to lidar sensors 101, 102. Highly sexual. Therefore, in the dirt determination process, such distance measurement points are determined to be dirt on the lidar sensors 101 and 102.

Furthermore, the proportion of the distance measurement points determined to be dirty in the entire distance image generated from the measurement information of the lidar sensors 101 and 102 is determined as the dirt ratio. Then, it is determined whether the dirt ratio is equal to or higher than a predetermined set dirt ratio (step #06 in FIG. 16). If the dirt ratio is equal to or higher than the set dirt ratio (yes in step #06 in FIG. 16), the display section 51 of the mobile communication terminal 3 will display "The sensor surface is dirty," as shown in FIG. 19, for example. A predetermined contamination alarm such as ” is output (step #07 in FIG. 16). This allows the user to recognize that the lidar sensors 101 and 102 are dirty, and motivates the user to remove the dirt. As a result, deterioration in accuracy and damage to the lidar sensors 101 and 102 due to dirt can be avoided.

Next, a grid map is created to identify the presence or absence of obstacles and their positions (step #08 in FIG. 16).
As shown in Fig. 21, the grid map is configured by dividing the range corresponding to the left and right distance measurement ranges C1, D1 (see Fig. 12) between the boundary lines E2, E5 and the boundary lines E1, E6 extending from the LIDAR sensors 101, 102 at a predetermined resolution. For example, the resolution of the left and right angles of the LIDAR sensors 101, 102 is set to 2°, and the resolution of the distance from the LIDAR sensors 101, 102 is set to 25 cm. Each grid in the grid map is composed of multiple distance measurement points, and the largest height data among the multiple distance measurement points included in the same grid is set as the height data of the grid. In addition, such a grid map is generated at a predetermined measurement time interval (e.g., 0.1 sec) of the LIDAR sensors 101, 102.

When the grid map is created as described above, a reference plane setting process is executed to set a reference plane corresponding to the earth's surface (step #09 in FIG. 16).
In this reference plane setting process, a grid corresponding to the ground surface is detected as the measured reference plane. For example, a grid map is referenced and a grid that is lower than the installation level (height) of the LIDAR sensors 101 and 102 by a predetermined width or more can be detected as the measured reference plane.
In other words, as described below, if there is a grid among the multiple grids surrounding the grid to be determined as an obstacle candidate that is lower than the installation level of the lidar sensors 101, 102 by a predetermined width or more, the height of that grid will be deemed to correspond to the measured reference surface, and the measured reference surface will be detected.

If such a measured reference plane can be detected, the measured reference plane is set as the set reference plane. Specifically, a plurality of (for example, five) distance images generated in a predetermined period up to the present time are referred to, and the detection frequency of the actual measurement reference plane is determined. If the detection frequency of this actual measurement reference plane is equal to or higher than a predetermined set frequency (for example, 3/5), the detected actual measurement reference plane is set as the set reference plane.

On the other hand, if the detection frequency of the actual measurement reference plane is less than the set frequency, it is determined that the actual measurement reference plane cannot be detected, and a predetermined virtual reference plane (for example, 10 cm above the wheel contact surface) is plane) is set as the setting reference plane. With this, the obstacle detection unit 110 can always obtain the set reference plane regardless of the state of the ground surface, and can reliably detect obstacles using the set reference plane.

Next, obstacle detection processing using the grid map is executed (step #10 in FIG. 16).
In this obstacle detection process, obstacles are detected in each grid making up the grid map based on the height of the grid from the set reference plane. Specifically, a grid whose height from the set reference plane is equal to or greater than a predetermined obstacle determination height is detected as an obstacle.

For example, grids are determined to be obstacle candidates in order from the front grid of the grid map toward the back. Then, five surrounding grids, consisting of one grid in front of the grid to be determined, two grids on the left and right of the grid to be determined, and two grids in front of the two grids on the left and right, are used as comparison targets. Then, if there are multiple grids detected as measured reference surfaces that are lower than the height of the grid to be determined by a predetermined width or more among the multiple grids to be compared, the grid to be determined is determined to be an obstacle candidate. Note that if there is no grid in front of the grid to be determined, only the two grids on the left and right of the grid to be determined are used as comparison targets. Also, if there is no grid detected as a measured reference surface in the grid to be compared, the height data of the grid detected as the measured reference surface in front of that grid is recognized as the height data of the grid. Also, if there is no grid detected as a measured reference surface in all of the grids in front, the height data set as the virtual reference surface is set as the comparison target.

If the same obstacle candidate exists at a frequency equal to or higher than a predetermined set frequency (e.g. 3/5) in multiple (e.g. 5) grid maps created within a predetermined period, the obstacle The candidate is determined to be an obstacle, and the other obstacle candidates are determined not to be obstacles. If the obstacle determined in this manner exists within the above-mentioned obstacle detection area J, it is determined that the obstacle is detected and collision avoidance control is executed. Specifically, with reference to FIG. 12, if the closest obstacle to the tractor 1 is in the first obstacle detection area J1, the collision avoidance control detects that the obstacle exists in the area J1. will be notified. Furthermore, when the closest obstacle to the tractor 1 is located in the second obstacle detection area J2, the collision avoidance control notifies the tractor 1 of the presence of the obstacle in the area J2. vehicle speed is reduced. Furthermore, when the nearest obstacle to the tractor 1 is located in the third obstacle detection area J3, the collision avoidance control notifies the tractor 1 of the presence of the obstacle in the area J3. will be stopped.

Determination as to whether the obstacles are the same is performed as follows.
As shown in FIG. 22, when a plurality of grids determined as obstacles (shaded grids in FIG. 22) are arranged adjacently, the plurality of adjacent grids are the same obstacles O1, O2, It is determined that it is O3. Then, the centroid position (center of gravity) p of each obstacle O1, O2, O3 in plan view is determined, and the centroid position p is recognized as the position of each obstacle O1, O2, O3. . Note that the centroid position p can be determined by a conventional method, for example, by calculating the sum of the first moments of area at a predetermined origin of each grid that constitutes the obstacles O1, O2, O3, The centroid position p can be determined by utilizing the fact that the value obtained by dividing the sum of the first moments of area by the total cross-sectional area is the distance from the origin to the centroid position p.

Furthermore, in two successively generated grid maps, if the movement width of the centroid position p of an obstacle is referred to and the movement width is less than or equal to a predetermined setting movement width, these obstacles are considered to be the same. It is determined that it belongs to. For example, as shown in FIG. 23, the centroid position p (see FIG. 22) of the obstacle O is shown in the same grid in the continuously generated grid maps GM(-4) to GM(0). In this case, it is determined that these obstacles O are the same obstacle and that the obstacle is stationary. Furthermore, as shown in FIGS. 24 and 25, even if the centroid position p of the obstacle O is shown in different grids in two successively generated grid maps GM, each of the two grid maps GM If the movement width of the centroid position p of the obstacles O is less than or equal to the above-mentioned set movement width, those obstacles O are the same obstacle, and the obstacle is moving in the direction of movement of the centroid position p. It is determined that the object is moving along the

In addition, in FIGS. 23, 24, and 25, state examples of five grid maps GM(-4) to GM(0) created in a predetermined period up to the present time are shown, and these five grid maps GM(-4) to GM(0) show grids including an example of an obstacle O. Furthermore, grid map GM(0) is created at the current time, grid map GM(-1) is created one time before grid map GM(0), and grid map GM( -2) was created one time before grid map GM (-1), and grid map GM (-3) was created one time before grid map GM (-2). The grid map GM(-4) was created one time before the grid map GM(-3).

In the above-mentioned obstacle detection process, as shown in FIG. 25, in the previous grid maps GM(-4) to GM(-1) excluding the current one, there is an obstacle O within the obstacle detection area. However, the obstacle O may no longer exist in the current grid map GM(0). In such a case, there is a possibility that the obstacle O, which has been identified in the grid maps GM(-4) to GM(-1) up to this point, has moved into the blind spot where the measurement light does not reach. Therefore, in the obstacle detection process of this embodiment, a movement determination process for determining the movement state of the obstacle O is executed. The details of the movement determination process will be explained below along the process flow shown in FIG. 17.
Note that, referring to FIG. 12, the blind spot range is an area where the measurement light is blocked and cannot reach, such as the lower part of the hood, or an area closer to the tractor 1 than the third obstacle detection area J3, such as the area around the wheels. This range is outside the left and right distance measurement ranges C1 and D2, and therefore is a range where the measurement light does not reach.

In the movement determination process, the movement direction and movement speed of the obstacle O detected in the grid maps GM(-4) to GM(-1) up to the present time are referenced, and the position of the obstacle O in the grid map GM(0) at the present time is estimated (step #21 in FIG. 17). Then, using the estimated current position of the obstacle O, it is determined whether the obstacle O has moved into the blind spot range (step #22 in FIG. 17). Then, for example, as shown by the arrow T in FIG. 12, if it is determined that the obstacle O has moved into the blind spot range through the third obstacle detection area J3 (yes in step #22 in FIG. 17), the obstacle detection state is maintained (step #23 in FIG. 17). Then, the collision avoidance control for avoiding a collision with the obstacle O is continuously executed, the tractor 1 is maintained in a traveling stop state, and the collision of the tractor 1 with the obstacle O that has moved into the blind spot range is avoided.

Furthermore, if it is determined that the obstacle O has moved into the blind spot range (yes in step #22 in FIG. It is determined whether or not (step #24 in FIG. 17). Specifically, the determination of movement into the safe range can be made based on whether the estimated position of the obstacle O at the current moment has moved to the rear of the tractor 1. Further, for example, when the elapsed time from the time when the obstacle O moved into the blind spot range reaches a predetermined set time, it may be determined that the obstacle O has moved into the safe range. If it is determined that the obstacle O has moved within the safe range (step #24 in FIG. 17: yes), the obstacle detection state is canceled (step #25 in FIG. 17). Then, the collision avoidance control is stopped, and the tractor 1 resumes acceleration or running.

[Another embodiment]
Other embodiments of the present invention will be described. Note that the configurations of each embodiment described below are not limited to being applied individually, but can also be applied in combination with the configurations of other embodiments.

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

(2) In the above embodiment, the front rider sensor 101 and the rear rider sensor 102 are arranged at a position corresponding to the roof 35 in the vertical direction, but the arrangement position can be changed as appropriate. For example, the front rider sensor 101 can be placed at the front end of the bonnet 8, and the rear rider sensor 102 can be placed at a position corresponding to the roof 35. Further, the number of lidar sensors, the measurement range of each lidar sensor, etc. can be changed as appropriate.

(3) In the above embodiment, the obstacle detection unit 110 performs obstacle detection processing based on the measurement information of the lidar sensors 101 and 102, but the lidar sensors 101 and 102 may be equipped with a control unit. , the control unit can also perform obstacle detection processing. In this way, whether the obstacle detection process is performed on the sensor side or on the work vehicle side can be changed as appropriate.

(4) In the above embodiment, an example was shown in which the tractor 1 is provided with the obstacle detection section 110 and the collision avoidance control section 111. However, for example, it may be provided in a device other than the tractor 1, such as a mobile communication terminal 3. You can also do it.

1 Tractor (work vehicle)
100 Obstacle detection system 101, 102 Lidar sensor (distance measuring unit)
110 Obstacle detection unit (obstacle detection unit)
111 Collision avoidance control section (Collision avoidance control section)
J Obstacle detection area O Obstacle

Claims (3)

mounted on a work vehicle,
a distance measuring unit that irradiates the surrounding area with measurement light and receives reflected light of the measurement light to measure the distance to the distance measurement point from which the measurement light is reflected;
An obstacle detection system comprising: an obstacle detection unit that detects an obstacle within a predetermined obstacle detection area based on the measurement result of the distance measurement unit,
The obstacle detection section uses at least the distance of the intensity of the reflected light from the distance measurement point received by the distance measurement section and the distance to the distance measurement point measured by the distance measurement section, Determine whether the distance measurement point is a non-obstacle,
The obstacle detection unit determines that the distance measured by the distance measurement unit is within a range from a predetermined first set distance to a predetermined second set distance that is larger than the first set distance, and An obstacle that executes a floating object determination process that determines that the distance measurement point where the intensity of the reflected light received by the distance measurement unit is determined to be less than a predetermined setting intensity is a floating object as the non-obstruction. Object detection system. mounted on a work vehicle,
a distance measuring unit that irradiates the surrounding area with measurement light and receives reflected light of the measurement light to measure the distance to the distance measurement point from which the measurement light is reflected;
An obstacle detection system comprising: an obstacle detection unit that detects an obstacle within a predetermined obstacle detection area based on the measurement result of the distance measurement unit,
The obstacle detection section uses at least the distance of the intensity of the reflected light from the distance measurement point received by the distance measurement section and the distance to the distance measurement point measured by the distance measurement section, Determine whether the distance measurement point is a non-obstacle,
The obstacle detection unit is configured to detect a distance measured by the distance measurement unit when the distance measured by the distance measurement unit is within a range from a predetermined first set distance to a predetermined second set distance that is larger than the first set distance, and the distance measured by the distance measurement unit is Executing a floating object determination process that determines the ranging point where the intensity of the received reflected light is less than a predetermined setting intensity to be a floating object as the non-obstacle;
dirt in which the obstacle detection unit determines that the distance measurement point whose distance measured by the distance measurement unit is less than a predetermined first set distance is dirt on the distance measurement unit as a non-obstruction; An obstacle detection system that performs judgment processing. The obstacle detection section calculates a percentage of the ranging point determined to be dirty on the distance measuring section as a dirt percentage, and when the dirt percentage is equal to or higher than a predetermined dirt percentage, issues a predetermined dirt alarm. The obstacle detection system according to claim 2, wherein the obstacle detection system outputs an output.

Images