Work vehicles

Abstract

To provide a work vehicle capable of appropriately notifying a user of the presence of an obstacle according to an attitude of a work device.SOLUTION: A work vehicle estimates whether a vehicle body exists within a height limit application range registered in a map data based on a position of the vehicle body detected by a positioning sensor (S23). In response to the estimation that the vehicle body is within the height limit application range (S23: Yes), the height limit value associated with the height limit value application range and a vehicle height of the work vehicle calculated based on an attitude of a work device detected by an attitude sensor (S24). When the vehicle height is equal to or higher than the height limit value (S24: Yes), a notification device is activated (S25).SELECTED DRAWING: Figure 5

Description

[Technical Field]

[0001] The present invention relates to a work vehicle equipped with a work implement that moves in the vertical direction. [Background technology]

[0002] Conventionally, there have been known work vehicles equipped with a self-propelled vehicle body and a work implement supported on the vehicle body and moving in the vertical direction. Because the work implement of such work vehicles creates blind spots, there are known techniques for detecting surrounding obstacles with obstacle detection sensors and performing avoidance control for the detected obstacles (see, for example, Patent Documents 1 and 2).

[0003] The crane vehicle in Patent Document 1 sets a height limit value for the working equipment in advance and stops the working equipment at the set height.The forklift in Patent Document 2 sets a detection height according to the posture of the working equipment and brakes the vehicle body when it detects an obstacle below the detection height. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] Japanese Patent Application Laid-Open No. 2003-267666 [Patent Document 2] Japanese Patent Application Publication No. 2019-105995 Summary of the Invention [Problem to be solved by the invention]

[0005] However, in a work machine that travels while changing the height of the work implement, the technology of Patent Document 1 may perform excessive control to avoid obstacles, while the technology of Patent Document 2 may not detect obstacles sufficiently.

[0006] The present invention has been made in consideration of the above-described circumstances, and its object is to provide a work vehicle that can appropriately notify the driver of the presence of an obstacle depending on the attitude of the work implement. [Means for solving the problem]

[0007] In order to achieve the above object, the present invention provides a work vehicle comprising a self-propelled vehicle body, a working implement supported on the vehicle body and movable in the vertical direction, a positioning sensor that detects the position of the vehicle body, an attitude sensor that detects the attitude of the working implement, an alarm device that issues information, and a controller that controls the alarm device based on the detection results of the positioning sensor and the attitude sensor, the work vehicle comprising a memory that stores map data that associates a height limit value, which is the height at which the work vehicle can pass under an obstacle, with a height limit value application range, which is a range that includes the location of the obstacle, the memory stores a minimum height limit value that is the lowest height limit value within the travel range of the work vehicle; The controller calculates the vehicle height of the work vehicle based on the attitude of the work implement detected by the attitude sensor, and when the positioning error by the positioning sensor is less than a threshold value, activates the alarm device when the vehicle height is equal to or greater than the height limit value associated with the position of the vehicle body detected by the positioning sensor within the height limit value application range registered in the map data, and when the positioning error by the positioning sensor is equal to or greater than the threshold value, activates the alarm device when the vehicle height is equal to or greater than the height limit value associated with the position of the vehicle body detected by the positioning sensor within the height limit value application range registered in the map data, The minimum height limit When the above conditions are met, the alarm device is activated. [Effects of the Invention]

[0008] According to the present invention, it is possible to appropriately notify the user of the presence of an obstacle in accordance with the attitude of the working implement. Problems, configurations, and effects other than those described above will become apparent from the following description of the embodiments. [Brief explanation of the drawings]

[0009] [Figure 1] FIG. 1 is a side view of a wheel loader according to an embodiment of the present invention. [Figure 2] 1 is a block diagram of a wheel loader according to an embodiment of the present invention. [Figure 3] 4 is a flowchart of a map data generation process according to the present embodiment. [Figure 4] FIG. 2 is a schematic diagram showing height limit values ​​and height limit value application ranges included in map data. [Figure 5] 4 is a flowchart of an obstacle notification process according to the present embodiment. [Figure 6] FIG. 2 is a diagram showing a current location range. [Figure 7] FIG. 10 is a diagram showing a situation in which the alarm device is activated. [Figure 8] 10 is a flowchart of a map data generation process according to a first modification. [Figure 9] 10 is a flowchart of an obstacle notification process according to Modification 1. [Figure 10] FIG. 10 is a modified example of the block diagram of the wheel loader. [Figure 11] FIG. 2 is a schematic diagram showing a detection range and an exclusion range of a distance measurement sensor. DETAILED DESCRIPTION OF THE INVENTION

[0010] Below, a wheel loader 10, which is an example of a work vehicle according to the present invention, will be described with reference to the drawings. Note that, unless otherwise specified, front, rear, left, and right in this specification are based on the viewpoint of a worker who is riding on and operating the wheel loader 10. Furthermore, specific examples of work vehicles are not limited to the wheel loader 10, and may include dump trucks, hydraulic excavators, forklifts, and crane trucks.

[0011] FIG. 1 is a side view of a wheel loader 10 according to this embodiment. As shown in FIG. 1, the wheel loader 10 is made up of a front frame 11 and a rear frame 12. The front frame 11 and the rear frame 12 are connected by a center pin 13 so as to be rotatable in the left-right direction. The front frame 11 and the rear frame 12 are also connected by a pair of left and right steering cylinders (not shown). The pair of steering cylinders extend and retract when supplied with hydraulic oil from a hydraulic pump (not shown).

[0012] By extending one of the pair of steering cylinders and retracting the other, the front frame 11 bends left and right relative to the rear frame 12 around the center pin 13. This changes the relative mounting angle between the front frame 11 and the rear frame 12, causing the vehicle body to bend and change direction. In other words, this wheel loader 10 is an articulate type in which the front frame 11 and the rear frame 12 bend around the center pin 13.

[0013] The front frame 11 supports a pair of left and right front tires 15L, 15R and a front working mechanism 16. The front working mechanism 16 has a lift arm 17, a bucket 18, a pair of lift arm cylinders 19, a bucket cylinder 20, and a bell crank 21.

[0014] The lift arm 17 extends in the front-to-rear direction. More specifically, the front end of the lift arm 17 is rotatably connected to a bucket 18, and the rear end of the lift arm 17 is rotatably connected to the front frame 11. The lift arm 17 rotates in the up-and-down direction (moves up and down) by extension and contraction of a pair of lift arm cylinders 19.

[0015] The bucket 18 has a recessed space capable of accommodating cargo (such as earth and sand). The bucket 18 is supported at the front end of the lift arm 17 so as to be able to rotate (tilt or dump). More specifically, the bucket 18 rotates in the vertical direction as a bell crank 21 rotates in accordance with the extension and contraction of the bucket cylinder 20.

[0016] The rear frame 12 supports a pair of left and right rear tires 22L, 22R, and a cab 23 (operator's compartment). The cab 23 has an internal space where an operator who operates the wheel loader 10 sits. Inside the cab 23, there is a seat (not shown) on which the operator sits, and an operating device (not shown) that the operator operates while seated in the seat. When the operator sitting in the cab 23 operates the operating device, the wheel loader 10 travels and the front work implement 16 operates.

[0017] The front frame 11, the rear frame 12, the front tires 15L, 15R, the rear tires 22L, 22R, and the cab 23 are an example of a vehicle body. The front working implement 16 is an example of a working device that is supported by the vehicle body and moves in the vertical direction.

[0018] 2 is a block diagram of the wheel loader 10 according to this embodiment. As shown in FIG. 2, the wheel loader 10 mainly includes a distance measurement sensor 31, a position measurement sensor 32, an attitude sensor 33, an alarm device 34, and a controller 40.

[0019] The distance measurement sensor 31 is attached to the highest position of the vehicle body (for example, on the top surface of the cab 23 as shown in FIG. 1). The distance measurement sensor 31 detects the vertical height of an obstacle located above the vehicle body. The distance measurement sensor 31 then outputs a distance signal indicating the detected height to the controller 40. The detection range of the distance measurement sensor 31 is a cone-shaped range that widens upward, as shown in FIG. 4, for example. The distance measurement sensor 31 is, for example, a millimeter-wave radar, LiDAR, stereo camera, etc.

[0020] The positioning sensor 32 detects the position of the wheel loader 10. Then, the positioning sensor 32 outputs a position signal indicating the detected position to the controller 40. The positioning sensor 32 is, for example, a GPS (Global Positioning System) or a GNSS (Global Navigation Satellite System). The positioning sensor 32 includes, for example, an antenna attached to the top surface of the cab 23 to receive radio waves from a satellite, and a positioning controller that generates a position signal based on the radio waves received by the antenna.

[0021] The position signal includes, for example, position coordinates indicating the position of the wheel loader 10 and a positioning error (for example, the radius of a circle centered on the position coordinates) indicating the accuracy of the position coordinates. More specifically, the position coordinates are the coordinates of the installation position of the antenna of the positioning sensor 32 (hereinafter referred to as "positioning position coordinates"). In this specification, "xx coordinates" refers to an absolute position on the Earth (for example, latitude and longitude). On the other hand, "xx position" refers to a position inside the vehicle body.

[0022] The attitude sensor 33 detects the attitude of the front work implement 16. Then, the attitude sensor 33 outputs an attitude signal indicating the detected attitude to the controller 40. The attitude signal includes information for identifying the height from the ground to the tip of the bucket 18. The attitude sensor 33 includes, for example, an arm angle sensor that detects the angle of the lift arm 17 relative to the front frame 11, and a bucket angle sensor that detects the angle of the bucket 18 relative to the lift arm 17.

[0023] The notification device 34 is installed in the cab 23. The notification device 34 notifies information to the operator in the cab 23. The notification device 34 is, for example, a display, an LED lamp, a speaker, or a combination of these.

[0024] The controller 40 controls the overall operation of the wheel loader 10. The controller 40 has a CPU (Central Processing Unit) (not shown) and a memory 41. The memory 41 is configured, for example, from a ROM (Read Only Memory), a RAM (Random Access Memory), an HDD (Hard Disk Drive), or a combination of these.

[0025] However, the specific configuration of the controller 40 is not limited to this, and may be realized by hardware such as an ASIC (Application Specific Integrated Circuit) or an FPGA (Field-Programmable Gate Array).

[0026] The controller 40 realizes functional blocks of a map data generating unit 42, a vehicle body information calculating unit 43, and a notification processing unit 44 by having the CPU read and execute program codes stored in the memory 41. The memory 41 also stores map data 41a and vehicle body data 41b.

[0027] The map data generation unit 42 generates map data 41a based on the distance signal output from the distance measurement sensor 31, the position signal output from the positioning sensor 32, and the vehicle body data 41b stored in the memory 41. The vehicle body information calculation unit 43 calculates the current position range and vehicle height based on the position signal output from the positioning sensor 32 and the vehicle body data 41b stored in the memory 41. The notification processing unit 44 controls the notification device 34 based on the map data 41a stored in the memory 41 and the current position range and vehicle height calculated by the vehicle body information calculation unit 43.

[0028] The map data 41a is data that maps the positions and heights of obstacles detected in places where the wheel loader 10 has traveled in the past. The map data 41a has one or more sets of height limit values ​​and height limit value application ranges registered. The map data 41a is generated while the wheel loader 10 is traveling by a map data generation process, which will be described later.

[0029] The vehicle body data 41b is data that indicates the positions and dimensions of the components of the wheel loader 10. The vehicle body data 41b includes, for example, a "distance measurement height" that is the height from the ground to the installation position of the distance measurement sensor 31, a "distance measurement position" that is the installation position of the distance measurement sensor 31 in the horizontal direction, a "positioning position" that is the installation position of the antenna of the positioning sensor 32 in the horizontal direction, a "center position" of the wheel loader 10 in the horizontal direction, a "vehicle body radius" that is the radius of the smallest circle that includes the entire wheel loader 10 in the horizontal direction, a "vehicle body height" that is the height from the ground to the highest point of the vehicle body (for example, the top surface of the cab 23), and the dimensions of the lift arm 17 and bucket 18.

[0030] The processing of the map data generation unit 42 will be described with reference to Figures 3 and 4. Figure 3 is a flowchart of the map data generation processing according to this embodiment. Figure 4 is a schematic diagram showing the height limit values ​​and height limit value application ranges included in the map data 41a. The controller 40 repeatedly executes the map data generation processing shown in Figure 3 at predetermined time intervals while the wheel loader 10 is traveling.

[0031] First, the map data generation unit 42 determines whether or not an obstacle has been detected by the distance measurement sensor 31 (S11). The map data generation unit 42 outputs millimeter waves from the distance measurement sensor 31 and determines that an obstacle has been detected in response to receiving the reflected waves reflected by an obstacle. Then, in response to the fact that an obstacle has not been detected by the distance measurement sensor 31 (S11: No), the map data generation unit 42 ends the map data generation process without executing the processes from step S12 onwards.

[0032] Next, in response to the detection of an obstacle by the distance measurement sensor 31 (S11: Yes), the map data generation unit 42 calculates a height limit value (S12) based on the distance signal output from the distance measurement sensor 31. The height limit value is the height at which the wheel loader 10 can pass under the obstacle detected in step S11.

[0033] As shown in Fig. 4, the detected height indicated by the distance signal is the height from the installation position of the distance sensor 31 to the bottom of the obstacle. In other words, the obstacle height, which is the height from the ground to the bottom of the obstacle, is expressed as the sum of the detected height detected by the distance sensor 31 and the measured height registered in the vehicle body data 41b. The height limit value is set to a value less than the obstacle height. The map data generation unit 42 calculates the height limit value, for example, by multiplying the obstacle height by a coefficient α (<1).

[0034] Next, the map data generator 42 calculates the height limit value application range based on the position signal output from the positioning sensor 32 at the time when the distance measurement sensor 31 detects an obstacle (S13). The height limit value application range is a circular range on a horizontal plane centered on the coordinates of the installation position of the distance measurement sensor 31 (hereinafter referred to as "distance measurement position coordinates").

[0035] The map data generation unit 42 identifies the measured position coordinates based on, for example, the positioning position coordinates, the orientation of the front work implement 16 indicated by a compass mounted on the wheel loader 10, and the measured position and positioning position registered in the vehicle body data 41b. The map data generation unit 42 then calculates a circle having the measured position coordinates as its center and a radius indicated by the positioning error as the height limit value application range. The map data generation unit 42 may also calculate the height limit value application range by multiplying the radius indicated by the positioning error by a coefficient β (>1).

[0036] However, specific examples of the height limit value application range are not limited to the above examples. As another example, when the distance between the ranging position and the positioning position is small enough to be ignored, the map data generator 42 may calculate, as the height limit value application range, a circle whose center is the positioning position coordinates and whose radius is indicated by the positioning error.

[0037] Next, the map data generation unit 42 associates the height limit value calculated in step S12 with the height limit value application range calculated in step S13 and registers them in the map data 41a of the memory 41 (S14). That is, one or more sets of height limit values ​​and height limit value application ranges are registered in the map data 41a. Furthermore, as the travel distance of the wheel loader 10 increases, the number of sets of height limit values ​​and height limit value application ranges registered in the map data 41a increases.

[0038] The processing of the vehicle body information calculation unit 43 and the notification processing unit 44 will be described with reference to Figures 5 to 7. Figure 5 is a flowchart of the obstacle notification processing according to this embodiment. Figure 6 is a diagram showing the current position range. Figure 7 is a diagram showing a situation in which the notification device 34 operates. The controller 40 repeatedly executes the obstacle notification processing shown in Figure 5 at predetermined time intervals while the wheel loader 10 is traveling.

[0039] The vehicle body information calculation unit 43 calculates a current position range based on the position signal output from the positioning sensor 32 (S21). The current position range is a range in which the wheel loader 10 may be present. As shown in FIG. 6, the current position range is a circular range on a horizontal plane, centered on the coordinates of the central position of the wheel loader 10 (hereinafter referred to as "central position coordinates"). Note that if the distance between the measured position and the central position is small enough to be negligible, the circular range centered on the measured position may be used as the current position range.

[0040] The vehicle body information calculation unit 43 identifies the center position coordinates based on the measured position coordinates, the orientation of the front work implement 16 indicated by a compass mounted on the wheel loader 10, and the measured position and center position registered in the vehicle body data 41b. The vehicle body information calculation unit 43 then calculates a circle centered on the center position coordinates and having the larger of the vehicle body radius R0 and the radii R1 and R2 of the circle indicated by the positioning error as the current position range. In other words, the vehicle body information calculation unit 43 sets the circle with vehicle body radius R0 centered on the center position coordinates as the minimum current position range, and increases the current position range as the positioning error increases.

[0041] Next, the vehicle body information calculation unit 43 calculates the vehicle height of the wheel loader 10 based on the attitude signal output from the attitude sensor 33 and the vehicle body data 41b (S22). The vehicle height is the height from the ground to the highest point of the wheel loader 10 in the current attitude of the front work implement 16. The vehicle body information calculation unit 43 calculates the working implement height, which is the height from the ground to the tip of the bucket 18, based on the attitude signal output from the attitude sensor 33 and the dimensions of the lift arm 17 and bucket 18 registered in the vehicle body data 41b. The vehicle body information calculation unit 43 then calculates the vehicle height to be the higher of the calculated working implement height or the vehicle body height registered in the vehicle body data 41b.

[0042] Next, the notification processor 44 determines whether the current location range calculated in step S21 overlaps with a height limit value application range registered in the map data 41a (S23). Next, if the current location range overlaps with a height limit value application range (S23: Yes), the notification processor 44 compares the vehicle height calculated in step S22 with the height limit value associated with the height limit value application range that overlaps with the current location range (S24). Note that if the current location range overlaps with multiple height limit value application ranges, the notification processor 44 compares the vehicle height with the smallest height limit value among the height limit values ​​associated with each of the multiple height limit value application ranges.

[0043] Next, if the vehicle height is equal to or greater than the height limit value (S24: Yes), the notification processing unit 44 activates the notification device 34 (S25). As a result, the operator in the cab 23 is notified via the notification device 34 that there is a possibility that the wheel loader 10 will come into contact with an obstacle. The method of notification is not particularly limited, but examples include displaying a message on a display, turning on (or blinking) an LED, outputting a warning sound from a speaker, or a combination of these.

[0044] On the other hand, if the current position range does not overlap with the height limit range (S23: No), the notification processor 44 ends the obstacle notification process without executing the processes from step S24 onwards. Also, if the vehicle height is less than the height limit (S24: No), the notification processor 44 ends the obstacle notification process without executing the process of step S25.

[0045] According to the above embodiment, a warning is given that the wheel loader 10 may come into contact with an obstacle by comparing the map data 41a stored in advance in the memory 41 with the current position range and vehicle height calculated based on the detection results of the various sensors 32, 33. This makes it possible to issue warnings at appropriate times, suppressing both a decrease in work efficiency due to excessive warnings and contact with an obstacle due to insufficient warnings.

[0046] Furthermore, according to the above embodiment, whether or not the wheel loader 10 is present within the height limit value application range is estimated based on whether or not the current position range (plane) and the height limit value application range (plane) overlap. This makes it possible to prevent estimation errors due to positioning errors. However, in step S23, the notification processing unit 44 may also estimate that the wheel loader 10 is present within the height limit value application range based on the fact that the measured position coordinates (or measured position coordinates) are included within the height limit value application range.

[0047] Furthermore, according to the above embodiment, the larger the positioning error of the positioning sensor 32, the larger the current position range and height limit value application range can be, thereby more effectively preventing estimation errors. However, the current position range and height limit value application range may be ranges of a predetermined size (radius). Furthermore, the current position range and height limit value application range are not limited to a perfect circle shape. For example, the current position range may be set wider at the front side of the wheel loader 10 than at the rear side.

[0048] Incidentally, when the operator drives the wheel loader 10 in a place they are driving in for the first time, they will carefully check for the presence of obstacles, but when the operator drives in a place they have driven in many times, their attention is easily distracted. Therefore, as in the above embodiment, by executing the map data generation process shown in Figure 3 and the obstacle notification process shown in Figure 5 in parallel, map data 41a is generated the first time the vehicle passes near an obstacle, and a notification is issued the next time the vehicle passes near an obstacle. This makes it possible to prevent a decrease in the working efficiency of the wheel loader 10 and to provide notifications at appropriate times.

[0049] However, the map data generation process shown in Fig. 3 and the obstacle notification process shown in Fig. 5 do not have to be executed in parallel. As another example, the controller 40 may run the wheel loader 10 and execute the map data generation process shown in Fig. 3 before the wheel loader 10 performs actual work (such as transporting earth and sand). Then, after generating the map data 41a, the controller 40 may execute the obstacle notification process shown in Fig. 5 in parallel with the wheel loader 10 performing actual work.

[0050] Furthermore, the controller 40 does not have to execute the map data generation process shown in Fig. 3. As another example, the map data generation process shown in Fig. 3 may be executed by another vehicle. Then, the controller 40 may receive map data 41a generated by the other vehicle via a communication network, and execute the obstacle notification process shown in Fig. 5 using the received map data 41a.

[0051] [Variation 1] Next, the processing of the controller 40 according to Modification 1 will be described with reference to Fig. 8 and Fig. 9. Fig. 8 is a flowchart of map data generation processing according to Modification 1. Fig. 9 is a flowchart of obstacle notification processing according to Modification 1. Note that a detailed description of commonalities with the above embodiment will be omitted, and differences will be mainly described.

[0052] The map data generation process shown in Figure 8 differs from the map data generation process shown in Figure 3 in that steps S15 to S17 have been added. Moreover, the obstacle alarm process shown in Figure 9 differs from the obstacle alarm process shown in Figure 5 in that steps S26 to S27 have been added. Furthermore, a minimum height limit value is stored in the memory 41 according to the first modification. The minimum height limit value is the lowest height limit value within the travel range of the wheel loader 10.

[0053] 8, the map data generation unit 42 according to the first modification determines whether the positioning error of the positioning sensor 32 is equal to or greater than a threshold value between steps S12 and S13 (S15). If the positioning error is less than the threshold value (S15: No), the map data generation unit 42 executes the processes of step S13 and subsequent steps. On the other hand, if the positioning error is equal to or greater than the threshold value (S15: Yes), the map data generation unit 42 executes the processes of step S15 and subsequent steps without executing the processes of steps S13 to S14. In other words, the map data generation unit 42 does not register the height limit value and height limit value application range of an obstacle detected when the positioning error is equal to or greater than the threshold value in the map data 41a.

[0054] Next, the map data generation unit 42 compares the height limit value calculated in step S12 with the minimum height limit value stored in the memory 41 (S16). If the height limit value is less than the minimum height limit value (S16: Yes), the map data generation unit 42 overwrites the minimum height limit value stored in the memory 41 with the height limit value calculated in step S12 (S17). On the other hand, if the height limit value is equal to or greater than the minimum height limit value (S16: No), the map data generation unit 42 ends the map data generation process without executing the process of step S17. That is, the minimum height limit value is set to the smallest value of one or more height limit values ​​calculated in the repeatedly executed map data generation process.

[0055] 9, the notification processor 44 according to the first modification determines whether the positioning error of the positioning sensor 32 is equal to or greater than a threshold value between steps S22 and S23 (S26). If the positioning error is less than the threshold value (S26: No), the notification processor 44 executes the processes from step S23 onward. On the other hand, if the positioning error is equal to or greater than the threshold value (S26: Yes), the map data generator 42 compares the vehicle height calculated in step S22 with the minimum height limit value stored in the memory 41 instead of the processes of steps S23 and S24 (S27).

[0056] Next, if the vehicle height is equal to or greater than the minimum height limit (S27: Yes), the notification processor 44 executes the process of step S25. On the other hand, if the vehicle height is less than the minimum height limit (S27: No), the notification processor 44 does not execute the process of step S25 and ends the obstacle notification process. That is, if the positioning error is less than the threshold (S26: No), the notification processor 44 determines whether to issue a notification based on the map data 41a (S23 to S25). On the other hand, if the positioning error is equal to or greater than the threshold (S26: Yes), the notification processor 44 determines whether to issue a notification based on the minimum height limit (S27, S25).

[0057] According to Modification 1, if the positioning error of the positioning sensor 32 is equal to or greater than a threshold value, the current position range is determined to be unreliable and the minimum height limit value is compared with the vehicle height. This makes it possible to appropriately notify the driver of the possibility that the wheel loader 10 will come into contact with an obstacle, even in places with poor radio wave environments such as mountainous regions or indoors.

[0058] [Other variations] Next, other modified examples will be described with reference to Figures 10 and 11. Figure 10 is a modified example of a block diagram of the wheel loader 10. Figure 11 is a schematic diagram showing the detection range and exclusion range of the distance measurement sensor 31. Note that a detailed description of the commonalities with the above embodiment and modified example 1 will be omitted, and the description will focus on the differences.

[0059] As shown in Fig. 10, the wheel loader 10 may further include an operation device 35. The operation device 35 accepts input operations by an operator. The operation device 35 is, for example, a touch panel superimposed on a display, a push button, a lever, a switch, or a combination of these. The controller 40 may then accept an input operation for specifying an exclusion range through the operation device 35.

[0060] 11, the exclusion range is a portion of the detection range of the distance measurement sensor 31. The exclusion range is a range within the detection range of the distance measurement sensor 31 in which an object detected in step S11 in FIGS. 3 and 8 is not considered to be an obstacle. That is, if an obstacle is detected by the distance measurement sensor 31 in a range different from the exclusion range in step S11 in FIGS. 3 and 8, the controller 40 may execute the processes from step S12 onward.

[0061] 11, for example, there is a possibility that the front working implement 16 may enter the front side of the detection range of the distance measurement sensor 31. As a result, there is a possibility that the front working implement 16 may be mistaken for an obstacle, and an inappropriate height limit value and height limit value application range may be registered in the map data 41a. Therefore, by specifying such a range as an exclusion range, the presence of an obstacle can be more appropriately notified.

[0062] 10, the controller 40 may further include a map data deletion unit 45. The map data deletion unit 45 may delete the map data 41a from the memory 41 in response to receiving an input operation instructing deletion of the map data 41a via the operation device 35. The map data deletion unit 45 can delete the entire map data 41a, as well as some of the height limit values ​​and height limit value application ranges registered in the map data 41a, and some of the map data 41a.

[0063] As a result, even if the obstacle at the work site is subsequently removed or the wheel loader 10 is moved to another work site, the presence of the obstacle can be appropriately reported.

[0064] The above-described embodiments are merely illustrative examples of the present invention, and are not intended to limit the scope of the present invention to these embodiments. Those skilled in the art can implement the present invention in various other forms without departing from the spirit of the present invention. [Explanation of symbols]

[0065] 10 Wheel loader (work vehicle) 11 Front frame (body) 12 Rear frame (body) 13 Center pin 15L, 15R front tires 16 Front work equipment (working equipment) 17 Lift arm 18 Buckets 19 Lift arm cylinder 20 Bucket Cylinder 21 Bell crank 22L, 22R rear tires 23 Cab 31 Distance sensor 32 Positioning sensor 33 Attitude Sensor 34 Alarm device 35 Operating device 40 Controller 41 memory 41a Map Data 41b Body Data 42 Map data generation unit 43 Vehicle information calculation unit 44 Notification processing section 45 Map data deletion section

Claims

1. A self-propelled vehicle, a working device supported on the vehicle body and movable in a vertical direction; a positioning sensor that detects the position of the vehicle body; an attitude sensor that detects the attitude of the working device; an alarm device that notifies information; a controller that controls the notification device based on detection results of the positioning sensor and the attitude sensor; In a work vehicle equipped with a memory for storing map data in which a height limit value, which is a height at which the work vehicle can pass under an obstacle, is associated with a height limit value application range, which is a range including the position where the obstacle is present; The memory includes: a minimum height limit value that is the lowest height limit value within the travel range of the work vehicle is stored; The controller Calculating the vehicle height of the work vehicle based on the attitude of the work implement detected by the attitude sensor; If the positioning error by the positioning sensor is less than a threshold value, when the vehicle height is equal to or greater than the height limit value associated with the position of the vehicle body detected by the positioning sensor within the height limit value application range registered in the map data, the notification device is activated; When the positioning error by the positioning sensor is equal to or greater than a threshold value, the alarm device is activated when the vehicle height is equal to or greater than the minimum height limit value, regardless of the magnitude of the height limit value associated with the position where the vehicle body detected by the positioning sensor is located within the height limit value application range registered in the map data. A work vehicle characterized by:

2. The work vehicle according to claim 1, The controller When a current position range including the position of the vehicle detected by the positioning sensor overlaps with the height limit value application range registered in the map data, it is estimated that the vehicle is present within the height limit value application range. A work vehicle characterized by:

3. The work vehicle according to claim 2, The controller The larger the positioning error by the positioning sensor, the larger the current position range is set. A work vehicle characterized by:

4. A self-propelled vehicle body; a working device supported on the vehicle body and movable in a vertical direction; a positioning sensor that detects the position of the vehicle body; an attitude sensor that detects the attitude of the working device; an alarm device that notifies information; a controller that controls the notification device based on detection results of the positioning sensor and the attitude sensor; In a work vehicle equipped with a memory for storing map data in which a height limit value, which is a height at which the work vehicle can pass under an obstacle, is associated with a height limit value application range, which is a range that includes the location of the obstacle; and a distance measuring sensor that detects a vertical distance to an obstacle located above the vehicle body; Equipped with The controller calculating the height limit value based on the vertical distance of the obstacle detected by the distance measuring sensor; calculating the height limit value application range based on the position of the vehicle body detected by the positioning sensor at the time when the obstacle is detected by the distance measuring sensor; The calculated height limit value and the height limit value application range are associated with each other and registered in the map data; When the position of the vehicle body detected by the positioning sensor is within the height limit value application range registered in the map data, the notification device is activated when the vehicle height of the work vehicle calculated based on the attitude of the work implement detected by the attitude sensor is equal to or greater than the height limit value associated with the position of the vehicle body detected by the attitude sensor within the height limit value application range. A work vehicle characterized by:

5. The work vehicle according to claim 4, The controller The larger the positioning error by the positioning sensor, the larger the range of application of the height limit value. A work vehicle characterized by:

6. The work vehicle according to claim 4, An operation device for receiving an input operation is provided, The controller receiving, via the operation device, an input operation for specifying an exclusion range within the detection range of the distance measuring sensor, within which a detected object is not regarded as an obstacle; The height limit value is calculated based on the vertical distance of an obstacle detected by the distance measuring sensor in a range different from the exclusion range. A work vehicle characterized by:

7. The work vehicle according to claim 1, An operation device for receiving an input operation is provided, The controller The map data is deleted from the memory in response to receiving an input operation for instructing deletion of the map data through the operation device. A work vehicle characterized by:

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