Industrial vehicle

Abstract

An industrial vehicle suppresses a divergence between a travel direction of the industrial vehicle recognized by a control device and an actual travel direction of the industrial vehicle. The fork truck is provided with a vehicle speed detection sensor, a direction lever, an object detection section, and a control device. The direction lever determines the travel direction. The object detection section detects a position of an object present in the travel direction of the fork truck. The control device becomes a specified state when the speed of the fork truck is above a first vehicle speed threshold. The specified state is a state in which, even if a travel direction instruction given by the direction lever changes, the control device recognizes that a state before the change is still continuing, and the object detection section functions based on the state before the change.

Description

Technical Field

[0001] This disclosure relates to industrial vehicles. Background Technology

[0002] The industrial vehicle disclosed in Patent Document 1 includes a control device, a direction sensor, and a steering lever. The control device controls the industrial vehicle. The direction sensor detects the direction of operation of the steering lever, which determines the direction of travel. The direction sensor detects, based on a neutral position, whether the steering lever was operated in the direction indicating forward movement or in the direction indicating reverse movement. The control device switches the travel mode based on the steering lever operation. The travel modes include a forward mode and a reverse mode. When the steering lever is in the forward position, the control device sets the industrial vehicle to forward mode. When the steering lever is in the reverse position, the control device sets the industrial vehicle to reverse mode. When the speed of the industrial vehicle is above a predetermined speed, the control device maintains the travel mode even if the direction of travel indicated by the steering lever is changed. In this case, the direction of travel indicated by the steering lever is opposite to the direction of travel of the industrial vehicle.

[0003] Existing technical documents

[0004] Patent documents

[0005] Patent Document 1: Japanese Patent Application Publication No. 2006-322413 Summary of the Invention

[0006] The problem the invention aims to solve

[0007] Industrial vehicles sometimes have object detection units. These units detect the position of objects present in the vehicle's direction of travel. When the control unit identifies the direction of travel indicated by the steering lever as the vehicle's actual direction of travel, during the period between the point where the steering lever position is switched and the vehicle's actual direction of travel is switched, the direction of travel identified by the control unit may be opposite to the vehicle's actual direction of travel. In this situation, the control unit may sometimes fail to detect objects present in the vehicle's actual direction of travel.

[0008] Solution for solving the problem

[0009] An industrial vehicle that solves the above problems includes: a travel direction detection unit that detects the travel direction of the industrial vehicle; a vehicle speed detection sensor that detects the speed of the industrial vehicle; a travel direction determination unit that determines the travel direction of the industrial vehicle; an object detection unit that detects the position of an object existing in the travel direction of the industrial vehicle; and a control device that enters a specific state when the speed of the industrial vehicle detected by the vehicle speed detection sensor is above a first vehicle speed threshold. The specific state is such that even if the travel direction command given by the travel direction determination unit changes, the control device recognizes that the state before the change is still continuing, and the object detection unit functions based on the state before the change.

[0010] When the direction of travel command given by the direction of travel determination unit changes during the movement of the industrial vehicle, the direction of travel of the industrial vehicle is switched after the speed of the industrial vehicle decreases. When the direction of travel command given by the direction of travel determination unit changes while the speed of the industrial vehicle is above the first speed threshold, the direction of travel of the industrial vehicle is maintained at least until the speed of the industrial vehicle falls below the first speed threshold. When the speed of the industrial vehicle is above the first speed threshold, the control device enters a specific state. In the specific state, even if the direction of travel command given by the direction of travel determination unit changes, the control device recognizes that the state before the change is still continuing. As a result, it is possible to suppress the deviation between the direction of travel of the industrial vehicle recognized by the control device and the actual direction of travel of the industrial vehicle. Furthermore, even if the direction of travel command given by the direction of travel determination unit changes, the object detection unit functions based on the state before the change, thereby enabling the detection of objects in accordance with the direction of travel of the industrial vehicle.

[0011] The aforementioned industrial vehicle may also include a notification unit that notifies the industrial vehicle when the object detected by the object detection unit is likely to come into contact with it. The control device determines, in the specific state, whether the object is likely to come into contact with the industrial vehicle based on the state before the change.

[0012] The aforementioned industrial vehicle may also include: an engine; and a power transmission mechanism, the power transmission mechanism being able to switch between a drive transmission state in which the driving force of the engine is transmitted to the power transmission mechanism, and a drive non-transmission state in which the driving force of the engine is not transmitted to the power transmission mechanism, wherein the control device sets the power transmission mechanism to the drive non-transmission state in the specific state.

[0013] The aforementioned industrial vehicle may also include an interlocking device that sets the power transmission mechanism to the drive-off state. When the speed of the industrial vehicle is greater than or equal to a second speed threshold that is greater than a first speed threshold, and the travel direction command given by the travel direction determination unit changes, the control device sets the power transmission mechanism to the drive-off state through the interlocking device, and the first speed threshold is set to be lower than the second speed threshold.

[0014] Invention Effects

[0015] According to the present invention, it is possible to suppress the deviation between the direction of travel of the industrial vehicle identified by the control device and the actual direction of travel of the industrial vehicle. Attached Figure Description

[0016] Figure 1 It's a 3D model of a forklift.

[0017] Figure 2 This is a schematic diagram of the forklift's components.

[0018] Figure 3 This is a schematic diagram of the driving system.

[0019] Figure 4 This is a flowchart illustrating the object detection process.

[0020] Figure 5 It is a schematic diagram showing the expected trajectory.

[0021] Figure 6 It is a schematic diagram showing the expected trajectory.

[0022] Figure 7 It is a schematic diagram showing the expected trajectory.

[0023] Figure 8 It is a schematic diagram showing the expected trajectory.

[0024] Figure 9 This is a flowchart illustrating the notification control.

[0025] Figure 10 This is a schematic diagram used to illustrate the function of the implementation method.

[0026] Figure 11 This is a schematic diagram used to illustrate the function of the implementation method.

[0027] Figure 12 This is a schematic diagram of the modified forklift.

[0028] Explanation of reference numerals in the attached figures

[0029] 10…forklift as an industrial vehicle, 31…engine, 40…power transmission mechanism, 81…control device, 89…direction lever as direction determination unit, 90…direction switch as direction detection unit, 110…interlocking device, 131…object detection unit, 136…notification unit. Detailed Implementation

[0030] The following describes one embodiment of the industrial vehicle.

[0031] <Forklift>

[0032] like Figure 1 As shown, the forklift 10, as an industrial vehicle, includes a body 11, two drive wheels 12, two steering wheels 14, and a cargo loading and unloading device 20. In the following description, front, back, left, and right refer to the front, back, left, and right of the forklift 10.

[0033] The vehicle body 11 has a roof guard 15 located above the driver's seat. Two drive wheels 12 are located at the front of the vehicle body 11. The two drive wheels 12 are spaced apart in the vehicle width direction. Two steering wheels 14 are located at the rear of the vehicle body 11. The two steering wheels 14 are spaced apart in the vehicle width direction.

[0034] The cargo loading and unloading device 20 includes a mast 21, two forks 22, and a lifting cylinder 23. The mast 21 is located at the front of the vehicle body 11. The forks 22 are configured to rise and fall together with the mast 21. Goods are loaded onto the forks 22. The lifting cylinder 23 is a hydraulic cylinder. The mast 21 rises and falls by extending and retracting the lifting cylinder 23. The forks 22 rise and fall along with the rise and fall of the mast 21. The forklift 10 of this embodiment is a forklift that performs driving and cargo loading and unloading operations through the operation of a rider.

[0035] <Components of a Forklift>

[0036] like Figure 2 As shown, the forklift 10 includes: a driving system 30, a control device 81, an accelerator pedal 86, an acceleration sensor 87, a tire angle sensor 88, a steering rod 89, a steering switch 90, a forward connection line 101, a reverse connection line 102, a forward detection line 103, a reverse detection line 104, an interlock device 110, and an object detection unit 131.

[0037] <Driving System>

[0038] like Figure 3 As shown, the travel system 30 is a mechanism for moving the forklift 10. The travel system 30 includes: an engine 31, an output shaft 33, a speed sensor 34, a power transmission mechanism 40, a solenoid valve 50, a forward solenoid 51, a reverse solenoid 52, a differential device 60, an axle 61, a vehicle speed detection sensor 62, and a travel control device 63.

[0039] Engine 31 is the drive source for the forklift 10's driving and loading / unloading operations. In this embodiment, engine 31 is a gasoline engine that uses gasoline as fuel. Engine 31 includes a throttle actuator 32. The throttle actuator 32 adjusts the throttle opening of a throttle valve (not shown) located in the intake path to follow the target engine speed calculated based on the opening of the accelerator pedal 86. By adjusting the throttle opening using the throttle actuator 32, the amount of air supplied to engine 31 can be adjusted. This allows control of the engine speed. Alternatively, a diesel engine using light oil as fuel can be used as engine 31. An engine using liquefied petroleum gas or compressed natural gas can also be used as engine 31. Output shaft 33 is connected to engine 31. Output shaft 33 rotates under the drive of engine 31.

[0040] A speed sensor 34 is located on the output shaft 33. The speed sensor 34 detects the speed of the engine 31. The speed of the engine 31 refers to the speed of the output shaft 33. The speed sensor 34 outputs an electrical signal corresponding to the speed of the output shaft 33 to the driving control device 63.

[0041] The power transmission mechanism 40 transmits the driving force of the engine 31 to the drive wheels 12. The power transmission mechanism 40 includes a torque converter 41 and a transmission 42.

[0042] Torque converter 41 is connected to output shaft 33. The driving force of engine 31 is transmitted to torque converter 41 via output shaft 33. Torque converter 41 includes a pump connected to output shaft 33 and a turbine. In torque converter 41, turbine rotates by working oil injected from pump.

[0043] The transmission 42 includes an input shaft 43, a forward clutch 44, a forward gear train 45, a reverse clutch 46, a reverse gear train 47, and an output shaft 48. The input shaft 43 is connected to the torque converter 41. Driving force is transmitted from the torque converter 41 to the transmission 42 via the input shaft 43.

[0044] A forward clutch 44 is disposed on the input shaft 43. A forward gear train 45 is disposed between the forward clutch 44 and the output shaft 48. The forward clutch 44 switches between an engaged state and a disengaged state. The engaged state is when the input shaft 43 and the forward gear train 45 are connected. The disengaged state is when the input shaft 43 and the forward gear train 45 are disconnected. When the input shaft 43 and the forward gear train 45 are connected via the forward clutch 44, driving force is transmitted from the input shaft 43 to the forward gear train 45. The driving force transmitted to the forward gear train 45 is then transmitted to the output shaft 48. In other words, when the forward clutch 44 is engaged with the forward gear train 45, the driving force of the engine 31 is transmitted to the output shaft 48. When the forward clutch 44 is disengaged from the forward gear train 45, driving force is not transmitted from the input shaft 43 to the forward gear train 45. A hydraulic clutch is used as the forward clutch 44. For example, a wet multi-plate clutch can be cited as a hydraulic clutch.

[0045] A reverse clutch 46 is disposed on the input shaft 43. A reverse gear train 47 is disposed between the reverse clutch 46 and the output shaft 48. The reverse clutch 46 switches between an engaged state and a disengaged state. The engaged state is when the input shaft 43 and the reverse gear train 47 are connected. The disengaged state is when the input shaft 43 and the reverse gear train 47 are disconnected. When the input shaft 43 and the reverse gear train 47 are engaged via the reverse clutch 46, driving force is transmitted from the input shaft 43 to the reverse gear train 47. The driving force transmitted to the reverse gear train 47 is then transmitted to the output shaft 48. In other words, when the reverse clutch 46 is engaged with the reverse gear train 47, the driving force of the engine 31 is transmitted to the output shaft 48. When the reverse clutch 46 is disengaged from the reverse gear train 47, driving force is not transmitted from the input shaft 43 to the reverse gear train 47. A hydraulic clutch is used as the reverse clutch 46. Examples of hydraulic clutches include, for example, a wet multi-plate clutch.

[0046] Solenoid valve 50 controls the supply of working oil to the forward clutch 44 and the reverse clutch 46, as well as the discharge of working oil from the forward clutch 44 and the reverse clutch 46. By supplying and discharging working oil through solenoid valve 50, the engagement and disengagement states of clutches 44 and 46 can be switched.

[0047] Solenoids 51 and 52 switch solenoid valve 50 to supply and discharge working oil to clutches 44 and 46. When the forward solenoid 51 is energized, working oil is supplied from solenoid valve 50 to the forward clutch 44. With working oil supplied to the forward clutch 44, the forward clutch 44 is engaged. When the reverse solenoid 52 is energized, working oil is supplied from solenoid valve 50 to the reverse clutch 46. With working oil supplied to the reverse clutch 46, the reverse clutch 46 is engaged.

[0048] As solenoid valve 50, a single solenoid directional switching valve can be used. This solenoid directional switching valve is a solenoid valve that, when the forward solenoid 51 is energized, switches to a position supplying working oil 4 to the forward clutch 44, and when the reverse solenoid 52 is energized, switches to a position supplying working oil to the reverse clutch 46. When both the forward and reverse solenoids 51 and 52 are demagnetized, the solenoid directional switching valve switches to a position discharging working oil from both clutches 44 and 46. Furthermore, the working oil that operates the forward clutch 44 and the reverse clutch 46 is supplied by a hydraulic pump located inside the power transmission mechanism 40. The configuration of this hydraulic pump is known.

[0049] Two solenoid valves can also be used as solenoid valve 50. Each of the two solenoid valves is respectively set to correspond to the forward clutch 44 and the reverse clutch 46. In this case, the supply of working oil to the two clutches 44 and 46 and the discharge of working oil from the two clutches 44 and 46 can be achieved by individually controlling each solenoid valve 50 through the forward solenoid 51 and the reverse solenoid 52.

[0050] The power transmission mechanism 40 can be switched between a drive transmission state, in which the driving force of the engine 31 is transmitted to the power transmission mechanism 40, and a drive non-transmission state, in which the driving force of the engine 31 is not transmitted to the power transmission mechanism 40. When either the forward clutch 44 or the reverse clutch 46 is engaged, the driving force of the engine 31 is transmitted to the power transmission mechanism 40, thereby causing the forklift 10 to move. The engagement of either the forward clutch 44 or the reverse clutch 46 constitutes the drive transmission state. When both the forward clutch 44 and the reverse clutch 46 are disengaged, the driving force of the engine 31 is not transmitted to the power transmission mechanism 40. The disengagement of both the forward clutch 44 and the reverse clutch 46 constitutes the drive non-transmission state.

[0051] Differential 60 is connected to output shaft 48. Axle 61 is connected to differential 60. Axle 61 is connected to drive wheel 12. Rotation of output shaft 48 causes axle 61 to rotate. Rotation of axle 61 causes drive wheel 12 to rotate, thereby moving forklift 10. If forward clutch 44 is engaged with forward gear train 45, forklift 10 moves forward. If reverse clutch 46 is engaged with reverse gear train 47, forklift 10 moves backward.

[0052] The vehicle speed detection sensor 62 is a sensor used to detect the speed of the forklift 10. The vehicle speed detection sensor 62 is, for example, installed on the output shaft 48 or the axle 61. The vehicle speed detection sensor 62 outputs a pulse signal corresponding to the speed of the forklift 10 to the driving control device 63.

[0053] The driving control device 63 is an engine control unit that controls the engine 31. The driving control device 63 adjusts the throttle opening by controlling the throttle actuator 32. By adjusting the throttle opening, the driving force of the engine 31 can be adjusted.

[0054] <Control Device>

[0055] like Figure 2 As shown, the control device 81 includes a processor 82 and a storage unit 83. The processor 82 can be, for example, a CPU (Central Processing Unit), a GPU (Graphics Processing Unit), or a DSP (Digital Signal Processor). The storage unit 83 includes RAM (Random Access Memory) and ROM (Read Only Memory). The storage unit 83 stores program code or instructions configured to cause the processor 82 to perform processing. The storage unit 83, i.e., the computer-readable medium, includes all usable media accessible by a general-purpose or special-purpose computer. The control device 81 may also be constructed from hardware circuits such as ASICs (Application Specific Integrated Circuits) or FPGAs (Field Programmable Gate Arrays). The control device 81, as a processing circuit, can include one or more processors, ASICs, or FPGAs, or combinations thereof, that operate according to a computer program.

[0056] <Acceleration sensor and tire angle sensor>

[0057] Acceleration sensor 87 detects the amount of operation of accelerator pedal 86. The amount of operation of accelerator pedal 86 can also be referred to as the accelerator opening. Acceleration sensor 87 outputs an electrical signal corresponding to the accelerator opening to control device 81. Control device 81 can identify the accelerator opening through the electrical signal from acceleration sensor 87.

[0058] The tire angle sensor 88 detects the steering angle of the steering wheel 14. The tire angle sensor 88 outputs an electrical signal corresponding to the steering angle to the control device 81. The control device 81 can identify the steering angle through the electrical signal from the tire angle sensor 88.

[0059] <Direction stick>

[0060] The direction lever 89 determines the travel direction of the forklift 10. The direction lever 89 is operated by the rider of the forklift 10. The direction lever 89 is operated from a neutral position to either a forward position (indicating forward movement) or a reverse position (indicating reverse movement). For example, the forward position is when the direction lever 89 is tilted forward from the neutral position. The reverse position is when the direction lever 89 is tilted backward from the neutral position. The direction lever 89 is the travel direction determining unit. By operating the direction lever 89, the rider can give travel direction commands to the forklift 10. Travel direction commands are commands that instruct the forklift 10 to travel in the correct direction. Travel direction commands include forward commands and reverse commands. A forward command instructs the forklift 10 to move forward. A reverse command instructs the forklift 10 to move backward.

[0061] <Direction Switch>

[0062] The direction switch 90 switches according to the operating direction of the steering lever 89. The direction switch 90 has one movable contact 91 and three fixed contacts 92, 93, and 94. The movable contact 91 is connected to the positive terminal of the battery mounted on the forklift 10. The three fixed contacts 92, 93, and 94 include a neutral fixed contact 92, a forward fixed contact 93, and a reverse fixed contact 94. When the steering lever 89 is in the neutral position, the movable contact 91 is connected to the neutral fixed contact 92. When the steering lever 89 is in the forward position, the movable contact 91 is connected to the forward fixed contact 93. When the steering lever 89 is in the reverse position, the movable contact 91 is connected to the reverse fixed contact 94. The direction switch 90 is a travel direction detection unit. Alternatively, the direction switch 90 can consist of three buttons, including forward, neutral, and reverse positions, configured such that the contacts are connected when each button is operated.

[0063] <Forward connector and backward connector>

[0064] The forward connecting line 101 connects the forward fixed contact 93 to the forward solenoid 51. When the movable contact 91 and the forward fixed contact 93 are connected, the forward connecting line 101 is electrically connected to the battery. As a result, the forward solenoid 51 is energized. When the movable contact 91 and the forward fixed contact 93 are connected, the retracting solenoid 52 is demagnetized.

[0065] The reversing connecting line 102 connects the reversing fixed contact 94 to the reversing solenoid 52. When the movable contact 91 is connected to the reversing fixed contact 94, the reversing connecting line 102 is electrically connected to the battery. This energizes the reversing solenoid 52. When the movable contact 91 is connected to the reversing fixed contact 94, the forward solenoid 52 is demagnetized.

[0066] When the steering lever 89 is in the forward position, the forward solenoid 51 is energized, supplying hydraulic fluid to the forward clutch 44. This allows the forklift 10 to move forward. When the steering lever 89 is in the reverse position, the reverse solenoid 52 is energized, supplying hydraulic fluid to the reverse clutch 46. This allows the forklift 10 to move backward. When the steering lever 89 is in the neutral position, the two solenoids 51 and 52 are demagnetized, preventing the supply of hydraulic fluid to clutches 44 and 46. In this case, the driving force of the engine 31 is not transmitted to the power transmission mechanism 40.

[0067] <Forward and Backward Detection Lines>

[0068] The forward detection line 103 connects the forward connection line 101 to the control device 81. When a voltage from the battery is applied to the forward connection line 101, the voltage is applied to the control device 81 via the forward detection line 103. The reverse detection line 104 connects the reverse connection line 102 to the control device 81. When a voltage from the battery is applied to the reverse connection line 102, the voltage is applied to the control device 81 via the reverse detection line 104. When voltage is input from the forward detection line 103, the control device 81 can determine that the steering stick 89 is in the forward position. When voltage is input from the reverse detection line 104, the control device 81 can determine that the steering stick 89 is in the reverse position. Specifically, the control device 81 has a port 84 connected to the forward detection line 103 and a port 85 connected to the reverse detection line 104. If voltage is applied to port 84, the control device 81 can determine that the steering stick 89 is in the forward position. If voltage is applied to port 85, control device 81 can determine that the directional stick 89 is in the reverse position. If there is no voltage input to either the forward detection line 103 or the reverse detection line 104, control device 81 can determine that the directional stick 89 is in the neutral position. If the directional stick 89 is in the forward position, control device 81 determines that a forward command has been input. If the directional stick 89 is in the reverse position, control device 81 determines that a reverse command has been input.

[0069] <Interlocking Device>

[0070] The interlocking device 110 includes a forward relay 111 and a reverse relay 112. The forward relay 111 is located on the forward connecting line 101. The forward relay 111 switches between a connected state and a disconnected state. When the forward relay 111 is in the connected state, the forward connecting line 101 is electrically connected to the forward solenoid 51. When the forward relay 111 is in the disconnected state, the forward connecting line 101 and the forward solenoid 51 are electrically disconnected. The reverse relay 112 is located on the reverse connecting line 102. The reverse relay 112 switches between a connected state and a disconnected state. When the reverse relay 112 is in the connected state, the reverse connecting line 102 is electrically connected to the reverse solenoid 52. When the reverse relay 112 is in the disconnected state, the reverse connecting line 102 and the reverse solenoid 52 are electrically disconnected.

[0071] <Object Detection Department>

[0072] The object detection unit 131 includes a stereo camera 132, a detection device 133, and a notification unit 136. The stereo camera 132 has two cameras, and images are taken by both cameras. Figure 1 As shown, a stereo camera 132 is disposed on the overhead guard 15. The stereo camera 132 is configured to view the road surface on which the forklift 10 travels from above the forklift 10. In this embodiment, the stereo camera 132 captures images of the rear of the forklift 10. Therefore, the object detected by the object detection unit 131 is an object behind the forklift 10. The detection direction of the object detection unit 131 can be considered rearward. The notification unit 136 and the detection device 133 can be unitized with the stereo camera 132 and disposed together with the stereo camera 132 on the overhead guard 15. Alternatively, the notification unit 136 and the detection device 133 can also be disposed at a different position than the overhead guard 15.

[0073] The detection device 133 includes a processor 134 and a storage unit 135. The processor 134 may be, for example, a CPU, GPU, or DSP. The storage unit 135 includes RAM and ROM. The storage unit 135 stores various programs for detecting objects based on images captured by the stereo camera 132. In essence, the storage unit 135 stores program code or instructions configured to cause the processor 134 to perform processing. The storage unit 135, i.e., the computer-readable medium, includes all available media accessible by a general-purpose or special-purpose computer. The detection device 133 may also be constructed from hardware circuits such as ASICs or FPGAs. The detection device 133, as a processing circuit, can include one or more processors, ASICs, or FPGAs, or combinations thereof, that operate according to a computer program.

[0074] <Object Detection and Processing>

[0075] The detection device 133 detects objects located behind the forklift 10 by repeatedly performing the following object detection process according to a predetermined control cycle. Furthermore, the detection device 133 outputs the position of the detected object. The object's position refers to the relative position between the forklift 10 and the object.

[0076] like Figure 4 As shown, in step S100, the detection device 133 acquires an image from the stereo camera 132.

[0077] Next, in step S110, the detection device 133 obtains a disparity image by performing stereo processing. A disparity image is an image that maps disparity [px] to pixels. The disparity image is not necessarily an image that needs to be displayed; rather, it represents data showing how each pixel in the disparity image is mapped to its corresponding disparity. Disparity can be obtained by comparing two images captured by the stereo camera 132 and deriving the difference in the number of pixels between the images for the same feature point presented in each image. Feature points refer to identifiable boundaries, such as the edges of an object. Feature points can be detected based on information such as brightness.

[0078] Next, in step S120, the detection device 133 derives the coordinates of feature points in the world coordinate system, which serves as the coordinate system in actual space. The world coordinate system is a coordinate system with the forklift 10 positioned horizontally, using an axis extending horizontally in the width direction of the forklift 10 as the X-axis, an axis orthogonal to the X-axis in the horizontal direction as the Y-axis, and an axis extending vertically as the Z-axis. The coordinates of the feature points are derived as follows: based on the baseline length of the stereo camera 132, the focal length of the stereo camera 132, and the parallax image obtained in step S110, the coordinates of the feature points in the camera coordinate system are derived, and then these coordinates are converted to coordinates in the world coordinate system. Furthermore, as... Figure 1 As shown, the arrows X, Y, and Z indicate the X-axis direction, Y-axis direction, and Z-axis direction.

[0079] like Figure 4 As shown, in step S130, the detection device 133 extracts objects by clustering feature points. The detection device 133 treats a set of feature points representing the same object as a group of points, and extracts this group of points as the object. Based on the coordinates of the feature points in the world coordinate system derived in step S120, the detection device 133 clusters feature points within a specified range, treating them as a group of points. The detection device 133 then treats the clustered group of points as an object. Furthermore, the feature point clustering performed in step S130 can be performed using various methods.

[0080] Next, in step S140, the detection device 133 derives the coordinates of the object in the world coordinate system. The object's coordinates can be derived from the coordinates of the feature points constituting the point group. The object's coordinates in the world coordinate system represent the relative position of the forklift 10 and the object. Specifically, the X-coordinate in the object's coordinates in the world coordinate system represents the distance from the origin to the object in the left-right direction, and the Y-coordinate represents the distance from the origin to the object in the front-back direction. The origin is, for example, the location of the stereo camera 132 with the X and Y coordinates set, and the Z-coordinate set to the coordinates of the road surface. The Euclidean distance from the location of the stereo camera 132 to the object can also be derived from the X and Y coordinates. The Z-coordinate in the object's coordinates in the world coordinate system represents the height of the object from the road surface.

[0081] Next, in step S150, the detection device 133 performs human detection processing. Human detection processing is the process of determining whether an object is a person. In this embodiment, the detection device 133 performs human detection processing on an image captured by either of the two cameras of the stereo camera 132. The detection device 133 converts the coordinates of the object in the world coordinate system obtained in step S140 into camera coordinates, and converts these camera coordinates into the coordinates of the image captured by the camera. The detection device 133 performs human detection processing on the coordinates of the object in the image. Human detection processing is performed, for example, using feature quantities. The detection device 133 extracts feature quantities of the coordinates of the object in the image. For example, methods for extracting feature quantities include extracting HOG (Histogram of Oriented Gradients) feature quantities, Haar-Like feature quantities, and other feature quantities of local regions in the image. The detection device 133 determines whether an object is a person by comparing the feature quantities extracted from the image with dictionary data. Dictionary data refers to, for example, data on feature quantities extracted from multiple known image data containing people. In the following description, objects that are different from people are sometimes referred to as obstacles.

[0082] <Hoichibu>

[0083] The notification unit 136 is a device for notifying the rider of the forklift 10. Examples of the notification unit 136 include a buzzer that notifies by sound, a lamp that notifies by light, or a combination thereof.

[0084] <Control performed by the control device>

[0085] The control device 81, the driving control device 63, and the object detection unit 131 are configured to exchange information with each other. The control device 81, the driving control device 63, and the object detection unit 131 exchange information with each other by communicating in accordance with vehicle communication protocols such as CAN (Controller Area Network) or LIN (Local Interconnect Network).

[0086] The control device 81 outputs the speed of the forklift 10. The speed of the forklift 10 can be derived using the detection results of the speed detection sensor 62, the gear ratio, the outer diameter of the drive wheel 12, and the steering angle detected by the tire angle sensor 88. The detection results of the speed detection sensor 62 can be obtained from the travel control device 63. The gear ratio and the outer diameter of the drive wheel 12 can be pre-stored in the storage unit 83. In the following description, speed refers to the speed of the forklift 10.

[0087] Control device 81 switches the connection and disconnection states of forward relay 111 and reverse relay 112. When no switchback operation is performed, control device 81 keeps forward relay 111 and reverse relay 112 connected. When a switchback operation is performed at a vehicle speed above the second vehicle speed threshold, control device 81 disconnects forward relay 111 and reverse relay 112. When the vehicle speed is below the second vehicle speed threshold, control device 81 keeps forward relay 111 and reverse relay 112 connected. A switchback operation refers to a change in the travel direction command given by steering lever 89. Changes in travel direction command include changes from a forward command to a reverse command and changes from a reverse command to a forward command. When forward relay 111 and reverse relay 112 are disconnected, regardless of the position of steering lever 89, the driving force of engine 31 will not be transmitted to power transmission mechanism 40 because solenoids 51 and 52 are demagnetized. That is, power transmission mechanism 40 is in a non-transmittable driving state. Therefore, the load on the power transmission mechanism 40 can be reduced when a turn-around operation is performed at a speed higher than the second speed threshold. The lower the second speed threshold, the less load is placed on the power transmission mechanism 40. On the other hand, the lower the second speed threshold, the longer the time until the forklift 10 changes direction during a turn-around operation. Based on these factors, the second speed threshold can be set arbitrarily.

[0088] The control device 81 activates the notification unit 136 by sending a notification command to the object detection unit 131. Specifically, the object detection unit 131 includes a working section that activates the notification unit 136 when a notification command is received.

[0089] <Reporting Area>

[0090] The control device 81 performs alarm control. Alarm control refers to control performed during the movement of the forklift 10, and is control by which the alarm unit 136 alarms based on the object detection status of the object by the object detection unit 131. First, the alarm area used for alarm control will be explained.

[0091] like Figure 5 As shown, a notification area AA1 for notification control is set within the detectable range of the object by the object detection unit 131. The detectable range of the object by the object detection unit 131 can also be described as the shooting range of the stereo camera 132. In this embodiment, the notification area AA1 is the same area as the detectable range of the object by the object detection unit 131. The notification area AA1 extends from the placement position of the stereo camera 132 toward the rear of the forklift 10 and in the width direction of the forklift 10. The notification area AA1 is defined by the X and Y coordinates in the world coordinate system.

[0092] <Expected trajectory>

[0093] The control device 81 derives the expected trajectory T of the forklift 10. The expected trajectory T refers to the trajectory that the forklift 10 is expected to travel. In this embodiment, the control device 81 derives the expected trajectory T of the forklift 10 when the traveling direction of the forklift 10 is the reverse direction.

[0094] The projected trajectory T can be derived based on the steering angle of the steering wheel 14 and the dimensions of the forklift 10. The dimensions of the forklift 10 include the dimensions [mm] from the center axis of the drive wheel 12 to the rear end of the vehicle body 11, the wheelbase [mm], and the width [mm]. Since the dimensions of the forklift 10 are known, they can be pre-stored in the storage unit 83 of the control device 81. The projected trajectory T is the trajectory between the trajectory LT traversed by the left end LE of the vehicle body 11 and the trajectory RT traversed by the right end RE of the vehicle body 11. The control device 81 derives the X and Y coordinates of the projected trajectory T extending towards the rear of the forklift 10 in the world coordinate system.

[0095] like Figure 5 and Figure 6 As shown, when the forklift 10 is traveling straight, the expected trajectory T is a straight line extending from the forklift 10 in the reverse direction. Figure 7 and Figure 8As shown, when the forklift 10 is turning, the predicted trajectory T is a trajectory that curves from the forklift 10 in the backward direction. When the forklift 10 is turning right, the predicted trajectory T extends to the right. When the forklift 10 is turning left, the predicted trajectory T extends to the left. It can be said that the control device 81 derives the predicted trajectory T that extends in the turning direction when the forklift 10 is turning.

[0096] Figure 6 The forklift shown is 10 times Figure 5 The forklift 10 in the shown state has a high speed. Similarly, Figure 8 The forklift shown is 10 times Figure 7 The forklift 10 shown has a high speed. For example... Figures 5-8 As shown, the higher the speed of forklift 10, the more the control device 81 extends the expected trajectory T in the direction of travel. In this embodiment, the trajectory derivation threshold YT is changed according to the vehicle speed. The trajectory derivation threshold YT is a threshold set for the Y-coordinate in the world coordinate system; the higher the vehicle speed, the further the Y-coordinate is from the forklift 10. The control device 81 derives the expected trajectory T from the forklift 10 to the trajectory derivation threshold YT. Furthermore, the extension of the expected trajectory T in the direction of travel as the forklift 10 speed increases is not limited to making the forklift 10 speed proportional to the length of the expected trajectory T in the direction of travel; any correlation is acceptable as long as the following relationship exists: if the forklift 10 speed increases, the length of the expected trajectory T in the direction of travel increases. The expected trajectory T is derived within the reporting area AA1.

[0097] <Notification Control>

[0098] The notification control is explained. Notification control is performed repeatedly according to a prescribed control cycle.

[0099] like Figure 9 As shown, in step S1, the control device 81 determines whether a specific condition is met. The specific condition is that the vehicle speed remains below a first vehicle speed threshold for a specified time. The vehicle speed is the absolute value of the speed calculated using the detection result of the vehicle speed detection sensor 62. The first vehicle speed threshold can be set to any value. In this embodiment, the first vehicle speed threshold is a value lower than a second vehicle speed threshold. The specified time is a time longer than the control cycle. The specified time is set such that if, due to the influence of noise, the vehicle speed is instantaneously determined to be below the first vehicle speed threshold even though it is above the first vehicle speed threshold, the specific condition is not determined to be met. If the determination result of step S1 is affirmative, the control device 81 performs the processing of step S2. If the determination result of step S1 is negative, the control device 81 performs the processing of step S3. If the specific condition is not met, the vehicle speed is above the first vehicle speed threshold. In other words, if the vehicle speed is above the first vehicle speed threshold, the processing of step S3 is performed.

[0100] In step S2, the control device 81 enters a normal state. The normal state refers to the state where the forklift 10's direction of travel is determined based on the detection result of the direction switch 90. If the direction lever 89 is in the forward position, the control device 81 determines that the forklift 10's direction of travel is forward. If the direction lever 89 is in the reverse position, the control device 81 determines that the forklift 10's direction of travel is reverse. When step S2 is completed, the control device 81 proceeds to step S4.

[0101] In step S3, the control device 81 enters a specific state. A specific state is one in which the previous state is considered to continue even if the direction command given by the steering lever 89 changes. If the direction command in the previous control cycle was a forward command, the control device 81 determines that the forward command continues even if a reverse command is input from the steering switch 90. If the direction command in the previous control cycle was a reverse command, the control device 81 determines that the reverse command continues even if a forward command is input from the steering switch 90. That is, during the period when the specific state continues, the direction command will not change even if the steering lever 89 is operated. In the specific state, the vehicle speed is above a first vehicle speed threshold. The second vehicle speed threshold is a value greater than the first vehicle speed threshold. Therefore, it can be said that when the specific state is in effect and the vehicle speed is above the second vehicle speed threshold, the control device 81 sets the power transmission mechanism 40 to a drive-off non-transmission state. When the processing of step S3 ends, the control device 81 proceeds to the processing of step S4.

[0102] In step S4, the control device 81 determines whether the reporting condition is met. The reporting condition refers to the condition under which a reporting is initiated via the reporting unit 136. The reporting condition is met when there is a possibility of contact between the forklift 10 and an object. The reporting condition varies depending on whether the object is a person or an obstacle. If the determination result in step S4 is affirmative, i.e., the reporting condition is met, the control device 81 proceeds to step S5. In step S5, the control device 81 issues a reporting notification via the reporting unit 136. The reporting condition will be explained below. The direction of travel used to determine the reporting condition varies depending on whether the control device 81 is in a normal state or a specific state. If the control device 81 is in a normal state, the direction of travel of the forklift 10 is determined based on the detection result of the direction switch 90. If the control device 81 is in a specific state, the direction of travel of the forklift 10 is determined based on the direction of travel command in the previous control cycle. In other words, in a specific state, the control device 81 determines whether there is a possibility of contact between the object and the forklift 10 based on the state before the change in the direction of travel command.

[0103] <The case of an object being a person>

[0104] The notification condition for an object being a person is that the forklift 10 is reversing and a person is present in the notification area AA1. When the object detected by the object detection unit 131 is a person, a notification is issued by the notification unit 136 when the forklift 10 is reversing and a person is present in the notification area AA1. Alternatively, the notification can be made stronger when a person is present within the expected trajectory T compared to when a person is present outside the expected trajectory T. Strengthening the notification can be achieved by increasing the volume of the buzzer if the notification unit 136 is a buzzer. Alternatively, if the notification unit 136 is a combination of a light and a buzzer, the notification can be switched from using only one of the lights or the buzzer to using both. This makes it easier for the rider to recognize the presence of an object within the expected trajectory T.

[0105] <The case where the object is an obstacle>

[0106] The reporting condition for an object being an obstacle is that the forklift 10 is reversing and there is an obstacle within the expected trajectory T. When the object detected by the object detection unit 131 is an obstacle, a report is made by the reporting unit 136 when the forklift 10 is reversing and there is an obstacle within the expected trajectory T.

[0107] [The Role of the Implementation Method]

[0108] like Figure 10 As shown, assuming the forklift 10 is in reverse, there is an object O1 behind the forklift 10. Arrow D1 indicates the actual direction of travel of the forklift 10. Arrow D2 indicates the direction of travel recognized by the control device 81. When the rider of the forklift 10 performs a turning action, the reverse command given by the steering lever 89 is switched to a forward command. When the direction of travel of the forklift 10 is switched, the speed of the forklift 10 continuously decreases. For example, when the direction of travel of the forklift 10 is switched from reverse to forward, the speed of the forklift 10 continuously decreases after the steering lever 89 is changed to the forward position. Furthermore, the direction of travel of the forklift 10 is switched to forward when the speed of the forklift 10 reaches 0 km / h. It can be said that when the direction of travel command given by the steering lever 89 changes when the speed of the forklift 10 is above the first speed threshold, the direction of travel of the forklift 10 is maintained at least until the speed of the forklift 10 falls below the first speed threshold.

[0109] Assume that the control device 81 remains in a normal state regardless of the speed of the forklift 10. In this case, when the direction lever 89 is changed to the forward position, the control device 81 will recognize the actual travel direction of the forklift 10 as the forward direction. In this case, even if the forklift 10 is actually still moving backward, the notification issued by the notification unit 136 will stop at the moment the direction lever 89 is changed to the forward position. That is, even though the distance L1 between the forklift 10 and the object O1 is constantly decreasing, the notification issued by the notification unit 136 will stop at the moment the direction lever 89 is changed to the forward position.

[0110] In contrast, in this embodiment, when the speed of the forklift 10 is above a first speed threshold, the control device 81 enters a specific state. In this specific state, even if the direction of travel command given by the steering lever 89 changes, the control device 81 recognizes that the state before the change continues. Figure 11 In the example shown, even if the reverse command changes to a forward command by performing a turnaround maneuver on the forklift 10, the control device 81 recognizes that the reverse command is still in effect. Therefore, the control device 81 can recognize the forklift 10's direction of travel as a reverse direction until the speed of the forklift 10 falls below a first speed threshold. Furthermore, even if the direction of travel command given by the direction lever 89 changes, the object detection unit 131 functions based on its state before the change, thus enabling it to detect objects in the same direction as the forklift 10's direction of travel. The object detection unit 131 functions to detect objects in the direction of travel of the forklift 10. Therefore, even while the forklift 10 continues to travel due to inertia, the notification unit 136 can continue to provide notification until the speed of the forklift 10 falls below the first speed threshold. If the speed and other conditions of the forklift 10 at the time of the turnaround are the same, the distance L1 between the forklift 10 and the object O1 at the time the notification by the notification unit 136 stops can be compared... Figure 10 The situation shown is short.

[0111] [Effects of the Implementation Method]

[0112] (1) The control device 81 enters a specific state when the vehicle speed is above the first speed threshold. Even if the direction of travel command given by the steering lever 89 changes, the control device 81 can recognize that the direction of travel of the forklift 10 is maintained until the speed of the forklift 10 falls below the first speed threshold. Compared with the case where the direction of travel of the forklift 10 is recognized based on the operating position of the steering lever 89 regardless of the speed of the forklift 10, the deviation between the direction of travel of the forklift 10 recognized by the control device 81 and the actual direction of travel of the forklift 10 can be suppressed. Furthermore, by enabling the object detection unit 131 to function based on the recognized direction of travel, objects can be detected in accordance with the direction of travel of the forklift 10.

[0113] (2) When the direction of travel command of the direction lever 89 changes in a specific state, the control device 81 determines whether the object and the forklift 10 are likely to come into contact based on the direction of travel before the change of direction command. Thus, when a turning action is performed, it is possible to prevent the situation where the notification by the notification unit 136 stops even though the forklift 10 has approached the object.

[0114] (3) The control device 81 sets the power transmission mechanism 40 to a non-drive state in a specific state. In this embodiment, the control device 81 sets the power transmission mechanism 40 to a non-drive state when the speed is above the second vehicle speed threshold within the speed range in which the control device 81 is in a specific state. When the power transmission mechanism 40 is in a non-drive state, the time until the forklift 10 changes direction when a reversing operation is performed becomes longer. For example, suppose the forklift 10 is traveling in a backward direction and the direction lever 89 is operated to switch the backward command to a forward command. At this time, when the power transmission mechanism 40 is in a non-drive state, the distance the forklift 10 travels in the backward direction becomes longer due to inertia. In other words, the distance required for the forklift 10 to change from a backward direction to a forward direction becomes longer. As a result, when the control device 81 is kept in a normal state regardless of the speed of the forklift 10, the distance at which the forklift 10's direction of travel, as perceived by the control device 81, deviates from the actual direction of travel becomes longer. When the notification unit 136 is issuing a notification if an object may come into contact with the forklift 10, the distance at which the notification unit 136 fails to issue a notification even though the forklift 10 has approached the object becomes longer. In contrast, by setting the control device 81 to a specific state, the distance at which the forklift 10's direction of travel, as perceived by the control device 81, deviates from the actual direction of travel becomes shorter. When the notification unit 136 is issuing a notification if an object may come into contact with the forklift 10, the distance at which the notification unit 136 fails to issue a notification even though the forklift 10 has approached the object becomes shorter.

[0115] (4) The control device 81 sets the power transmission mechanism 40 to a non-drive state via the interlocking device 110. The interlocking device 110 is provided to reduce the load on the power transmission mechanism 40 when a turn-around operation is performed at a speed of 2 or higher than the second speed threshold. On the other hand, by providing the interlocking device 110, the time until the forklift 10 changes direction when a turn-around operation is performed at a speed of 2 or higher is extended. By making the first speed threshold lower than the second speed threshold, when a turn-around operation is performed at a speed of 2 or higher, the control device 81 can recognize that the forklift 10's direction of travel is maintained from the start of the turn-around operation until the speed becomes lower than the first speed threshold. Thus, when a turn-around operation is performed, deviation between the direction of travel of the forklift 10 recognized by the control device 81 and the actual direction of travel of the forklift 10 can be suppressed.

[0116] (5) The specific condition is that the vehicle speed is below the first speed threshold and the state continues for a specified time. Due to the influence of noise, sometimes even if the vehicle speed is above the first speed threshold, it may be momentarily judged as the vehicle speed being below the first speed threshold. By setting the continuation of the specified time as a specific condition, it is possible to suppress false judgments caused by the influence of noise.

[0117] [Example of Change]

[0118] The implementation method can be modified as follows. The implementation method and the following variations can be combined with each other within the scope of technical inconsistency.

[0119] ○ For example Figure 12 As shown, the driving system 30 may also include a braking mechanism 200. The braking mechanism 200 includes a brake actuator 201, a brake wheel cylinder 202, and a brake controller 203.

[0120] Brake actuator 201 is an actuator that controls the working oil supplied to brake wheel cylinder 202. Brake actuator 201 controls the supply of working oil, for example, via a solenoid valve.

[0121] Brake wheel cylinder 202 is located on drive wheel 12. Brake wheel cylinder 202 can also be located on steering wheel 14. Brake wheel cylinder 202 generates friction braking force by pressing brake pads against brake discs with working oil supplied from brake actuator 201.

[0122] The hardware configuration of the brake controller 203 is, for example, the same as that of the control device 81. The brake controller 203 controls the brake actuator 201 according to instructions from the control device 81. It can be said that the control device 81 can control the braking mechanism 200 by sending instructions to the brake controller 203.

[0123] The control device 81 can also, in a specific state, apply braking force to the forklift 10 by controlling the braking mechanism 200 instead of setting the power transmission mechanism 40 to a drive-off state. Alternatively, in a specific state, the control device 81 can not only set the power transmission mechanism 40 to a drive-off state but also apply braking force to the forklift 10 by controlling the braking mechanism 200.

[0124] The control device 81 may also prevent the power transmission mechanism 40 from being set to a non-drive state under certain conditions. In this case, the forklift 10 may not have the interlock device 110.

[0125] ○ The reporting conditions can also be changed regardless of whether the object is a person or an obstacle. In this case, the detection device 133 may not perform person detection processing. The reporting condition may be that the forklift 10 is reversing and there is an object within the expected trajectory T. The reporting condition may also be that the forklift 10 is reversing and there is an object in the reporting area AA1. If the expected trajectory T is not used as the reporting condition, the control device 81 may not derive the expected trajectory T.

[0126] The control device 81 can also control the deceleration of the forklift 10 by recognizing its direction of travel. For example, if the notification condition is met, deceleration control can be performed to slow down the forklift 10. In this case, the notification unit 136 may or may not be notified.

[0127] The control device 81 can also set the power transmission mechanism 40 to a non-drive state via an inching valve. The inching valve adjusts whether the driving force of the engine 31 is distributed to the power transmission mechanism 40 or to the hydraulic pump. Alternatively, the power transmission mechanism 40 can be set to a non-drive state by preventing the distribution of the driving force of the engine 31 to the power transmission mechanism 40 via the inching valve.

[0128] ○A specific condition could also be that the vehicle speed is lower than the first vehicle speed threshold.

[0129] The power transmission mechanism 40 can also be configured to switch between a drive transmission state and a drive non-transmission state according to instructions from the control device 81. In this case, during a reversing operation, the control device 81 may give an instruction to the power transmission mechanism 40, thereby setting the power transmission mechanism 40 to the drive non-transmission state.

[0130] The object detection unit 131 can also detect the position of objects in the forward direction of the forklift 10. In this case, the stereo camera 132 is positioned facing forward of the forklift 10. When the object detection unit 131 detects the position of an object in the forward direction of the forklift 10, the reporting area AA1 becomes a region extending forward from the forklift 10. In this case, the reporting control is performed by reversing the "back" and "forward" directions as described in the embodiment.

[0131] As the object detection unit 131, it can also be an object detection unit capable of detecting the position of objects existing in either the backward or forward direction within the travel direction of the forklift 10. For example, a forward stereo camera and a backward stereo camera can be provided, or a fisheye camera can be provided. In this case, the reporting area AA1 includes a forward area extending from the forklift 10 and a rear area extending from the forklift 10. The control device 81 changes the reporting conditions according to the travel direction of the forklift 10. For example, if the travel direction of the forklift 10 is backward, the control device 81 reports the reporting unit 136 using the same reporting conditions as in the embodiment. If the travel direction of the forklift 10 is forward, the control device 81 reports the reporting unit 136 by replacing the backward reporting conditions in the reporting conditions of the embodiment with forward reporting conditions.

[0132] The direction-of-travel determination unit can be any type of device, as long as it can be operated by the rider of the forklift 10. For example, the direction-of-travel determination unit can be a button.

[0133] The object detection unit 131 can also replace the stereo camera 132 by using a monocular camera, a ToF (Time of Flight) camera, a LIDAR (Laser Imaging Detection and Ranging) camera, a millimeter-wave radar, etc. The object detection unit 131 can also be a component combining multiple sensors such as the stereo camera 132 and LIDAR.

[0134] Alternatively, a notification unit 136 may be provided in a part other than the object detection unit 131.

[0135] Alternatively, the control device 81 can be configured to directly activate the notification unit 136.

[0136] ○ Forklift 10 can also be a forklift that can switch between automatic and manual operation.

[0137] ○ Forklift 10 can also be an electric forklift that is driven by a motor.

[0138] Forklift 10 can also be a forklift whose speed and direction of travel are determined by a steering lever. Such a forklift is, for example, a reach forklift.

[0139] Alternatively, the speed sensor 34 can be configured as a direction of travel detection unit.

[0140] ○ The detection device 133 can also be used as a control device.

[0141] Industrial vehicles can also be tractors used for transporting goods, picking machines used for picking operations, etc.

Claims

1. An industrial vehicle, characterized in that, have: The direction of travel detection unit detects the direction of travel of industrial vehicles; A vehicle speed detection sensor that detects the speed of the industrial vehicle; A direction-determining unit that determines the direction of travel of the industrial vehicle; An object detection unit that detects the position of an object existing in the direction of travel of the industrial vehicle; as well as Control device, The control device enters a specific state when the speed of the industrial vehicle detected by the vehicle speed detection sensor is above the first vehicle speed threshold. The specific state is as follows: even if the travel direction command given by the travel direction determination unit changes, the control device recognizes that the state before the change is still continuing, and the object detection unit functions based on the state before the change. The industrial vehicle is equipped with a notification unit that notifies the industrial vehicle when an object detected by the object detection unit is likely to come into contact with it. The control device determines, in the specific state, whether the object and the industrial vehicle are likely to come into contact, based on the state before the change. The control device outputs the predicted trajectory of the industrial vehicle. The projected trajectory extends in a straight line from the industrial vehicle toward the reverse direction when the industrial vehicle is traveling straight, and extends in a straight line from the industrial vehicle toward the turning direction when the industrial vehicle is turning. If the object is present in the expected trajectory, the notification by the notification unit continues until the speed of the industrial vehicle becomes lower than the first speed threshold.

2. The industrial vehicle according to claim 1, wherein, The industrial vehicle has the following features: Engine; and Power transmission mechanism The power transmission mechanism can switch between a drive transmission state, in which the driving force of the engine is transmitted to the power transmission mechanism, and a drive non-transmission state, in which the driving force of the engine is not transmitted to the power transmission mechanism. The control device sets the power transmission mechanism to the drive non-transmission state in the specific state.

3. The industrial vehicle according to claim 2, wherein, The industrial vehicle is equipped with an interlocking device that sets the power transmission mechanism to the non-transmission drive state. When the travel direction command given by the travel direction determination unit changes when the speed of the industrial vehicle is above the second speed threshold, the control device sets the power transmission mechanism to the drive non-transmission state through the interlocking device. The first vehicle speed threshold is set to be lower than the second vehicle speed threshold.

4. An industrial vehicle, characterized in that, have: The direction of travel detection unit detects the direction of travel of industrial vehicles; A vehicle speed detection sensor that detects the speed of the industrial vehicle; A direction-determining unit that determines the direction of travel of the industrial vehicle; An object detection unit that detects the position of an object existing in the direction of travel of the industrial vehicle; as well as Control device, The control device enters a specific state when the speed of the industrial vehicle detected by the vehicle speed detection sensor is above the first vehicle speed threshold. The specific state is as follows: even if the travel direction command given by the travel direction determination unit changes, the control device recognizes that the state before the change is still continuing, and the object detection unit functions based on the state before the change. The industrial vehicle has the following features: Engine; and Power transmission mechanism The power transmission mechanism can switch between a drive transmission state, in which the driving force of the engine is transmitted to the power transmission mechanism, and a drive non-transmission state, in which the driving force of the engine is not transmitted to the power transmission mechanism. The control device sets the power transmission mechanism to the drive non-transmission state in the specific state.

5. The industrial vehicle according to claim 4, wherein, The industrial vehicle is equipped with an interlocking device that sets the power transmission mechanism to the non-transmission drive state. When the travel direction command given by the travel direction determination unit changes when the speed of the industrial vehicle is above the second speed threshold, the control device sets the power transmission mechanism to the drive non-transmission state through the interlocking device. The first vehicle speed threshold is set to be lower than the second vehicle speed threshold.

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