Industrial vehicles

Abstract

To prevent industrial vehicles from coming into contact with obstacles on their sides. [Solution] The industrial vehicle comprises a vehicle body, a side camera, and a control device. The control device is Depending on the steering angle and direction of travel of the industrial vehicle, a stopping area and a speed limiting area located outside the stopping area are set on the side of the vehicle. If an obstacle is present in the speed limiting area, the control device allows the industrial vehicle to travel up to the set speed limit. If an obstacle is present in the stopping area, the control device controls the industrial vehicle to stop.

Description

Technical Field

[0001] The present disclosure relates to an industrial vehicle.

Background Art

[0002] The industrial vehicle disclosed in Patent Document 1 includes a plurality of cameras that image the surroundings of the industrial vehicle and a processing device. The processing device recognizes an object in the image captured by the camera. The processing device calculates the position of the object with respect to the industrial vehicle. The processing device determines the volume of an alarm based on the position of the object and the line-of-sight direction of the driver.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] There are cases where it is required to prevent contact between an industrial vehicle and an obstacle on the side of the industrial vehicle.

Means for Solving the Problems

[0005] [[ID= forty-two ]] The industrial vehicle that solves the above problems is an industrial vehicle, comprising a vehicle body, a side detection unit that detects an obstacle existing on the side of the vehicle body, and a control device that sets, on the side of the vehicle body, a stop area and a vehicle speed limit area located outside the stop area according to the steering angle and the traveling direction of the industrial vehicle, wherein when the obstacle exists in the vehicle speed limit area, the control device allows the industrial vehicle to travel with the set vehicle speed upper limit as the upper limit, and when the obstacle exists in the stop area, the control device controls to stop the industrial vehicle.

[0006] The control device sets a stopping area and a speed limiting area according to the steering angle and direction of travel of the industrial vehicle. If an obstacle is present in the speed limiting area, the industrial vehicle is permitted to travel up to the speed limit. By prohibiting travel at speeds faster than the speed limit, contact between the industrial vehicle and the obstacle is reduced. When the obstacle enters the stopping area due to the movement of at least one of the industrial vehicle or the obstacle, the industrial vehicle stops. This reduces the likelihood of contact between the industrial vehicle and obstacles on its sides.

[0007] With respect to the above-mentioned industrial vehicle, the control device may increase the left-right dimensions of the vehicle speed limiting area and the stopping area according to the steering angle. With respect to the above-mentioned industrial vehicle, the control device may, if the obstacle is located in the vehicle speed limit area when the industrial vehicle is being started, allow the industrial vehicle to travel up to the vehicle speed limit, and if the obstacle is located in the stopping area when the industrial vehicle is being started, control the industrial vehicle to stop.

[0008] With respect to the above-mentioned industrial vehicle, the control device may allow the industrial vehicle to accelerate up to a set acceleration limit if the obstacle is located within the vehicle speed limit area. In the industrial vehicle described above, the side detection unit may be a monocular camera.

[0009] With respect to the above-mentioned industrial vehicle, the obstacle may include a person, and the control device may control the vehicle to allow it to travel up to the upper limit of the vehicle speed when the person is in the speed-restriction area, and to stop the vehicle when the person is in the stopping area. [Effects of the Invention]

[0010] According to the present invention, it is possible to suppress contact between an industrial vehicle and an obstacle on its side. [Brief explanation of the drawing]

[0011] [Figure 1]Figure 1 is a perspective view of an industrial vehicle. [Figure 2] Figure 2 is a schematic diagram of an industrial vehicle. [Figure 3] Figure 3 is a flowchart showing the process performed by the detection device. [Figure 4] Figure 4 is a flowchart showing the process performed by the detection device. [Figure 5] Figure 5 is a schematic diagram showing the rear and lateral ranges. [Figure 6] Figure 6 shows the lateral restriction area when the direction of travel is in reverse and the industrial vehicle is moving straight. [Figure 7] Figure 7 shows the lateral restriction area when the direction of travel is in reverse and the industrial vehicle is in the first left turn position. [Figure 8] Figure 8 shows the lateral restriction area when the direction of travel is in reverse and the industrial vehicle is in a second left turn state. [Figure 9] Figure 9 shows the lateral restriction area when the direction of travel is in reverse and the industrial vehicle is in a third left turn. [Figure 10] Figure 10 shows the lateral restriction area when the direction of travel is forward and the industrial vehicle is moving straight. [Figure 11] Figure 11 shows the lateral restriction area when the industrial vehicle is moving forward and in the first left turn position. [Figure 12] Figure 12 shows the lateral restriction area when the industrial vehicle is moving forward and in the second left turn position. [Figure 13] Figure 13 shows the lateral restriction area when the industrial vehicle is moving forward and in the third left turn position. [Figure 14] Figure 14 is a flowchart showing the stop control performed by the control device. [Figure 15] Figure 15 shows a situation where an obstacle is present in a vehicle speed limit area. [Figure 16]FIG. 16 is a diagram showing a state where an obstacle exists in the stop area. [Figure 17] FIG. 17 is a time chart showing the relationship among the position of the obstacle, the accelerator operation, the brake operation, and the vehicle speed.

Mode for Carrying Out the Invention

[0012] An embodiment of an industrial vehicle will be described. As shown in FIG. 1, the industrial vehicle 10 includes a vehicle body 11, two front wheels 12 and 13, two rear wheels 14 and 15, a driver's seat 16, and a loading and unloading device 20. The industrial vehicle 10 is, for example, a forklift or a towing tractor. The industrial vehicle 10 of the present embodiment is a counterbalanced forklift. The two front wheels 12 and 13 include a left front wheel 12 and a right front wheel 13. The two front wheels 12 and 13 are drive wheels. The two rear wheels 14 and 15 include a left rear wheel 14 and a right rear wheel 15. The two rear wheels 14 and 15 are steering wheels. The front, rear, left, and right refer to the front, rear, left, and right of the industrial vehicle 10. The vehicle body 11 includes a head guard 17 provided above the driver's seat 16.

[0013] The loading and unloading device 20 is provided in front of the driver's seat 16. The loading and unloading device 20 includes a mast 21, two forks 22, and a lift cylinder 23. The mast 21 is provided at the front of the vehicle body 11. The forks 22 are provided so as to be able to move up and down together with the mast 21. A load is loaded on the forks 22. The lift cylinder 23 is a hydraulic cylinder. The mast 21 moves up and down by the expansion and contraction of the lift cylinder 23. As the mast 21 moves up and down, the forks 22 move up and down. The industrial vehicle 10 of the present embodiment performs a traveling operation and a loading and unloading operation by an operation by an operator.

[0014] The industrial vehicle 10 includes a steering wheel 18. The steering wheel 18 is provided in front of the driver's seat 16. The steering wheel 18 is operated by an operator. By operating the steering wheel 18, the steering angle of the industrial vehicle 10 changes.

[0015] As shown in Figure 2, the industrial vehicle 10 is equipped with a control device 31 that controls driving and cargo handling. The control device 31 comprises a processor 32 and a storage unit 33. The processor 32 is, for example, a CPU (Central Processing Unit), a GPU (Graphics Processing Unit), or a DSP (Digital Signal Processor). The storage unit 33 includes RAM (Random Access Memory) and ROM (Read Only Memory). The storage unit 33 stores a program for operating the control device 31. The storage unit 33 stores program code or instructions configured to cause the processor 32 to execute processing. The storage unit 33, i.e., the computer-readable medium, includes any available medium that can be accessed by a general-purpose or dedicated computer. The control device 31 may be composed of hardware circuits such as an ASIC (Application Specific Integrated Circuit) or an FPGA (Field Programmable Gate Array). The control device 31, which is a processing circuit, may include one or more processors that operate according to a computer program, one or more hardware circuits such as an ASIC or FPGA, or a combination thereof.

[0016] The industrial vehicle 10 is equipped with an accelerator control unit 34. The accelerator control unit 34 is, for example, a pedal. The accelerator control unit 34 is operated by an operator riding in the industrial vehicle 10.

[0017] The industrial vehicle 10 is equipped with an accelerator sensor 35. The accelerator sensor 35 detects the amount of operation of the accelerator operating unit 34, i.e., the accelerator opening degree. The accelerator sensor 35 outputs an electrical signal corresponding to the accelerator opening degree to the control device 31. The control device 31 can recognize the accelerator opening degree from the electrical signal from the accelerator sensor 35.

[0018] The industrial vehicle 10 is equipped with a direction control unit 36. The direction control unit 36 ​​is, for example, a lever. The direction control unit 36 ​​is operated when determining the direction of travel of the industrial vehicle 10. The direction control unit 36 ​​is operated from a neutral position to a forward position or a reverse position. When moving the industrial vehicle 10 forward, the direction control unit 36 ​​is operated from a neutral position to a forward position. When moving the industrial vehicle 10 backward, the direction control unit 36 ​​is operated from a neutral position to a reverse position.

[0019] The industrial vehicle 10 is equipped with a direction sensor 37. The direction sensor 37 detects the operating position of the direction control unit 36. The direction sensor 37 outputs an electrical signal to the control device 31 corresponding to the operating direction of the direction control unit 36. The control device 31 can recognize the operating position of the direction control unit 36 ​​from the electrical signal from the direction sensor 37. The control device 31 controls the direction of travel of the industrial vehicle 10 according to the operating position of the direction control unit 36.

[0020] The industrial vehicle 10 can travel in neutral, forward, or reverse. When the direction of travel is neutral, the direction control unit 36 ​​is in the neutral position. When the direction of travel is neutral, operating the accelerator control unit 34 will not move the industrial vehicle 10. When the direction of travel is forward, the direction control unit 36 ​​is in the forward position. When the direction of travel is forward, operating the accelerator control unit 34 will move the industrial vehicle 10 forward. When the direction of travel is reverse, the direction control unit 36 ​​is in the reverse position. When the direction of travel is reverse, operating the accelerator control unit 34 will move the industrial vehicle 10 in reverse.

[0021] The industrial vehicle 10 is equipped with a tire angle sensor 38. The tire angle sensor 38 detects the steering angle of the rear wheels 14 and 15. The tire angle sensor 38 outputs an electrical signal corresponding to the steering angle to the control device 31. The control device 31 can recognize the steering angle from the electrical signal from the tire angle sensor 38. The steering angle is the inclination of the rear wheels 14 and 15 with respect to the longitudinal direction of the industrial vehicle 10. When the steering angle is 0, the rear wheels 14 and 15 are facing the longitudinal direction of the industrial vehicle 10. When the steering angle is negative, the industrial vehicle 10 is turned to the left. When the steering angle is positive, the industrial vehicle 10 is turned to the right. The ± of the steering angle indicates the direction of the turn. Therefore, the further the steering angle is from 0, that is, the larger the absolute value of the steering angle, the larger the steering angle.

[0022] The industrial vehicle 10 is equipped with a drive motor 41. The drive motor 41 rotates the front wheels 12 and 13, causing the industrial vehicle 10 to move. A drive motor 41 is provided for each of the front wheels 12 and 13.

[0023] The industrial vehicle 10 is equipped with a travel control device 43. The travel control device 43 is a motor driver that controls the rotational speed of the travel motor 41. A travel control device 43 is provided for each travel motor 41. The travel control device 43 controls the rotational speed of the travel motor 41 so that it follows a target rotational speed instructed by the control device 31.

[0024] The industrial vehicle 10 is equipped with a rotational speed sensor 42. The rotational speed sensor 42 detects the rotational speed of the drive motor 41. The rotational speed sensor 42 is, for example, a rotary encoder. The rotational speed sensor 42 outputs an electrical signal corresponding to the rotational speed of the drive motor 41 to the drive control device 43. The drive control device 43 can recognize the rotational speed of the drive motor 41 from the electrical signal of the rotational speed sensor 42.

[0025] The industrial vehicle 10 is equipped with an obstacle detection unit 51. The obstacle detection unit 51 comprises one stereo camera 52, two side cameras 53 and 54, an alarm unit 55, and a detection device 56.

[0026] As shown in Figure 1, the stereo camera 52 is positioned, for example, on the head guard 17. The stereo camera 52 is positioned to provide a bird's-eye view of the road surface on which the industrial vehicle 10 travels, from above the industrial vehicle 10. In this embodiment, the stereo camera 52 images the area behind the industrial vehicle 10. The stereo camera 52 comprises two cameras positioned spaced apart from each other, and imaging is performed by both cameras.

[0027] The two side cameras 53 and 54 are positioned, for example, on the head guard 17. The two side cameras 53 and 54 are positioned to provide a bird's-eye view of the side of the industrial vehicle 10 from above. The two side cameras 53 and 54 include a left-side camera 53 that captures the left side of the industrial vehicle 10 and a right-side camera 54 that captures the right side of the industrial vehicle 10. The side cameras 53 and 54 are monocular cameras.

[0028] The alarm unit 55 provides an alarm to at least one of the people and / or the operator in the vicinity of the industrial vehicle 10. The alarm unit 55 is, for example, a buzzer. The hardware configuration of the detection device 56 is, for example, similar to that of the control device 31. The detection device 56 includes, for example, a processor 57 and a storage unit 58.

[0029] The detection device 56 detects obstacles by acquiring images from the stereo camera 52 and the side cameras 53 and 54. Obstacles are objects that may obstruct the movement of the industrial vehicle 10. Obstacles include people and non-human objects. First, the control performed by the detection device 56 when detecting an obstacle using the image acquired from the stereo camera 52 will be described.

[0030] As shown in Figure 3, in step S10, the detection device 56 acquires an image from the stereo camera 52. Next, in step S11, the detection device 56 acquires a disparity image by performing stereo processing. Stereo processing is a process that compares images captured by the two cameras of the stereo camera 52 and calculates the disparity, which is the difference in the number of pixels between the two images for the same feature points captured in each image. Feature points are, for example, points that represent the outline of an obstacle in the image. A disparity image is one in which the disparity [px] is associated with each pixel.

[0031] Next, in step S12, the detection device 56 derives the coordinates of the feature points in the world coordinate system, which is a coordinate system in real space. As shown in Figure 1, the world coordinate system is a coordinate system in which, with the industrial vehicle 10 positioned on a horizontal plane, the axis extending in the width direction of the industrial vehicle 10 in the horizontal direction is the X-axis, the axis perpendicular to the X-axis in the horizontal direction is the Y-axis, and the axis extending in the vertical direction is the Z-axis. The detection device 56 derives the coordinates of the feature points in the camera coordinate system from the baseline length of the stereo camera 52, the focal length of the stereo camera 52, and the disparity image obtained in step S11. The camera coordinate system is a coordinate system with the stereo camera 52 as the origin. The detection device 56 converts the coordinates of the feature points in the camera coordinate system to coordinates in the world coordinate system.

[0032] Next, in step S13, the detection device 56 extracts obstacles by clustering feature points. The detection device 56 groups together feature points that are assumed to represent the same obstacle from among the feature points that represent a part of the obstacle, and extracts this point group as an obstacle. The clustering of feature points performed in step S13 can be carried out using various methods.

[0033] Next, in step S14, the detection device 56 derives the coordinates of the obstacle in the world coordinate system. The coordinates of the obstacle can be derived from the coordinates of the feature points that make up the point cloud. The coordinates of the obstacle in the world coordinate system represent the relative position between the industrial vehicle 10 and the obstacle. More specifically, the X coordinate of the obstacle in the world coordinate system represents the distance from the origin to the obstacle in the left-right direction. The Y coordinate of the obstacle in the world coordinate system represents the distance from the origin to the obstacle in the front-back direction. The origin of the world coordinate system is, for example, a coordinate system where the X and Y coordinates are the position of the stereo camera 52 and the Z coordinate is the road surface. The Z coordinate of the obstacle in the world coordinate system represents the height of the obstacle from the road surface.

[0034] Next, in step S15, the detection device 56 performs a person detection process. The person detection process determines whether an obstacle is a person or not. In this embodiment, the detection device 56 performs the person detection process on an image captured by one of the two cameras of the stereo camera 52. The detection device 56 converts the coordinates of the obstacle in the world coordinate system obtained in step S14 into camera coordinates, and then converts the camera coordinates into the coordinates of the image captured by the camera. The detection device 56 performs the person detection process on the coordinates of the obstacle in the image. The person detection process is performed, for example, using feature quantities. The detection device 56 extracts feature quantities from the coordinates of the obstacle in the image. The feature quantities are, for example, HOG (Histogram of Oriented Gradients) features or Haar-Like features. The detection device 56 determines whether an obstacle is a person or not by comparing the feature quantities extracted from the image with dictionary data. The dictionary data is, for example, feature quantity data extracted from each of multiple images in which a person is pictured. Obstacles that were not determined to be people in step S15 are objects. Step S15 enables the detection device 56 to recognize the coordinates of people and non-people objects in the world coordinate system.

[0035] Next, we will explain the control performed by the detection device 56 when it detects an obstacle using images acquired from the side cameras 53 and 54. The detection device 56 detects obstacles individually using the image acquired from the left camera 53 and the image acquired from the right camera 54.

[0036] As shown in Figure 4, in step S20, the detection device 56 acquires images from the side cameras 53 and 54. Next, in step S21, the detection device 56 performs depth estimation. Depth estimation is a method for estimating the distance between the object represented in each pixel of the image and the side cameras 53 and 54. Depth estimation can be performed using machine learning, such as SfM (Structure from Motion) or a convolutional neural network (CNN). Depth information may also be obtained separately from a distance sensor.

[0037] Next, in step S22, the detection device 56 uses depth information to derive the coordinates of the feature points in the world coordinate system. The detection device 56 uses depth information to derive the coordinates of the feature points in the side camera coordinate system. The side camera coordinate system is a coordinate system with the side cameras 53 and 54 as the origin. From the image acquired from the left camera 53, the coordinates of the feature points in the coordinate system with the left camera 53 as the origin are derived. From the image acquired from the right camera 54, the coordinates of the feature points in the coordinate system with the right camera 54 as the origin are derived. The detection device 56 converts the coordinates of the feature points in the side camera coordinate system to coordinates in the world coordinate system.

[0038] Next, in step S23, the detection device 56 extracts obstacles by clustering the feature points. Step S23 is the same process as in step S13. Next, in step S24, the detection device 56 derives the coordinates of the obstacle in the world coordinate system. The process in step S24 is the same as the process in step S14.

[0039] Next, in step S25, the detection device 56 performs human detection processing. The human detection processing is the same as the human detection processing in step S15. The detection device 56 only needs to perform human detection processing on the images acquired from the side cameras 53 and 54. By step S25, the detection device 56 can recognize the coordinates of people and non-people in the world coordinate system.

[0040] As shown in Figure 5, the detection device 56 uses images acquired from the stereo camera 52 to detect obstacles in the rear range R1 behind the vehicle body 11. The detection device 56 uses images acquired from the side cameras 53 and 54 to detect obstacles located in the lateral ranges R2 and R3 on the side of the vehicle body 11. The detection device 56 uses images acquired from the left camera 53 to detect obstacles located in the left-side range R2 on the left side of the vehicle body 11. The detection device 56 uses images acquired from the right camera 54 to detect obstacles located in the right-side range R3 on the right side of the vehicle body 11.

[0041] The size of the left range R2 and the right range R3 are identical. The left range R2 and the right range R3 are symmetrical with respect to a straight line passing through the center position in the width direction of the industrial vehicle 10. The longitudinal dimension L1 of the lateral ranges R2 and R3 is longer than the longitudinal dimension L2 of the industrial vehicle 10. The longitudinal dimension L2 of the industrial vehicle 10 is, for example, the distance from the tip of the fork 22 to the rear end of the vehicle body 11. The front ends of the lateral ranges R2 and R3 are located in front of the front end of the vehicle body 11. The rear ends of the lateral ranges R2 and R3 are located behind the rear end of the vehicle body 11. Therefore, the lateral ranges R2 and R3 include the area in front of the vehicle body 11 and the area behind the vehicle body 11. This allows for the detection of obstacles in front of the vehicle body 11 and obstacles behind the vehicle body 11 from the images acquired from the left camera 53 and the right camera 54. The left-side camera 53 detects obstacles on the left side of the vehicle body 11. The right-side camera 54 detects obstacles on the right side of the vehicle body 11. The left-side camera 53 and the right-side camera 54 are part of the side detection unit.

[0042] The rear range R1 is wider than the lateral ranges R2 and R3. The longitudinal dimension L3 of the rear range R1 is longer than the longitudinal dimension L1 of the lateral ranges R2 and R3. The lateral dimension L4 of the rear range R1 is longer than the lateral dimension L5 of the lateral ranges R2 and R3. Parts of the rear range R1 and parts of the lateral ranges R2 and R3 overlap. The portions of the lateral ranges R2 and R3 that protrude rearward from the rear end of the vehicle body 11 overlap with the rear range R1.

[0043] <Restricted Area> The control device 31 performs stop control. Stop control is a control that stops the industrial vehicle 10 according to the position of the obstacle detected by the obstacle detection unit 51. First, the restricted area used for stop control will be explained.

[0044] As shown in Figures 6 to 13, the control device 31 changes the restricted area A according to the direction of travel and steering angle of the industrial vehicle 10. The control device 31 can recognize the direction of travel of the industrial vehicle 10 by acquiring the detection result of the direction sensor 37. The control device 31 can recognize the steering angle by acquiring the detection result of the tire angle sensor 38. The restricted area A is defined, for example, by the XY coordinates of the world coordinate system.

[0045] Restricted area A includes a rear stop area AR, which is defined by the rear range R1. The rear stop area AR is an area where the industrial vehicle 10 is stopped if an obstacle detected by an image acquired from the stereo camera 52 is located within the rear stop area AR.

[0046] Restricted area A includes the lateral restricted area AS set by the lateral ranges R2 and R3. Lateral restricted area AS is an area where the speed and starting of the industrial vehicle 10 are restricted when an obstacle detected by images acquired from the lateral cameras 53 and 54 is located within the lateral restricted area AS.

[0047] <When the direction of travel is reverse and the industrial vehicle is moving straight ahead> As shown in Figure 6, when the industrial vehicle 10 is moving in the reverse direction and is moving straight, the central area A1 is set as the rear stopping area AR. The lateral restriction area AS is not set. The central area A1 is the area facing the industrial vehicle 10 in the front-rear direction.

[0048] The straight-ahead state is defined as a steering angle greater than or equal to -1 angle and less than or equal to +1 angle. The 1st angle is set so that the industrial vehicle 10 can be considered to be moving in a straight line. The 1st angle can be set appropriately, for example, within the range of 3° to 8°.

[0049] <When the direction of travel is reverse and the industrial vehicle is in the first turning position> As shown in Figure 7, when the industrial vehicle 10 is moving in the reverse direction and is in the first turning state, the rear stopping area AR is set as the central area A1, in addition to one of the left area A2 and the right area A3. The lateral restriction area AS is set as the forward direction area A6 and the opposite direction area A7.

[0050] Left-side region A2 is the region to the left of central region A1. Left-side region A2 is the region that industrial vehicle 10 passes through when it turns left in the reverse direction. The right-side region A3 is the region to the right of the central region A1. The right-side region A3 is the region that the industrial vehicle 10 passes through when it turns right in the reverse direction.

[0051] The first turning state is a state where the absolute value of the steering angle is greater than the first angle, but less than or equal to the second angle. The second angle is a larger angle than the first angle. The second angle can be set appropriately, for example, within the range of 15° to 30°. The first turning state is a state where the steering angle is greater than that of the straight-ahead state. The first turning state is, for example, the state when passing through a gentle curve.

[0052] The first turning state includes the first turning state to the left and the first turning state to the right. The first turning state to the left is a state where the steering angle is -2 angles or greater and less than -1 angles. The first turning state to the right is a state where the steering angle is +2 angles or less and greater than +1 angles.

[0053] When the industrial vehicle 10 is moving in the reverse direction and is in a first left turn state, the central area A1 and the left side area A2 are set as the rear stopping area AR. The direction of travel region A6 is a region for detecting obstacles present in the direction of travel. When the direction of travel is in reverse, the direction of travel region A6 is a region that extends behind the rear end of the vehicle body 11. For example, the direction of travel region A6 is a region set along the vehicle body 11, extending from a position adjacent to the front wheels 12 and 13 in the left-right direction to behind the rear end of the vehicle body 11. The direction of travel region A6 is the restricted area A on the direction of travel side.

[0054] The anti-direction area A7 is an area for detecting obstacles located on the opposite side of the direction of travel. When the direction of travel is in reverse, the anti-direction area A7 is an area that extends forward of the front end of the vehicle body 11. For example, the anti-direction area A7 is an area set along the vehicle body 11, extending from a position adjacent to the front wheels 12 and 13 in the left-right direction to an area forward of the tip of the fork 22. The anti-direction area A7 may also be set to extend to the front end of a load L loaded on the fork 22. The anti-direction area A7 is a restriction area A on the opposite side of the direction of travel.

[0055] When the industrial vehicle 10 is moving in the reverse direction and is in a first left turn state, the direction of travel region A6 is set along the left edge of the industrial vehicle 10. For example, the direction of travel region A6 is a rectangular area extending from a position adjacent to the left front wheel 12 to a position overlapping with the left side region A2. The opposite direction of travel region A7 is set along the right edge of the industrial vehicle 10. For example, the opposite direction of travel region A7 is a rectangular area extending from a position adjacent to the right front wheel 13 to a position in front of the tip of the fork 22.

[0056] When the industrial vehicle 10 is moving in the reverse direction and is in a first rightward turn state, the central area A1 and the right-side area A3 are set as the rearward stopping area AR. When the industrial vehicle 10 is moving in the reverse direction and is in a first right turn state, the direction of travel region A6 is set along the right edge of the industrial vehicle 10. For example, the direction of travel region A6 extends from a position adjacent to the right front wheel 13 to a position overlapping with the right side region A3. The opposite direction of travel region A7 is set along the left edge of the industrial vehicle 10. For example, the opposite direction of travel region A7 extends from a position adjacent to the left front wheel 12 to a position in front of the tip of the fork 22.

[0057] The lateral restriction area AS includes the starting restriction area AS1 and the vehicle speed restriction area AS2. The starting restriction area AS1 is an example of a stopping area. The starting restriction area AS1 and the vehicle speed restriction area AS2 are set in the direction of travel area A6 and the opposite direction of travel area A7, respectively. The starting restriction area AS1 and the vehicle speed restriction area AS2 are set on the sides of the vehicle body 11. The vehicle speed restriction area AS2 is located outside the starting restriction area AS1. The vehicle speed restriction area AS2 is an area where, if an obstacle is present in the vehicle speed restriction area AS2, the industrial vehicle 10 is permitted to travel up to a set upper limit on its speed. The starting restriction area AS1 is an area where, if an obstacle is present in the starting restriction area AS1, control is performed to stop the industrial vehicle 10.

[0058] The width LS1 of the starting restriction area AS1 can be arbitrarily set by the manufacturer or user of the industrial vehicle 10. For example, the width LS1 of the starting restriction area AS1 is set so that the industrial vehicle 10 does not come into contact with an obstacle when the industrial vehicle 10 starts moving. The width LS1 of the starting restriction area AS1 is the left-right dimension of the starting restriction area AS1.

[0059] The width LS2 of the vehicle speed limit area AS2 is the measurement error that may occur in the position of obstacles measured by the side cameras 53 and 54 × the width LS1 of the starting limit area AS1 + margin. If there is a 20% measurement error in the position of obstacles measured by the side cameras 53 and 54, then the width LS2 of the vehicle speed limit area AS2 is 0.2 × the width LS1 of the starting limit area AS1 + margin. The margin can be arbitrarily set by the manufacturer of the industrial vehicle 10 or the user of the industrial vehicle 10. The margin is a value of 0 or greater. The width LS2 of the vehicle speed limit area AS2 is the left-right dimension of the vehicle speed limit area AS2. Note that the width LS1 of the starting limit area AS1, the width LS2 of the vehicle speed limit area AS2, and their ratios shown may differ from reality.

[0060] Figure 7 shows the restricted area A when the industrial vehicle 10 is in the first left-turning position. In the example shown in Figure 7, since the industrial vehicle 10 is turning to the left, the central area A1 and the left-side area A2 are set as the rear stopping area AR, but for the sake of explanation, the right-side area A3 is also shown.

[0061] <When the direction of travel is reverse and the industrial vehicle is in a second turning position> As shown in Figure 8, when the industrial vehicle 10 is moving in the reverse direction and is in the second turning state, the rear stopping area AR is set as the central area A1, in addition to one of the left area A2 and the right area A3. The lateral restriction area AS is set as the direction of travel area A6 and the opposite direction of travel area A7. The second turning state is a state in which the absolute value of the steering angle is greater than the second angle and less than or equal to the third angle. The third angle is an angle greater than the second angle. The third angle can be appropriately set, for example, in the range of 50° to 70°. The second turning state is a state in which the steering angle is greater than that of the first turning state. The second turning state is, for example, the state when passing through a right-angled passage.

[0062] The second turning state includes the second turning state to the left and the second turning state to the right. The second turning state to the left is a state where the steering angle is -3 degrees or greater and less than -2 degrees. The second turning state to the right is a state where the steering angle is +3 degrees or less and greater than +2 degrees.

[0063] When the industrial vehicle 10 is moving in the reverse direction and is in a second left turn state, the central area A1 and the left side area A2 are set as the rear stopping area AR. When the industrial vehicle 10 is moving in the reverse direction and is in the second turning state, the direction of travel region A6 becomes larger than the direction of travel region A6 set in the first turning state. Within the direction of travel region A6, the width L11 is longer than in the first turning state in the region from the point adjacent to the position between the front wheels 12, 13 and the rear wheels 14, 15 to the rear end of the direction of travel region A6. This width L11 is the same as, for example, the left-right dimension LA2 of the left-side region A2, or the left-right dimension LA3 of the right-side region A3 (see Figure 7). When the width of the direction of travel region A6 differs depending on the position, as in the direction of travel region A6 shown in Figure 8, the width of the direction of travel region A6 means the maximum width of the direction of travel region A6. In the example shown in Figure 8, the width of the direction of travel region A6 is width L11.

[0064] The size of the counter-direction region A7 set when the industrial vehicle 10 is moving in the reverse direction and the industrial vehicle 10 is in the second turning state is the same as the counter-direction region A7 set when it is in the first turning state.

[0065] When the industrial vehicle 10 is in the second turning state, the width L11 of the direction of travel area A6 is larger than that set in the first turning state. As the width L11 of the direction of travel area A6 increases, the width LS1 of the starting restriction area AS1 and the width LS2 of the vehicle speed restriction area AS2 also increase. When the steering angle increases, the amount of lateral movement increases even if the rotational speed of the front wheels 12 and 13 is the same. For this reason, the width L11 of the direction of travel area A6 is increased. As the width L11 of the direction of travel area A6 increases, the width LS1 of the starting restriction area AS1 and the width LS2 of the vehicle speed restriction area AS2 also increase. If the width of the starting restriction area AS1 differs depending on the position, the width LS1 of the starting restriction area AS1 represents the maximum width of the starting restriction area AS1. If the width of the vehicle speed restriction area AS2 differs depending on the position, the width LS2 of the vehicle speed restriction area AS2 represents the maximum width of the vehicle speed restriction area AS2.

[0066] When increasing the width LS1 of the starting restriction area AS1 and the width LS2 of the vehicle speed restriction area AS2, the widths LS1 and LS2 of the starting restriction area AS1 and vehicle speed restriction area AS2 may be increased by the same ratio. Alternatively, the ratio by which the width LS1 of the starting restriction area AS1 is increased may be greater than or less than the ratio by which the width LS2 of the vehicle speed restriction area AS2 is increased.

[0067] If the size is the same in the first turning state and the second turning state, as in the counter-direction area A7, the width LS1 of the starting restriction area AS1 and the width LS2 of the vehicle speed restriction area AS2 are maintained.

[0068] When the industrial vehicle 10 is moving in the reverse direction and is in a second left turn, the direction of travel region A6 is set along the left edge of the industrial vehicle 10. For example, the direction of travel region A6 extends from a position adjacent to the left front wheel 12 to a position overlapping with the left side region A2. The opposite direction of travel region A7 is set along the right edge of the industrial vehicle 10. For example, the opposite direction of travel region A7 extends from a position adjacent to the right front wheel 13 to a position in front of the tip of the fork 22.

[0069] When the industrial vehicle 10 is moving in the reverse direction and is in a second right turn state, the central area A1 and the right-side area A3 are set as the rear stopping area AR. When the industrial vehicle 10 is moving in the reverse direction and is in a second right turn, the direction of travel region A6 is set along the right edge of the industrial vehicle 10. For example, the direction of travel region A6 extends from a position adjacent to the right front wheel 13 to a position overlapping with the right side region A3. The opposite direction of travel region A7 is set along the left edge of the industrial vehicle 10. For example, the opposite direction of travel region A7 extends from a position adjacent to the left front wheel 12 to a position in front of the tip of the fork 22.

[0070] Figure 8 shows the restricted area A when the industrial vehicle 10 is in the left second turn position. The restricted area A when the industrial vehicle 10 is in the right second turn position is the same shape as the restricted area A when the industrial vehicle 10 is in the left second turn position, but reversed horizontally. For this reason, the restricted area A when the industrial vehicle 10 is in the right second turn position is not shown.

[0071] <When the direction of travel is in reverse, and the industrial vehicle is in a third turning position> As shown in Figure 9, when the industrial vehicle 10 is moving in the reverse direction and is in the third turning state, the rear stopping area AR is set as the central area A1, in addition to one of the left area A2 and the right area A3. Also, the lateral restriction area AS is set as the area in the direction of travel A6 and the area in the opposite direction of travel A7. The third turning state is a state in which the absolute value of the steering angle is greater than the third angle. The third turning state is a state in which the steering angle is greater than that of the second turning state. The third turning state is, for example, the state in which the industrial vehicle 10 is turned in place.

[0072] The third turning state includes the third turning state to the left and the third turning state to the right. The third turning state to the left is when the steering angle is less than -3 degrees. The third turning state to the right is when the steering angle is greater than +3 degrees.

[0073] When the industrial vehicle 10 is moving in the reverse direction and is in a third left turn state, the central area A1 and the left side area A2 are set as the rear stopping area AR. When the industrial vehicle 10 is moving in the reverse direction and is in the third turning state, the direction of travel region A6 is larger than the direction of travel region A6 set in the second turning state. The longitudinal dimension L21 of the direction of travel region A6 is longer than in the second turning state. For example, the longitudinal dimension L21 of the direction of travel region A6 is longer such that the front end of the direction of travel region A6 is located in front of the front end of the vehicle body 11. The width L12 of the direction of travel region A6 is larger throughout the longitudinal direction than in the second turning state. The width L12 is larger than, for example, the lateral dimension LA2 of the left region A2 or the lateral dimension LA3 of the right region A3.

[0074] When the industrial vehicle 10 is moving in the reverse direction and is in the third turning state, the counter-direction region A7 is larger than the counter-direction region A7 set when it is in the second turning state. The longitudinal dimension L22 of the counter-direction region A7 is longer than in the second turning state. For example, the longitudinal dimension L22 of the counter-direction region A7 is longer such that the rear end of the counter-direction region A7 is located behind the front wheels 12 and 13. The width L13 of the counter-direction region A7 is longer throughout the longitudinal direction than in the second turning state. The width L13 is, for example, the same as the lateral dimension LA2 of the left region A2, or the lateral dimension LA3 of the right region A3.

[0075] When the industrial vehicle 10 is in the third turning state, the width L12 of the direction of travel area A6 becomes larger than the width L11 of the direction of travel area A6 set when it is in the second turning state. As the width L12 of the direction of travel area A6 increases, the width LS1 of the starting restriction area AS1 and the width LS2 of the vehicle speed restriction area AS2 also increase. In addition, the width LS1 of the starting restriction area AS1 and the width LS2 of the vehicle speed restriction area AS2 set in the opposite direction of travel area A7 also increase as the width L13 of the opposite direction of travel area A7 increases.

[0076] When the industrial vehicle 10 is moving in the reverse direction and is in a third left turn position, the direction of travel region A6 is set along the left edge of the industrial vehicle 10. For example, the direction of travel region A6 extends from a position adjacent to the fork 22 to a position overlapping with the left side region A2. The opposite direction of travel region A7 is set along the right edge of the industrial vehicle 10. For example, the opposite direction of travel region A7 extends from a position behind the right front wheel 13 to a position in front of the tip of the fork 22.

[0077] When the industrial vehicle 10 is moving in the reverse direction and is in a third right turn state, the central area A1 and the right-side area A3 are set as the rear stopping area AR. When the industrial vehicle 10 is moving in the reverse direction and is in a third right turn position, the direction of travel region A6 is set along the right edge of the industrial vehicle 10. For example, the direction of travel region A6 extends from a position adjacent to the fork 22 to a position overlapping with the right-side region A3. The opposite direction of travel region A7 is set along the left edge of the industrial vehicle 10. For example, the opposite direction of travel region A7 extends from a position behind the left front wheel 12 to a position in front of the tip of the fork 22.

[0078] Figure 9 shows the restricted area A when the industrial vehicle 10 is in the left third turn position. The restricted area A when the industrial vehicle 10 is in the right third turn position is the same shape as the restricted area A when the industrial vehicle 10 is in the left third turn position, but reversed horizontally. For this reason, the restricted area A when the industrial vehicle 10 is in the right third turn position is not shown.

[0079] <When the direction of travel is forward and the industrial vehicle is moving straight ahead> As shown in Figure 10, when the industrial vehicle 10 is traveling in the forward direction and is moving in a straight line, the restricted area A is not set.

[0080] <When the direction of travel is forward and the industrial vehicle is in the first turning position> As shown in Figure 11, when the industrial vehicle 10 is traveling in the forward direction and is in the first turning state, the rear stopping area AR is not set. The lateral restriction area AS consists of a forward direction area A6 and a non-forward direction area A7.

[0081] When the direction of travel is forward, the direction of travel region A6 is the region that extends forward beyond the tip of the fork 22. The direction of travel region A6 set when the direction of travel is forward extends further forward than the counter-direction region A7 set when the direction of travel is reverse. The direction of travel region A6 set when the direction of travel is forward may be set to extend further forward than the front end of the load L loaded on the fork 22.

[0082] The direction of travel region A6 is, for example, a rectangular region set along the vehicle body 11, extending from a position adjacent to the front wheels 12 and 13 in the left-right direction to a point in front of the tip of the fork 22.

[0083] When the direction of travel is forward, the anti-travel region A7 is the region that extends to the rear end of the vehicle body 11. The anti-travel region A7 is, for example, a rectangular region set along the vehicle body 11, extending from a position adjacent to the front wheels 12 and 13 in the left-right direction to the rear end of the vehicle body 11.

[0084] Even when the direction of travel is forward, a starting restriction area AS1 and a vehicle speed restriction area AS2 are set in both the direction of travel area A6 and the opposite direction of travel area A7, respectively. When the industrial vehicle 10 is moving forward and in a first left turn state, the direction of travel region A6 is set along the left edge of the industrial vehicle 10. For example, the direction of travel region A6 is a rectangular area extending from a position adjacent to the left front wheel 12 to a position in front of the tip of the fork 22. The opposite direction of travel region A7 is set along the right edge of the industrial vehicle 10. For example, the opposite direction of travel region A7 is a rectangular area extending from a position adjacent to the right front wheel 13 to the rear end of the vehicle body 11.

[0085] When the industrial vehicle 10 is moving forward and in a first right turn state, the direction of travel region A6 is set along the right edge of the industrial vehicle 10. For example, the direction of travel region A6 is a rectangular area extending from a position adjacent to the right front wheel 13 to a position in front of the tip of the fork 22. The opposite direction of travel region A7 is set along the left edge of the industrial vehicle 10. For example, the opposite direction of travel region A7 is a rectangular area extending from a position adjacent to the left front wheel 12 to the rear end of the vehicle body 11.

[0086] Figure 11 shows the restricted area A when the industrial vehicle 10 is in the first left turn position. The restricted area A when the industrial vehicle 10 is in the first right turn position is the same shape as the restricted area A when the industrial vehicle 10 is in the first left turn position, but reversed horizontally. For this reason, the restricted area A when the industrial vehicle 10 is in the first right turn position is not shown.

[0087] <When the direction of travel is forward and the industrial vehicle is in the second turning position> As shown in Figure 12, when the industrial vehicle 10 is traveling in the forward direction and is in the second turning state, the rear stopping area AR is not set. The forward direction area A6 and the opposite direction area A7 are set as the lateral restriction area AS.

[0088] When the industrial vehicle 10 is traveling in the forward direction and is in the second turning state, the direction of travel region A6 becomes larger than the direction of travel region A6 set in the first turning state. Within the direction of travel region A6, the width L31 of the region from the point adjacent to the fork 22 in the left-right direction to the front end of the direction of travel region A6 becomes longer than in the first turning state. The width L31 is, for example, the same as the left-right dimension LA2 of the left region A2, or the left-right dimension LA3 of the right region A3. The counter-direction of travel region A7 set when the industrial vehicle 10 is traveling in the forward direction and is in the second turning state is the same as the counter-direction of travel region A7 set in the first turning state.

[0089] When the industrial vehicle 10 is in the second turning state, the width L31 of the direction of travel area A6 becomes larger than when it is in the first turning state. As a result of the increased width L31 of the direction of travel area A6, the width LS1 of the starting restriction area AS1 and the width LS2 of the vehicle speed restriction area AS2 also increase. If the size is the same in the first turning state and the second turning state, as in the opposite direction of travel area A7, the size of the starting restriction area AS1 and the vehicle speed restriction area AS2 is maintained.

[0090] When the industrial vehicle 10 is moving forward and in a second left turn, the direction of travel region A6 is set along the left edge of the industrial vehicle 10. For example, the direction of travel region A6 extends from a position adjacent to the left front wheel 12 to a position in front of the tip of the fork 22. The opposite direction of travel region A7 is set along the right edge of the industrial vehicle 10. For example, the opposite direction of travel region A7 extends from a position adjacent to the right front wheel 13 to the rear end of the vehicle body 11.

[0091] When the industrial vehicle 10 is moving forward and in a second right turn position, the direction of travel region A6 is set along the right edge of the industrial vehicle 10. For example, the direction of travel region A6 extends from a position adjacent to the right front wheel 13 to a position ahead of the tip of the fork 22. The opposite direction of travel region A7 is set along the left edge of the industrial vehicle 10. For example, the opposite direction of travel region A7 extends from a position adjacent to the left front wheel 12 to the rear end of the vehicle body 11.

[0092] Figure 12 shows the restricted area A when the industrial vehicle 10 is in the left second turn position. The restricted area A when the industrial vehicle 10 is in the right second turn position is the same shape as the restricted area A when the industrial vehicle 10 is in the left second turn position, but reversed horizontally. For this reason, the restricted area A when the industrial vehicle 10 is in the right second turn position is not shown.

[0093] <When the direction of travel is forward and the industrial vehicle is in a third turning position> As shown in Figure 13, when the industrial vehicle 10 is traveling in the forward direction and is in the third turning state, the rear stopping area AR is not set. The lateral restriction area AS consists of the forward direction area A6 and the opposite direction area A7.

[0094] When the industrial vehicle 10 is traveling in the forward direction and is in the third turning state, the direction of travel region A6 is larger than the direction of travel region A6 set in the second turning state. The longitudinal dimension L41 of the direction of travel region A6 is longer than in the second turning state. For example, the longitudinal dimension L41 of the direction of travel region A6 is longer so that the rear end of the direction of travel region A6 extends to a point adjacent to the position between the front wheels 12, 13 and the rear wheels 14, 15. The width L32 of the direction of travel region A6 is longer throughout the longitudinal direction than in the second turning state. The width L32 is, for example, larger than the left-right dimension LA2 of the left-side region A2, or the left-right dimension LA3 of the right-side region A3.

[0095] When the industrial vehicle 10 is traveling in the forward direction and is in the third turning state, the anti-traveling region A7 is larger than the anti-traveling region A7 set when it is in the second turning state. The longitudinal dimension L42 of the anti-traveling region A7 is longer than in the second turning state. For example, the longitudinal dimension L42 of the anti-traveling region A7 is longer so that the front end of the anti-traveling region A7 is located in front of the front wheels 12 and 13. The width L33 of the anti-traveling region A7 is longer throughout the longitudinal direction than in the second turning state. The width L33 is, for example, the same as the lateral dimension LA2 of the left region A2, or the lateral dimension LA3 of the right region A3.

[0096] When the industrial vehicle 10 is in the third turning state, the width L32 of the direction of travel area A6 becomes larger than when it is in the second turning state. As the width L32 of the direction of travel area A6 increases, the width LS1 of the starting restriction area AS1 and the width LS2 of the vehicle speed restriction area AS2 also increase. In addition, the width LS1 of the starting restriction area AS1 and the width LS2 of the vehicle speed restriction area AS2 set in the opposite direction of travel area A7 also increase as the width L33 of the opposite direction of travel area A7 increases.

[0097] When the industrial vehicle 10 is moving forward and is in a third left turn position, the direction of travel region A6 is set along the left end of the industrial vehicle 10. For example, the direction of travel region A6 extends from a point adjacent to the position between the left front wheel 12 and the left rear wheel 14 to a point in front of the tip of the fork 22. The opposite direction of travel region A7 is set along the right end of the industrial vehicle 10. For example, the opposite direction of travel region A7 extends from a position in front of the right front wheel 13 to the rear end of the vehicle body 11.

[0098] When the industrial vehicle 10 is moving forward and is in a third right turn position, the direction of travel region A6 is set along the right edge of the industrial vehicle 10. For example, the direction of travel region A6 extends from a point adjacent to the position between the right front wheel 13 and the right rear wheel 15 to a point in front of the tip of the fork 22. The opposite direction of travel region A7 is set along the left edge of the industrial vehicle 10. For example, the opposite direction of travel region A7 extends from a position in front of the left front wheel 12 to the rear end of the vehicle body 11.

[0099] Figure 13 shows the restricted area A when the industrial vehicle 10 is in the left third turn position. The restricted area A when the industrial vehicle 10 is in the right third turn position is the same shape as the restricted area A when the industrial vehicle 10 is in the left third turn position, but reversed horizontally. For this reason, the restricted area A when the industrial vehicle 10 is in the right third turn position is not shown.

[0100] As described above, the larger the steering angle, the larger the forward-direction area A6 and the counter-forward-direction area A7 become. In this embodiment, the forward-direction area A6 and the counter-forward-direction area A7 are increased in stages according to the turning state. When the absolute value of the steering angle becomes larger than the second angle, and the first turning state becomes the second turning state, the forward-direction area A6 becomes larger. When the absolute value of the steering angle becomes larger than the third angle, and the second turning state becomes the third turning state, the forward-direction area A6 and the counter-forward-direction area A7 become larger. As the width of the forward-direction area A6 and the width of the counter-forward-direction area A7 increase, the width LS1 of the starting restriction area AS1 and the width LS2 of the vehicle speed restriction area AS2 also increase accordingly. The width LS1 of the starting restriction area AS1 and the width LS2 of the vehicle speed restriction area AS2 increase according to the steering angle.

[0101] <Stop control> The stop control will now be explained. The stop control is performed repeatedly at a predetermined control cycle, for example, while the industrial vehicle 10 is ignited. The industrial vehicle 10 becomes drivable when the ignition is ignited. Furthermore, the stop control in this embodiment aims to restrict the start and speed when the industrial vehicle 10 starts moving. In other words, the stop control is a start restriction control that restricts the start of the industrial vehicle 10.

[0102] The following stop control is performed for obstacles in the lateral restriction area AS. If the industrial vehicle 10 attempts to start moving while an obstacle is present in the rear stop area AR, the start of the industrial vehicle 10 will be restricted.

[0103] As shown in Figure 14, in step S30, the control device 31 determines whether or not a person is present in the departure restriction area AS1. The control device 31 obtains the person's coordinates in the world coordinate system from the detection device 56. The control device 31 then determines whether or not a person is present in the departure restriction area AS1, which is set according to the direction of travel and steering angle. The departure restriction area AS1 is defined by the XY coordinates in the world coordinate system. Therefore, by determining whether or not the person's XY coordinates in the world coordinate system are within the departure restriction area AS1, it is possible to determine whether or not a person is present in the departure restriction area AS1. If the determination result in step S30 is positive, the control device 31 proceeds to step S34. If the determination result in step S30 is negative, the control device 31 proceeds to step S31.

[0104] In step S31, the control device 31 determines whether or not a person is present in the vehicle speed limit area AS2. The vehicle speed limit area AS2 is defined by the XY coordinates of the world coordinate system. Therefore, by determining whether or not the person's XY coordinates in the world coordinate system are within the vehicle speed limit area AS2, it is possible to determine whether or not a person is present in the vehicle speed limit area AS2. If the result of the determination in step S31 is affirmative, the control device 31 proceeds to step S32. If the result of the determination in step S31 is negative, the control device 31 proceeds to step S38.

[0105] In step S32, the control device 31 determines whether or not the industrial vehicle 10 is being started. Starting means raising the vehicle speed of the industrial vehicle 10 from below a threshold to above a threshold. The threshold is set to determine whether or not the industrial vehicle 10 is stopped. The threshold may be 0 [km / h]. The threshold may be set to a value greater than 0, taking measurement errors into consideration. For example, the threshold may be set within the range of 0 [km / h] to 0.5 [km / h].

[0106] Starting the vehicle is performed when the vehicle speed is below a threshold, the direction control unit 36 ​​is operated to the forward or reverse position, and the accelerator control unit 34 is operated. Whether or not the direction control unit 36 ​​is operated to the forward or reverse position can be determined from the detection result of the direction sensor 37. Whether or not the accelerator control unit 34 is operated can be determined from the detection result of the accelerator sensor 35.

[0107] Furthermore, if step S32 is determined to be positive, it is determined that the starting operation is being performed until the determination of step S31 or step S32 becomes negative in the next control cycle. In other words, if the determination result of step S32 is positive while a person is in the vehicle speed limit area AS2, it is determined that the starting operation is being performed as long as the person is in the vehicle speed limit area AS2.

[0108] In step S33, the control device 31 limits the vehicle speed. The control device 31 limits the vehicle speed by setting a vehicle speed upper limit [km / h]. The vehicle speed upper limit is lower than the maximum speed that the industrial vehicle 10 can reach. If the target vehicle speed calculated from the detection result of the accelerator sensor 35 is less than the vehicle speed upper limit, the control device 31 calculates the target rotational speed from the target vehicle speed calculated from the detection result of the accelerator sensor 35. If the target vehicle speed calculated from the detection result of the accelerator sensor 35 is equal to or greater than the vehicle speed upper limit, the control device 31 calculates the target rotational speed using the vehicle speed upper limit instead of the target vehicle speed. This prevents the speed of the industrial vehicle 10 from exceeding the vehicle speed upper limit.

[0109] The control device 31 limits acceleration along with vehicle speed. The control device 31 limits acceleration by setting an acceleration upper limit [m / s^2]. The acceleration upper limit is lower than the maximum acceleration that the industrial vehicle 10 can achieve. The control device 31 controls the industrial vehicle 10 so that its acceleration does not exceed the acceleration upper limit. For example, the control device 31 outputs a command to the driving control device 43 indicating a target acceleration. The driving control device 43 controls the rotational speed of the driving motor 41 so that the acceleration of the industrial vehicle 10 becomes the target acceleration. When the acceleration upper limit is set, the control device 31 outputs a value less than or equal to the acceleration upper limit as the target acceleration to the driving control device 43. This prevents the acceleration of the industrial vehicle 10 from exceeding the acceleration upper limit.

[0110] In step S34, the control device 31 determines whether or not the vehicle speed is being restricted. That is, it determines whether or not the vehicle speed restriction in step S33 was performed in the previous control cycle. If the determination result in step S34 is affirmative, it can be said that the person moved from the vehicle speed restriction area AS2 to the start restriction area AS1 due to the movement of at least one of the person and the industrial vehicle 10. If the determination result in step S34 is affirmative, the control device 31 proceeds to step S35. If the determination result in step S34 is negative, the control device 31 proceeds to step S36.

[0111] In step S35, the control device 31 controls the vehicle so that its speed becomes 0 km / h. That is, the control device 31 controls the industrial vehicle 10 to stop. The industrial vehicle 10 stops by giving a command to the driving control device 43. The control device 31 may also perform deceleration limiting. For example, the control device 31 performs deceleration limiting by setting a deceleration upper limit value [m / s^2]. The deceleration upper limit value is lower than the maximum deceleration that the industrial vehicle 10 can achieve. The control device 31 controls the industrial vehicle 10 so that its deceleration does not exceed the deceleration upper limit value. For example, the control device 31 outputs a command to the driving control device 43 indicating a target deceleration. The driving control device 43 controls the rotational speed of the driving motor 41 so that the deceleration of the industrial vehicle 10 becomes the target deceleration. When the deceleration upper limit value is set, the control device 31 outputs a value less than or equal to the deceleration upper limit value as the target deceleration to the driving control device 43. This prevents the deceleration of the industrial vehicle 10 from exceeding the deceleration upper limit value.

[0112] In step S36, the control device 31 determines whether or not a starting operation has been performed. The determination in step S36 is made by the same process as the determination in step S32. If the determination result in step S36 is positive, the control device 31 proceeds to step S37. If the determination result in step S36 is negative, the control device 31 proceeds to step S38.

[0113] In step S37, the control device 31 implements a starting restriction. The starting restriction prohibits the industrial vehicle 10 from starting. The starting restriction is implemented, for example, by setting the vehicle speed limit [km / h] to 0 [km / h].

[0114] In step S38, the control device 31 performs normal control. Normal control is to control the vehicle speed so that it corresponds to the operation of the accelerator pedal 34. If a vehicle speed limit or a start limit is in place, the control device 31 releases it.

[0115] [Operation of this embodiment] As shown in Figure 15, assume that at time T0, when the industrial vehicle 10 starts moving, a person M1 is present as an obstacle in the vehicle speed restriction area AS2. In this case, the industrial vehicle 10 is permitted to travel at a speed below the upper limit of the vehicle speed.

[0116] As shown in Figure 16, assume that at time T1, at least one of the industrial vehicle 10 and person M1 moves, causing person M1 to enter the departure restriction area AS1. As shown in Figure 17, at time T0, the industrial vehicle 10 is permitted to travel, so the vehicle speed increases by operating the accelerator pedal 34. The control device 31 limits the acceleration, so even if the accelerator pedal 34 is operated a large amount, the vehicle speed increases gradually. When the vehicle speed reaches the upper limit, the vehicle speed is maintained at the upper limit.

[0117] When person M1 enters the starting restriction area AS1 at time T1, the control device 31 controls the vehicle speed to 0 [km / h]. Because the control device 31 applies a deceleration limit, the vehicle speed decreases gradually.

[0118] In the example shown in Figure 17, the operator of the industrial vehicle 10 applies the brakes at time T2. As a result, the vehicle speed becomes 0 at time T2. In this way, even though the accelerator is being pressed, the vehicle speed decreases, notifying the operator of the industrial vehicle 10 of the presence of person M1 and prompting them to apply the brakes. If the brakes are not applied at time T2, the vehicle speed will continue to decrease slowly after time T2, and the industrial vehicle 10 will come to a stop.

[0119] In this way, when a person M1 is to the side of the industrial vehicle 10, contact between the industrial vehicle 10 and the person M1 can be suppressed. Furthermore, in order to prevent contact between the industrial vehicle 10 and person M1 standing to its side, it is also possible to omit the vehicle speed restriction area AS2 and only provide the starting restriction area AS1. In this case, however, it may lead to a decrease in the work efficiency of the industrial vehicle 10. A detailed explanation follows below.

[0120] For example, suppose that the positional accuracy of obstacles detected by the side cameras 53 and 54 may have a measurement error of ±20% in the left-right direction. Suppose we want to stop the industrial vehicle 10 when there is an obstacle 1.5 [m] away from it in the left-right direction. Due to the measurement error, an obstacle that is 1.5 [m] away may be measured as being 1.8 [m] away, so the width of the starting restriction area AS1 needs to be set to 1.8 [m]. An obstacle that is 2.25 [m] away may be measured as being 1.8 [m] away due to the measurement error. Therefore, if we try to stop the industrial vehicle 10 when there is an obstacle 1.5 [m] away, the industrial vehicle 10 may be stopped by an obstacle that is 2.25 [m] away. In this case, the industrial vehicle 10 may not be able to move due to the obstacle that is 2.25 [m] away, leading to a decrease in work efficiency.

[0121] In contrast, as in the embodiment, by setting a vehicle speed limiting area AS2 outside the starting restriction area AS1, the vehicle speed of the industrial vehicle 10 can be reduced by the vehicle speed limiting area AS2 before the obstacle enters the starting restriction area AS1. Assuming a margin of 0, the width LS2 of the vehicle speed limiting area AS2 is 0.2 × the width LS1 of the starting restriction area AS1. If the width LS1 of the starting restriction area AS1 is 1.5 [m], then the width LS2 of the vehicle speed limiting area AS2 is 0.3 [m]. In this case, if, due to measurement error, an obstacle located 1.5 [m] away is measured to be located 1.8 [m] away, the vehicle speed of the industrial vehicle 10 will be limited by the vehicle speed limiting area AS2. That is, although the industrial vehicle 10 cannot be stopped by an obstacle located 1.5 [m] away, its vehicle speed can be limited. Depending on the measurement error, even if an obstacle is measured to be located 1.5 [m] away, it may actually be closer, at a distance of 1.2 [m]. Even in this case, the speed of the industrial vehicle 10 is limited by the vehicle speed restriction area AS2, thus preventing contact between the industrial vehicle 10 and obstacles.

[0122] Furthermore, if an obstacle is located 2.25 m away, measurement errors may cause it to be measured as being 1.8 m away. In this case, although the vehicle speed will be limited, the industrial vehicle 10 can still travel. Therefore, a decrease in the work efficiency of the industrial vehicle 10 can be suppressed.

[0123] [Effects of this embodiment] (1) The control device 31 sets a starting restriction area AS1 and a vehicle speed restriction area AS2 according to the steering angle and direction of travel of the industrial vehicle 10. If an obstacle is present in the vehicle speed restriction area AS2, the industrial vehicle 10 is allowed to travel up to the vehicle speed limit. By prohibiting travel at a speed faster than the vehicle speed limit, it is difficult for the industrial vehicle 10 to come into contact with the obstacle. When the obstacle enters the starting restriction area AS1 due to the movement of at least one of the industrial vehicle 10 and the obstacle, the industrial vehicle 10 stops. This makes it possible to suppress contact between the industrial vehicle 10 and an obstacle on its side.

[0124] (2) The control device 31 increases the vehicle speed limit area AS2 and the starting limit area AS1 as the steering angle increases. When the steering angle is large, the turning center approaches the industrial vehicle 10, which increases the amount of lateral movement when the industrial vehicle 10 moves. By increasing the vehicle speed limit area AS2 and the starting limit area AS1 as the steering angle increases, contact with obstacles on the side of the industrial vehicle 10 can be suppressed.

[0125] (3) The control device 31 limits the vehicle speed and starts when the industrial vehicle 10 is being started. After the industrial vehicle 10 has started moving, the vehicle speed and starts are no longer limited, thus preventing a decrease in work efficiency.

[0126] (4) When an obstacle is present in the vehicle speed limit area AS2, the control device 31 allows the industrial vehicle 10 to accelerate up to the set acceleration limit. As a result, the industrial vehicle 10 accelerates gradually, further suppressing contact with obstacles on the sides.

[0127] (5) The side cameras 53 and 54 are monocular cameras. When using monocular cameras, the range in which the position of obstacles can be detected with high accuracy is narrower compared to when using stereo cameras. On the other hand, by using monocular cameras, manufacturing costs can be reduced compared to when stereo cameras are used as side cameras 53 and 54.

[0128] When the industrial vehicle 10 moves in reverse, the amount of movement of the industrial vehicle 10 in the lateral direction is less than the amount of movement of the industrial vehicle 10 in the rearward direction. Therefore, the lateral ranges R2 and R3 can be made narrower than the rearward range R1. Consequently, even when monocular cameras are used as lateral cameras 53 and 54 to detect the position of obstacles in the lateral ranges R2 and R3, the position of the obstacles can be detected with high accuracy. Therefore, by using monocular cameras as lateral cameras 53 and 54, it is possible to reduce manufacturing costs while accurately detecting the position of obstacles in the lateral ranges R2 and R3.

[0129] (6) The control device 31 limits the speed of the industrial vehicle 10 when a person is located in the speed limit area AS2 as an obstacle. The control device 31 also limits the starting of the industrial vehicle 10 when a person is located in the starting limit area AS1 as an obstacle. If the obstacle is an object other than a person, the starting and speed limits of the industrial vehicle 10 are not imposed, thus improving work efficiency. For example, if the starting and speed limits are imposed by walls surrounding the industrial vehicle 10 or by the load L being handled, work efficiency may decrease. Since the starting and speed limits are not imposed by walls or the load L being handled, work efficiency is improved.

[0130] The embodiment can be implemented with the following modifications. The embodiment and the following modifications can be combined with each other to the extent that they do not contradict each other technically. ○The control device 31 may impose a speed limit if an object other than a person is present as an obstacle in the speed limit area AS2. The control device 31 may also impose a start restriction if an object other than a person is present as an obstacle in the start restriction area AS1.

[0131] The industrial vehicle 10 may be equipped with one camera that has a wide-angle lens, such as a fisheye lens. In this case, the camera may detect obstacles in the right-side area A3 and the left-side area A2. The camera is a side-detection unit.

[0132] ○The side cameras 53 and 54 may be stereo cameras. ○The control device 31 may perform speed limiting and starting limiting even after the industrial vehicle 10 has started moving. In this case, steps S32 and S36 may be omitted. In this case, instead of the starting limiting area AS1, a stopping area is set to stop the moving industrial vehicle 10. The stopping area may be set in the same way as the starting limiting area AS1.

[0133] ○The control device 31 may increase the width LS1 of the starting restriction area AS1 as the steering angle increases. In this case, if the widths of the forward direction area A6 and the counter-forward direction area A7 are maintained, the width LS2 of the vehicle speed restriction area AS2 may be decreased by the amount by which the width LS1 of the starting restriction area AS1 has been increased. If the widths of the forward direction area A6 and the counter-forward direction area A7 increase as the steering angle increases, the width LS1 of the starting restriction area AS1 may be increased while maintaining the width LS2 of the vehicle speed restriction area AS2.

[0134] ○When the steering angle increases and the widths of the forward-direction area A6 and the anti-forward-direction area A7 increase, the control device 31 may maintain the width LS1 of the starting restriction area AS1 and increase the width LS2 of the vehicle speed restriction area AS2.

[0135] ○The control device 31 may increase the size of either the forward-direction region A6 or the counter-direction region A7 as the steering angle increases. ○In this embodiment, the size of the lateral restriction area AS was changed in three stages: a first turning state, a second turning state, and a third turning state, but the invention is not limited to this. For example, the size of the lateral restriction area AS may be changed more finely by increasing the number of turning states. Alternatively, the number of stages in which the size of the lateral restriction area AS changes may be reduced by eliminating the second and third turning states.

[0136] ○The size of at least one of the forward-direction region A6 and the anti-forward-direction region A7 may be continuously varied according to the steering angle. ○Even when the industrial vehicle 10 is moving straight, a forward-direction area A6 and a reverse-direction area A7 may be set. In this case, the width of the forward-direction area A6 and the width of the reverse-direction area A7 may be smaller than in the first turning state. Even in this case, a starting restriction area AS1 and a vehicle speed restriction area AS2 are set.

[0137] ○The side detection unit can be any sensor capable of detecting the position of an obstacle. For example, the side detection unit may be LiDAR (Light Detection And Ranging) or radar. ○The detection device 56 may detect people from the image using an object detection model. For example, when detecting an obstacle behind, the detection device 56 may detect the position of the obstacle using stereo processing and also detect people from the image by inputting the image into an object detection model.

[0138] Object detection models are generated using machine learning with DNNs (Deep Neural Networks). These models employ algorithms capable of determining object classes on a region-by-region basis. Examples of such machine learning algorithms include YOLO-Pose, SSD (Single Shot Multibox Detector), R-CNN (Regional Convolutional Neural Network), fast R-CNN, or faster R-CNN.

[0139] By setting "person" as the class, the object detection model outputs the probability that an obstacle in the image is a person or not. The detection device 56 can determine from the output of the object detection model whether or not a person is included in the image. If a person is included in the image, the detection device 56 recognizes the position of the person from the position of the detected obstacle using stereo parallax.

[0140] Furthermore, by defining a class for objects other than people, detection of non-human objects can also be performed. ○When detecting obstacles to the side, the detection device 56 may detect people by inputting images acquired from the side cameras 53 and 54 into an object detection model. The detection device 56 inputs the images into an object detection model similar to the modified example described above. This estimates the position of the person and the position of the person's feet in the image. The detection device 56 then calculates the position of the person in the world coordinate system from the installation height, angle, focal length of the side cameras 53 and 54 and the estimated position of the person's feet. Furthermore, the position of people in the rear may also be calculated using the same method as described above, without performing stereo processing. In this case, the stereo camera 52 may be replaced with a monocular camera.

[0141] ○The detection device 56 may be configured to prioritize the detection of either people or non-people when detecting obstacles behind or to the side. For example, in areas where people are prohibited from entering, such as no-entry zones, it may be configured to prioritize the detection of non-people. Also, in areas with frequent pedestrian traffic, it may be configured to prioritize the detection of people.

[0142] ○The industrial vehicle 10 may be an automatically operating vehicle. ○The detection device 56 does not need to detect obstacles behind the vehicle body 11. In this case, the industrial vehicle 10 does not need to be equipped with a stereo camera 52.

[0143] ○The control device 31 does not need to perform acceleration limiting. ○The control device 31 does not need to implement deceleration limits. ○The forklift may be a reach-type forklift. In this case, the direction control unit 36 ​​may also serve as the accelerator control unit 34.

[0144] [Definition] As used herein, the expression "at least one" means "one or more" of the desired options. For example, as used herein, "at least one" means "only one option" or "both of the two options" if there are two options. As another example, as used herein, "at least one" means "only one option" or "a combination of two or more any options" if there are three or more options. [Explanation of Symbols]

[0145] AS1...Starting restriction area, AS2...Vehicle speed restriction area, 10...Industrial vehicle, 11...Vehicle body, 31...Control device, 53, 54...Side camera, which is an example of a side detection unit.

Claims

1. Industrial vehicles, The car body and, A side detection unit that detects obstacles located to the side of the vehicle body, The system includes a control device that sets a stopping area and a vehicle speed limiting area located outside the stopping area on the side of the vehicle body, according to the steering angle and direction of travel of the industrial vehicle. The control device is If the aforementioned obstacle is located within the vehicle speed limit area, the industrial vehicle is permitted to travel up to the set vehicle speed limit. An industrial vehicle that is controlled to stop if the aforementioned obstacle is present in the stopping area.

2. The industrial vehicle according to claim 1, wherein the control device increases the left-right dimensions of the vehicle speed limiting area and the stopping area according to the steering angle.

3. The control device is If the obstacle is located within the vehicle speed limit area when the industrial vehicle is being started, the industrial vehicle shall be permitted to travel up to the upper limit of the vehicle speed. The industrial vehicle according to claim 1, wherein if the obstacle is present in the stopping area when the industrial vehicle is being started, the industrial vehicle is controlled to stop.

4. The industrial vehicle according to claim 1, wherein the control device allows the industrial vehicle to accelerate up to a set upper limit of acceleration when the obstacle is located within the vehicle speed limit area.

5. The industrial vehicle according to claim 1, wherein the side detection unit is a monocular camera.

6. The aforementioned obstacles include persons, The control device is If the person is in the speed-restricted area, the industrial vehicle is permitted to travel up to the upper limit of the vehicle speed. The industrial vehicle according to claim 1, which is controlled to stop the industrial vehicle if the person is present in the stopping area.

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