Industrial vehicles

Abstract

To prevent contact with obstacles located on the opposite side of the direction of travel. [Solution] The industrial vehicle 10 comprises a vehicle body 11 and an obstacle detection unit. The obstacle detection unit comprises one stereo camera, two side cameras, and a detection device. The detection device uses images acquired from the stereo camera to detect obstacles in the rear range behind the vehicle body 11. The detection device uses images acquired from the side cameras to detect obstacles in the lateral range to the sides of the industrial vehicle 10. The control device changes the starting restriction area A according to the direction of travel and steering angle of the industrial vehicle. The control device restricts the starting of the industrial vehicle 10 when an obstacle is located in the starting restriction area A.

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] Depending on the traveling direction and steering angle of the industrial vehicle, there is also a risk that an obstacle existing on the opposite side of the traveling direction will come into contact with the industrial vehicle.

Means for Solving the Problems

[0005] The industrial vehicle that solves the above problems is an industrial vehicle, comprising a vehicle body, a detection unit that detects an obstacle existing around the vehicle body, and a control device that restricts the start of the industrial vehicle when the obstacle detected by the detection unit is located in a start restriction area. The detection unit includes a front detection unit that detects an obstacle in front of the vehicle body, a rear detection unit that detects an obstacle behind the vehicle body, a left detection unit that detects an obstacle on the left side among the sides of the vehicle body, and a right detection unit that detects an obstacle on the right side among the sides of the vehicle body. The control device changes the start restriction area according to the traveling direction and steering angle of the industrial vehicle.

[0006] The control device changes the starting restriction area according to the direction of travel and steering angle of the industrial vehicle. When the industrial vehicle turns, it rotates around the center of rotation. As a result, the part of the industrial vehicle opposite to the direction of travel moves from side to side, which may cause it to come into contact with an obstacle on the opposite side of the direction of travel. By changing the starting restriction area according to the direction of travel and steering angle of the industrial vehicle, the starting restriction area can be set to avoid contact with obstacles on the opposite side of the direction of travel. This reduces the risk of contact with obstacles on the opposite side of the direction of travel.

[0007] With respect to the above-mentioned industrial vehicle, the control device may increase the starting restriction area on the direction of travel side as the steering angle increases. With respect to the above-mentioned industrial vehicle, the control device may reduce the starting restriction area on the opposite side of the direction of travel as the steering angle increases.

[0008] In the case of the above-mentioned industrial vehicle, the right-side detection unit and the left-side detection unit may also serve as the front-side detection unit. In the above-mentioned industrial vehicle, the right-side detection unit and the left-side detection unit may be monocular cameras.

[0009] With respect to the above-mentioned industrial vehicle, the obstacle may include a person, and the control device may restrict the starting of the industrial vehicle if the person is located in the starting restriction area. [Effects of the Invention]

[0010] According to the present invention, contact with obstacles located on the opposite side of the direction of travel can be suppressed. [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]FIG. 4 is a flowchart showing the processes performed by the detection device. [Figure 5] FIG. 5 is a schematic diagram showing the rear range and the side range. [Figure 6] FIG. 6 is a diagram showing the start restriction area when the traveling direction is neutral. [Figure 7] FIG. 7 is a diagram showing the start restriction area when the traveling direction is the reverse direction and the industrial vehicle is in a straight-ahead state. [Figure 8] FIG. 8 is a diagram showing the start restriction area when the traveling direction is the reverse direction and the industrial vehicle is in the first turning state to the left. [Figure 9] FIG. 9 is a diagram showing the start restriction area when the traveling direction is the reverse direction and the industrial vehicle is in the second turning state to the left. [Figure 10] FIG. 10 is a diagram showing the start restriction area when the traveling direction is the reverse direction and the industrial vehicle is in the third turning state to the left. [Figure 11] FIG. 11 is a diagram showing the start restriction area when the traveling direction is the forward direction and the industrial vehicle is in a straight-ahead state. [Figure 12] FIG. 12 is a diagram showing the start restriction area when the traveling direction of the industrial vehicle is the forward direction and the industrial vehicle is in the first turning state to the left. [Figure 13] FIG. 13 is a diagram showing the start restriction area when the traveling direction of the industrial vehicle is the forward direction and the industrial vehicle is in the second turning state to the left. [Figure 14] FIG. 14 is a diagram showing the start restriction area when the traveling direction of the industrial vehicle is the forward direction and the industrial vehicle is in the third turning state to the left. [Figure 15] FIG. 15 is a flowchart showing the start restriction control executed by the control device.

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 cab 16, and a cargo handling 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 cab 16.

[0013] The cargo handling device 20 is provided in front of the driver's cab 16. The cargo handling 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 placed on the forks 22. The lift cylinder 23 is a hydraulic cylinder. The mast 21 moves up and down by the extension 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 cargo handling operation by an operator's operation.

[0014] The industrial vehicle 10 includes a steering wheel 18. The steering wheel 18 is provided in front of the driver's cab 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.

[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-human 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 stereo camera 52 is a rear detection unit that detects obstacles behind the vehicle body 11.

[0041] 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.

[0042] 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 is a left-side detection unit that detects obstacles on the left side of the vehicle body 11. The right-side camera 54 is a right-side detection unit that detects obstacles on the right side of the vehicle body 11. The left-side camera 53 and the right-side camera 54 also function as a forward detection unit that detects obstacles in front of the vehicle body 11. The stereo camera 52 and the side cameras 53 and 54 are detection units that detect obstacles present around the vehicle body 11.

[0043] 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.

[0044] <Departure Restriction Area> The control device 31 performs starting restriction control. Starting restriction control is a control that restricts the starting of the industrial vehicle 10 according to the position of obstacles detected by the obstacle detection unit 51. First, the starting restriction area used in starting restriction control will be explained.

[0045] As shown in Figures 6 to 14, the control device 31 changes the starting restriction 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 starting restriction area A is defined, for example, by the XY coordinates of the world coordinate system.

[0046] The starting restriction area A includes the rear restriction area AR, which is set in the rear range R1. The rear restriction area AR is an area that restricts the starting of the industrial vehicle 10 when an obstacle detected by the image acquired from the stereo camera 52 is located in the rear restriction area AR.

[0047] The starting restriction area A includes the lateral restriction area AS, which is set in the lateral ranges R2 and R3. The lateral restriction area AS is an area that restricts the starting of the industrial vehicle 10 when an obstacle detected by images acquired from the lateral cameras 53 and 54 is located within the lateral restriction area AS.

[0048] <When the direction of travel is neutral> As shown in Figure 6, when the direction of travel is neutral, the rear restriction area AR consists of the central area A1, the left area A2, and the right area A3. When the direction of travel is neutral, the lateral restriction area AS consists of the left area A4 and the right area A5. When the direction of travel is neutral, the shape of the rear restriction area AR and the lateral restriction area AS is the same regardless of the steering angle.

[0049] The central region A1 is the region facing the industrial vehicle 10 in the front-rear direction. The left-right dimension L11 of the central region A1 coincides with the left-right dimension L6 of the industrial vehicle 10. The central region A1 is the region that the industrial vehicle 10 passes through when it is moving straight in the reverse direction.

[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 left-side restricted area A4 and the right-side restricted area A5 are, for example, identical in shape. The left-side restricted area A4 is a rectangular area set along the left edge of the industrial vehicle 10. The right-side restricted area A5 is a rectangular area set along the right edge of the industrial vehicle 10. The front ends of the left-side restricted area A4 and the right-side restricted area A5 are located in front of the tip of the fork 22. The rear ends of the left-side restricted area A4 and the right-side restricted area A5 are located behind the rear end of the vehicle body 11. The left-right dimension L21 of the left-side restricted area A4 is longer than the left-right dimension L12 of the left-side restricted area A2. The left-right dimension L22 of the right-side restricted area A5 is longer than the left-right dimension L13 of the right-side restricted area A3.

[0052] <When the direction of travel is reverse and the industrial vehicle is moving straight ahead> As shown in Figure 7, when the industrial vehicle 10 is moving in the reverse direction and is moving straight, the central area A1 is set as the rear restriction area AR. The lateral restriction area AS is not set. The straight-ahead state is when the steering angle is 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 straight. The 1st angle can be set appropriately, for example, within the range of 3° to 8°.

[0053] <When the direction of travel is reverse and the industrial vehicle is in the first turning position> As shown in Figure 8, when the industrial vehicle 10 is moving in the reverse direction and is in the first turning state, the rear restriction area AR is set as the central area A1 plus 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 first turning state is a state in which the absolute value of the steering angle is greater than the first angle and less than or equal to the second angle. The second angle is an angle greater than the first angle. The second angle can be set appropriately, for example, in the range of 15° to 30°. The first turning state is a state in which 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.

[0054] 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.

[0055] 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 rearward restriction 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 starting restriction area A on the direction of travel side.

[0056] 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 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 starting restriction area A on the opposite side of the direction of travel.

[0057] 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.

[0058] When the industrial vehicle 10 is moving in the reverse direction and is in a first rightward turn, the central area A1 and the right-side area A3 are set as the rearward restriction 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.

[0059] Figure 8 shows the starting restriction area A when the industrial vehicle 10 is in the first left turn position. The starting restriction area A when the industrial vehicle 10 is in the first right turn position is the same shape as the starting restriction area A when the industrial vehicle 10 is in the first left turn position, but reversed horizontally. For this reason, the starting restriction area A when the industrial vehicle 10 is in the first right turn position is not shown.

[0060] <When the direction of travel is reverse and the industrial vehicle is in a second turning position> As shown in Figure 9, when the industrial vehicle 10 is moving in the reverse direction and is in the second turning state, the rear restriction area AR is set as the central area A1 plus 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 set appropriately, 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.

[0061] 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.

[0062] 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 rearward restriction 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 lateral dimension L31 of 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 becomes longer than in the first turning state. This lateral dimension L31 is, for example, the same as the lateral dimension L12 of the left region A2, or the lateral dimension L13 of the right region A3. The size of the anti-direction of travel region A7 set when the industrial vehicle 10 is moving in the reverse direction and is in the second turning state may be the same as the anti-direction of travel region A7 set in the first turning state.

[0063] 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.

[0064] 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 rearward restriction 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.

[0065] Figure 9 shows the starting restriction area A when the industrial vehicle 10 is in the left second turning position. The starting restriction area A when the industrial vehicle 10 is in the right second turning position is the same shape as the starting restriction area A when the industrial vehicle 10 is in the left second turning position, but reversed horizontally. For this reason, the starting restriction area A when the industrial vehicle 10 is in the right second turning position is not shown.

[0066] <When the direction of travel is in reverse, and the industrial vehicle is in a third turning position> As shown in Figure 10, when the industrial vehicle 10 is moving in the reverse direction and is in the third turning state, the rear restriction 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 turning in place.

[0067] 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.

[0068] 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 rearward restriction 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 L32 of the direction of travel region A6 is longer than in the second turning state. For example, the longitudinal dimension L32 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 lateral dimension L33 of the direction of travel region A6 is longer throughout the longitudinal direction than in the first turning state. This lateral dimension L33 is longer than, for example, the lateral dimension L12 of the left side region A2, or the lateral dimension L13 of the right side region A3.

[0069] 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 L34 of the counter-direction region A7 is longer than in the second turning state. For example, the longitudinal dimension L34 of the counter-direction region A7 is longer so that the rear end of the counter-direction region A7 is located behind the front wheels 12 and 13. The lateral dimension L35 of the counter-direction region A7 is longer throughout the longitudinal direction than in the second turning state. This lateral dimension L35 is the same as, for example, the lateral dimension L12 of the left region A2, or the lateral dimension L13 of the right region A3.

[0070] 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.

[0071] 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 rearward restriction 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.

[0072] Figure 10 shows the starting restriction area A when the industrial vehicle 10 is in the left third turn position. The starting restriction area A when the industrial vehicle 10 is in the right third turn position is the same shape as the starting restriction area A when the industrial vehicle 10 is in the left third turn position, but reversed horizontally. For this reason, the starting restriction area A when the industrial vehicle 10 is in the right third turn position is not shown.

[0073] <When the direction of travel is forward and the industrial vehicle is moving straight ahead> As shown in Figure 11, when the industrial vehicle 10 is traveling in the forward direction and is moving straight, the starting restriction area A is not set.

[0074] <When the direction of travel is forward and the industrial vehicle is in the first turning position> As shown in Figure 12, when the industrial vehicle 10 is traveling in the forward direction and is in the first turning state, the rear restriction area AR is not set. The lateral restriction area AS consists of the forward direction area A6 and the opposite direction area A7.

[0075] 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.

[0076] 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.

[0077] 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.

[0078] 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.

[0079] 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.

[0080] Figure 12 shows the starting restriction area A when the industrial vehicle 10 is in the first left turn position. The starting restriction area A when the industrial vehicle 10 is in the first right turn position is the same shape as the starting restriction area A when the industrial vehicle 10 is in the first left turn position, but reversed horizontally. For this reason, the starting restriction area A when the industrial vehicle 10 is in the first right turn position is not shown.

[0081] <When the direction of travel is forward and the industrial vehicle is in the second turning position> As shown in Figure 13, when the industrial vehicle 10 is traveling in the forward direction and is in the second turning state, the rear restriction area AR is not set. The lateral restriction area AS consists of the forward direction area A6 and the opposite direction area A7.

[0082] 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 lateral dimension L41 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. This lateral dimension L41 is, for example, the same as the lateral dimension L12 of the left region A2, or the lateral dimension L13 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 may be the same as the counter-direction of travel region A7 set in the first turning state.

[0083] 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.

[0084] 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.

[0085] Figure 13 shows the starting restriction area A when the industrial vehicle 10 is in the second left turn position. The starting restriction area A when the industrial vehicle 10 is in the second right turn position is the same shape as the starting restriction area A when the industrial vehicle 10 is in the second left turn position, but reversed horizontally. For this reason, the starting restriction area A when the industrial vehicle 10 is in the second right turn position is not shown.

[0086] <When the direction of travel is forward and the industrial vehicle is in a third turning position> As shown in Figure 14, when the industrial vehicle 10 is traveling in the forward direction and is in the third turning state, the rear restriction area AR is not set. The lateral restriction area AS consists of the forward direction area A6 and the opposite direction area A7.

[0087] 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 L42 of the direction of travel region A6 is longer than in the second turning state. For example, the longitudinal dimension L42 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 lateral dimension L43 of the direction of travel region A6 is longer throughout the longitudinal direction than in the first turning state. This lateral dimension L43 is longer than, for example, the lateral dimension L12 of the left side region A2 or the lateral dimension L13 of the right side region A3.

[0088] When the industrial vehicle 10 is traveling in the forward direction and is in the third turning state, the anti-traveling direction region A7 is larger than the anti-traveling direction region A7 set when it is in the second turning state. The longitudinal dimension L44 of the anti-traveling direction region A7 is longer than in the second turning state. For example, the longitudinal dimension L44 of the anti-traveling direction region A7 is longer so that the front end of the anti-traveling direction region A7 is located in front of the front wheels 12 and 13. The lateral dimension L45 of the anti-traveling direction region A7 is longer throughout the longitudinal direction than in the second turning state. This lateral dimension L45 is the same as, for example, the lateral dimension L12 of the left region A2, or the lateral dimension L13 of the right region A3.

[0089] 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.

[0090] 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.

[0091] Figure 14 shows the starting restriction area A when the industrial vehicle 10 is in the left third turn position. The starting restriction area A when the industrial vehicle 10 is in the right third turn position is the same shape as the starting restriction area A when the industrial vehicle 10 is in the left third turn position, but reversed horizontally. For this reason, the starting restriction area A when the industrial vehicle 10 is in the right third turn position is not shown.

[0092] As described above, the larger the steering angle, the larger the forward direction region A6 and the counter-forward direction region A7 become. In this embodiment, the forward direction region A6 and the counter-forward direction region A7 are enlarged 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 region 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 counter-forward direction region A7 becomes larger. The forward direction region A6 is the starting restriction area A on the direction of travel side. The counter-forward direction region A7 is the starting restriction area A on the opposite side of the direction of travel.

[0093] <Starting speed restriction control> The following describes the start-up restriction control. The start-up restriction control is performed repeatedly at a predetermined control cycle, for example, while the industrial vehicle 10 is ignited. The industrial vehicle 10 becomes ready to drive when the ignition is ignited.

[0094] As shown in Figure 15, in step S30, the control device 31 determines whether the accelerator is turned on or not. Whether the accelerator is turned on or not can be determined from the detection result of the accelerator sensor 35. Turning the accelerator on indicates that the accelerator control unit 34 is being operated by the operator of the industrial vehicle 10. If the determination result of step S30 is positive, the control device 31 proceeds to step S31. If the determination result of step S30 is negative, the control device 31 proceeds to step S34.

[0095] In step S31, the control device 31 determines whether the vehicle speed [km / h] of the industrial vehicle 10 is below a threshold. The vehicle speed can be derived using the rotational speed and rotational direction of each of the drive motors 41 provided for each of the front wheels 12 and 13, the gear ratio, the outer diameter of the front wheels 12 and 13, and the steering angle detected by the tire angle sensor 38. The rotational speed and rotational direction of the drive motors 41 can be obtained from the drive control device 43. The gear ratio and the outer diameter of the front wheels 12 and 13 can be stored in the memory unit 33 in advance.

[0096] 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 to account for measurement errors. For example, the threshold is set within the range of 0 [km / h] to 0.5 [km / h]. If the vehicle speed of the industrial vehicle 10 is below the threshold, the industrial vehicle 10 is stopped. If the determination result of step S31 is positive, the control device 31 proceeds to step S32. If the determination result of step S31 is negative, the control device 31 proceeds to step S34.

[0097] In step S32, the control device 31 determines whether or not there is a person in the departure restriction area A. 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 there is a person in the departure restriction area A, which is set according to the direction of travel and steering angle. The departure restriction area A 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 A, it is possible to determine whether or not there is a person in the departure restriction area A. If the result of the determination in step S32 is affirmative, the control device 31 proceeds to step S33. If the result of the determination in step S32 is negative, the control device 31 proceeds to step S34.

[0098] In step S33, the control device 31 implements a start restriction. A start restriction is a state that restricts the industrial vehicle 10 from starting from a stationary state. Starting is when the vehicle speed of the industrial vehicle 10 is increased from below a threshold to above a threshold. The start restriction is implemented, for example, by setting a vehicle speed upper limit. If a start restriction is not implemented, a target vehicle speed is set according to the amount of operation of the accelerator control unit 34, and the vehicle speed of the industrial vehicle 10 is controlled to follow this target vehicle speed. If a vehicle speed upper limit is set, a target vehicle speed exceeding the vehicle speed upper limit cannot be set, so the industrial vehicle 10 is prohibited from driving at a vehicle speed exceeding the vehicle speed upper limit. The start restriction may also be a prohibition of starting. To prohibit starting, the vehicle speed upper limit should be set to 0. The start restriction may also be a prohibition of starting at a vehicle speed exceeding the vehicle speed upper limit by setting a vehicle speed upper limit greater than 0.

[0099] In step S34, the control device 31 does not impose a starting restriction. In this case, the control device 31 starts the industrial vehicle 10 at a vehicle speed corresponding to the amount of operation of the accelerator pedal 34. [Operation of this embodiment] The control device 31 sets the starting restriction area A according to the direction of travel and steering angle. For example, when the industrial vehicle 10 is moving straight in the reverse direction, the starting restriction area A is only the central area A1. When the industrial vehicle 10 is moving straight, the amount of movement of the industrial vehicle 10 in the left and right directions is small, so the lateral restriction area AS is not set. Also, when the direction of travel of the industrial vehicle 10 is in the reverse direction and in the first turning state, in addition to the central area A1, the left side area A2 or the right side area A3 is set as the starting restriction area A according to the steering angle. Furthermore, the direction of travel area A6 and the opposite direction of travel area A7 are set as the starting restriction area A. When the industrial vehicle 10 turns while moving in the reverse direction, the front and rear ends of the vehicle body 11 move in the left and right directions. If the turning direction is left, the rear end of the vehicle body 11 moves to the left and the front end of the vehicle body 11 moves to the right. For this reason, the direction of travel area A6 and the opposite direction of travel area A7 are set along the left and right ends of the industrial vehicle 10.

[0100] By setting up a starting restriction area A in this way, the industrial vehicle 10 will be prevented from starting if there are people in the area where it is expected to pass. On the other hand, the starting will not be restricted if there are people in a different location than where the industrial vehicle 10 is expected to pass. This improves work efficiency.

[0101] Industrial vehicles 10 often change direction while stationary. Therefore, they frequently move forward or backward from a standstill. If industrial vehicle 10 is a forklift, it often reverses after loading and unloading operations are performed while stationary. In the environment in which industrial vehicle 10 is operated, people working around industrial vehicle 10 may approach the stationary industrial vehicle 10. Therefore, there is a high need to restrict the starting of industrial vehicle 10. By restricting the starting of industrial vehicle 10 as in the embodiment, contact between industrial vehicle 10 and obstacles can be appropriately suppressed.

[0102] [Effects of this embodiment] (1) The control device 31 changes the starting restriction area A according to the direction of travel and steering angle of the industrial vehicle 10. When the industrial vehicle 10 turns, the industrial vehicle 10 rotates around the turning center. As a result, the part of the industrial vehicle 10 opposite to the direction of travel moves in the left-right direction, which may cause the industrial vehicle 10 to come into contact with an obstacle on the opposite side of the direction of travel. By changing the starting restriction area A according to the direction of travel and steering angle of the industrial vehicle 10, the starting restriction area A can be set to avoid contact with obstacles on the opposite side of the direction of travel. Specifically, not only the direction of travel area A6 but also the opposite direction of travel area A7 can be set as the starting restriction area A. This makes it possible to suppress contact with obstacles on the opposite side of the direction of travel.

[0103] (2) The control device 31 increases the travel direction region A6 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 travel direction region A6 as the steering angle increases, contact with obstacles in the direction of travel can be suppressed.

[0104] (3) The control device 31 increases the counter-direction area A7 as the steering angle increases. By increasing the counter-direction area A7 as the steering angle increases, contact with obstacles on the opposite side of the direction of travel can be suppressed.

[0105] (4) The left camera 53 and the right camera 54 also serve as the forward detection unit. Therefore, compared to the case where a separate forward detection unit is provided, manufacturing costs can be reduced. In addition, the processing load on the detection device 56 can be reduced.

[0106] (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.

[0107] 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.

[0108] (6) The control device 31 restricts the starting of the industrial vehicle 10 when a person is located in the starting restriction area A. If the obstacle is an object other than a person, the starting of the industrial vehicle 10 is not restricted, thus improving work efficiency. For example, if the starting of the industrial vehicle 10 is restricted by walls surrounding it or by the load L being handled, work efficiency may decrease. Since the starting of the industrial vehicle 10 is not restricted by walls or the load L being handled, work efficiency is improved.

[0109] (7) Even when the direction of travel is neutral, a starting restriction area A is set. If an obstacle is present in starting restriction area A, the alarm unit 55 may issue a warning. By setting a starting restriction area A even when the direction of travel is neutral, the alarm unit 55 can issue a warning even when the direction of travel is neutral.

[0110] 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 restrict the starting of the industrial vehicle 10 if an object other than a person is present in the starting restriction area A.

[0111] 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. That is, one camera may serve as the left-side detection unit, the right-side detection unit, and the front-side detection unit. Furthermore, by enabling the camera to detect obstacles in the rear-side area R1, one camera may serve as the left-side detection unit, the right-side detection unit, the front-side detection unit, and the rear-side detection unit.

[0112] ○The side cameras 53 and 54 may be stereo cameras. ○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.

[0113] ○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.

[0114] ○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. ○The forward detection unit, side detection unit, right-side detection unit, and left-side detection unit can be any sensor capable of detecting the position of an obstacle. For example, at least one of the forward detection unit, side detection unit, right-side detection unit, and left-side detection unit may be LiDAR (Light Detection And Ranging) or radar.

[0115] ○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.

[0116] 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.

[0117] 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.

[0118] 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.

[0119] ○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.

[0120] ○The industrial vehicle 10 may be an automatically operating vehicle. ○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.

[0121] [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]

[0122] A...Starting restriction area, A6...Forward direction area, A7...Non-forward direction area, 10...Industrial vehicle, 11...Vehicle body, 31...Control device, 52...Stereo camera, which is an example of a rearward detection unit, 53...Left camera, which is an example of a left-side detection unit, 54...Right camera, which is an example of a right-side detection unit.

Claims

1. Industrial vehicles, The car body and, A detection unit for detecting obstacles present around the vehicle body, The system includes a control device that restricts the starting of the industrial vehicle when the obstacle detected by the detection unit is located in a starting restriction area, The detection unit is A forward detection unit for detecting the obstacle in front of the vehicle body, A rear detection unit for detecting the obstacle behind the vehicle body, A left-side detection unit that detects the obstacle on the left side of the vehicle body, It includes a right-side detection unit that detects the obstacle on the right side of the side of the vehicle body, The control device changes the starting restriction area according to the direction of travel and steering angle of the industrial vehicle.

2. The control device increases the starting restriction area on the direction of travel side as the steering angle increases, according to claim 1, for the industrial vehicle.

3. The control device increases the starting restriction area on the opposite side of the direction of travel as the steering angle increases, according to claim 1, for the industrial vehicle.

4. The industrial vehicle according to claim 1, wherein the right-side detection unit and the left-side detection unit also serve as the front-side detection unit.

5. The industrial vehicle according to claim 1, wherein the right-side detection unit and the left-side detection unit are monocular cameras.

6. The aforementioned obstacles include persons, The industrial vehicle according to claim 1, wherein the control device restricts the starting of the industrial vehicle when the person is located in the starting restriction area.

Images