JP2022012369A - Industrial vehicle - Google Patents

Abstract

To suppress degradation of workability.SOLUTION: An industrial vehicle includes an obstacle detector and main controller. The obstacle detector includes a sensor and a position detection unit. The position detection unit detects a position of an obstacle in a world coordinate system. When the obstacle exists within a detection area designated in the world coordinate system, the main controller gives the alarm and limits a vehicle speed. The main controller designates the detection range associated with a current position of the industrial vehicle.SELECTED DRAWING: Figure 7

Description

This disclosure relates to industrial vehicles.

The vehicle is equipped with an obstacle detection device for detecting obstacles. The obstacle detection device disclosed in Patent Document 1 includes a stereo camera and a detection unit. The stereo camera is arranged so as to capture the surroundings of the vehicle. The detection unit detects the presence area of the obstacle from the image captured by the stereo camera. When an obstacle is detected by the detection unit, the vehicle speed is limited or an alarm is issued.

Japanese Unexamined Patent Publication No. 2014-164564

Industrial vehicles such as forklifts and towing tractors may work in a narrow area where the industrial vehicle can be driven. When an obstacle detection device is mounted on such an industrial vehicle, the obstacle is likely to appear in the detection range for determining the presence of the obstacle in the image captured by the stereo camera. Then, vehicle speed restrictions and warnings will be issued frequently. As a result, workability is reduced.

An object of the present disclosure is to provide an industrial vehicle capable of suppressing a decrease in workability.

The industrial vehicle that solves the above problems is detected by the sensor, the obstacle position detection unit that detects the position of the obstacle in the coordinate system in the real space from the detection result of the sensor, and the obstacle position detection unit. The control unit that issues at least one of an alarm and a vehicle speed limit when the obstacle exists in the detection range set in the coordinate system in the real space, and the control unit associated with the current position of the industrial vehicle. It is equipped with a detection range setting unit for setting the detection range.

When the obstacle detected by the obstacle position detection unit is in the detection range, at least one of the warning and the vehicle speed limit is performed. Since the detection range is associated with the current position of the industrial vehicle, the detection range is set according to the current position of the industrial vehicle. As a result, it is possible to prevent obstacles from constantly entering the detection range. Since frequent warnings and vehicle speed restrictions are suppressed, deterioration of workability is suppressed.

The industrial vehicle is provided with a position derivation unit for deriving the current position and a storage device for storing a correspondence relationship between a restricted area set in an area where the industrial vehicle is used and the detection range. When the current position derived by the position derivation unit corresponds to the restricted area, the detection range setting unit may set the detection range associated with the restricted area according to the correspondence relationship.

For the industrial vehicle, the position derivation unit may receive the radio signal transmitted by the fixed machine installed in the area and derive the current position from the reception mode of the received radio signal.
For the industrial vehicle, the detection range setting unit may set the detection range so that the detection range becomes wider as the passage width becomes wider.

According to the present invention, deterioration of workability can be suppressed.

The schematic diagram which shows the environment where the industrial vehicle in 1st Embodiment is used. The perspective view of the industrial vehicle in 1st Embodiment. The schematic block diagram of the industrial vehicle in 1st Embodiment. The figure which shows an example of the 1st image taken by a stereo camera. The flowchart which shows the process performed by the position detection apparatus in 1st Embodiment. The schematic diagram which shows the position of the obstacle in the XY plane of the world coordinate system. The flowchart which shows the process performed by the main control unit in 1st Embodiment. The figure which shows the correspondence relationship with the combination of the control area and the state of an industrial vehicle, and the detection range. The schematic diagram which shows the 1st detection range when the industrial vehicle is a running state. The schematic diagram which shows the 2nd detection range when the industrial vehicle is a running state. The schematic diagram which shows the 1st detection range when the industrial vehicle is a start state. The schematic diagram which shows the 2nd detection range when the industrial vehicle is a start state. The schematic diagram which shows the environment where the industrial vehicle in 3rd Embodiment is used.

(First Embodiment)
Hereinafter, the first embodiment of the industrial vehicle will be described.
As shown in FIG. 1, the industrial vehicle 10 is used in a predetermined area A1 of indoors such as a warehouse, a factory, a public facility, and a commercial facility. A plurality of shelves S1, S2, S3, S4, S5 are provided in the area A1. The shelves S1, S2, S3, S4, and S5 are arranged side by side at intervals from each other. Assuming that each of the plurality of shelves S1, S2, S3, S4, S5 is the first shelf S1, the second shelf S2, the third shelf S3, the fourth shelf S4, and the fifth shelf S5, each shelf S1 to S5 is the first shelf. The shelves S1 → the second shelf S2 → the third shelf S3 → the fourth shelf S4 → the fifth shelf S5 are arranged in this order. The distance d1 between the first shelf S1 and the second shelf S2 and the distance d2 between the second shelf S2 and the third shelf S3 are the same as each other. The distance d3 between the third shelf S3 and the fourth shelf S4 and the distance d4 between the fourth shelf S4 and the fifth shelf S5 are the same as each other. The intervals d1 and d2 are shorter than the intervals d3 and d4. The shelves S1 to S5 support the shelf board by, for example, a support, and extend in one direction in a plan view. When the shelves S1 to S5 are viewed in a plan view, it can be said that the dimension in one direction is longer than the direction orthogonal to the one direction. The extending direction of the shelves S1 to S5 and the arranging direction of the shelves S1 to S5 are orthogonal to each other. Between the shelves S1 to S5, there are passages P1, P2, P3, and P4 through which the industrial vehicle 10 can pass. The distance d1, d2, d3, d4 between the shelves S1 to S5 can be said to be the aisle width of the aisles P1, P2, P3, P4. The passage P1 between the first shelf S1 and the second shelf S2 and the passage P2 between the second shelf S2 and the third shelf S3 are referred to as first passages P1 and P2. The passage P3 between the third shelf S3 and the fourth shelf S4 and the passage P4 between the fourth shelf S4 and the fifth shelf S5 are referred to as second passages P3 and P4. The passage width of the first passages P1 and P2 is narrower than the passage width of the second passages P3 and P4.

A truck yard TY, which is a stop position of the truck T, is provided in the area A1. Pillar Pi exists in the truck yard TY. Cargo handling work is performed in the area A1 of the present embodiment. The cargo handling work includes a loading work of placing the load W on the truck T and the shelves S1 to S5, and a loading work of taking the load W from the truck T and the shelves S1 to S5. The industrial vehicle 10 of the present embodiment is a forklift used for cargo handling work.

A plurality of fixed machine WTs are provided in the area A1. The fixed machine WT is provided at a position such as the ceiling of the area A1 that does not hinder the progress of the industrial vehicle 10. The fixed machine WT is provided at a predetermined position and does not move from this position. The fixed machine WT periodically transmits a radio signal. This radio signal includes identification information individually set for each fixed device WT. The radio signal may include position information indicating the position of the fixed machine WT.

As shown in FIG. 2, the industrial vehicle 10 includes a vehicle body 11, two drive wheels 12 arranged at the front lower portion of the vehicle body 11, two steering wheels 14 arranged at the rear lower portion of the vehicle body 11, and a cargo handling device. 20 and. The vehicle body 11 includes a head guard 15 provided above the driver's seat.

The cargo handling device 20 includes a mast 21 erected on the front portion of the vehicle body 11, a pair of forks 22 provided so as to be able to move up and down together with the mast 21, and a lift cylinder 23 for raising and lowering the mast 21. The load W is loaded on the fork 22. The lift cylinder 23 is a hydraulic cylinder. When the mast 21 moves up and down due to the expansion and contraction of the lift cylinder 23, the fork 22 moves up and down accordingly. The industrial vehicle 10 of the present embodiment is operated by an operator to perform a traveling operation and a cargo handling operation.

As shown in FIG. 3, the industrial vehicle 10 has an accelerator pedal 16, a direction lever 17, a main control device 31, an auxiliary storage device 34, an accelerator sensor 35, a direction sensor 36, a positioning device 37, and traveling. The motor 41, the rotation speed sensor 42, the traveling control device 43, the obstacle detection device 51, and the bus 60 are provided.

The main control device 31 includes a processor 32 and a storage unit 33. As the processor 32, for example, a CPU: Central Processing Unit, a GPU: Graphics Processing Unit, and a DSP: Digital Signal Processor are used. The storage unit 33 includes RAM: Random access memory and ROM: Read Only Memory. The storage unit 33 stores a program for operating the industrial vehicle 10. It can be said that the storage unit 33 stores a program code or a command configured to cause the processor 32 to execute the process. The storage unit 33, i.e., a computer-readable medium, includes any available medium accessible by a general purpose or dedicated computer. The main control device 31 may be configured by a hardware circuit such as an ASIC: Application Specific Integrated Circuit or an FPGA: Field Programmable Gate Array. The main control unit 31, which is a processing circuit, may include one or more processors operating according to a computer program, one or more hardware circuits such as ASICs and FPGAs, or a combination thereof.

As the auxiliary storage device 34, for example, a non-volatile storage device such as a hard disk drive, a solid state drive, or an EEPROM: Electrically Erasable Programmable Read Only Memory, which can rewrite data, is used.

The auxiliary storage device 34 stores an environmental map showing a map of the environment in which the industrial vehicle 10 is used. The environmental map is information on the physical structure of the surrounding environment of the industrial vehicle 10, such as the shape and size of the environment in which the industrial vehicle 10 is used. It can be said that the environment map is data in which the environment in which the industrial vehicle 10 is used, that is, the area A1 shown in FIG. 1 is represented by the coordinates in the map coordinate system. The map coordinate system expresses the position related to the physical structure of the environment in which the industrial vehicle 10 is used by the coordinates with respect to the origin. The map coordinate system is a Cartesian coordinate system in which one of the axes orthogonal to each other in the horizontal direction is the X axis and the axis different from the X axis is the Y axis. The map coordinate system may include a Z-axis orthogonal to the X-axis and the Y-axis. It can be said that the environmental map may be a two-dimensional map represented by horizontal coordinates or a three-dimensional map represented by horizontal and vertical coordinates. In the following description, the coordinates in the map coordinate system are referred to as map coordinates.

The accelerator sensor 35 detects the amount of operation of the accelerator pedal 16, that is, the accelerator opening degree. The accelerator sensor 35 outputs an electric signal corresponding to the accelerator opening degree to the main control device 31. The main control device 31 can recognize the accelerator opening degree by the electric signal from the accelerator sensor 35.

The direction sensor 36 detects the operating direction of the direction lever 17 that indicates the traveling direction. The direction sensor 36 detects whether the direction lever 17 is operated in the direction instructing forward movement or the direction lever 17 is operated in the direction instructing reverse movement with reference to neutrality. The direction sensor 36 outputs an electric signal corresponding to the operation direction of the direction lever 17 to the main control device 31. The main control device 31 can recognize the operating direction of the direction lever 17 by an electric signal from the direction sensor 36. The main control device 31 can grasp whether the operator has instructed to move forward, has been instructed to move backward, or has not been instructed to move forward.

The positioning device 37 as the position derivation unit derives the current position of the industrial vehicle 10. The current position of the industrial vehicle 10 is the position of the industrial vehicle 10 in the map coordinate system. The positioning device 37 receives the radio signal transmitted from the fixed machine WT, and derives the current position of the industrial vehicle 10 from the reception mode of the received radio signal. The reception mode includes the reception strength and propagation time of the radio signal. The positioning device 37 derives the current position of the industrial vehicle 10 by converting the reception intensity and the propagation time into a distance.

When the current position of the industrial vehicle 10 is derived by using the reception strength of the radio signal, the positioning device 37 estimates the distance from the fixed device WT to the positioning device 37 based on the reception strength of the radio signal. Here, from the identification information included in the radio signal, the positioning device 37 can determine which of the plurality of fixed machine WTs the received radio signal is transmitted from the fixed machine WT. The positioning device 37 can individually estimate the distance from the fixed device WT for each fixed device WT transmitting the wireless signal. If the correspondence between the map coordinates of each fixed machine WT and the identification information of each fixed machine WT can be grasped, the positioning device 37 can derive the current position of the industrial vehicle 10 by multipoint positioning. The correspondence between the map coordinates of each fixed machine WT and the identification information of each fixed machine WT may be stored in a storage medium included in the positioning device 37 or in a storage unit 33 of the main control device 31. Further, if the map coordinates of the fixed machine WT are included as the position information in the radio signal, the correspondence between the map coordinates of each fixed machine WT and the identification information of each fixed machine WT may not be stored. When deriving the current position of the industrial vehicle 10 using the reception strength of the radio signal, the radio signal includes a radio wave compliant with the Bluetooth (registered trademark) Low Energy standard and a radio wave compliant with the WI-FI (registered trademark) standard. Is used.

When deriving the current position of the industrial vehicle 10 using the propagation time of the radio signal, the positioning device 37 estimates the distance from the fixed device WT to the positioning device 37 based on the propagation time of the radio signal. The propagation time is the time from the transmission of the radio signal by the fixed device WT to the reception of the radio signal by the positioning device 37. Similar to the case of utilizing the reception strength of the radio signal, the positioning device 37 can derive the current position of the industrial vehicle 10 by multipoint positioning. The propagation time may be measured by synchronizing the time between the positioning device 37 and the fixed device WT, or may be measured by using the phase difference of different frequencies. When the current position of the industrial vehicle 10 is derived by using the propagation time of the radio signal, a radio wave of UWB: Ultra Wide Band or a radio wave compliant with the WI-FI standard is used as the radio signal. As described above, the positioning method using the propagation time of the radio signal is called the TOA: time of Arrival method.

As described above, the environmental map of the present embodiment is used to derive the current position of the industrial vehicle 10 from the map coordinates of the fixed machine WT. Therefore, the environment map of the present embodiment does not necessarily have to reflect the map coordinates of the structures such as the shelves S1 to S5.

The traveling motor 41 is a driving device for traveling the industrial vehicle 10. The industrial vehicle 10 travels by rotating the drive wheels 12 by driving the traveling motor 41.
The rotation speed sensor 42 detects the rotation speed of the traveling motor 41. As the rotation speed sensor 42, for example, a rotary encoder can be used. The rotation speed sensor 42 outputs an electric signal corresponding to the rotation speed of the traveling motor 41 to the traveling control device 43.

The travel control device 43 is a motor driver that controls the rotation speed of the travel motor 41. The travel control device 43 can recognize the rotation speed and the rotation direction of the travel motor 41 from the electric signal of the rotation speed sensor 42.

The obstacle detection device 51 includes a stereo camera 52 as a sensor, a position detection device 55 that detects the position of an obstacle from an image captured by the stereo camera 52, and an alarm device 58. As shown in FIG. 1, the stereo camera 52 is arranged on the head guard 15. The stereo camera 52 is arranged so that the road surface on which the industrial vehicle 10 travels can be seen from above the industrial vehicle 10. The stereo camera 52 of the present embodiment images the rear of the industrial vehicle 10. Therefore, the obstacle detected by the position detection device 55 becomes an obstacle behind the industrial vehicle 10. The alarm device 58 and the position detection device 55 may be unitized with the stereo camera 52 and arranged on the head guard 15 together with the stereo camera 52. Further, the alarm device 58 and the position detection device 55 may be arranged at different positions from the head guard 15.

As shown in FIG. 3, the stereo camera 52 includes a first camera 53 and a second camera 54. Examples of the first camera 53 and the second camera 54 include those using a CCD image sensor and a CMOS image sensor. The first camera 53 and the second camera 54 are arranged so that their optical axes are parallel to each other. In the present embodiment, the first camera 53 and the second camera 54 are arranged side by side in the horizontal direction with each other. Assuming that the image captured by the first camera 53 is the first image and the image captured by the second camera 54 is the second image, the same obstacle appears laterally shifted in the first image and the second image. Become. More specifically, when the same obstacle is imaged, the obstacle shown in the first image and the obstacle shown in the second image have the first camera 53 and the second camera 54 in the horizontal pixel [px]. There will be a gap depending on the distance between them. The first image and the second image have the same number of pixels, and for example, an image of 640 × 480 [px] = VGA is used. The first image and the second image are images represented by RGB signals.

The position detection device 55 includes a processor 56 such as a CPU and a GPU, and a storage unit 57 including RAM and ROM. The storage unit 57 stores various programs for detecting obstacles from the image captured by the stereo camera 52. It can be said that the storage unit 57 stores a program code or a command configured to cause the processor 56 to execute the process. The storage 57, i.e., a computer-readable medium, includes any available medium accessible by a general purpose or dedicated computer. The position detection device 55 may be configured by a hardware circuit such as an ASIC or FPGA. The position detection device 55, which is a processing circuit, may include one or more processors operating according to a computer program, one or more hardware circuits such as ASICs and FPGAs, or a combination thereof.

The position detection device 55 detects the position of an obstacle existing around the industrial vehicle 10 by repeating the following obstacle detection process at a predetermined control cycle. The position of the obstacle is the relative position between the industrial vehicle 10 and the obstacle.

In the following description, as an example, an obstacle detection process when the environment shown in FIG. 4 is imaged by the stereo camera 52 will be described. FIG. 4 is a first image I1 obtained by imaging the rear of the industrial vehicle 10. As can be seen from the first image I1, there is an obstacle behind the industrial vehicle 10. Obstacles include humans and non-human objects. For convenience of explanation, the coordinates on the first image I1 in which the obstacle exists are shown by the frame AA, but the frame AA does not exist in the actual first image I1.

As shown in FIG. 5, in step S10, the position detection device 55 acquires an image of the same frame from each of the cameras 53 and 54 of the stereo camera 52.
Next, in step S11, the position detection device 55 acquires a parallax image. The parallax image is an image in which the parallax [px] is associated with the pixels. The parallax is obtained by comparing the first image I1 and the second image and calculating the difference in the number of pixels between the first image I1 and the second image for the same feature point appearing in each image. The feature point is a part that can be recognized as a boundary, such as the edge of an obstacle. The feature points can be detected from the luminance information and the like. The position detection device 55 converts RGB to YCrCb using a RAM that temporarily stores each image. The position detection device 55 may perform distortion correction, edge enhancement processing, and the like. The position detection device 55 performs stereo processing for calculating the parallax by comparing the similarity between each pixel of the first image I1 and each pixel of the second image. As the stereo processing, a method of calculating the parallax for each pixel may be used, or a block matching method of dividing each image into blocks containing a plurality of pixels and calculating the parallax for each block may be used. .. The position detection device 55 acquires a parallax image using the first image I1 as a reference image and the second image as a comparison image. The position detection device 55 extracts the pixels of the second image most similar to each pixel of the first image I1, and the difference between the pixels of the first image I1 and the number of pixels in the horizontal direction most similar to the pixels. Is calculated as the parallax. As a result, it is possible to acquire a parallax image in which parallax is associated with each pixel of the first image I1 which is a reference image. The parallax image does not necessarily require display, and indicates data in which parallax is associated with each pixel in the parallax image. The position detection device 55 may perform a process of removing the parallax on the road surface from the parallax image.

Next, in step S12, the position detection device 55 derives the coordinates of the feature points in the world coordinate system, which is the coordinate system in the real space. First, the position detection device 55 derives the coordinates of the feature points in the camera coordinate system. The camera coordinate system is a coordinate system with the stereo camera 52 as the origin. The camera coordinate system is a three-axis Cartesian coordinate system in which the optical axis is the Z axis and the two axes orthogonal to the optical axis are the X axis and the Y axis, respectively. The coordinates of the feature points in the camera coordinate system can be represented by Z coordinate Zc, X coordinate Xc, and Y coordinate Yc in the camera coordinate system. The Z coordinate Zc, the X coordinate Xc, and the Y coordinate Yc can be derived using the following equations (1) to (3), respectively.

（１）式～（３）式におけるＢは基線長［ｍｍ］、ｆは焦点距離［ｍｍ］、ｄは視差［ｐｘ］である。ｘｐは視差画像中の任意のＸ座標であり、ｘ’は視差画像の中心座標のＸ座標である。ｙｐは視差画像中の任意のＹ座標であり、ｙ’は視差画像の中心座標のＹ座標である。

In equations (1) to (3), B is the baseline length [mm], f is the focal length [mm], and d is the parallax [px]. xp is an arbitrary X coordinate in the parallax image, and x'is the X coordinate of the center coordinate of the parallax image. yp is an arbitrary Y coordinate in the parallax image, and y'is the Y coordinate of the center coordinate of the parallax image.

By setting xx as the X coordinate of the feature point in the parallax image, yp as the Y coordinate of the feature point in the parallax image, and d as the parallax associated with the coordinates of the feature point, the feature point in the camera coordinate system can be used. The coordinates are derived.

Here, in a state where the industrial vehicle 10 is located on a horizontal plane, the axis extending in the vehicle width direction of the industrial vehicle 10 in the horizontal direction is the X axis, and the axis extending in the horizontal direction perpendicular to the X axis is the Y axis. , The 3-axis Cartesian coordinate system in which the axis orthogonal to the X-axis and the Y-axis is the Z-axis is the world coordinate system. The Y-axis of the world coordinate system is an axis extending in the front-rear direction of the industrial vehicle 10, which is the traveling direction of the industrial vehicle 10. The Z axis of the world coordinate system is an axis extending in the vertical direction. The coordinates in the world coordinate system can be represented by X coordinate Xw, Y coordinate Yw and Z coordinate Zw.

The position detection device 55 performs world coordinate conversion that converts camera coordinates into world coordinates using the following equation (4). World coordinates are coordinates in the world coordinate system.

ここで、（４）式におけるＨはワールド座標系におけるステレオカメラ５２の設置高さ［ｍｍ］であり、θは第１カメラ５３及び第２カメラ５４の光軸と、水平面とがなす角＋９０°の角度である。

Here, H in the equation (4) is the installation height [mm] of the stereo camera 52 in the world coordinate system, and θ is the angle + 90 ° between the optical axes of the first camera 53 and the second camera 54 and the horizontal plane. The angle of.

In the present embodiment, the origin of the world coordinate system is a coordinate whose X coordinate Xw and Y coordinate Yw are the positions of the stereo camera 52 and the Z coordinate Zw is the position of the road surface. The position of the stereo camera 52 is, for example, an intermediate position between the lens of the first camera 53 and the lens of the second camera 54.

Of the world coordinates obtained by the world coordinate transformation, the X coordinate Xw indicates the distance from the origin to the feature point in the vehicle width direction of the industrial vehicle 10. The Y coordinate Yw indicates the distance from the origin to the feature point with respect to the traveling direction of the industrial vehicle 10. The Z coordinate Zw indicates the height from the road surface to the feature point. Characteristic points are points that represent a part of the surface of an obstacle. In the figure, the arrow X indicates the X axis of the world coordinate system, the arrow Y indicates the Y axis of the world coordinate system, and the arrow Z indicates the Z axis of the world coordinate system.

Next, in step S13, the position detection device 55 extracts obstacles by clustering the feature points. The position detection device 55 sets a set of feature points that are assumed to represent the same obstacle among the feature points that represent a part of the obstacle as one point cloud, and extracts the point cloud as an obstacle. do. The position detection device 55 performs clustering in which feature points located within a predetermined range are regarded as one point cloud from the world coordinates derived in step S12. The position detection device 55 regards the clustered point cloud as one obstacle. The feature point clustering performed in step S13 can be performed by various methods. That is, the clustering may be performed by any method as long as it can be regarded as an obstacle by forming a plurality of feature points into one point group.

Next, in step S14, the position detection device 55 derives the position of the obstacle in the world coordinate system. The position detection device 55 derives the coordinates of the obstacle in the XY plane of the world coordinate system as the position of the obstacle in the world coordinate system. The position detection device 55 can recognize the world coordinates of an obstacle from the world coordinates of the feature points constituting the clustered point cloud. For example, the X-coordinate Xw, Y-coordinate Yw, and Z-coordinate Zw of a plurality of feature points located at the ends of the clustered point group may be the X-coordinate Xw, Y-coordinate Yw, and Z-coordinate Zw of the obstacle. The X-coordinate Xw, Y-coordinate Yw, and Z-coordinate Zw of the feature point that is the center of the point group may be the X-coordinate Xw, Y-coordinate Yw, and Z-coordinate Zw of the obstacle. That is, the coordinates of the obstacle in the world coordinate system may represent the entire obstacle or may represent one point of the obstacle.

The position detection device 55 projects the X-coordinate Xw, Y-coordinate Yw, and Z-coordinate Zw of the obstacle onto the XY plane of the world coordinate system, so that the X-coordinate Xw and Y-coordinate of the obstacle in the XY plane of the world coordinate system are projected. Derive Yw. That is, the position detecting device 55 derives the X coordinate Xw and the Y coordinate Yw of the obstacle in the horizontal direction by removing the Z coordinate Zw from the X coordinate Xw, the Y coordinate Yw and the Z coordinate Zw of the obstacle. As the position of the obstacle in the world coordinate system, the three-dimensional coordinates represented by the X coordinate Xw, the Y coordinate Yw, and the Z coordinate Zw of the world coordinate system may be derived.

The obstacle O shown in FIG. 6 indicates the position of the obstacle existing in the frame AA shown in the first image I1. By performing the processes of steps S10 to S14, the position of the obstacle O in the world coordinate system can be derived from the first image I1 and the second image. The position detection device 55 functions as an obstacle position detection unit.

The alarm device 58 is a device that gives an alarm to a passenger of the industrial vehicle 10 or a person existing around the industrial vehicle 10. Examples of the alarm device 58 include a buzzer that gives an alarm by sound, a lamp that gives an alarm by light, a combination thereof, and the like. When issuing an alarm to the passenger of the industrial vehicle 10, the display unit provided at a position visible to the passenger may be used as an alarm device, and the alarm may be issued by displaying the alarm on the display unit. In this way, the alarm device 58 can have any configuration.

As shown in FIG. 3, the main control device 31, the travel control device 43, and the obstacle detection device 51 are configured so that information can be acquired from each other by the bus 60. The main control device 31, the driving control device 43, and the obstacle detection device 51 acquire information from each other by communicating according to a communication protocol for a vehicle such as CAN: Controller Area Network or LIN: Local Interconnect Network. Is possible.

The main control device 31 derives the vehicle speed and the traveling direction of the industrial vehicle 10 by acquiring the rotation speed and the rotation direction of the traveling motor 41 from the traveling control device 43. The vehicle speed of the industrial vehicle 10 can be derived by using the rotation speed and rotation direction of the traveling motor 41, the gear ratio, the outer diameter of the drive wheel 12, and the like. The traveling direction of the industrial vehicle 10 is either a forward direction or a reverse direction. The traveling direction of the industrial vehicle 10 can be derived from the rotation direction of the traveling motor 41.

The main control device 31 can operate the alarm device 58 by transmitting an alarm command via the bus 60. More specifically, the obstacle detection device 51 includes an operating unit that activates the alarm device 58, and when the alarm command is received, the operating unit activates the alarm device 58.

In the industrial vehicle 10, an alarm and a vehicle speed limit are performed using the alarm device 58 according to the positional relationship between the current position of the industrial vehicle 10 and the obstacle. The main control device 31 repeatedly performs the following controls in a predetermined control cycle to perform an alarm and limit the vehicle speed.

As shown in FIG. 7, in step S21, the main control device 31 acquires information indicating the current position of the industrial vehicle 10 from the positioning device 37. As a result, the main control device 31 grasps the current position of the industrial vehicle 10.

Next, in step S22, the main control device 31 determines whether or not the current position of the industrial vehicle 10 corresponds to the restricted area. The restricted area is an area set by the location of the area A1. In the example shown in FIG. 1, three restricted areas LA1, LA2, and LA3 are set. The three restricted areas LA1, LA2, LA3 are a first restricted area LA1 including the first passages P1 and P2, a second restricted area LA2 including the second passages P3 and P4, and a third restricted area including a truck yard TY. Includes LA3. The map coordinates of the restricted areas LA1, LA2, and LA3 are stored in the storage unit 33 or the auxiliary storage device 34 of the main control device 31. The main control device 31 is based on the information indicating the current position of the industrial vehicle 10 acquired in step S21 and the map coordinates of the restricted areas LA1, LA2, and LA3 stored in the storage unit 33 or the auxiliary storage device 34. It is possible to determine whether or not the current position of is corresponding to the restricted areas LA1, LA2, LA3. As shown in FIG. 7, when the determination result of step S22 is affirmative, the main control device 31 performs the process of step S23. If the determination result in step S22 is negative, the main control device 31 performs the process of step S24.

In step S23, the main control device 31 sets a detection range corresponding to the restricted areas LA1, LA2, and LA3. In the example shown in FIG. 1, detection range DAs having different sizes are set for each of the restricted areas LA1, LA2, and LA3. The detection range DA is a range for determining whether or not to perform an alarm and vehicle speed limitation. The detection range DA is defined by world coordinates. In the present embodiment, the detection range DA is defined by the X coordinate Xw and the Y coordinate Yw of the world coordinate system, but the detection range DA is defined by the Z coordinate Zw in addition to the X coordinate Xw and the Y coordinate Yw of the world coordinate system. May be done. It can be said that the detection range DA is set in the world coordinate system. The detection range DA is a range extending rearward from the industrial vehicle 10. The detection range DA of the present embodiment gradually widens as the distance from the industrial vehicle 10 rearward, and then becomes a constant width. This is because the horizontal angle of view of the stereo camera 52 limits the range in which obstacles can be detected in the vicinity of the industrial vehicle 10. The area of the detection range DA is the area of the detection range DA in the XY plane of the world coordinate system. The width of the detection range DA is the maximum dimension in the X-axis direction of the world coordinate system. The length of the detection range DA is the maximum dimension in the Y-axis direction of the world coordinate system.

As shown in FIG. 8, the storage unit 33 or the auxiliary storage device 34 of the main control device 31 stores the correspondence between the restricted areas LA1, LA2, LA3 and the detection range DA. More specifically, the storage unit 33 or the auxiliary storage device 34 of the main control device 31 stores world coordinates for defining the detection range DA, and the range represented by the world coordinates is referred to as the detection range DA. Become. Further, in the present embodiment, in addition to the restricted areas LA1, LA2, LA3, the detection range DA is set according to the state of the industrial vehicle 10. That is, it can be said that the detection range DA is set by the combination of the current position of the industrial vehicle 10 and the state of the industrial vehicle 10. The storage unit 33 or the auxiliary storage device 34 in which the correspondence between the restricted areas LA1, LA2, LA3 and the detection range DA is stored functions as a storage device.

Examples of the state of the industrial vehicle 10 include a running state and a starting state. The traveling state is a state in which the industrial vehicle 10 is traveling. The starting state is a state in which the industrial vehicle 10 transitions from a running stop state to a running state. Whether or not the industrial vehicle 10 is in a traveling state can be determined from the vehicle speed calculated by the main control device 31. If the vehicle speed of the industrial vehicle 10 is higher than the threshold value for travel determination, the main control device 31 can determine that the industrial vehicle 10 is in the traveling state. The main control device 31 can determine that the industrial vehicle 10 is in the traveling stopped state if the vehicle speed of the industrial vehicle 10 is equal to or less than the traveling determination threshold value. The travel determination threshold value is set, for example, in the range of 0 [km / h] to 0.5 [km / h]. The starting state is a state on which at least the industrial vehicle 10 is in a traveling stopped state. For example, the traveling stopped state may be set as the starting state, or the traveling stopped state and the state in which the direction lever 17 is instructed to move backward may be set as the starting state. In the following description, the detection range DA associated with the first restricted area LA1 is referred to as the first detection range DA1, and the detection range DA associated with the second restricted area LA2 is referred to as the second detection range DA2 and the third limitation. The detection range DA associated with the area LA3 is referred to as a third detection range DA3.

Taking the first restricted area LA1 and the second restricted area LA2 as examples, the detection range DA set when the industrial vehicle 10 is in a traveling state will be described.
As shown in FIGS. 9 and 10, the width W1 of the first detection range DA1 associated with the first restricted area LA1 is narrower than the passage width of the first passage P1. The width W2 of the second detection range DA2 associated with the second restricted area LA2 is narrower than the passage width of the second passage P3. The width W2 of the second detection range DA2 is wider than the width W1 of the first detection range DA1. When the industrial vehicle 10 is in a traveling state, the length L1 of the first detection range DA1 and the length L2 of the second detection range DA2 are the same. Since the second passage P3 existing in the second restricted area LA2 has a wider passage width than the first passage P1 existing in the first restricted area LA1, the width of the detection range DA1 and DA2 is set wider as the passage width is wider. It can be said that it is.

Taking the first restricted area LA1 and the second restricted area LA2 as examples, the detection range DA set when the industrial vehicle 10 is in the starting state will be described.
As shown in FIGS. 11 and 12, the length L1 of the first detection range DA1 is set when the industrial vehicle 10 places the load W on the shelves S1 to S3 or when the load W is taken from the shelves S1 to S3. The shelves S1 to S3 located behind the 10 are set so as not to enter the first detection range DA1. For example, the length L1 of the first detection range DA1 is set shorter than the value obtained by subtracting the length of the vehicle body 11 from the passage width of the first passage P1. The length L2 of the second detection range DA2 is the shelves S3 to S5 located behind the industrial vehicle 10 when the industrial vehicle 10 places the load W on the shelves S3 to S5 or when the load W is taken from the shelves S3 to S5. Is set not to enter the second detection range DA2. For example, the length L2 of the second detection range DA2 is set shorter than the value obtained by subtracting the length of the vehicle body 11 from the passage width of the second passage P3. The length L2 of the second detection range DA2 is longer than the length L1 of the first detection range DA1. When the industrial vehicle 10 is in the starting state, the width W1 of the first detection range DA1 and the width W2 of the second detection range DA2 are the same. Since the second passage P3 existing in the second restricted area LA2 has a wider passage width than the first passage P1 existing in the first restricted area LA1, the length of the detection range DA1 and DA2 is set longer as the passage width is wider. It can be said that it has been done.

As described above, the detection ranges DA1 and DA2 are set so as to prevent the shelves S1 to S5 from entering the detection ranges DA1 and DA2 regardless of whether the industrial vehicle 10 is in the running state or the starting state. .. When the industrial vehicle 10 is in a traveling state, the wider the passage width, the wider the widths W1 and W2 of the detection ranges DA1 and DA2. When the industrial vehicle 10 is in the starting state, the wider the passage width, the longer the lengths L1 and L2 of the detection ranges DA1 and DA2. As a result, it can be said that the wider the passage width, the wider the detection ranges DA1 and DA2, regardless of whether the industrial vehicle 10 is in the running state or the starting state.

Here, considering the operation when the industrial vehicle 10 performs cargo handling work including loading work and loading work, the industrial vehicle 10 turns after traveling along the passages P1 to P4 along the shelves S1 to S5. Turn to the shelves S1 to S5. Then, the vehicle is stopped in order to carry out cargo handling work. After finishing the cargo handling work, the industrial vehicle 10 is in the starting state. As described above, when the industrial vehicle 10 is in the traveling state, the industrial vehicle 10 often travels in the extending direction of the shelves S1 to S5. When the industrial vehicle 10 is in the starting state, the industrial vehicle 10 finishes the unloading work or the unloading work and faces the shelves S1 to S5 located behind, that is, in the direction orthogonal to the extending direction of the shelves S1 to S5. Often try to progress. The main control device 31 makes different whether the widths W1 and W2 of the detection ranges DA1 and DA2 are changed or the lengths L1 and L2 are changed according to the traveling state and the starting state of the industrial vehicle 10. As a result, if the traveling direction of the industrial vehicle 10 is the extending direction of the shelves S1 to S5, the widths W1 and W2 of the detection ranges DA1 and DA2 are orthogonal to the traveling direction of the industrial vehicle 10 in the extending direction of the shelves S1 to S5. If so, it can be considered that the lengths L1 and L2 of the detection ranges DA1 and DA2 are changed.

The first restricted area LA1 and the second restricted area LA2 have been described as an example, but as shown in FIG. 1, the third detection range DA3 associated with the third restricted area LA3 is also included in the third restricted area LA3. Set. The first restricted area LA1 and the second restricted area LA2 are places where shelves S1 to S5 that can be obstacles are always present in the surroundings. On the other hand, the third restricted area LA3 is a place where it is less likely that an obstacle is always present in the surroundings as compared with the first restricted area LA1 and the second restricted area LA2. Therefore, the third detection range DA3 may be set wider than the detection ranges DA1 and DA2. For example, the length L3 of the third detection range DA3 when the industrial vehicle 10 is in the traveling state may be longer than the length L1 of the first detection range DA1 when the industrial vehicle 10 is in the traveling state. Similarly, the width W3 of the third detection range DA3 when the industrial vehicle 10 is in the traveling state may be wider than the width W1 of the first detection range DA1 when the industrial vehicle 10 is in the traveling state. As described above, the width and length of the detection range DA can be appropriately changed depending on the location. The width and length of the detection range DA differ depending on factors such as whether or not there are structures such as shelves S1 to S5 around, the size of the travelable area of the industrial vehicle 10, and the traffic volume of people and vehicles. You can set the value. As shown in FIG. 7, when the main control device 31 finishes the process of step S23, the main control device 31 performs the process of step S25. By performing the process of step S23, the main control device 31 functions as a detection range setting unit.

In step S24, the main control device 31 sets a default detection range DA. The default detection range DA is a detection range set when the current position of the industrial vehicle 10 does not correspond to the restricted areas LA1, LA2, and LA3. The default detection range DA can be arbitrarily set by the administrator of the industrial vehicle 10. Similar to the detection ranges DA1, DA2, DA3 associated with the restricted areas LA1, LA2, LA3, the default detection range DA may vary in size depending on the state of the industrial vehicle 10. When the main control device 31 finishes the process of step S24, the main control device 31 performs the process of step S25.

In step S25, the main control device 31 determines whether or not an obstacle exists in the detection range DA. By acquiring the world coordinates of the obstacle from the position detection device 55, the main control device 31 can grasp the positional relationship between the obstacle existing around the industrial vehicle 10 and the industrial vehicle 10. The main control device 31 determines whether or not an obstacle exists in the detection range DA based on the world coordinates of the obstacle and the detection range DA set in step S23 or step S24. If the obstacle is located straddling the inside and outside of the detection range DA, it may be determined that the obstacle exists in the detection range DA, or the obstacle is in the detection range DA. It may be determined that it does not exist.

As shown in FIG. 6, a case where the position of the obstacle O in the world coordinate system is detected will be described as an example. In the example shown in FIG. 6, there are two obstacles O in the detection range DA. Therefore, the main control device 31 determines that the obstacle O exists in the detection range DA. As shown in FIG. 7, when the determination result of step S25 is affirmative, the main control device 31 performs the process of step S26. If the determination result in step S25 is negative, the main control device 31 performs the process of step S27.

In step S26, the main control device 31 gives an alarm and limits the vehicle speed. The main control device 31 gives an alarm by activating the alarm device 58. Further, the main control device 31 sets a vehicle speed upper limit value and limits the vehicle speed by preventing the vehicle speed from exceeding the vehicle speed upper limit value. The vehicle speed upper limit is set to a value lower than the maximum reachable speed of the industrial vehicle 10. The vehicle speed upper limit value includes 0 [km / h]. That is, the vehicle speed limit includes the prohibition of traveling of the industrial vehicle 10.

The warning and vehicle speed limit may be changed according to the distance to the obstacle. For example, the main control device 31 may make the alarm stronger as the distance from the obstacle is closer. Increasing the warning means making it easier for the passengers of the industrial vehicle 10 and the people around the industrial vehicle 10 to recognize the approach of the industrial vehicle 10. If the alarm device 58 gives an alarm by sound, the sound may be louder as the distance from the obstacle is closer, and if the alarm device 58 gives an alarm by blinking light, the blinking speed may be increased. It may be faster. The main control device 31 may set the vehicle speed upper limit value lower as the distance from the obstacle is closer. By performing the processes of steps S25 and S26, the main control device 31 functions as a control unit.

In step S27, the main control device 31 cancels the warning and the vehicle speed limit. More specifically, the main control device 31 cancels the warning and the vehicle speed limit if the warning and the vehicle speed limit have been performed by the processing in the past control cycle, and if the warning and the vehicle speed limit have not been performed, this state. To maintain. While the obstacle is present in the detection range DA, the warning and the vehicle speed limit are performed by continuously affirming step S25. When there are no obstacles in the detection range DA, the warning and the vehicle speed limit are canceled by negating step S25.

The obstacle detection process by the position detection device 55 may be performed only when the industrial vehicle 10 is moving backward or when the industrial vehicle 10 starts backward. That is, the obstacle detection process may not be performed when the industrial vehicle 10 is moving forward or when the industrial vehicle 10 starts forward. It can be determined from the detection result of the direction sensor 36 and the rotation direction of the traveling motor 41 that the industrial vehicle 10 is moving backward. It can be determined from the detection result of the direction sensor 36 that the industrial vehicle 10 starts backward. Similarly, the warning and the vehicle speed limit may be given only when the industrial vehicle 10 is moving backward or when the industrial vehicle 10 starts backward. That is, the warning and the vehicle speed limit may not be performed when the industrial vehicle 10 is moving forward or when the industrial vehicle 10 starts forward. Obstacle detection processing may be performed regardless of the traveling direction of the industrial vehicle 10, and the warning and the vehicle speed limit may be performed only when the industrial vehicle 10 is moving backward or when the industrial vehicle 10 starts backward. When the position detection device 55 detects an obstacle existing behind the industrial vehicle 10 as in the present embodiment, at least the warning and the vehicle speed limit are performed when the traveling direction of the industrial vehicle 10 is behind. Just do it.

The operation of the first embodiment will be described.
The main control device 31 sets a detection range DA associated with the current position of the industrial vehicle 10. The main control device 31 gives an alarm and limits the vehicle speed when an obstacle detected by the position detection device 55 exists in the detection range DA. On the other hand, when the obstacle detected by the position detection device 55 does not exist in the detection range DA, the main control device 31 issues an alarm and limits the vehicle speed even if an obstacle exists outside the detection range DA. Not performed. It can be said that the detection range DA limits the range in which the warning and the vehicle speed are limited.

If the detection range DA is excessively wide, warnings and vehicle speed restrictions are frequently performed depending on the position of the industrial vehicle 10. For example, assuming that the second detection range DA2 is always set regardless of the position of the industrial vehicle 10, when the industrial vehicle 10 is traveling in the first passages P1 and P2, the second detection range DA2 is always set. There is a risk that shelves S1 to S3 will enter. If an alarm and a vehicle speed limit are always given while traveling in the first passages P1 and P2, the workability of the industrial vehicle 10 will deteriorate and the workability of the person working in the first passages P1 and P2 will be reduced. It causes a decline. Further, when the warning and the vehicle speed limit are always performed by the shelves S1 to S3 entering the second detection range DA2, the warning and the vehicle speed limitation are continued regardless of whether or not there is an obstacle obstructing the progress in the first passages P1 and P2. Then, an alarm and a vehicle speed limit will be given. As a result, even if an obstacle exists in the first passages P1 and P2, the passenger of the industrial vehicle 10 may not notice the existence of the obstacle. The industrial vehicle 10 may inevitably approach structures such as shelves S1 to S5 that may be obstacles due to the cargo handling work. Therefore, if the detection range DA is excessively widened as described above, there is a possibility that the structure will always enter the detection range DA, and the warning and the vehicle speed limit may be frequently performed to reduce the workability. If the detection range DA is excessively narrowed, the warning and the vehicle speed limitation due to the detection of the structure as an obstacle can be suppressed, but the obstacle that hinders the progress of the industrial vehicle 10 is difficult to enter the detection range DA. Therefore, the timing at which the warning and the vehicle speed limit are performed may be delayed.

In the present embodiment, the detection range DA is set according to the current position of the industrial vehicle 10. The detection range DA is set so as to prevent structures such as shelves S1 to S5 existing in the restricted areas LA1, LA2, and LA3 from always entering the detection range DA. As a result, it is possible to prevent an obstacle from constantly entering the detection range DA.

The effect of the first embodiment will be described.
(1-1) By setting the detection range DA according to the current position of the industrial vehicle 10, it is possible to prevent an obstacle from always entering the detection range DA. Since frequent warnings and vehicle speed restrictions are suppressed, deterioration of workability is suppressed.

(1-2) The main control device 31 determines whether or not the current position of the industrial vehicle 10 derived by the positioning device 37 corresponds to the restricted areas LA1, LA2, and LA3. When the current position of the industrial vehicle 10 corresponds to the restricted areas LA1, LA2, LA3, the main control device 31 sets the detection ranges DA1, DA2, DA3 associated with the restricted areas LA1, LA2, LA3. There is. It is also conceivable to provide a marker in the area A1 and set the detection range DA by reading this marker. In this case, it takes time and effort to provide the marker in the area A1. Further, it is necessary to provide a device for reading the marker on the industrial vehicle 10 and arrange the marker at a position where the device can read the marker, which causes restrictions on the arrangement. On the other hand, the positioning device 37 can derive the current position of the industrial vehicle 10 without reading the marker. Therefore, it is unlikely that the trouble of providing the marker in the area A1 and the restriction on the arrangement will occur. When using the positioning device 37 that utilizes the reception mode of the wireless signal, it is necessary to provide the fixed device WT in the area A1, but if the positioning device 37 can receive the wireless signal, the position of the fixed device WT is free. .. Therefore, the fixed machine WT has less restrictions on placement than the marker. Further, the fixed machine WT may be arranged as many as the positioning device 37 can perform multi-point positioning, and the time and effort for arranging the fixed machine WT is less than that of the marker.

(1-3) The positioning device 37 derives the current position of the industrial vehicle 10 according to the reception mode of the radio signal transmitted from the fixed machine WT. Therefore, the current position of the industrial vehicle 10 can be derived even indoors. GNSS: Since the current position of the industrial vehicle 10 can be derived even indoors where positioning cannot be performed using the Global Navigation Satellite System, detection according to the current position even for the industrial vehicle 10 used indoors. The range DA can be set.

(1-4) The main control device 31 sets the detection range DA so that the detection range DA becomes wider as the passage width is wider. When the detection range DA is constant, the wider the passage width, the more likely it is that a portion not included in the detection range DA, that is, a blind spot will occur. By widening the detection range DA as the passage width is wider, it is possible to suppress the occurrence of blind spots.

(1-5) If the traveling direction of the industrial vehicle 10 is the direction in which the shelves S1 to S5 extend, the width of the detection range DA is detected. The length of each range DA is changed. When the industrial vehicle 10 is traveling in the extending direction of the shelves S1 to S5, the shelves S1 to S5 are located in the width direction of the detection range DA, so the width of the detection range DA is adjusted to the detection range DA. It is preferable to be able to detect obstacles existing in the passages P1 to P4 while suppressing the entry of the shelves S1 to S5. When the traveling direction of the industrial vehicle 10 is orthogonal to the extending direction of the shelves S1 to S5, the shelves S1 to S5 are located in the length direction of the detection range DA, so the length of the detection range DA is adjusted. It is preferable to be able to detect obstacles existing in the passages P1 to P4 while suppressing the entry of the shelves S1 to S5 into the detection range DA. By changing the detection range DA as described above, an appropriate detection range DA according to the situation of the industrial vehicle 10 is set.

(Second Embodiment)
Hereinafter, the second embodiment of the industrial vehicle will be described. The description of the same parts as those of the first embodiment will be omitted, and the differences from the first embodiment will be described.

In the first embodiment, the current position of the industrial vehicle 10 is derived by using the positioning device 37, whereas in the second embodiment, the current position of the industrial vehicle 10 is derived by self-position estimation by the main control device 31. do. The industrial vehicle 10 of the second embodiment does not have to be provided with the positioning device 37.

The main control device 31 performs self-position estimation for estimating self-position and posture. The self-position is the current position of the industrial vehicle 10. The posture is the orientation of the industrial vehicle 10 in the map coordinate system. More specifically, the posture is the inclination of the industrial vehicle 10 with respect to the X-axis or the Y-axis of the map coordinate system. In the present embodiment, the self-position estimation is performed by matching landmarks using at least the stereo camera 52. The main control device 31 estimates its own position by matching the map coordinates of the obstacle detected by the position detection device 55 with the landmarks on the environmental map. In the second embodiment, it is necessary to store the map coordinates of the structure existing in the area A1 as a landmark as an environmental map. As the structure used as a landmark, a structure whose position does not change with the passage of time or whose position does not easily change is used. In the area A1 shown in FIG. 1, for example, the map coordinates of the shelves S1 to S5 and the pillar Pi can be used as landmarks. Further, as the landmark, the map coordinates of the wall may be used. The environmental map may be created by mapping by SLAM: Simultaneous Localization and Mapping, or may be created in advance if the physical structure of the area A1 is known in advance.

In addition to the method using landmarks, self-position estimation may be performed by combining odometry that estimates self-movement amount using the rotation speed of the traveling motor 41. As the rotation speed of the traveling motor 41, the detection result of the rotation speed sensor 42 can be used. The detection result of the rotation speed sensor 42 can be acquired from the travel control device 43 via the bus 60.

The main control device 31 derives the current position of the industrial vehicle 10 by self-position estimation, and sets the detection range DA associated with the current position of the industrial vehicle 10. The detection range DA can be set by the same method as in the first embodiment. In the second embodiment, the main control device 31 functions as a position derivation unit.

Further, in the second embodiment, since the posture of the industrial vehicle 10 can be estimated, the detection range DA according to the posture of the industrial vehicle 10 is set in addition to the current position of the industrial vehicle 10 and the situation of the industrial vehicle 10. You may. For example, the detection range DA can be changed according to the presence of an obstacle existing in the direction in which the industrial vehicle 10 faces. If a known structure such as shelves S1 to S5 exists in the direction facing the industrial vehicle 10, the detection range DA may be set so that the structure does not enter the detection range DA. Further, if the industrial vehicle 10 faces the extending direction of the shelves S1 to S5, the width of the detection range DA is changed, and if the direction of the industrial vehicle 10 is orthogonal to the extending direction of the shelves S1 to S5, the detection range DA is changed. The length of may be changed.

The effect of the second embodiment will be described.
(2-1) The main control device 31 derives the current position of the industrial vehicle 10 by self-position estimation. Self-position estimation can be performed using a stereo camera 52 provided for detecting an obstacle. Therefore, the positioning device 37 can be omitted.

(2-2) The attitude of the industrial vehicle 10 can be derived by performing self-position estimation. Therefore, the detection range DA can be set according to the posture of the industrial vehicle 10.
(Third Embodiment)
Hereinafter, a third embodiment of the industrial vehicle will be described. The description of the same parts as those of the first embodiment will be omitted, and the differences from the first embodiment will be described.

As shown in FIG. 13, markers M1, M2, and M3 are provided in the area A1. The markers M1, M2, and M3 include an AR marker, a QR code (registered trademark), which is an identification image including a plurality of rectangles or dots arranged two-dimensionally, a one-dimensional code including a barcode, and a color code. Various markers such as a multidimensional code including can be used. The markers M1, M2, and M3 are provided in each of the first restricted area LA1, the second restricted area LA2, and the third restricted area LA3. The marker M1 provided in the first restricted area LA1 is the first marker M1, the marker M2 provided in the second restricted area LA2 is the second marker M2, and the marker M3 provided in the third restricted area LA3 is the third marker M3. And. The first marker M1, the second marker M2, and the third marker M3 have different patterns such as shapes and colors. In other words, the information associated with each of the first marker M1, the second marker M2, and the third marker M3 is different.

The industrial vehicle 10 includes an image pickup device for reading the markers M1, M2, and M3. As the image pickup device, the stereo camera 52 may also be used, or an image pickup device for reading the markers M1, M2, and M3 may be provided separately from the stereo camera 52.

The markers M1, M2, and M3 are arranged at positions that can be read by the image pickup apparatus. Since the angle of view of the image pickup apparatus is predetermined, the positions of the markers M1, M2, and M3 are determined in consideration of this angle of view. The first marker M1 when the industrial vehicle 10 is located in the first restricted area LA1, the second marker M2 when the industrial vehicle 10 is located in the second restricted area LA2, and the industrial vehicle 10 are the third. The positions of the markers M1, M2, and M3 are determined so that the third marker M3 is imaged when the marker is located in the restricted area LA3. The markers M1, M2 and M3 are attached to structures located in the restricted areas LA1, LA2 and LA3 such as shelves S1 to S5, walls, pillars Pi and floors.

The main control device 31 reads information from the markers M1, M2, and M3 imaged by the image pickup device by the image recognition function. Examples of the information associated with the markers M1, M2, and M3 include position information or information indicating the detection range DA. Explaining the first marker M1 as an example, when the position information is associated with the first marker M1, the information indicating that it is the first restricted area LA1 is associated with the position information. The main control device 31 recognizes that the current position of the industrial vehicle 10 is the first restricted area LA1 from the position information associated with the first marker M1, and sets the first detection range DA1. When the information indicating the detection range DA is associated with the first marker M1, the information indicating the first detection range DA1 is associated with the first marker M1. The information indicating the first detection range DA1 may be the world coordinates defining the first detection range DA1. The main control device 31 sets the first detection range DA1 from the information indicating the detection range DA associated with the first marker M1.

As described above, since the first marker M1 is arranged so as to be imaged by the image pickup device when the industrial vehicle 10 is located in the first restricted area LA1, the first marker M1 is imaged by the image pickup device. If so, it can be said that the industrial vehicle 10 is located in the first restricted area LA1. That is, the first detection range DA1 associated with the first restricted area LA1 is set without deriving the current position of the industrial vehicle 10. When the first detection range DA1 is set by reading the first marker M1, it can be said that it is not necessary to store the environmental map. Further, the industrial vehicle 10 does not have to be equipped with the positioning device 37. Further, when the information indicating the detection range DA is associated with the first marker M1, the restricted areas LA1, LA2, LA3 and the detection range DA1, DA2 are associated with the storage unit 33 and the auxiliary storage device 34 of the main control device 31. , It is not necessary to memorize the correspondence with DA3. As an example, the first marker M1 has been described, but the same can be said for the second marker M2 and the third marker M3.

Depending on the arrangement position of the markers M1, M2 and M3, the markers M1, M2 and M3 may be imaged by the image pickup device even from outside the restricted areas LA1, LA2 and LA3. In this case, although the current position of the industrial vehicle 10 is outside the restricted areas LA1, LA2, LA3, the detection ranges DA1, DA2 associated with the restricted areas LA1, LA2, LA3 in which the markers M1, M2, M3 are arranged are arranged. , DA3 may be set. When the size of the markers M1, M2 and M3 imaged by the image pickup device, that is, the number of pixels of the markers M1, M2 and M3 is less than a predetermined threshold value, the main control device 31 causes the markers M1, M2 and M2. The information associated with M3 may not be read. As a result, even though the current position of the industrial vehicle 10 is outside the restricted areas LA1, LA2, LA3, the detection ranges DA1, DA2 associated with the restricted areas LA1, LA2, LA3 in which the markers M1, M2, M3 are arranged are arranged. , DA3 can be suppressed from being set.

The effect of the third embodiment will be described.
(3-1) The main control device 31 sets the detection range DA by reading the information associated with the markers M1, M2, and M3 by image recognition. By setting the detection range DA using the markers M1, M2, and M3, the detection range DA associated with the current position of the industrial vehicle 10 can be set without deriving the current position of the industrial vehicle 10. Can be done.

Each embodiment can be modified and implemented as follows. Each embodiment and the following modifications can be implemented in combination with each other within a technically consistent range.
○ In each embodiment, the detection ranges DA1, DA2, and DA3 associated with the restricted areas LA1, LA2, and LA3 can be arbitrarily set by the manager of the industrial vehicle 10. For example, the detection range DA may be widened in a place where moving objects including vehicles and people frequently pass while there are few structures such as shelves S1 to S5.

-In each embodiment, the length L1 of the first detection range DA1 and the length L2 of the second detection range DA2 when the industrial vehicle 10 is in a traveling state may be different. Similarly, the width W1 of the first detection range DA1 and the width W2 of the second detection range DA2 when the industrial vehicle 10 is in the starting state may be different.

○ In each embodiment, the state of the industrial vehicle 10 may include a cargo handling work state. When the industrial vehicle 10 is in the cargo handling work state, the main control device 31 may set a detection range DA different from the traveling state and the starting state. For example, the main control device 31 may have a longer detection range DA when the industrial vehicle 10 is in the cargo handling work state than when the industrial vehicle 10 is in the traveling state.

○ In each embodiment, the detection range DA may be any as long as it is associated with the current position of the industrial vehicle 10, and the width of the detection range DA may not change depending on the state of the industrial vehicle 10.

○ In each embodiment, the detection range DA may have any shape. For example, the detection range DA may be a range extending from the industrial vehicle 10 in a circular shape or a fan shape.
○ In each embodiment, the main control device 31 may increase the length of the detection range DA as the speed of the industrial vehicle 10 increases.

○ In each embodiment, the detection range DA may be set by the position detection device 55. In this case, the position detection device 55 may consider that the obstacle existing outside the detection range DA is not an obstacle. That is, the position detection device 55 does not have to transmit the world coordinates of the obstacle outside the detection range DA to the main control device 31 even when the obstacle exists outside the detection range DA.

○ The positioning device 37 of the first embodiment may derive the current position of the industrial vehicle 10 by using the incident angle of the radio signal. The positioning device 37 derives the incident angle of the radio signal transmitted from the fixed device WT. The positioning device 37 derives the current position of the industrial vehicle 10 from the incident angles of the plurality of radio signals. It can be said that the reception mode of the radio signal includes the incident angle of the radio signal. In this case, as the wireless signal, a radio wave or a sound wave conforming to the WI-FI standard can be used. As described above, the positioning method using the incident angle of the radio signal is called the AOA: Angle of Arrival method. The positioning device 37 may be of a method other than the above as long as it uses a wireless signal such as a radio wave arrival time difference method.

○ In the first embodiment, the current position of the industrial vehicle 10 may be derived by a positioning device provided in the area A1. In this case, the industrial vehicle 10 includes a radio transmission unit that transmits a radio signal to the fixed machine WT provided in the area A1. The positioning device provided in the area A1 derives the current position of the industrial vehicle 10 from the reception mode of the radio signal in the fixed machine WT. In other words, the relationship between the transmission and reception of the radio signal is reversed between the fixed machine WT and the industrial vehicle 10. The positioning device provided in the area A1 by the same method as that described in the first embodiment and the above-described modification can derive the current position of the industrial vehicle 10. In this case, the positioning device provided in the area A1 transmits information indicating the current position of the industrial vehicle 10 to the industrial vehicle 10. As a result, the main control device 31 can recognize the current position of the industrial vehicle 10.

○ In the first embodiment, the positioning device 37 may perform positioning using GNSS. GNSS includes GPS, GLONASS, IRNSS, and QZSS. The positioning device 37 receives the satellite signal transmitted from the GNSS satellite and derives the current position of the industrial vehicle 10 from the received satellite signal. In this case, the industrial vehicle 10 is used outdoors. Further, by using the positioning device 37 of the first embodiment and the positioning device 37 for positioning using GNSS together, the current position of the industrial vehicle 10 can be derived regardless of whether it is indoors or outdoors. You may do so.

○ In the second embodiment, the self-position estimation may be performed by using dead reckoning using an acceleration sensor or a gyro sensor, or may be performed by using the above-mentioned GNSS. Further, the self-position estimation may be performed by combining these self-position estimations with the self-position estimation described in the second embodiment.

○ In the first embodiment, instead of deriving the current position of the industrial vehicle 10 by the positioning device 37, the detection range DA may be set from the color of the road surface. There may be a plurality of road surface colors in the environment in which the industrial vehicle 10 is used. For example, in a factory, in a walking zone or a dangerous zone where people pass, the road surface color may be used to express what kind of place the position is by making the road surface color different from other positions. The walking zone is painted in blue to recognize that it is a walking zone, and the danger zone is a zebra zone in which yellow and black are alternately arranged to recognize that it is a danger zone. In some cases. In this way, in an environment where the road surface color is associated with the position, it can be said that the detection range DA corresponding to the current position of the industrial vehicle 10 is set by setting the detection range DA in association with the road surface color. .. For example, since a person is often present in the walking zone, the size of the detection range DA may be set so that the person can be detected quickly.

In order to detect the color of the road surface, the industrial vehicle 10 includes an image pickup device arranged to image the road surface. Examples of the image pickup apparatus include a CCD image sensor and a device using a CMOS image sensor. The storage unit 33 or the auxiliary storage device 34 of the main control device 31 stores a correspondence relationship in which the color and the detection range DA are associated with each other. The main control device 31 detects the color of the road surface from the image captured by the image pickup device. The main control device 31 sets a detection range DA associated with the color of the road surface.

○ In each embodiment, the position detection device 55 may perform a process of determining whether the detected obstacle is a human or a non-human obstacle after the process of step S14. Whether or not an obstacle is a person can be determined by various methods. For example, the position detection device 55 determines whether or not an obstacle is a person by performing a person detection process on an image captured by one of the two cameras 53 and 54 of the stereo camera 52. .. The position detection device 55 converts the coordinates of the obstacle in the world coordinate system obtained in step S14 into the camera coordinates, and converts the camera coordinates into the coordinates of the image captured by the cameras 53 and 54. For example, the position detection device 55 converts the coordinates of an obstacle in the world coordinate system into the coordinates of the first image. The position detection device 55 performs a person detection process on the coordinates of the obstacle in the first image. The human detection process is performed using, for example, feature quantity extraction and a human determination device that has been machine-learned in advance. Examples of the feature amount extraction include a method of extracting the feature amount of a local region in an image such as HOG: Histogram of Oriented Gradients feature amount and Haar-Like feature amount. As the human judgment device, for example, a machine learning using a supervised learning model is used. As a supervised learning model, for example, a support vector machine, a neural network, naive bays, deep learning, a decision tree, or the like can be adopted. As the teacher data used for machine learning, image-specific components such as human shape elements and appearance elements extracted from the image are used. Examples of the shape element include the size and contour of a person. Examples of the appearance element include light source information, texture information, camera information, and the like. The light source information includes information on reflectance, shading, and the like. The texture information includes color information and the like. The camera information includes information on image quality, resolution, angle of view, and the like.

In this way, when determining whether or not the obstacle is a person, the processing performed by the main control device 31 may be changed depending on whether or not the obstacle is a person. When the obstacle existing in the detection range DA is a person, the main control device 31 may make the alarm stronger than when the obstacle is not a person. When the obstacle existing in the detection range DA is a person, the main control device 31 may set the vehicle speed upper limit value lower than when the obstacle is not a person.

○ In each embodiment, the main control device 31 may issue either an alarm or a vehicle speed limit when an obstacle exists in the detection range DA. If the main control device 31 does not give an alarm, the industrial vehicle 10 may not be equipped with the alarm device 58.

○ In each embodiment, the obstacle detection device 51 may detect the position of an obstacle existing in the forward direction in the traveling direction of the industrial vehicle 10. In this case, the stereo camera 52 is arranged so as to face the front of the industrial vehicle 10. When the obstacle detection device 51 detects the position of an obstacle existing in the forward direction of the industrial vehicle 10, the detection range DA extends forward from the industrial vehicle 10. Further, when the traveling direction of the industrial vehicle 10 is the forward direction, the warning and the vehicle speed limitation are performed.

The obstacle detection device 51 may be capable of detecting the position of an obstacle existing in both the reverse direction and the forward direction in the traveling direction of the industrial vehicle 10. In this case, one obstacle detection device 51 may be able to detect obstacles existing in both the reverse direction and the forward direction of the traveling direction of the industrial vehicle 10, or may be combined with the obstacle detection device 51 for the forward direction. , An obstacle detection device 51 for the reverse direction may be provided. When detecting the position of an obstacle existing in both the reverse direction and the forward direction in the traveling direction of the industrial vehicle 10, if the traveling direction of the industrial vehicle 10 is the forward direction, an alarm is given by the obstacle existing in the forward direction. And the vehicle speed will be limited. When the traveling direction of the industrial vehicle 10 is the reverse direction, the warning and the vehicle speed limitation are performed by the obstacle existing in the reverse direction.

○ In each embodiment, the obstacle detection device 51 may use a ToF: Time of Flight camera, LIDAR: Laser Imaging Detection and Ranging, millimeter-wave radar, or the like as the sensor instead of the stereo camera 52. The TOF camera includes a camera and a light source that irradiates light, and derives the distance in the depth direction for each pixel of the image captured by the camera from the time until the reflected light of the light emitted from the light source is received. It is a thing. LIDAR is a rangefinder that can recognize the surrounding environment by irradiating a laser while changing the irradiation angle and receiving the reflected light reflected from the part hit by the laser. The millimeter wave radar is capable of recognizing the surrounding environment by irradiating the surroundings with radio waves in a predetermined frequency band. The stereo camera 52, the ToF camera, the LIDAR, and the millimeter wave radar are sensors capable of deriving three-dimensional coordinates in the world coordinate system. The obstacle detection device 51 preferably includes a sensor capable of measuring three-dimensional coordinates. The obstacle detection device 51 may include a combination of a plurality of sensors such as a stereo camera 52 and LIDAR.

Instead of the stereo camera 52, the obstacle detection device 51 can derive the coordinates of a two-axis Cartesian coordinate system in which one of the horizontal directions is the X-axis and the axis in the direction orthogonal to the X-axis is the Y-axis. It may be equipped with a sensor. That is, as the sensor, a sensor that can derive two-dimensional coordinates that are the horizontal coordinates of the obstacle may be used. As this type of sensor, for example, a two-dimensional LIDAR that irradiates a laser while changing the irradiation angle in the horizontal direction can be used.

Further, the sensor may be a combination of each of the above-mentioned sensors and a monocular camera. In this case, the detection result of the sensor may be used to detect the world coordinates of the obstacle, and the image captured by the monocular camera may be used to determine whether or not the obstacle detected by the sensor is a person.

○ In each embodiment, the stereo camera 52 may include three or more cameras.
○ In each embodiment, the world coordinate system is not limited to the orthogonal coordinate system and may be a polar coordinate system.

○ In each embodiment, the conversion from camera coordinates to world coordinates may be performed by table data. The table data is table data in which the combination of the Y coordinate Yc and the Z coordinate Zc corresponds to the Y coordinate Yw, and the table data in which the combination of the Y coordinate Yc and the Z coordinate Zc corresponds to the Z coordinate Zw. By storing these table data in the storage unit 57 of the position detection device 55, the Y coordinate Yw and the Z coordinate Zw in the world coordinate system can be obtained from the Y coordinate Yc and the Z coordinate Zc in the camera coordinate system. .. In the embodiment, since the X coordinate Xc in the camera coordinate system and the X coordinate Xw in the world coordinate system match, the table data for obtaining the X coordinate Xw is not stored.

○ In each embodiment, the alarm device 58 may be provided by a device other than the obstacle detection device 51.
○ In each embodiment, the alarm device 58 may be directly operated by the main control device 31.

○ In each embodiment, the industrial vehicle 10 may be driven by an engine which is a driving device. In this case, the travel control device 43 is a device that controls the fuel injection amount to the engine and the like.

-In each embodiment, the industrial vehicle 10 may be an automatically operated vehicle, or may be a vehicle that can switch between an automatic operation and a manual operation.
○ In each embodiment, the industrial vehicle 10 may be remotely controlled by an operator who is not on the industrial vehicle 10.

-In each embodiment, the industrial vehicle 10 may include one device having a function of the main control device 31 and a function of the position detection device 55. That is, the functions of the main control device 31 and the functions of the position detection device 55 may be integrated into one device.

-In each embodiment, the obstacle position detection unit may be composed of a plurality of devices.
○ In each embodiment, the main control device 31, the travel control device 43, and the obstacle detection device 51 may be configured so that information on each other can be acquired by a radio.

○ In each embodiment, the information stored in the auxiliary storage device 34 may be stored in a storage medium other than the auxiliary storage device 34, such as the storage unit 33 of the main control device 31 or the storage unit 57 of the position detection device 55. good. In this case, the industrial vehicle 10 does not have to be provided with the auxiliary storage device 34.

○ In each embodiment, the industrial vehicle 10 may be any such as a towing vehicle used for transporting a load, an order picker used for picking work, a towing tractor, and the like.

A1 ... Area, DA ... Detection range, LA1, LA2, LA3 ... Restricted area, WT ... Fixed machine, 10 ... Industrial vehicle, 31 ... Control unit, Detection range setting unit, Main control device that functions as a position derivation unit, 33 ... A storage unit as a storage device, 34 ... an auxiliary storage device as a storage device, 37 ... a positioning device as a position derivation unit, 52 ... a stereo camera as a sensor, 55 ... a position detection device as an obstacle position detection unit.

Claims (4)

With the sensor
An obstacle position detection unit that detects the position of an obstacle in a coordinate system in real space from the detection result of the sensor, and an obstacle position detection unit.
A control unit that issues at least one of an alarm and a vehicle speed limit when the obstacle detected by the obstacle position detection unit exists in the detection range set in the coordinate system in the real space.
An industrial vehicle including a detection range setting unit for setting the detection range associated with the current position of the industrial vehicle. The position derivation unit that derives the current position and
A storage device for storing a correspondence relationship between a restricted area set in an area where the industrial vehicle is used and the detection range is provided.
The first aspect of claim 1 is that when the current position derived by the position derivation unit corresponds to the restricted area, the detection range setting unit sets the detection range associated with the restricted area by the correspondence relationship. Industrial vehicle. The industrial vehicle according to claim 2, wherein the position derivation unit receives a radio signal transmitted by a fixed machine installed in the area, and derives the current position from the reception mode of the received radio signal. The industrial vehicle according to any one of claims 1 to 3, wherein the detection range setting unit sets the detection range so that the wider the passage width is, the wider the detection range is.

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