belt monitoring system

Abstract

This system provides a belt monitoring system that prevents delays in cargo handling operations while ensuring the safety of drivers. [Solution] The belt monitoring system S comprises a shooting unit 12, a belt wearing determination unit 24, and a speed change unit 29. The shooting unit 12 photographs the driver's seat of the forklift and generates a seat image, and the belt wearing determination unit 24 determines whether or not the driver is wearing a safety belt based on the seat image. If the belt wearing determination unit 24 determines that the driver is not wearing a safety belt, the speed change unit 29 changes the operating speed of the forklift according to each operation of the forklift.

Description

Technical Field

[0001] The present invention relates to a belt wearing monitoring system for a forklift.

Background Art

[0002] When a forklift lifts and transports a load, there is a risk of tipping over or rolling over. If the forklift rolls over, the driver may be thrown out of the vehicle and may be crushed under the forklift. Therefore, in order to prevent being thrown out of the vehicle, the driver needs to wear a safety belt provided on the driver's seat.

[0003] However, since the driver may frequently get on and off the forklift during work, the driver may forget to wear the safety belt or may deliberately not wear it. Therefore, in order to prevent such forgetting to wear the safety belt, a system for detecting forgetting to wear the safety belt has been developed. However, it is not easy to detect whether the safety belt is worn or not. Therefore, for example, the wearing detection device disclosed in Patent Document 1 provides an identification member that can be recognized only when worn on a seat belt (safety belt), and when the identification member is recognized from a camera image, it is specified that the seat belt is worn. And, for example, when the seat belt is not worn, the vehicle is made unable to run, thereby protecting the safety of the driver.

[0004] By the way, a forklift not only runs but also performs other operations, and the driver's operations are also different from those of a driver of a general passenger car. Also, if the vehicle is uniformly stopped from running when the safety belt is not worn, the cargo handling work may be delayed.

Prior Art Documents

Patent Documents

[0005]

Patent Document 1

Summary of the Invention

[0006] Therefore, the problem that the present invention aims to solve is to provide a belt monitoring system that can prevent delays in cargo handling operations while protecting the safety of the driver. [Means for solving the problem]

[0007] To solve the above problems, the belt monitoring system according to the present invention is A camera unit that photographs the driver's seat of a forklift and generates an image of the seat, A seating determination unit that determines whether or not the driver is wearing a seat belt based on a seat image, The system includes a speed change unit that, if it is determined that the driver is not wearing a safety belt, changes the operating speed of the forklift according to each operation of the forklift.

[0008] The above belt monitoring system is preferably, The speed control unit will reduce the fork lifting speed if it detects that the driver is not wearing a safety belt while the forklift is raising or lowering its forks.

[0009] The above belt monitoring system is preferably, If the speed control unit detects that the driver is not wearing a safety belt, it reduces the maximum lifting speed of the forks to between 50 and 150 mm per second.

[0010] The above belt monitoring system is preferably, The speed control unit stops raising the forks if it determines that the driver is not wearing a safety belt when the fork height is higher than a predetermined height and the forklift is loaded.

[0011] The above belt monitoring system is preferably, The speed control unit will stop raising the forks if it determines that the driver is not wearing a safety belt while the forklift is moving and raising / lowering its forks, and the forklift is loaded with a load.

[0012] The above belt monitoring system is preferably, If the speed control unit detects that the driver is not wearing a seatbelt, it will reduce the forklift's speed.

[0013] The above belt monitoring system is preferably, The system further includes a stopping mechanism that stops the forklift's movement if it is determined that the driver is not wearing a safety belt while the forklift is moving or raising / lowering its forks, the forks are higher than a predetermined height, and the forklift is loaded with a load.

[0014] The above belt monitoring system is preferably, The speed control unit will stop the forklift from rising if it detects that the driver is not wearing a safety belt while the forklift is moving or raising / lowering its forks.

[0015] The above belt monitoring system is preferably, The fitting determination unit, The system has a pre-trained model that uses multiple seat images as input data and output data indicating whether or not a seat belt is worn. When a seat image is input, it outputs a score indicating whether or not a seat belt is worn. Based on the score output by the trained model, it is determined whether or not the driver is wearing a seatbelt.

[0016] The above belt monitoring system is preferably, The forklift has a switch to turn the forklift drive ON / OFF. The safety belt has a fitting sensor that detects when the safety belt is being worn. The wearing determination unit determines that the driver is not wearing the safety belt only when the switch is ON and the wearing sensor does not detect the wearing of the safety belt.

[0017] The belt monitoring system preferably has a wearing determination unit that has been pre-trained by machine learning using teacher data with a plurality of seat images as input data and the presence or absence of wearing the safety belt as output data, and outputs a score indicating the presence or absence of wearing the safety belt when a seat image is input, and a first learned model, has been pre-trained by machine learning using teacher data with a plurality of consecutive seat images as input data and whether the safety belt is being removed as output data, and outputs a score indicating whether the safety belt is being removed when a plurality of consecutive seat images are input, and a second learned model, and determines whether the driver is wearing the safety belt based on each score output by the first and second learned models.

[0018] The belt monitoring system preferably further includes a notification unit that notifies the driver that the safety belt is not worn when it is determined that the driver is not wearing the safety belt.

[0019] The belt monitoring system preferably further includes an image storage unit that stores seat images at a predetermined time before and after the time when it is determined that the driver is not wearing the safety belt when it is determined that the driver is not wearing the safety belt.

[0020] To solve the above problems, a forklift according to the present invention includes the above belt monitoring system.

[0021] To solve the above problems, a belt monitoring program according to the present invention is a belt monitoring program used for a belt monitoring system having a photographing unit that photographs the driver's seat and generates a seat image and a computer, and causes the computer to A seating determination unit that determines whether or not the driver is wearing a seat belt based on a seat image, If it is determined that the driver is not wearing a safety belt, the speed change unit is activated to change the operating speed of each forklift operation according to the forklift's movements. [Effects of the Invention]

[0022] The belt monitoring system according to the present invention can prevent delays in cargo handling operations while protecting the safety of drivers. [Brief explanation of the drawing]

[0023] [Figure 1] A is a side view showing a forklift according to one embodiment of the present invention, and B is an enlarged view of the safety belt portion. [Figure 2] A is a side view showing another forklift according to one embodiment of the present invention, and B is an enlarged view of the safety belt portion. [Figure 3] This is a block diagram of the belt monitoring system. [Figure 4] This diagram shows the operation of the fitting determination unit. [Figure 5] This table shows the control method for the speed change mechanism during each operation of the forklift when it is determined that the driver is not wearing a safety belt. [Figure 6] This is a flowchart illustrating the operation of the belt monitoring system. [Modes for carrying out the invention]

[0024] Hereinafter, an embodiment of the belt monitoring system and a forklift equipped with the belt monitoring system of the present invention will be described with reference to the attached figures. In the figures, the X axis represents the front-to-back direction, the Y axis represents the left-to-right direction, and the Z axis represents the up-and-down direction.

[0025] <Forklift Configuration> Figure 1A is a side view showing a counterbalanced forklift 1 according to this embodiment, and Figure 2A is a side view showing a picking forklift 1 according to this embodiment. The belt monitoring system S according to the present invention can be used with various types of forklifts. The forklift 1 shown in Figures 1 and 2 is an example of such forklifts. Therefore, the forklift 1 in this embodiment is a battery-powered counterbalanced forklift and a battery-powered picking forklift, but this is merely an example, and the forklift in the present invention is not limited to these forklifts 1. Figure 3 is a block diagram of the belt monitoring system S according to this embodiment.

[0026] As shown in Figures 1A and 2A, the forklift 1 comprises multiple wheels 2, a body 3, left and right masts 4, left and right forks 5, pillars 7, head guards 8, a driver's seat 9, a drive unit 11, an imaging unit 12, and a speaker 14.

[0027] The vehicle body 3 is positioned above the wheels 2, and the left and right masts 4 are positioned in front of the vehicle body 3. The forks 5 of the counterbalanced forklift 1 are connected to the masts 4 and are configured to move up and down along the masts 4. On the other hand, the forks 5 of the picking forklift 1 are connected to the masts 4 via the driver's cab 10 and are configured to move up and down along the masts 4 together with the driver's cab 10.

[0028] The driver's seat 9 of the counterbalanced forklift 1 is located on the vehicle body 3, while the driver's seat 9 of the picking forklift 1 is located on the driver's cab 10. The driver H sits or stands in the driver's seat 9 and operates the forklift 1 by operating the levers, pedals, and other controls located in the driver's seat 9. The head guard 8 is supported by multiple pillars 7 and is located above the driver's seat 9.

[0029] The drive unit 11 is composed of drive components such as a motor and is connected to either the front or rear wheel 2. The drive unit 11 drives the connected wheel 2 to move the forklift 1 forward or backward. When the present invention is applied to an engine-powered forklift, the drive unit 11 is composed of drive components including an engine.

[0030] The camera unit 12 of the counterbalanced forklift 1 is positioned on the right front pillar 7 and is configured to photograph the driver's seat 9. The camera unit 12 of the picking forklift 1 is positioned on the underside of the head guard 8 and is configured to photograph the driver's seat 9. However, the locations of these camera units 12 are merely examples, and the camera unit 12 is not limited to these locations. The camera unit 12 photographs the driver's seat 9 and generates a seat image SG. In this embodiment, the camera unit 12 consists of one camera. However, this is merely an example, and the camera unit 12 may consist of, for example, multiple cameras.

[0031] Speaker 14 is located on the head guard 8 and emits an alert sound to notify and warn the driver H that the seatbelt SB is not fastened. The location of speaker 14 is merely an example and is not limited to this. The alert sound may be a specific voice or a beep.

[0032] As shown in Figure 3, the forklift 1 further includes a lifting unit 16, a brake 18, and a control unit 20.

[0033] The lifting section 16 has a lift cylinder that extends and retracts by hydraulic pressure from a hydraulic fluid. The lifting section 16 is connected to the mast 4, and the extension and retraction of the lift cylinder extends and retracts the mast 4 and raises and lowers the fork 5. The lifting section 16 may also be composed of an actuator that is operated by electricity.

[0034] The brake 18 is positioned on the wheel 2 and stops the rotation of the wheel 2. The type of brake 18 is not particularly limited.

[0035] The control unit 20 is comprised of a computer located inside the vehicle body 3. The control unit 20 includes an arithmetic unit, a storage device, and memory. The storage device stores a belt monitoring program that causes the computer to execute as an action detection unit 22, a mounting determination unit 24, a height detection unit 26, a load presence / absence detection unit 28, a speed change unit 29, a stop unit 32, and a notification unit 34, which will be described later.

[0036] <Functional Configuration of the Belt Monitoring System> Next, the functional configuration of the belt monitoring system S will be described. As shown in Figure 3, the control unit 20 includes an action detection unit 22, an attachment determination unit 24, a height detection unit 26, a load presence / absence detection unit 28, a speed change unit 29, a stop unit 32, and a notification unit 34.

[0037] The motion detection unit 22 detects the operation of the forklift 1. The operation of the forklift 1 includes moving forward and backward, and raising and lowering the forks 5. The method of motion detection by the motion detection unit 22 is not particularly limited. For example, the motion detection unit 22 may detect the operation of the forklift 1 by reading signals from the control unit operated by the driver H, or it may be configured to directly detect the operation of the drive unit 11 and the lifting unit 16.

[0038] The fitting determination unit 24 determines whether or not the driver H is wearing the safety belt SB based on the seat image SG. As shown in Figures 1B and 2B, the forklift 1 is equipped with a safety belt SB. As shown in Figure 1B, the safety belt SB of the counterbalanced forklift 1 is provided on the seat, and the driver H wears the safety belt SB while seated. On the other hand, as shown in Figure 2B, the safety belt SB of the picking forklift 1 has a belt that the driver H wears around their waist, a hook F that locks onto a ring on the belt, and a cable C with one end fixed to the head guard 8 and the other end fixed to the hook F. In this way, the safety belt SB of the picking forklift 1 prevents the driver H from falling from the driver's seat 9 (driver's cab 10). The fitting of the safety belt SB of the picking forklift 1 is conditional on the driver H wearing the safety belt SB and the hook F being connected to the safety belt SB.

[0039] As shown in Figure 4, the fitting determination unit 24 may have, for example, a first pre-trained model 240 that has been pre-trained. The first pre-trained model 240 is pre-trained using training data that takes multiple seat images SG as input data and outputs whether or not a safety belt SB is worn as output data, and is trained to output whether or not a safety belt SB is worn when a seat image SG is input. The seat image SG includes images where the safety belt SB is removed and images where the safety belt SB is worn. The fitting determination unit 24 determines whether or not a safety belt SB is worn from the output result of the first pre-trained model 240. The machine learning of the first pre-trained model 240 may use, for example, deep learning, and the learning method is not particularly limited.

[0040] Incidentally, the driver H of the picking forklift 1 sometimes detaches the hook F from the safety belt SB before operating the forklift 1. However, since driver H may change the orientation of his body, the camera may not be able to capture the hook F depending on the orientation of driver H's body. As a result, it is difficult to determine from the seat image SG whether or not the hook F is detached from the safety belt SB. Therefore, the first trained model 240 may output a score (hereinafter referred to as the "wearing score") indicating whether or not the safety belt SB is being worn. In this case, the wearing determination unit 24 determines whether or not driver H is wearing the safety belt SB depending on whether or not the wearing score output from the first trained model 240 is higher than a predetermined score.

[0041] As shown in Figure 4, the fitting determination unit 24 may further include a second trained model 241. The second trained model 241 is pre-trained using training data that takes multiple consecutive seat images SG as input data and outputs whether or not the person is trying to unfasten the safety belt SB as output data. When multiple consecutive seat images SG are input, it is configured to output a score (hereinafter referred to as the "unfastening score") indicating whether or not the person is trying to unfasten the safety belt SB. The machine learning of the second trained model 241 may, for example, utilize deep learning, and the learning method is not particularly limited.

[0042] The fitting determination unit 24 determines that driver H is not wearing a seatbelt if the removal score output by the second trained model 241 is above a predetermined score, and the fitting score output by the first trained model 240 thereafter is below the predetermined score. The first trained model 240 is machine-trained to output a score below the predetermined score if the hook F is not included in the seat image SG, or if it is unclear from the seat image SG whether the cable C extends from the part of the seatbelt SB (i.e., whether the cable C is free). As a result, the fitting determination unit 24 can appropriately determine whether the seatbelt SB is worn even when the hook F is not included in the seat image SG and it is unclear whether driver H is wearing the seatbelt SB.

[0043] The height detection unit 26 detects the height of the fork 5. The height detection method of the height detection unit 26 is not particularly limited. The forklift 1 may further include a sensor for detecting the height of the fork 5, and the height detection unit 26 may use this sensor to detect the height of the fork 5. The sensor for detecting the height of the fork 5 may be, for example, a distance sensor, a position sensor, or an optical encoder. In this case, the distance sensor may be ultrasonic or laser, and detects the height of the fork 5 by emitting ultrasonic waves or lasers to detect the distance from the bottom surface of the fork 5 to the ground. The position sensor is placed on the lift cylinder of the lifting unit 16 and detects the extension and retraction state of the lift cylinder to detect the height of the fork 5. The optical encoder is attached to a shaft (not shown) that rotates as the fork 5 moves up and down, and detects the height of the fork 5 by counting the number of rotations of the shaft.

[0044] The load presence / absence detection unit 28 detects whether or not the forklift 1 is carrying a load W (hereinafter referred to as "presence or absence of load W"). The method by which the load presence / absence detection unit 28 detects the presence or absence of load W is not particularly limited. For example, the forklift 1 may further have a sensor that detects the hydraulic pressure of the hydraulic fluid in the lifting section 16, and the load presence / absence detection unit 28 may detect the presence or absence of load W based on the value detected by this sensor.

[0045] When the speed control unit 29 determines that the driver H is not wearing a safety belt SB, it controls the lifting unit 16 and the drive unit 11 according to each operation of the forklift 1 to change the operating speed of the forklift 1. For example, as shown in the table in Figure 5, the speed control unit 29 may reduce the travel speed or the lifting speed of the forks 5 based on each operation of the forklift 1, the height of the load W, and the presence or absence of the load W. In this way, the speed control unit 29 can prevent delays in cargo handling operations while protecting the safety of the driver H. In addition, under predetermined conditions of the forklift 1, the speed control unit 29 may set the maximum travel speed to 0 km / h, effectively stopping travel, or set the maximum lifting speed to 0 mm / second, effectively stopping both lifting and lowering, or either of them. In this way, the speed control unit 29 can reliably prevent accidents involving the forklift 1 and reliably protect the safety of the driver H.

[0046] The table in Figure 5 shows the control method of the speed change unit 29 during each operation of the forklift 1 when it is determined that the driver H is not wearing the safety belt SB. As shown in the table in Figure 5, in this embodiment, the speed change unit 29 is configured to reduce the travel speed when it is determined that the driver H is not wearing the safety belt SB while the forklift 1 is traveling. The speed change unit 29 may, for example, reduce the maximum travel speed to between 0 km / h and 3 km / h. In this way, the speed change unit 29 can suppress the occurrence or scale of accidents caused by the operation of the forklift 1.

[0047] In this embodiment, the speed change unit 29 is configured to reduce the lifting speed when the height of the load W (i.e., the height of the forks 5) is below a predetermined height (when it is "low" in the table in Figure 5) and it is determined that the driver H is not wearing a safety belt SB. This allows the speed change unit 29 to prevent accidents such as the forklift 1 tipping over. The speed change unit 29 of the forklift 1 may, for example, reduce the lifting speed to between 50 and 150 mm per second. The predetermined height may be, for example, 1 m from the ground or the height of the driver H's line of sight.

[0048] In this embodiment, when the forks 5 are being raised or lowered, if the height of the forks 5 is above a predetermined height (when it is "high" in the table in Figure 5) and the forklift 1 is loaded with a load W, and the speed change unit 29 determines that the driver H is not wearing a safety belt SB, it sets the maximum upward speed of the forks 5 to 0 mm per second to stop the ascent and also decelerates the downward speed of the forks 5. This allows the speed change unit 29 to prevent the load W from falling. On the other hand, when the forks 5 are being raised or lowered, if the height of the forks 5 is above a predetermined height and the driver H is determined not to be wearing a safety belt SB, but the speed change unit 29 does not stop the ascent, but decelerates the upward speed of the forks 5 if the forklift 1 is not loaded with a load W. This is because if there is no load W loaded, the load W will not fall.

[0049] In this embodiment, when the forks 5 are being raised and lowered while the forks 5 are moving, and the height of the forks 5 is above a predetermined height, and the forklift 1 is loaded with a load W, if the speed change unit 29 determines that the driver H is not wearing a safety belt SB, it stops the raising and moving of the forks 5 and reduces the lowering speed of the forks 5. This allows the speed change unit 29 to prevent the load W from falling.

[0050] Furthermore, when the forks 5 are being raised or lowered while the forks are moving, if the height of the forks 5 is above a predetermined height, and the forklift 1 is not loaded with a load W, and the speed change unit 29 determines that the driver H is not wearing a safety belt SB, it will stop the forks 5 from rising and will also reduce the travel speed and the lowering speed of the forks 5. In this way, the speed change unit 29 can prevent accidents such as the forks 5 coming into contact with an obstacle while the forklift 1 is moving and causing the forklift 1 to tip over.

[0051] Furthermore, when the forks 5 are being raised and lowered while the vehicle is in motion, if the height of the forks 5 is below a predetermined height, and the speed change unit 29 determines that the driver H is not wearing a safety belt SB, it will reduce the travel speed and the lifting / lowering speed of the forks 5, regardless of whether or not there is a load W loaded. This is based on the fact that, because the height of the forks 5 is low, reducing the lifting / lowering speed and travel speed can prevent the load W from falling or the forks 5 from colliding with anything.

[0052] When the speed change unit 29 sets the maximum speed of the forklift 1 to 0 km / h, the stopping unit 32 controls the brake 18 to ensure that the forklift 1 comes to a complete stop.

[0053] If the notification unit 34 determines that driver H is not wearing a safety belt SB, it will notify and warn driver H via the speaker 14 that the safety belt SB is not being worn. The content of the notification may be changed according to the operation of each forklift 1.

[0054] <Flowchart of the belt monitoring system> Next, referring to Figure 6, we will explain the operation of the belt monitoring system S again.

[0055] (1) The belt monitoring system S captures the driver's seat 9 with the camera unit 12 and generates a seat image SG (see S(step)1 in Figure 6).

[0056] (2) Next, the seatbelt monitoring system S determines whether the driver H is wearing the seatbelt SB based on the seat image SG (see S2 in Figure 6).

[0057] (3) Next, the belt monitoring system S detects whether the forklift 1 is operating using the motion detection unit 22. If the forklift 1 is operating (Yes in S3 of Figure 6) and is only moving (Yes in S4 of Figure 6), the system S reduces the speed of the forklift 1 (see S5 of Figure 6). If the forklift 1 is not operating, the belt monitoring system S does nothing (returns to S1 of Figure 6).

[0058] (4) When the forklift 1 is only moving up and down (No. in S4, Figure 6; Yes in S6, Figure 6), and a load W is loaded and the height of the forks 5 is high (Yes in S7, Figure 6), the belt monitoring system S stops the forks 5 from rising and reduces the downward speed of the forks 5 (see S8, Figure 6). On the other hand, when the forklift 1 is only moving up and down (No. in S4, Figure 6; Yes in S6, Figure 6), and the height of the forks 5 is low (No. in S7, Figure 6), the belt monitoring system S reduces the upward speed of the forks 5 (see S9, Figure 6).

[0059] (5) When the forklift 1 is operating (Yes in S3 of Figure 6), and is moving while raising and lowering the forks 5 (No in S4 of Figure 6, No in S6 of Figure 6), and the height of the forks 5 is above a predetermined height (Yes in S10 of Figure 6), and a load W is loaded (Yes in S11 of Figure 6), the belt monitoring system S stops the raising and moving of the forks 5 and reduces the lowering speed of the forks 5 (see S12 of Figure 6). On the other hand, if the forklift 1 is not loaded with a load W (No in S11 of Figure 6), the belt monitoring system S stops the raising of the forks 5 and reduces the travel speed and the lowering speed of the forks 5 (see S13 of Figure 6).

[0060] (6) Furthermore, the belt monitoring system S reduces the travel speed and the lifting speed of the forks 5 when the forklift 1 is operating (Yes in S3 of Figure 6), and when the forks 5 are being raised and lowered while the forklift is moving (No in S4 of Figure 6, No in S6 of Figure 6), and when the height of the forks 5 is less than a predetermined height (No in S10 of Figure 6), regardless of whether or not a load W is loaded.

[0061] The belt monitoring system S performs the above operations based on the movement of the forklift 1, the height of the forks 5, and the presence or absence of load W, thereby preventing delays in cargo handling operations while protecting the safety of the driver H.

[0062] Furthermore, the belt monitoring system S can appropriately determine whether or not a safety belt SB is being worn because the belt wearing determination unit 24 has previously learned the relationship between the seat image SG and whether or not a safety belt SB is being worn through machine learning.

[0063] Although one embodiment of the belt monitoring system and forklift equipped with the belt monitoring system of the present invention has been described above, the present invention is not limited to the above embodiment. For example, the belt monitoring system and forklift according to the present invention may be implemented by the following modifications or by appropriately combining the following modifications.

[0064] <Variation> The safety belt SB may have a known wearing sensor that can detect when it is being worn. In this case, the wearing determination unit 24 may determine whether or not the driver H is wearing the safety belt SB based on the detection result of this sensor and the seat image SG. This allows the wearing determination unit 24 to more appropriately determine whether or not the safety belt SB is being worn.

[0065] The forklift 1 may further include a switch (e.g., a key switch) to switch the forklift 1 drive ON / OFF, and the safety belt SB may have a mounting sensor to detect when the safety belt SB is being worn. The mounting determination unit 24 may determine that the driver H is not wearing the safety belt SB only when the key switch is ON and the mounting sensor has not detected that the safety belt SB is being worn. This prevents the mounting determination unit 24 from making false detections by detecting the presence or absence of the safety belt SB based solely on the seat image SG.

[0066] The imaging unit 12 may be composed of, for example, a spectroscopic camera, an infrared camera, etc., and the seat image SG may be generated by these cameras. This allows the imaging unit 12 to generate a seat image SG in which the boundary between the safety belt SB and the driver H's clothing is clearer.

[0067] The notification unit 34 may be configured to notify a designated location, such as the manager of driver H or the system managing driver H, of the determination result when it is determined that driver H is not wearing the safety belt SB. In this case, the belt monitoring system S may further include a communication device for making this notification. This allows the belt monitoring system S to assist in the management of safety belt SB wearing. The notification unit 34 may also make different notifications depending on the operation of the forklift 1. The notification unit 34 may also notify driver H that the safety belt SB is not being worn by another notification device, such as a monitor installed on the forklift 1.

[0068] The seatbelt monitoring system S further includes an image storage unit, which may store seat images SG taken during a predetermined time period before and after the time when it is determined that the driver H is not wearing a seatbelt SB. In this case, the predetermined time period before and after may be any time between 5 and 10 seconds before and after the time. The stored seat images SG may also be saved as a video. This allows, for example, an administrator to later refer to the seat images SG stored in the image storage unit. [Explanation of Symbols]

[0069] S Belt Monitoring System C Cable F Hook H Driver SB Safety Belt SG seat image W load 1 Forklift 2 wheels 3. Vehicle Body 4 Mast 5 forks 7 Pillar 8 Headguard 9. Driver's seat 10 Driver's cab 11 Drive unit 12 Photography Department 14 speakers 16 Lifting section 18 Brake 20 Control Unit 22 Motion detection unit 24 Fitting determination unit 240 First pre-trained model 241 Second pre-trained model 26 Height detection unit 28. Load / Absence Detection Unit 29 Speed ​​change section 32 Stop part 34 Notification Department

Claims

1. A camera unit that photographs the driver's seat of a forklift and generates an image of the seat, Based on the aforementioned seat image, the fitting determination unit determines whether or not the driver is wearing a seat belt, A belt monitoring system comprising: a speed change unit that changes the operating speed of the forklift in accordance with each operation of the forklift when it is determined that the driver is not wearing the safety belt.

2. The belt monitoring system according to claim 1, wherein the speed adjustment unit reduces the lifting speed of the forks when it is determined that the driver is not wearing the safety belt while the forklift is raising or lowering its forks.

3. The belt monitoring system according to claim 1, wherein the speed adjustment unit reduces the maximum lifting speed of the fork to between 50 and 150 mm per second when it is determined that the driver is not wearing the safety belt.

4. The belt monitoring system according to claim 1, wherein the speed change unit stops raising the forks when the fork height is higher than a predetermined height and the forklift is loaded with a load, and it is determined that the driver is not wearing the safety belt.

5. The belt monitoring system according to claim 1, wherein the speed change unit stops raising the forks when it is determined that the driver is not wearing the safety belt while the forklift is moving and raising and lowering its forks, and when the forklift is loaded with a load.

6. The belt monitoring system according to claim 1, wherein the speed change unit reduces the travel speed of the forklift when it is determined that the driver is not wearing the safety belt.

7. The belt monitoring system according to claim 1, further comprising a stopping unit that stops the forklift from moving when it is moving and raising / lowering its forks, the height of the forks is higher than a predetermined height, and the forklift is loaded with a load, and it is determined that the driver is not wearing the safety belt.

8. The belt monitoring system according to claim 1, wherein the speed change unit stops the raising of the forks when it is determined that the driver is not wearing the safety belt while the forklift is moving and raising and lowering the forks.

9. The aforementioned mounting determination unit is The system has a pre-trained model that uses multiple seat images as input data and the presence or absence of the seat belt as output data, and has been machine-trained in advance using this training data. When a seat image is input, it outputs a score indicating whether or not the seat belt is being worn. The belt monitoring system according to claim 1, which determines whether the driver is wearing the seat belt based on the score output by the trained model.

10. The forklift has a switch to turn the forklift drive ON / OFF. The safety belt has an attachment sensor that detects when the safety belt is attached. The belt monitoring system according to claim 9, wherein the fitting determination unit determines that the driver is not wearing the safety belt only when the switch is ON and the fitting sensor has not detected that the safety belt is being worn.

11. The fitting determination unit is, A first trained model is pre-trained using training data that takes multiple seat images as input data and whether or not the seat belt is worn as output data, and when a seat image is input, it outputs a score indicating whether or not the seat belt is worn. The system includes a second pre-trained model that is pre-trained using training data that takes multiple consecutive images of the aforementioned seats as input data and outputs whether or not the person is attempting to unbuckle their seat belt as output data, and outputs a score indicating whether or not the person is attempting to unbuckle their seat belt when multiple consecutive images of the aforementioned seats are input, The belt monitoring system according to claim 1, which determines whether the driver is wearing the seat belt based on the scores output by the first and second trained models.

12. The belt monitoring system according to claim 1, further comprising a notification unit that notifies the driver that the driver is not wearing the seat belt when it is determined that the driver is not wearing the seat belt.

13. The belt monitoring system according to claim 1, further comprising an image storage unit that stores images of the seat for a predetermined time before and after the time when it is determined that the driver is not wearing the seat belt.

14. A forklift comprising the belt monitoring system described in any one of claims 1 to 13.

15. A belt monitoring program used in a belt monitoring system having a camera unit that photographs the driver's seat of a forklift and generates a seat image, and a computer, To the aforementioned computer, Based on the aforementioned seat image, the fitting determination unit determines whether or not the forklift driver is wearing a safety belt, A belt monitoring program is executed by a speed change unit that changes the operating speed of the forklift in accordance with each operation of the forklift when it is determined that the driver is not wearing the safety belt.

Images