Construction machine and method for controlling construction machine

Abstract

To provide a towed-type construction machine having improved safety, this construction machine comprises: a towing vehicle that tows a towed vehicle including a reduction gear; and a control measure for predicting deceleration of the towing vehicle and decelerating the towed vehicle by the reduction gear.

Description

Construction machinery and construction machinery control method

[0001] The present invention relates to a construction machine and a control method for the construction machine, and more particularly to a construction machine equipped with a towing vehicle that tows a towed vehicle, and a control method for the construction machine.

[0002] Ensuring safety is important in the automatic operation of a work machine, and Patent Document 1 describes that the work vehicle is slowed down or stopped when a sensor detects an obstacle.

[0003] Japanese Patent Application Laid-Open No. 2022-088097

[0004] However, Patent Document 1 does not propose any safety measures for towed construction machines.

[0005] SUMMARY OF THE INVENTION It is therefore an object of the present invention to provide a towed construction machine and a control method for the construction machine that improves safety.

[0006] The construction machine of the present invention comprises a towing vehicle that tows a towed vehicle equipped with a reduction gear device, and a control device that predicts the deceleration of the towing vehicle and decelerates the towed vehicle using the reduction gear device.

[0007] According to the present invention, a towing vehicle that tows a towed vehicle equipped with a reduction gear device and a control device that predicts the deceleration of the towing vehicle and decelerates the towed vehicle using the reduction gear device are provided, thereby improving the safety of construction work.

[0008] FIG. 1 is a schematic diagram showing a towing vehicle and a scraper vehicle according to the first embodiment. FIG. 2 is a block diagram of the main parts of the towing vehicle and the scraper vehicle according to the first embodiment. FIG. 3(a) to FIG. 3(c) are schematic diagrams showing the positional relationship between the towing vehicle and the scraper vehicle according to the first embodiment, the attitude of the towing vehicle, and the attitude of the scraper vehicle. FIG. 4 is a diagram showing a flowchart executed by the towing vehicle control device according to the first embodiment. FIG. 5(a) and FIG. 5(b) are schematic diagrams showing the towing vehicle and the scraper vehicle according to the second embodiment. FIG. 5 is a schematic diagram showing the separation device according to the second embodiment. FIG. 7(a) to FIG. 7(d) are schematic diagrams showing the operation of the separation device according to the second embodiment. FIG. 8(a) and FIG. 8(b) are schematic diagrams showing the towing vehicle and the scraper vehicle according to the second embodiment repeating the construction process in the construction yard. FIG. 6 is a diagram showing a flowchart executed by the towing vehicle control device according to the second embodiment.

[0009] A first embodiment of the present invention will be described in detail below with reference to the accompanying drawings. However, the present invention is not limited to the embodiment described below.

[0010] (First Embodiment) FIG. 1 is a schematic diagram showing a towed scraper 100 according to the first embodiment. For convenience, in the description of FIG. 1, the vertical axis is referred to as the Z-axis direction, and two orthogonal axes in a horizontal plane are referred to as the X-axis and Y-axis directions. FIG. 2 is a block diagram of a central control device 90 that controls the entire construction site according to the first embodiment, and the main components of the towed scraper 100. The towed scraper 100 is a towed construction machine that repeats four construction steps: an excavation step of excavating excavated material at a predetermined excavation site; a transport step of transporting the excavated material to a predetermined discharge site; a discharge step of discharging the excavated material to the predetermined discharge site; and a transport step of traveling back to the predetermined excavation site. The towed scraper 100 according to the first embodiment includes a towing vehicle 1 as a driving vehicle and a scraper vehicle 20 as a towed vehicle.

[0011] As shown in FIG. 1 , the towing vehicle 1 tows the scraper vehicle 20 via a hitch 21, which is a coupling device. The hitch 21 is detachable from the towing vehicle 1 and has a flexible joint 22 attached to one end of the towing vehicle 1. The joint 22 has degrees of freedom of rotation about the X-axis, the Y-axis, and the Z-axis, and absorbs the inclination of the ground surface. This allows the towing vehicle 1 to tow the scraper vehicle 20 while absorbing the inclination of the ground surface. In this first embodiment, the joint 22 serves as a connection between the towing vehicle 1 and the scraper vehicle 20, and thus serves as a reference for detecting changes in the positions of the towing vehicle 1 and the scraper vehicle 20. In FIG. 1 , the -X direction is the traveling direction of the towed scraper 100. Hereinafter, the towing vehicle 1 and the scraper vehicle 20 will be described in this order using FIGS. 1 and 2 .

[0012] (Towing Vehicle) As shown in FIG. 1 , the towing vehicle 1 of the first embodiment has a frame 2 , front wheels 3 , rear wheels 4 , and a detachable portion 5 .

[0013] As shown in FIG. 2 , the towing vehicle 1 of the first embodiment has a GNSS 6, a speedometer 7, an imaging device 8, a LiDAR 9, an inclinometer 10, an accelerometer 11, a motor 12, a memory 13, a communication device 14, a control device 15, and a hydraulic unit 16, and is connected to a power supply unit (not shown) provided in the towing vehicle 1.

[0014] First, the configuration of the towing vehicle 1 will be described with reference to Figure 1. The frame 2 is a metal member that forms the skeleton of the towing vehicle 1 and is supported by the front wheels 3 and rear wheels 4.

[0015] The front wheels 3 and rear wheels 4 are wheels that drive the entire towing vehicle 1, with two front wheels and four rear wheels. In the first embodiment, instead of an internal combustion engine, the towing vehicle 1 is driven (propelled) using a power supply unit (not shown) provided on the towing vehicle 1 and in-wheel motors 12 (see FIG. 2) provided on each of the two front wheels 3 and four rear wheels 4. The in-wheel motors 12 may be provided so as to be coaxially connected to the hubs of the front and rear wheels.

[0016] The detachable portion 5 is a metal member that serves as a base for attaching and detaching the hitch 21. The detachable portion 5 is disposed on the +X direction side of the frame 2.

[0017] The towing vehicle 1 of the first embodiment is an autonomous type without a driver's seat. The towing vehicle 1 may be a remote-controlled type, a type with a driver's seat, or an internal combustion engine. If the towing vehicle is a type with a driver's seat, it has well-known operating components such as a steering wheel, gear shift lever, turn signals, wipers, an accelerator, and a brake, all of which are not shown.

[0018] Next, the configuration of the towing vehicle 1 will be described further with reference to Figure 2. The GNSS 6 uses artificial satellites to determine the position of the towing vehicle 1. The GNSS 6 is preferably located on top of the towing vehicle 1, where there is good upward visibility, so that data from the artificial satellites can be easily received. The positioning data from the GNSS 6, along with positioning data from the GNSS 33 (described below), is also used to detect relative positional changes between the towing vehicle 1 and the scraper vehicle 20. For this reason, the GNSS 6 and the GNSS 33 are preferably located as far apart as possible in the X direction across the joint 22, so that relative positional changes between the towing vehicle 1 and the scraper vehicle 20 relative to the joint 22 can be easily detected.

[0019] The speedometer 7 detects the speed of the towing vehicle 1 and is a vehicle speed sensor that detects the number of rotations of a shaft connected to the front wheels 3 or the rear wheels 4. Speed ​​detection may also be performed using various sensors, such as a sensor that uses the output of the GNSS 6. Speed ​​detection using the GNSS 6 may also use the method utilizing the Doppler effect described in JP 2019-22108 A.

[0020] The imaging device 8 is a digital camera that has a lens, an imaging element, an image processing engine, etc., and captures video and still images. In this first embodiment, the imaging device 8 is used to capture images of the situation ahead (-X direction) in the direction of travel of the towed scraper 100 shown in FIG. 1 and to detect people, other construction machinery, drones, etc. The imaging device 8 is preferably positioned as far forward (-X direction) as possible from the towing vehicle 1 so that part of the body of the towing vehicle 1 is not captured in the image.

[0021] The LiDAR 9 is a sensor that scans an ultraviolet, visible, or near-infrared pulsed laser, which is an electromagnetic wave, and detects information such as the distance to an object, the shape, material, and color of the object based on the emitted light and scattered light. The LiDAR 9 is an abbreviation for Light Detection and Ranging. In this first embodiment, the LiDAR 9 detects the situation ahead (-X direction) in the direction of travel of the towed scraper 100 shown in FIG. 1 and detects people, other construction machinery, drones, and the like. The LiDAR 9 is preferably positioned as far forward (-X direction) as possible from the towing vehicle 1 so that the pulsed laser is not blocked by part of the towing vehicle 1's body.

[0022] The inclinometer 10 is a sensor that detects the tilt of the body of the towing vehicle 1 in the X direction and the Y direction, i.e., the posture. The inclinometer 10 is preferably disposed on the +X direction side of the frame 2 near the rear wheels 4, which are likely to be linked to the tilt of the ground surface.

[0023] The accelerometer 11 is a sensor that detects acceleration in the Z-axis direction that the towing vehicle 1 receives, and detects unevenness of the ground surface from the vertical acceleration of the towing vehicle 1. The accelerometer 11 is preferably located near the rear wheels 4 of the towing vehicle 1 on the +X-direction side of the frame 2, which has high rigidity.

[0024] As described above, the motors 12 are of the in-wheel type provided on each of the two front wheels 3 and four rear wheels 4 of the towing vehicle 1, and drive the front wheels 3 and rear wheels 4 to rotate.

[0025] The memory 13 is a non-volatile storage device (for example, flash memory) that stores detection data from the GNSS 6, detection data from the speedometer 7, image data from the imaging device 8, detection data from the LiDAR 9, detection data from the inclinometer 10, detection data from the accelerometer 11, dimensional data of the main parts of the towing vehicle 1, and various data for driving the towing vehicle 1. The memory 13 also stores a program for driving the towing vehicle 1.

[0026] The communication device 14 is a wireless communication unit that accesses a communication device of a central control device 90 (to be described later), a communication device 40 (to be described later), and a wide area network such as the Internet.

[0027] The control device 15 is equipped with a CPU and controls the towing vehicle 1. In this first embodiment, the control device 15 automatically drives the towing vehicle 1 at the civil engineering site in accordance with instructions from the central control device 90. The control device 15 also exchanges various data with a control device 41 provided in the scraper vehicle 20 (described below) via the communication device 14 of the towing vehicle 1 and the communication device 40 of the scraper vehicle 20. The control device 15 predicts deceleration of the towing vehicle 1 based on image data from the imaging device 8 and detection data from the LiDAR 9, and instructs the deceleration device provided in the scraper vehicle 20 (described below) to decelerate. The control device 15 also performs safety control, such as receiving emergency signals from other construction machines operating at the construction site and transmitting emergency signals related to the towing vehicle 1 from an alarm device (not shown) to the control devices of other construction machines or to smartphones carried by people. The alarm device (not shown) may transmit emergency signals as sound or light instead of data.

[0028] The hydraulic unit 16 is a drive device that drives a first actuator 28 and a second actuator 30 (described later) that are provided on the scraper vehicle 20. The hydraulic unit 16 also drives a brake (not shown) that is provided on the towing vehicle 1.

[0029] (Scraper vehicle) Next, the scraper vehicle 20 will be described with reference to Figures 1 and 2. As shown in Figure 1, the scraper vehicle 20 has, in addition to the hitch 21 and joint 22 described above, a frame 23, an axle 24, wheels 25, a bowl 26, a scraper 27, a first actuator 28, a ripper 29, a second actuator 30, a protrusion 31, and a blade 32.

[0030] 2, the scraper vehicle 20 has a GNSS 33, an imaging device 34, a LiDAR 35, an inclinometer 36, an accelerometer 37, a load cell 38, a memory 39, a communication device 40, and a control device 41, and is connected to a power supply unit (not shown) provided in the towing vehicle 1. The power supply unit may be provided in the scraper vehicle 20.

[0031] First, the configuration of the scraper vehicle 20 will be described with reference to Figure 1. Note that the hitch 21 and the joint 22 have already been described, so a detailed description thereof will be omitted here.

[0032] The frame 23 is a metal frame that supports a bearing (not shown) that holds the axle 24 and a bowl 26 .

[0033] The axle 24 rotates due to the tractive force of the towing vehicle 1, and the wheels 25 are connected to the axle 24 and are driven wheels that rotate as the axle rotates. The wheels 25 may be provided at the front and rear of the scraper vehicle 20 to serve as front and rear wheels.

[0034] The bowl 26 has an opening (not shown) on the bottom side and is open on the top side, and receives excavated material such as soil and sand excavated by the scraper 27 through this opening (not shown).

[0035] The scraper 27 is a blade- or spatula-shaped member for scraping away excavated material from the traveling surface, such as the ground surface, and in the first embodiment, is provided integrally with the bowl 26 at the bottom of the bowl 26. The scraper 27 also has the effect of slowing down the scraper vehicle 20 by generating resistance when scraping away the excavated material.

[0036] The first actuator 28 is a drive device that tilts the bowl 26 toward the ground surface (-Z direction) and brings it into contact with the ground surface, thereby causing the scraper 27 to dig into the ground surface. When the first actuator 28 tilts the bowl 26 toward the ground surface (-Z direction), the scraper 27 excavates the ground surface, and the excavated material is stored in the bowl 26 through an opening (not shown). When excavation by the scraper 27 is completed, the first actuator 28 tilts the bowl 26 toward the +Z direction, thereby causing the scraper 27 to move away from the ground surface. Here, the first actuator 28 may be a hydraulic cylinder or an electric cylinder.

[0037] In addition, the first actuator 28 decelerates the scraper vehicle 20 by the resistance force generated by contacting the bowl 26 with the ground surface.

[0038] The ripper 29 is a claw-shaped metal member as shown in Figure 1, and is provided to crush hard ground surfaces. The hard ground surface is, for example, soft rock with an N value of over 50. Although one ripper 29 is shown on one side of the bowl 26 in Figure 1, two ripper 29 are provided in total, one on the opposite side (+Y direction side). It is sufficient that at least one ripper 29 is provided, and the number of ripper 29 on each side may be different.

[0039] Furthermore, the mounting position of the ripper 29 does not have to be the side of the bowl 26 as described above, but may be in front of the bowl 26 and on the bottom surface in front of the scraper 27, or may be behind the bowl 26 and on the bottom surface behind the scraper 27. The mounting position of the ripper 29 may also be at the rearmost part of the body of the scraper vehicle 20. If the ripper 29 is mounted in front of the scraper 27, excavation is possible immediately after breaking up the hard ground surface, allowing efficient construction with a single towed scraper 100.

[0040] The second actuator 30 is a drive device that rotates around one end of the ripper 29 as a fulcrum and drives the other end into the ground. The second actuator 30 drives the ripper 29 into the ground, thereby breaking up the ground. The second actuator 30 is a hydraulic motor or an electric motor that drives the ripper 29 around the Y-axis. Although not shown in FIG. 1 , the second actuator 30 may be a hydraulic cylinder or an electric cylinder that moves the ripper 29 in the −Z direction and breaks up the ground by driving it into the ground.

[0041] In addition, the second actuator 30 decelerates the scraper vehicle 20 by using the resistance force generated by driving the ripper 29 into the ground surface.

[0042] In this first embodiment, two sets of ripper 29 and second actuator 30 are provided, one on each side of bowl 26, one being a first contact device and the other being a second contact device.

[0043] The protrusions 31 are protruding members provided in plurality on the bottom of the bowl 26, and are provided to increase resistance and decelerate the towed scraper 100 when the bowl 26 is brought into contact with the ground surface to decelerate the towed scraper 100. In the first embodiment, the protrusions 31 are provided integrally with the bowl 26 on the bottom of the bowl 26. The protrusions 31 are positioned on the +Z side of the scraper 27 so as not to come into contact with the ground surface during excavation. When the bowl 26 is moved to a position on the -Z side from the position during excavation, the protrusions 31 come into contact with the ground surface, making it easier for the scraper vehicle 20 to decelerate.

[0044] The blade 32 is a metal mechanical part that discharges the excavated material contained in the bowl 26 to the discharge location during the discharge process described above. The blade 32 is located on the +X side of the bowl 26 except during the discharge process, and discharges the excavated material by moving it to the −X side by a cylinder (not shown). The cylinder (not shown) may be hydraulically or electrically driven.

[0045] Next, the configuration of the scraper vehicle 20 will be described further with reference to Figure 2. The GNSS 33 is a positioning device similar to the GNSS 2, and determines the position of the scraper vehicle 20. The GNSS 33 is preferably disposed on the top of the scraper vehicle 20 where there is good upward visibility, so that data from artificial satellites can be easily received.

[0046] The imaging device 34 is a digital camera similar to the imaging device 8. In the first embodiment, the imaging device 34 is used to capture images of the situation behind the towed scraper in the traveling direction (+X direction side) and to detect people, other construction machines, drones, and other moving objects. The imaging device 34 is preferably disposed as far back as possible (+X direction side) so that part of the body of the scraper vehicle 20 is not captured in the image.

[0047] The LiDAR 35 is a sensor similar to the LiDAR 9. The LiDAR 35 detects the situation behind (+X direction) the traveling direction of the towed scraper 100 shown in FIG. 1 and is used to detect people, other construction machinery, drones, etc. The LiDAR 35 is preferably disposed as far behind (+X direction) as possible of the scraper vehicle 20 so that the pulsed laser is not blocked by part of the body of the towing vehicle 1.

[0048] The inclinometer 36 has the same function as the inclinometer 10, and detects the inclination of the body of the scraper vehicle 20 in the X direction and the Y direction. The inclinometer 36 is preferably disposed on the +X direction side of the frame 23 near the wheels 25, which are likely to be linked to the inclination of the ground surface. Therefore, the control device 15 can detect changes in the attitude of the towing vehicle 1 and the scraper vehicle 20 based on the outputs of the inclinometer 36 and the inclinometer 10.

[0049] The accelerometer 37 detects acceleration in the Z-axis direction that the scraper vehicle 20 receives. The accelerometer 37 is a sensor that detects unevenness of the ground surface from the acceleration in the up and down directions of the scraper vehicle 20. The accelerometer 37 is preferably disposed near the wheels 25 of the scraper vehicle 20 on the +X-direction side of the frame 23, which has high rigidity.

[0050] The load cell 38 is a known piezoelectric load cell or strain load cell, and detects the weight of the excavated material loaded in the bowl 26. One of the load cells 38 is preferably provided at the end of the joint 22 on the -Z direction side. The other of the load cells 38 is preferably provided between the frame 23 and a bearing (not shown) that rotatably supports the axle 24. The control device 15 can detect the weight of the excavated material loaded in the bowl 26 by calculating the sum of the detection results of the two load cells.

[0051] Memory 39 is a storage device similar to memory 13, and stores detection data from GNSS 33, image data from the imaging device 34, detection data from LiDAR 35, detection data from the inclinometer 36, detection data from the accelerometer 37, and dimensional data of the main parts of the scraper vehicle 20.

[0052] The communication device 40 is a wireless communication unit that accesses a communication device of a central control device 90 (described later), the communication device 14, or a wide area network such as the Internet.

[0053] The control device 41 includes a CPU and controls the scraper vehicle 20. In the first embodiment, the control device 41 transmits image data from the imaging device 34, detection data from the inclinometer 36, and the like to the control device 15 and the central control device 90. The detection timing of the image data from the imaging device 34, detection data from the inclinometer 36, and the like is controlled by the control device 15. The control device 41 also receives instructions from the control device 15 and adjusts the detection time intervals of the various sensors.

[0054] The central control device 90 has a CPU, memory, communication devices, etc., and safely controls the automatic operation of construction machinery including the towed scraper 100 at a construction site. In this first embodiment, the central control device 90 communicates with the control device 15 to transmit driving route data, emergency stop signals, etc. The central control device 90 also communicates with the control device 41 to receive detection results from various sensors provided on the scraper vehicle 20. The central control device 90 is installed in a location different from the towed scraper 100, for example, in a control room outside the construction site. Note that in this first embodiment, the towed scraper 100 may be operated by an operator rather than being automatically operated by the central control device 90.

[0055] Next, changes in the positional relationship and posture between the towing vehicle 1 and the scraper vehicle 20 of the towed scraper 100 of the first embodiment configured as described above will be described using Figures 3(a) to 3(c). As described above, changes in the positional relationship between the towing vehicle 1 and the scraper vehicle 20 are obtained from the detection results of the GNSS 6 and GNSS 33, and changes in posture between the towing vehicle 1 and the scraper vehicle 20 are obtained from the detection results of the inclinometer 10 and the inclinometer 36.

[0056] 3A is a plan view, viewed from the +Z direction, of the scraper vehicle 20 of the towed scraper 100 shown in FIG. 1 , with an angle α rotated clockwise around the Z axis of the joint 22 relative to the traveling direction of the towing vehicle 1. In this state, if the change in angle α over time exceeds a threshold, the body of the towing vehicle 1 is deemed to be abnormal because the body of the towing vehicle 1 is sliding in a direction different from the rotation direction of the rear wheels 4 of the towing vehicle 1 about the Y axis, or the body of the scraper vehicle 20 is sliding in a direction different from the rotation of the wheels 25 of the scraper vehicle 20 about axes extending in the +Y and +X directions. Control in the event of an abnormality will be described later using the flowchart of FIG. 4.

[0057] Figure 3(b) is a view from the -X-axis direction of the towing vehicle 1 shown in Figure 1, with the towing vehicle 1 at an angle β1 in the counterclockwise direction around the X-axis direction relative to the ground. In this state, if the change in angle β1 over time exceeds a threshold, the attitude of the towing vehicle 1 has changed, and there is a risk of it tipping over, which is considered to be an abnormality. Control in the event of an abnormality will be described later using the flowchart in Figure 4.

[0058] 3(c) is a view from the -X-axis direction of the scraper vehicle 20 shown in FIG. 1, with the scraper vehicle 20 at an angle β2 in the counterclockwise direction around the X-axis direction relative to the ground surface. In this state, if the change in angle β2 over time exceeds a threshold, the attitude of the scraper vehicle 20 has changed, and there is a risk of the scraper vehicle 20 tipping over, which is considered to be an abnormality. Control in the event of an abnormality will be described later using the flowchart in FIG. 4.

[0059] (Explanation of Flowchart) Next, the control of the towing vehicle 1 and the scraper vehicle 20 will be explained using the flowchart of FIG.

[0060] Figure 4 is a diagram showing a flowchart executed by the control device 15 provided in the towing vehicle 1 of the first embodiment, and below, the control of the control device 15 of the first embodiment to operate the reduction gear device during construction will be described with reference to Figure 4. The flowchart of Figure 4 is assumed to start when the towed scraper 100 enters the civil construction site and starts traveling.

[0061] When the towed scraper 100 starts moving, the control device 15 collects detection data from the GNSS 6, detection data from the speedometer 7, image data from the imaging device 8, detection data from the LiDAR 9, detection data from the inclinometer 10, detection data from the accelerometer 11, detection data from the GNSS 33, detection data from the imaging device 34, detection data from the LiDAR 35, detection data from the inclinometer 36, detection data from the accelerometer 37, and detection data from the load cell 38, and records the data in the memory 13 (step S1).

[0062] When step S1 is executed, the control device 15 predicts whether deceleration is necessary based on the data collected in step S1 (step S2). This prediction in step S2 is the prediction in the first embodiment. The control device 15 predicts the deceleration of the towing vehicle 1 and whether the deceleration device needs to be activated for the following reasons: First, to stop the towing vehicle 1 and avoid collisions with nearby moving objects such as people, other construction machinery, and drones. Second, to predict changes in the positional relationship and attitude between the towing vehicle 1 and the scraper vehicle 20, predict the risk of the towing vehicle 1 or the scraper vehicle 20 tipping over, and activate the deceleration device to prevent the tipping. In the first embodiment, the control device 15 makes such predictions and activates the deceleration device according to the situation, thereby improving the safety of the construction machinery. Note that the control device 41 may also predict the deceleration of the towing vehicle 1 and whether the deceleration device needs to be activated, and then perform the deceleration control of the scraper vehicle 20 described below. Alternatively, the control devices 15 and 41 may cooperatively control the deceleration of the scraper vehicle 20 described below.

[0063] (Collision Prediction 1) First, a method in which the control device 15 predicts whether or not the operation of the deceleration device is necessary based on image data captured by the imaging device 8 will be described.

[0064] When the imaging device 8 captures an image of a nearby moving object, such as a person, other construction machinery, or a drone, the control device 15 records the captured image data D1 at a first time in the memory 13. After a certain time has passed, the imaging device 8 captures an image of the nearby moving object and records the captured image data D2 at a second time in the memory 13. The control device 15 compares the captured image data D1 and the captured image data D2 through image analysis, and if the control device 15 predicts that the captured image data D2 is closer, it obtains information that the moving object is approaching. When the control device 15 obtains information that the moving object is approaching, it predicts that the towing vehicle 1 will decelerate to avoid a collision between the towed scraper 100 and the moving object. Note that the control device 15 may obtain information that the moving object is approaching based on image data captured by the imaging device 34 instead of the imaging device 8. The control device 15 may also obtain information that the moving object is approaching based on distances detected by the LIDAR 9 or the LIDAR 35 instead of the imaging device 8.

[0065] When the control device 15 receives information that a moving object is approaching, it takes into account the detection results of the speedometer 7 and the load weight of the excavated material detected by the load cell 38 to predict whether contact or collision can be avoided and whether the reduction gear needs to be activated.

[0066] (Collision Prediction 2) Depending on the slope of the traveling location, there may be locations where the imaging device 8 cannot capture an image of a moving object. In particular, in a traveling location where the slope changes from an uphill to a downhill, the imaging device 8 cannot capture an image of a moving object on a downhill slope while the towed scraper 100 is traveling uphill. In such cases, the control device 15 may obtain information that a moving object is approaching by receiving position data of the moving object via communication or by receiving position data and image data of the moving object from a drone (not shown).

[0067] When the control device 15 receives information that a moving object is approaching, it takes into account the detection results of the speedometer 7 and the weight of the excavated material loaded on the bowl 26 detected by the load cell 38 to predict whether contact or collision can be avoided and whether the reduction gear needs to be activated.

[0068] (Fall Prediction 1) Next, a method will be described in which the control device 15 predicts whether the deceleration device needs to be activated based on the positioning data detected by the GNSS 6 and the GNSS 33, and performs deceleration control.

[0069] The control device 15 calculates the angle α shown in Figure 3(a) from the detection results of GNSS 6 and GNSS 33 and the dimensional data of the towed scraper 100 recorded in memory 13 and memory 39, and records this as angle data D3. After a certain time has passed, the control device 15 calculates the angle α shown in Figure 3(a) from the detection results of GNSS 6 and GNSS 33 and the dimensional data of the towed scraper 100, and records this as angle data D4. The control device 15 calculates the change in the angle data D3 and angle data D4 over time, and if the change in the angle α over time becomes greater than a threshold, it predicts that the positional relationship between the towing vehicle 1 and the scraper vehicle 20 is abnormal.

[0070] When the control device 15 receives information that the positional relationship is abnormal, it takes into account the detection results of the speedometer 7 and the load weight of the excavated material detected by the load cell 38, predicts that there is a risk of at least one of the towing vehicle 1 and the scraper vehicle 20 tipping over, and predicts whether the reduction gear needs to be activated.

[0071] (Fall Prediction 2) Next, a method in which the control device 15 predicts whether or not the operation of the deceleration device is necessary based on the tilt data detected by the inclinometer 10 will be described.

[0072] When the inclinometer 10 detects a tilt of the towing vehicle 1, the control device 15 records it in the memory 13 as tilt data D5 for a first time. After a certain time has passed, when the inclinometer 10 detects a tilt of the towing vehicle 1, the control device 15 records it in the memory 13 as tilt data D6 for a second time. The control device 15 calculates the change over time in the tilt data D5 and tilt data D6, and if the change over time in the angle β1 described above exceeds a threshold value, it predicts that the attitude of the towing vehicle 1 is abnormal.

[0073] When the control device 15 receives information that the posture of the towing vehicle 1 is abnormal, it takes into account the detection results of the speedometer 7 and the load weight of the excavated material detected by the load cell 38, predicts that the towing vehicle 1 is at risk of tipping over, and predicts whether the reduction gear needs to be activated.

[0074] (Fall Prediction 3) Next, a method in which the control device 15 predicts whether or not the operation of the reduction gear device is necessary based on the tilt data detected by the inclinometer 36 will be described.

[0075] When the inclinometer 36 detects a tilt of the scraper vehicle 20, the control device 15 records it in the memory 13 as tilt data D7 for a first time. After a certain time has passed, when the inclinometer 36 detects a tilt of the scraper vehicle 20, the control device 15 records it in the memory 13 as tilt data D8 for a second time. The control device 15 calculates the change over time in the tilt data D7 and tilt data D8, and when the change over time in the above-mentioned angle β2 becomes greater than a threshold value, it predicts that the attitude of the towing vehicle 1 is abnormal.

[0076] When the control device 15 receives information that the posture of the scraper vehicle 20 is abnormal, it takes into account the detection results of the speedometer 7 and the load weight of the excavated material detected by the load cell 38, predicts that the scraper vehicle 20 is at risk of tipping over, and predicts whether the reduction gear device needs to be activated.

[0077] If the prediction in step S2 is affirmative, the control device 15 activates the reduction gear (step S3). If the prediction in step S2 is negative, the control device 15 proceeds to step S5. Here, the explanation will be continued assuming that the control device 15 proceeds to step S3. Here, the control device 15 activates the reduction gear in accordance with the prediction in step S2.

[0078] (Deceleration when collision prediction 1 is performed) The control device 15 performs collision prediction 1 in step S2, and if it predicts that contact or collision is unavoidable, it issues a drive command to the first actuator 28 to bring the bowl 26 into contact with the ground surface and decelerate the scraper vehicle 20.

[0079] (Deceleration when collision prediction 2 is performed) The control device 15 performs collision prediction 2 in step S2, and if it predicts that contact or collision is unavoidable, it issues a drive command to the first actuator 28 to bring the bowl 26 into contact with the ground surface and decelerate the scraper vehicle 20.

[0080] (Deceleration when overturn prediction 1 is performed) When the control device 15 performs overturn prediction 1 in step S2 and predicts that at least one of the towing vehicle 1 and the scraper vehicle 20 is at risk of overturning, it activates at least one of the two second actuators 30 provided on both sides of the bowl 26 to drive the ripper 29 into the ground surface in order to eliminate the change in angle α. The control device 15 may also activate the two second actuators 30 to drive the ripper 29 into the ground surface to different depths.

[0081] (Deceleration When Overturn Prediction 2 is Performed) When the control device 15 performs overturn prediction 2 in step S2 and predicts that there is a risk of overturning of the towing vehicle 1, it activates at least one of the two second actuators 30 provided on both sides of the bowl 26 to drive the ripper 29 into the ground surface in order to eliminate the change in angle β1. The control device 15 may also activate the two second actuators 30 to drive the ripper 29 into the ground surface to different depths.

[0082] (Deceleration when overturn prediction 3 is performed) Furthermore, when the control device 15 performs overturn prediction 3 in step S2 and predicts that there is a risk of the scraper vehicle 20 overturning, in order to eliminate the change in angle β2, the control device 15 activates at least one of the two second actuators 30 provided on both sides of the bowl 26 to drive the ripper 29 into the ground surface. Furthermore, the control device 15 may activate the two second actuators 30 to drive the ripper 29 into the ground surface to different depths.

[0083] After step S3 is executed, the control device 15 performs a safety check (step S4). The control device 15 confirms that a collision has been avoided based on the imaging result of the imaging device 8 and the communication result of the communication device 14. The control device 15 also confirms that a fall has been avoided based on the detection result of the inclinometer 10. The control device 15 releases the operation of the reduction gear device described above.

[0084] When step S4 is executed, the control device 15 determines whether construction is continuing (step S5).

[0085] If the result of step S5 is affirmative, the control device 15 returns to step S1. If the result of step S5 is negative, the control device 15 ends this flowchart.

[0086] Furthermore, when the control device 15 predicts that the towing vehicle 1 will decelerate, it may issue an emergency signal from an alarm device (not shown) before activating the deceleration device. The emergency signal may be data sent via the communication device 14, or may be audio or light.

[0087] As described above, in the first embodiment, three reduction gears are provided: a reduction gear configured so that the first actuator 28 tilts the bowl 26 in the −Z direction to cause the scraper 27 to dig into the ground surface, a reduction gear configured so that the first actuator 28 brings the bowl 26 into contact with the ground surface, and a reduction gear configured so that the second actuator 30 brings the ripper 29 into contact with the ground surface. In the flowchart of Fig. 4, the control device 15 operates one reduction gear for one prediction, but it is sufficient for the control device 15 to operate at least one or more of the three reduction gears.

[0088] According to the first embodiment, the control device 15 can operate multiple reduction gears, making deceleration easy. Furthermore, according to the first embodiment, since multiple reduction gears are provided, a highly safe towed construction machine can be provided. Furthermore, according to the first embodiment, the scraper vehicle 20 can be decelerated even without brakes that stop the wheels 25.

[0089] Second Embodiment In the first embodiment, when the control device 15 predicts an abnormality in the positional relationship between the towing vehicle 1 and the scraper vehicle 20, or an abnormality in the attitude of the towing vehicle 1, or an abnormality in the attitude of the scraper vehicle 20, it activates the deceleration device to return the positional relationship and attitude to normal. However, depending on the ground surface conditions, the construction process, the load weight on the bowl 26, the traveling speed of the towed scraper 100, and the stopping distance, there is a risk that the towed scraper 100 may not be able to stop. Furthermore, depending on the change in the positional relationship or attitude between the towing vehicle 1 and the scraper vehicle 20, there is a risk that the tow vehicle 1 or the scraper vehicle 20 may tip over. In the second embodiment, when the control device 15 predicts an abnormality in the positional relationship between the towing vehicle 1 and the scraper vehicle 20, an abnormality in the attitude of the towing vehicle 1, or an abnormality in the attitude of the scraper vehicle 20, the control device 15 takes into account the ground surface conditions, the construction process, the load weight on the bowl 26, and the traveling speed of the towed scraper 100 to predict that at least one of the towing vehicle 1 and the scraper vehicle 20 may tip over, and is provided with a separation device 60 that separates the scraper vehicle 20 from the towing vehicle 1 while the vehicle is traveling.

[0090] The second embodiment will be described below with reference to FIGS. 5A to 9. The same components as those in the first embodiment are denoted by the same reference numerals, and their description will be omitted or simplified.

[0091] FIGS. 5( a) and 5(b) are schematic diagrams of a towed scraper 100 according to the second embodiment. FIG. 5(a) shows the towed scraper 100 according to the second embodiment traveling. As shown in FIG. 5(a), the towing vehicle 1 according to the second embodiment includes a separation device 60 that automatically separates the scraper vehicle 20 from the towing vehicle 1, instead of the detachable unit 5 of the first embodiment. The separation device 60 disconnects the hitch 21, which serves as a coupling device, from the towing vehicle 1 in response to a command from the control device 15, thereby separating the scraper vehicle 20. FIG. 5(b) shows the scraper vehicle 20 separated from the towing vehicle 1 after the separation device 60 has been activated and separated from the connection with the towing vehicle 1. As shown in FIG. 5(b), the scraper vehicle 20 according to the second embodiment includes a connection plate 42 at the lower end of the joint 22. The connection plate 42 is a rectangular plate-shaped member and is housed in a connection frame 62 of the separation device 60, which will be described later.

[0092] Next, the configuration of the connection plate 42 and the separation device 60 will be described using Figure 6. Figure 6 is a cross-sectional view mainly showing the connection plate 42 and the separation device 60, and parts other than the hitch 21, joint 22, connection plate 42, and separation device 60 are omitted. The hitch 21 is illustrated with a portion of the +X direction side omitted. Figure 6 also shows the towing vehicle 1 and scraper vehicle 20 in a separated state.

[0093] First, a description will be given of the configuration of the connection plate 42. The connection plate 42 has a concave electric wire connector 43 and a concave hydraulic coupler 44.

[0094] The concave wire connector 43 is a known wire connector and has a concave electrode 43a at the −Z direction end of the rod-shaped main body. The +Z direction end of the concave wire connector 43 is electrically connected to the GNSS 33, the imaging device 34, the LiDAR 35, the inclinometer 36, the accelerometer 37, the load cell 38, the memory 39, the communication device 40, and the control device 41 provided on the scraper vehicle 20 via electric wires (not shown).

[0095] The concave hydraulic coupler 44 is a known hydraulic coupler and has a concave nozzle 44a at the −Z direction end of the rod-shaped main body. The +Z direction end of the concave hydraulic coupler 44 is connected via hydraulic piping (not shown) to the first actuator 28, the second actuator 30, and a cylinder (not shown) that drives the blade 32, which are provided on the scraper vehicle 20.

[0096] Next, we will continue to explain the configuration of the separation device 60. The separation device 60 has a base plate 61, a connection stand 62, a push-out jack 63, a locking part 64, a convex electric wire connector 65, and a convex hydraulic coupler 66.

[0097] The base plate 61 is a plate-shaped member that serves as the base of the separation device 60 and is provided in accordance with the position of the joint 22 of the towing vehicle 1 .

[0098] The connection base 62 is a block-shaped base with a groove 62a on the +Z direction side and a cylindrical hole 62b on the -Z direction side, with the groove 62a and hole 62b continuing together. The groove 62a is a square groove, and is deep enough so that the +Z direction end of the connection plate 42 does not protrude from the +Z direction end of the connection base 62 when the connection plate 42 is stored. The hole 62b is a cylindrical hole that penetrates in the Z direction to accommodate a push-out jack 63, which will be described later.

[0099] The push-out jack 63 is a hydraulic drive device that separates the scraper vehicle 20 from the towing vehicle 1 and includes a cylinder 63a and a rod 63b. The cylinder 63a is a cylindrical member extending in the Z direction, connected to the hydraulic unit 16, and filled with hydraulic oil to move the rod 63b in the Z direction. The +Z end of the cylinder 63a is equipped with a top plate with a hole through which the rod 63b moves, and the −Z end is equipped with a bottom plate, and is fixed to the +Z side of the base plate 61. The rod 63b is a rod-shaped member extending in the Z direction that fits into the hole in the top plate of the cylinder 63a and moves linearly from the −Z side to the +Z side, pushing the connection plate 42 out of the groove 62a of the connection frame 62. This separates the scraper vehicle 20 from the towing vehicle 1. Alternatively, the rod portion 63b may be fixed to the base plate 61, and the cylinder portion 63a may be arranged to push out the connection plate 42. The push-out jack 63 may be an electric jack.

[0100] The locking component 64 is a rod-shaped member with an X-direction sliding mechanism that locks the connection plate 42 so that the scraper vehicle 20 does not move in the +Z direction and separate when the connection plate 42 is housed in the groove 62a of the connection frame 62. The locking component 64 is provided at the +Z direction end on the -X direction side of the connection frame 62 and is driven by an actuator (not shown). Figure 6 shows the state in which the locking component 64 slides in the -X direction to release the lock on the connection plate 42 and further separate the scraper vehicle 20.

[0101] The convex wire connector 65 is a known wire connector and has a convex electrode 65a at the +Z direction end of its rod-shaped main body. The −Z direction end of the convex wire connector 65 is connected to a power supply unit (not shown) provided in the towing vehicle 1 via an electric wire (not shown). The convex wire connector 65 is paired with the above-mentioned concave wire connector 43, and power is supplied when connected and the power supply is cut off when disconnected.

[0102] The convex hydraulic coupler 66 is a known hydraulic coupler, and has a convex mouthpiece 66a at the +Z direction end of its rod-shaped main body. The -Z direction end of the convex hydraulic coupler 66 is connected to the hydraulic unit 16 provided in the towing vehicle 1 via hydraulic piping (not shown). The convex hydraulic coupler 66 is paired with the above-mentioned concave hydraulic coupler 44, and when connected, hydraulic oil is supplied, and when disconnected, the supply of hydraulic oil is cut off.

[0103] Next, the operation of the separation device 60 will be described using Figures 7(a) to 7(d). Figures 7(a) to 7(d) are cross-sectional views showing the operation of the separation device 60. Figure 7(a) shows a state in which the connection plate 42 is accommodated in the groove 62a of the connection frame 62, and the locking component 64 slides in the +X direction to lock the locking component 64. In this state, the concave electric wire connector 43 and the convex electric wire connector 65 are connected, allowing power to be supplied from the towing vehicle 1 to the scraper vehicle 20. In addition, in this state, the concave hydraulic coupler 44 and the convex hydraulic coupler 66 are connected, allowing hydraulic oil to be supplied from the towing vehicle 1 to the scraper vehicle 20.

[0104] FIG. 7B shows a state in which the locking component 64 has slid in the −X direction and the connection plate 42 has been unlocked.

[0105] 7(c) shows the state in which the push-out jack 63 extends in the +Z direction, pushing up the connection plate 42 in the +Z direction and separating the scraper vehicle 20 from the towing vehicle 1. In FIG. 7(c), the connection between the concave electric wire connector 43 and the convex electric wire connector 65 has been released, cutting off the supply of electric power. The connection between the concave hydraulic coupler 44 and the convex hydraulic coupler 66 has also been released, cutting off the supply of hydraulic oil.

[0106] Figure 7(d) shows the state in which the pusher jack 63 extends further in the +Z direction, pushing the connection plate 42 up in the +Z direction and separating the scraper vehicle 20 from the towing vehicle 1. In Figure 7(d), the connection plate 42 is no longer housed in the groove 62a, allowing the scraper vehicle 20 to move in the +X direction. At this time, the scraper vehicle 20, which does not have a running gear, becomes slower than the towing vehicle 1 due to factors such as the rolling resistance of the wheels 25, and is separated from the towing vehicle 1. Alternatively, a cylinder (not shown) may move the connection plate 42 in the +X direction until the connection plate 42 deviates from the +Z side surface of the connection frame 62, thereby separating the scraper vehicle 20 from the towing vehicle 1.

[0107] 7(c) and 7(d), the separation device 60 of the second embodiment performs electrical separation of the electric wiring and hydraulic separation of the hydraulic piping, and then performs mechanical separation to separate the scraper vehicle 20 from the towing vehicle 1. Performing the separation in this order makes it possible to separate the electric wiring and hydraulic piping without damaging them, and makes it easy to restore the electric wiring and hydraulic piping.

[0108] In the second embodiment, the separation device 60 integrates components for electrical separation, hydraulic separation, and mechanical separation, but each component may be located in a different location, or any two components may be located in the same location. Even if the components are not integrated, it is better to perform electrical separation and hydraulic separation before performing mechanical separation to prevent damage to the electrical wiring and hydraulic piping. Furthermore, because the hydraulic unit 16 is driven by instructions from the control device 15, which is powered by electricity, it is better to perform hydraulic separation before performing electrical separation.

[0109] Furthermore, because hydraulic separation is performed when the separating device 60 is activated, it is preferable that the control device 15 activate the reduction gear before activating the separating device 60. This is because if the control device 15 issues a command to one of the three reduction gears, for example, the second actuator 30, to drive the ripper 29 until it contacts the ground surface, and then issues a command to activate the separating device 60, the scraper vehicle 20 can be separated from the towing vehicle 1 while the ripper 29 is maintained in a position where it can produce a deceleration effect.

[0110] Alternatively, the concave electric wire connector 43 and the concave hydraulic coupler 44 may be provided on the separating device 60, and the convex electric wire connector 65 and the convex hydraulic coupler 66 may be provided on the connecting plate 42.

[0111] Next, a method will be described in which the control device 15 takes into account the risk level H. As described above, in the second embodiment, the control device 15 takes into account the risk level H calculated from the ground surface conditions, the construction process, the load weight on the bowl 26, and the traveling speed of the towed scraper 100, and separates the scraper vehicle 20 from the towing vehicle 1 when it predicts that at least one of the towing vehicle 1 and the scraper vehicle 20 may tip over.

[0112] In the second embodiment, a traveling danger index P is introduced to quantify the danger of the ground surface conditions on which the towed scraper 100 travels. A construction danger index S is also introduced to quantify the danger of the construction process. Furthermore, a momentum M is introduced, which is calculated from the load weight W of the excavated material in the bowl 26 and the traveling speed V of the towed scraper 100. The control device 15 calculates the danger level H by taking into account the traveling danger index P, the construction danger index S, and the momentum M.

[0113] First, the risk index calculated from the ground surface condition and the construction process will be described with reference to Figures 8(a) and 8(b). Figures 8(a) and 8(b) are schematic diagrams showing how the towed scraper 100 in this second embodiment repeats construction processes (excavation process, transport process, discharge process, and forwarding process) in the construction yard 200.

[0114] Figure 8(a) is a plan view showing a state in which a plurality of towed scrapers 100 (six in Figure 8(a)) are present in a construction yard 200. Figure 8(b) is a side view showing an excerpt of a portion of the construction yard 200. As shown in Figure 8(b), the ground surface of the construction yard 200 in this second embodiment slopes downward in the +X direction, is inclined at an angle θ with respect to the horizontal plane, and is a slope with no slope in the +Y direction or the -Y direction.

[0115] 8(a), the construction yard 200 of the second embodiment includes a straight travel path 50a, a curved travel path R1, a straight travel path 50b, and a curved travel path R2 as travel paths for the towed scraper 100. The construction yard 200 also includes an excavation location 51 located in part of the straight travel path 50a where the towed scraper 100 excavates the excavated material, and a discharge location 52 located in part of the straight travel path 50b where the towed scraper 100 discharges the excavated material.

[0116] The towed scraper 100 performs an excavation process at the excavation location 51, then performs a transport process in which it travels on the straight travel path 50a and the curved travel path R1, and heads toward the discharge location 52. Next, the towed scraper 100 performs a discharge process at the discharge location 52, then performs a forwarding process in which it travels on the straight travel path 50b and the curved travel path R2, and returns to the excavation location 51.

[0117] Next, the construction process of the towed scraper 100 in the construction yard 200 of this second embodiment will be described using Figures 8(a) and 8(b). In this second embodiment, the towed scraper 100 will be referred to collectively, and when referring to each of them, alphabets will be added to the reference numerals, such as towed scraper 100a, towed scraper 100b, and towed scraper 100c. When referring to components collectively, they will be referred to as towing vehicle 1, and alphabets will be added to the components, such as towing vehicle 1a, towing vehicle 1b, and towing vehicle 1c.

[0118] The towed scraper 100a is shown traveling down the straight travel path 50a in the +X direction and performing excavation at the excavation location 51. At the excavation location 51 on the straight travel path 50a, the construction process performed by the towed scraper 100a is the excavation process. The towed scraper 100b is shown traveling down the straight travel path 50a in the +X direction with the bowl 26 fully filled with excavated material. The towed scraper 100c is shown traveling along the curved travel path R1 toward the discharge location 52. The construction process performed by the towed scraper 100b traveling along the straight travel path 50a and the towed scraper 100c traveling along the curved travel path R1 is the transport process. The towed scraper 100d is shown traveling up the straight travel path 50b in the -X direction and performing the discharge of the excavated material at the discharge location 52. The construction process performed by the towed scraper 100d at the discharge point 52 on the straight travel path 50b is the discharge process. The towed scraper 100e is shown emptying its bowl 26 and traveling up the straight travel path 50b in the -X direction. The towed scraper 100f is shown traveling along the curved travel path R2 toward the excavation point 51. The construction process performed by the towed scraper 100d traveling along the straight travel path 50b and the towed scraper 100e traveling along the curved travel path R2 is the dead-on process. In this way, the towed scraper 100 repeats the excavation process, the transport process, the discharge process, and the dead-on process while traveling along the straight travel path 50a, the curved travel path R1, the straight travel path 50b, and the curved travel path R2.

[0119] Here, a traveling danger index P is introduced that takes into account the ground surface conditions during travel in the construction yard 200. The traveling danger index P is set to 3 for curved traveling paths, 2 for straight downward traveling paths, and 1 for straight upward traveling paths. The larger the traveling danger index, the more dangerous it is, as it makes it easier to fall when a change in posture occurs. In the second embodiment, the traveling danger index P1 for the curved traveling path R1 is 3, the traveling danger index P2 for the curved traveling path R2 is 3, the traveling danger index P3 for the straight traveling path 50a is 2, and the traveling danger index P4 for the straight traveling path 50b is 1.

[0120] Next, a construction risk index S is introduced that takes the construction process into consideration. Of the construction processes described above, the excavation process is low in risk because the scraper 27 is in contact with the ground surface and resistance to travel is exerted. In this second embodiment, the construction risk index S1 is set to 0.5 for the excavation process, S2 is set to 1 for the transportation process, S3 is set to 1 for the discharge process, and S4 is set to 1 for the forwarding process.

[0121] Next, momentum M is introduced, taking into account weight W and velocity V. The total weight of the towed scraper 100 changes while traveling through the construction yard 200. The total weight of the towed scraper 100 is calculated when the scraper vehicle 20 is not loaded with excavated material (hereinafter referred to as the unloaded state) and when the scraper vehicle is fully loaded with excavated material (hereinafter referred to as the fully loaded state). The tow vehicle 1 of this second embodiment weighs 20 t. The scraper vehicle 20 of this second embodiment weighs 20 t when unloaded. If the load capacity of the bowl 26 of this second embodiment is 40 t, the weight when fully loaded is 60 t. Therefore, the weight W1 of the towed scraper 100 when unloaded is 40 t (= 20 t + 20 t), and the weight W2 when fully loaded is 80 t (= 20 t + 60 t). When fully loaded, it is more difficult to stop and the energy generated when a collision occurs is greater.

[0122] Next, we will continue to explain the traveling speed V. In this second embodiment, the traveling speed V of the towed scraper 100 is V1 = 50 km / h when traveling on the straight traveling path 50a or 50b, V2 = 20 km / h when traveling on the curved traveling path R1 and the curved traveling path R2, and V3 = 10 km / h when performing the excavation process and the discharge process. The faster the traveling speed V, the more difficult it is to stop and the greater the energy generated in the event of a collision.

[0123] Here, momentum M can be expressed as weight W x velocity V. If momentum M is large, it is difficult to decelerate and the impact in the event of a collision is large and dangerous. The largest momentum M is M1 = 80t x 50km / h = 4000t km / h. The smallest momentum M is M2 = 40t x 10km / h = 400t km / h. As you can see, there is a 10-fold difference between momentum M1 and momentum M2, making it difficult to stop and resulting in a large amount of energy in the event of a collision.

[0124] The control device 15 calculates the risk level H from the above-mentioned traveling risk index P, construction risk index S, and momentum M. The risk level H may be calculated by multiplying the traveling risk index P, construction risk index S, and momentum M, or by adding them all together. It is sufficient to set the risk level H using at least one element.

[0125] When driving in an area with a high risk level H, it is preferable to shorten the sampling interval of image data captured by the imaging device 8 so that the control device 15 can predict the amount of change in the data and quickly predict whether the posture is abnormal.

[0126] The elements used to calculate the risk level H are merely examples, and for example, the control device 15 may take into account the slipperiness of the tires based on the amount of moisture on the ground surface, or may predict the unevenness of the ground surface from the detection data of the accelerometers 11 and 37, and take into account the impact on the posture of the towing vehicle 1 and the scraper vehicle 20.

[0127] Next, the control by the control device 15 to operate the separating device 60 will be described using the flowchart of Fig. 9. Fig. 9 is a diagram showing a flowchart executed by the control device 15 provided in the towing vehicle 1 of this second embodiment, and the operation of this second embodiment will be described below with reference to Fig. 9. The flowchart of Fig. 9 is assumed to start when the towed scraper 100 enters the civil engineering work site and starts traveling.

[0128] When the towed scraper 100 starts moving, the control device 15 samples the detection data from GNSS 6, the detection data from the speedometer 7, the image data from the imaging device 8, the detection data from LiDAR 9, the detection data from the inclinometer 10, the detection data from the accelerometer 11, the detection data from GNSS 33, the detection data from the imaging device 34, the detection data from LiDAR 35, the detection data from the inclinometer 36, the detection data from the accelerometer 37, and the detection data from the load cell 38, and records the data in memory 13 (step S101).

[0129] When step S101 is executed, the control device 15 calculates the above-mentioned risk level H (step S102). For example, in the second embodiment, the towed scraper 100b traveling in the construction yard 200 is traveling on the downward straight travel path 50a, so the traveling risk index P3 = 2. Since the construction process is a transportation process, the construction risk index S2 = 1. Since the weight W1 = 80 t and the speed V1 = 50 km / h, the momentum M1 = 4000 t km / h. Here, if the product is taken as the risk level H1, the risk level H1 = P3 × S3 × M1 = 2 × 1 × 4000 = 8000.

[0130] Furthermore, in the second embodiment, the towed scraper 100e traveling in the construction yard 200 is traveling on the ascending straight travel path 50b, so the traveling danger index P4 = 1. Since the construction process is a deadheading process, the construction danger index S4 = 1. Since the weight W2 = 40 t and the speed V1 = 50 km / h, the momentum M2 = 2000 t km / h. Here, if the product is taken as the danger level H2, then the danger level H2 = P4 × S4 × M2 = 1 × 1 × 2000 = 2000.

[0131] (Separation Prediction) When step S102 is executed, the control device 15 detects changes in the positional relationship and attitude between the towing vehicle 1 and the scraper vehicle 20, and if it predicts that the positional relationship and attitude change are abnormal, it predicts whether operation of the separation device 60 is necessary, taking into account the above-mentioned risk level (step S103). In the second embodiment, the threshold value for risk level H is set to 2000. When risk level H exceeds the threshold value, the control device 15 predicts that operation of the separation device 60 is necessary. In the second embodiment, the towed scraper 100b has risk level H2 = 8000, which exceeds the threshold value. Therefore, when the towed scraper 100b corresponds to tipping predictions 1 to 3 of the first embodiment, the control device 15 takes risk level H into account and predicts whether operation of the separation device 60 is necessary.

[0132] The reason why the control device 15 predicts whether operation of the separation device 60 is necessary is to prevent at least one of the towing vehicle 1 and the scraper vehicle 20 from tipping over if there is a risk of the towing vehicle 1 or the scraper vehicle 20 tipping over. This improves the safety of the construction machine during operation. The control device 41 provided in the scraper vehicle 20 may predict the risk of the towing vehicle 1 or the scraper vehicle 20 tipping over and perform the separation control of the separation device 60 described below. The control device 15 and the control device 41 may also perform the separation control of the separation device 60 described below through cooperative control.

[0133] If the prediction in step S103 is affirmative, the control device 15 activates the deceleration device (step S104). If the prediction in step S103 is negative, the control device 15 proceeds to step S108. Here, the explanation will continue assuming that the control device 15 determines that operation of the separation device 60 is necessary and proceeds to step S104. After step S104 is executed, the control device 15 confirms that no moving object is present in the vicinity based on data from the imaging device 34 and LiDAR 35 (step S105). After step S105 is executed, the control device 15 activates the separation device 60 while the towed scraper 100 is traveling (step S106).

[0134] The reason why the control device 15 activates the deceleration device before activating the separation device 60 is to shorten the stop time of the scraper vehicle 20 after separation. The deceleration device to be activated may be at least one of the first actuator 28 that brings the bowl 26 and the scraper 27 into contact with the ground surface, the first contact device that drives the ripper 29 into the ground surface, and the second contact device that drives the ripper 29 into the ground surface. Furthermore, after the first actuator 28 brings the bowl 26 into contact with the ground surface, it may further move in the −Z direction to bring the protrusion 31 into contact with the ground surface.

[0135] The control device 15 may send an emergency signal from an alarm device (not shown) before activating the separating device 60. The emergency signal may be data sent via the communication device 14, or may be sound or light.

[0136] When step S106 is executed and the scraper vehicle 20 is separated from the towing vehicle 1, the control device 15 stops the towing vehicle 1 and checks for safety (step S107). Note that step S107 is the same as step S4 in the flowchart of FIG. 4, and therefore its description will be omitted.

[0137] When step S107 is executed, the control device 15 determines whether construction is continuing (step S108).

[0138] If step S108 is positive, the control device 15 connects the towing vehicle 1 and the scraper vehicle 20, and then returns to step S101. If step S107 is negative, the control device 15 ends this flowchart.

[0139] In the first embodiment, the control device 15 may use the risk level H as a predictive factor when predicting deceleration of the towing vehicle 1.

[0140] As described above, in the second embodiment, when the control device 15 predicts an abnormality in the positional relationship between the towing vehicle 1 and the scraper vehicle 20, an abnormality in the attitude of the towing vehicle 1, or an abnormality in the attitude of the scraper vehicle 20, the control device 15 takes into account the ground surface conditions, the construction process, the load weight of the excavated material in the bowl 26, and the traveling speed of the towed scraper 100 to predict the risk of at least one of the towing vehicle 1 and the scraper vehicle 20 tipping over, and is provided with a separation device 60 that separates the scraper vehicle 20 from the towing vehicle 1 while the towed scraper 100 is traveling. As a result, the towed vehicle 1 and the scraper vehicle 20 can be stopped without tipping over, making it possible to provide a towed construction machine that is very safe.

[0141] In the second embodiment, the threshold value of the risk level H is set to 2000, but is not limited to this. For example, if the weather conditions are such as rain the previous day or if the wind speed during construction exceeds a predetermined wind speed, the threshold value of the risk level H may be set low. Furthermore, if no experience in construction to date fits the fall prediction of the first embodiment, the threshold value of the risk level H may be set high.

[0142] The first and second embodiments described above are merely examples for explaining the present invention, and various modifications can be made without departing from the spirit and scope of the present invention. For example, in the first and second embodiments described above, the towed scraper 100 can be a train-type scraper with multiple scraper vehicles 20 connected together. The multiple scraper vehicles 20 may have the same arrangement of the above-described components, or some of the components may be omitted or their locations may be changed. For example, to reduce weight, the protrusion 31 may not be provided on the scraper vehicle 20 located in the middle. Lightweighting can shorten the time required to stop the vehicle and improve safety.

[0143] DESCRIPTION OF SYMBOLS 1 Towing vehicle 8 Imaging device 10 Inclinometer 15 Control device 20 Scraper vehicle 26 Bowl 27 Scraper 28 First actuator 29 Ripper 30 Second actuator 60 Separation device 100 Towed scraper 200 Construction yard

Claims

1. A towing vehicle that tows a towed vehicle equipped with a reduction gear; a control device that predicts deceleration of the towing vehicle based on a change in posture of at least one of the towing vehicle and the towed vehicle, and decelerates the towed vehicle using the deceleration device.

2. 2. The construction machine according to claim 1, wherein the control device predicts the deceleration of the towing vehicle based on the detection results of a surrounding detection device that detects surrounding moving objects.

3. the surroundings detection device measures a first distance between the towing vehicle and the moving body at a first time; the surroundings detection device measures a second distance between the towing vehicle and the moving body at a second time that is later than the first time; The construction machine according to claim 2 , wherein the control device predicts deceleration of the towing vehicle and controls the reduction gear device when the second distance is shorter than the first distance.

4. 2. The construction machine according to claim 1, wherein the reduction gear transmission decelerates the towed vehicle by a contact device that contacts the ground surface.

5. The towed vehicle has a storage section capable of storing excavated objects, 2. The construction machine according to claim 1, wherein the reduction gear transmission includes a first actuator that brings the housing into contact with the ground surface.

6. a posture detection device for detecting the posture of the towed vehicle; the reduction gear device includes a first contact device provided on one side of the towed vehicle and in contact with the ground, and a second contact device provided on the other side of the towed vehicle and in contact with the ground, 2. The construction machine according to claim 1, wherein the control device predicts deceleration of the towing vehicle based on the detection result of the attitude detection device, and controls at least one of the first contact device and the second contact device.

7. A construction machine as described in claim 1, wherein the control device predicts the deceleration of the towing vehicle by taking into account changes in the weight of the towed vehicle.

8. A construction machine as described in claim 1, wherein the control device predicts the deceleration of the towing vehicle by taking into account the inclination of the driving surface on which the towing vehicle and the towed vehicle are traveling.

9. A towing vehicle to which a towed vehicle can be attached and detached and which tows the towed vehicle; a separation device for separating the towed vehicle from the towing vehicle; a sensor for detecting a state of at least one of the towing vehicle and the towed vehicle; A control device that instructs the separation device to separate based on the detection result of the sensor.

10. 10. The construction machine according to claim 9, wherein the control device takes into account a change in weight of the towed vehicle and instructs the separation device to separate the towed vehicle.

11. 10. The construction machine according to claim 9, wherein the control device instructs the separation device to separate the towed vehicle, taking into account an inclination of a traveling surface on which the towing vehicle and the towed vehicle travel.

12. A construction machine as described in claim 10 or 11, provided with a reduction gear device that decelerates the towed vehicle in response to separation by the separation device.

13. A deceleration device for decelerating the towed vehicle, The construction machine according to claim 9 , wherein the control device drives the reduction gear transmission and then controls the separation by the separation device based on the detection result of the sensor.

14. A step of detecting a moving object approaching at least one of a towed vehicle equipped with a deceleration device and a towing vehicle towing the towed vehicle; and driving the reduction gear by predicting deceleration of the towing vehicle based on a change in attitude of at least one of the towing vehicle and the towed vehicle.

15. A step of detecting a state of at least one of a towing vehicle that is detachable from a towed vehicle and towing the towed vehicle with a sensor; and issuing a command to a separation device that separates the towed vehicle from the towing vehicle based on the detection result of the sensor.

16. A towed vehicle towed by a towing vehicle; a deceleration device that decelerates the towed vehicle in response to a prediction of deceleration of the towing vehicle based on a change in attitude of at least one of the towing vehicle and the towed vehicle; Construction machinery equipped with

17. A towed vehicle to which a towing vehicle can be detached and which is towed by the towing vehicle; a separation device that separates the towed vehicle from the towing vehicle based on the detection results of a sensor that detects the state of at least one of the towing vehicle and the towed vehicle.