Safety devices for remotely operated work vehicles

Abstract

To provide a safety device for remotely operated work vehicles that can improve safety during remote operation. [Solution] The safety device is a remote control for remotely operating the boom and work equipment. The system includes a base 30, a boom attitude detector 120 for detecting the boom's attitude, a remote control position calculation unit 103 for calculating the position of the remote control device 30, a vertical distance calculation unit 106 for calculating the vertical distance between the boom and the remote control device 30, a passage area calculation unit 104 for calculating a boom passage prediction area through which the boom is expected to pass, and a regulation unit 109 that, if the position determination unit 105 determines that the position of the remote control device 30 is within the boom passage prediction area and the distance determination unit 108 determines that the vertical distance between the boom and the remote control device 30 is less than or equal to a determination value, regulates the operation of the boom and / or performs an alarm.

Description

Technical Field

[0001] The present invention relates to a safety device for a remotely-operated work vehicle remotely operated by an operator.

Background Art

[0002] Conventionally, among work vehicles such as aerial work platforms (self-propelled aerial work platforms), digger derrick trucks, crane trucks, and transport carts, remotely-operated work vehicles that enable remote operation from outside the vehicle via a remote control device (remote operation device) have been known (see, for example, Patent Documents 1 to 3).

Prior Art Literature

Patent Literature

[0003]

Patent Document 1

Patent Document 2

Patent Document 3

Summary of the Invention

Problem to be Solved by the Invention

[0004] Such remotely operated work vehicles offer the advantage of improved work efficiency because the operator can freely position themselves while carrying the remote control device, allowing them to operate the vehicle at any suitable location for the task (for example, around the vehicle or near the work object). However, with conventional technology, if the operator is preoccupied with the work object (work location) and the movement of the remotely operated vehicle or the boom or other workpiece attached to the vehicle is not in their field of vision, there is a risk of contact or collision with the vehicle or the workpiece without realizing it is approaching them. Furthermore, depending on the relative position and orientation of the vehicle or the workpiece, the operator may misjudge the direction of operation, and if the vehicle or the workpiece moves in a direction different from the operator's intention, there is a risk that the vehicle or the workpiece will approach against the operator's will and come into contact with or collide with them.

[0005] This invention has been made in view of the above problems, and aims to provide a safety device for a remotely operated work vehicle that can improve safety during remote operation. [Means for solving the problem]

[0006] To solve the above problems, the first safety device for a remotely operated work vehicle according to the present invention comprises a drivable vehicle, a boom mounted on the vehicle so as to be able to rise and fall and rotate, a work device (for example, an auger device 20 and a gripping device 50 in the embodiment) mounted at the tip of the boom, a remote control device (for example, a remote control device 30 in the embodiment) for remotely operating the boom, an operation control unit that controls the operation of the boom based on the operation of the remote control device, a boom posture detection unit (for example, a boom posture detector 120 in the embodiment) for detecting the posture of the boom, and a position calculation unit (for example, a beacon transmitter 35, a beacon receiver 130 and a remote control position calculator in the embodiment) for calculating the position of the remote control device. A projection unit 103), a distance calculation unit (for example, a vertical distance calculation unit 106 in the embodiment) that calculates the distance between the boom and the remote control device, an operating direction calculation unit (for example, a work operation determination unit 102 and a passage area calculation unit 104 in the embodiment) that calculates the operating direction of the boom, a position determination unit that determines whether the position of the remote control device calculated by the position calculation unit is ahead of the operating direction of the boom calculated by the operating direction calculation unit based on the boom posture detected by the boom posture detection unit, a distance determination unit that determines whether the distance between the boom and the remote control device calculated by the distance calculation unit is less than or equal to a predetermined determination value, and the position determination unit determines whether the position of the remote control device is The device is characterized by comprising a regulating unit that, when it is determined that the device is ahead of the boom's operating direction, and the distance determination unit determines that the distance between the boom and the remote control device is less than or equal to the determination value, regulates the operation of the boom and / or activates an alarm.

[0007] In the first safety device for a remotely operated work vehicle according to the present invention described above, it is preferable that the operating direction calculation unit calculates a predicted passage area (for example, the predicted boom passage area BR1 in the embodiment) that the boom is expected to pass through based on the posture of the boom, and the position determination unit determines whether the position of the remotely operated device is ahead of the operating direction of the boom, based on whether the position of the remotely operated device calculated by the position calculation unit is within the predicted passage area calculated by the operating direction calculation unit.

[0008] Furthermore, in the safety device for the remotely operated work vehicle according to the first invention described above, it is preferable to vary the determination value according to the operating speed of the boom.

[0009] The second safety device for a remotely operated work vehicle according to the present invention comprises a drivable vehicle, a work device (for example, a telescopic post 320 and a work platform 330 in the embodiment) provided on the vehicle, a remote control device (for example, a remote control device 350 in the embodiment) for remotely controlling the vehicle's movement, an operation control unit that controls the vehicle's movement based on the operation of the remote control device, a position calculation unit (for example, a beacon transmitter 359, a beacon receiver 360, and a remote control position calculation unit 373 in the embodiment) for calculating the position of the remote control device, a distance calculation unit (for example, a straight-line distance calculation unit 376 in the embodiment) for calculating the distance between the vehicle and the remote control device, and a distance calculation unit that calculates the direction of travel of the vehicle. The system is characterized by comprising: a direction of travel calculation unit (for example, a travel area calculation unit 374 in the embodiment); a position determination unit that determines whether the position of the remote control device calculated by the position calculation unit is ahead of the direction of travel of the vehicle calculated by the direction of travel calculation unit; a distance determination unit that determines whether the distance between the vehicle and the remote control device calculated by the distance calculation unit is less than or equal to a predetermined determination value; and a regulation unit that, if the position determination unit determines that the position of the remote control device is ahead of the direction of travel of the vehicle, and the distance determination unit determines that the distance between the vehicle and the remote control device is less than or equal to the determination value, regulates the vehicle's operation and / or performs an alarm.

[0010] In the second safety device for a remotely operated work vehicle according to the present invention, it is preferable that the direction of travel calculation unit calculates a predicted travel area in which the vehicle is expected to travel based on the direction of travel of the vehicle, and the position determination unit determines whether the position of the remote control device is ahead of the direction of travel of the vehicle, based on whether the position of the remote control device calculated by the position calculation unit is within the predicted travel area calculated by the direction of travel calculation unit.

[0011] Furthermore, in the safety device for the remotely operated work vehicle according to the second invention described above, it is preferable to vary the determination value according to the travel speed of the vehicle. [Effects of the Invention]

[0012] According to the first safety device for a remotely operated work vehicle of the present invention, the position of the remote control device is estimated as the position of the worker remotely operating the boom, and when the remote control device is located ahead in the direction of the boom's operation, and the distance from the boom to the remote control device is less than or equal to a predetermined value, the operation of the boom is restricted and / or an alarm is activated. This allows for accurate determination of the proximity between the two based on the relative positional relationship and distance between the remote control device and the boom in the direction of the boom's operation, thereby preventing the boom from coming into contact with or colliding with the worker during remote operation and improving safety during remote operation.

[0013] Furthermore, according to the first safety device for a remotely operated work vehicle of the present invention, by calculating a predicted passage area through which the boom is expected to pass and determining whether or not the remote control device is within this predicted passage area, it is possible to easily and accurately determine whether the remotely operated boom is approaching the worker, thereby further improving safety during remote operation.

[0014] Furthermore, according to the first safety device for a remotely operated work vehicle of the present invention, by varying the determination value for determining when the boom approaches the remote control device according to the operating speed of the boom, it becomes possible to more reliably prevent the boom from coming into contact with or colliding with a worker while being remotely operated, while suppressing excessive operating restrictions and / or alarm activation.

[0015] According to the second safety device for a remotely operated work vehicle of the present invention, the position of the remote control device is estimated as the position of the operator remotely operating the vehicle. When the remote control device is located ahead in the direction of travel of the vehicle, and the distance from the vehicle to the remote control device is less than or equal to a predetermined value, the vehicle's operation is restricted and / or an alarm is activated. This allows for accurate determination of the proximity between the vehicle and the remote control device based on their relative positions and distance in the direction of travel of the vehicle. As a result, it is possible to prevent the remotely operated vehicle from coming into contact with or colliding with the operator, thereby improving safety during remote operation.

[0016] Further, according to the safety device for a remotely-operated work vehicle according to the second aspect of the present invention, a predicted travel area where a traveling body is predicted to travel is calculated, and whether the remote control device is located within this predicted travel area is determined, whereby it can be easily and more accurately determined that the vehicle under remote control is approaching an operator, and thus the safety during remote control can be further improved.

[0017] Furthermore, according to the safety device for a remotely-operated work vehicle according to the second aspect of the present invention, a determination value for determining that the vehicle (traveling body) has approached the remote control device is varied in accordance with the travel speed, whereby excessive operation restriction and / or alarm activation can be suppressed, and contact or collision of the vehicle under remote control with the operator can be more reliably prevented. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] [Figure 1] FIG. 1 is a side view of the digger derrick according to the first embodiment. [Figure 2] FIG. 2 is a plan view of the digger derrick according to the first embodiment. [Figure 3] FIG. 3 is a schematic diagram showing a use state of the digger derrick according to the first embodiment. [Figure 4] FIG. 4 is a perspective view of a gripping device provided in the digger derrick according to the first embodiment. [Figure 5] FIG. 5 is a right side perspective view of essential parts of the gripping device according to the first embodiment. [Figure 6] FIG. 6 is a left side perspective view of essential parts of the gripping device according to the first embodiment. [Figure 7] FIG. 7 is a cross-sectional view of the gripping device according to the first embodiment. [Figure 8] FIG. 8 is a longitudinal cross-sectional view of the gripping device according to the first embodiment. [Figure 9] FIG. 9 is a functional block diagram of the safety device according to the first embodiment. [Figure 10] FIG. 10 is a schematic diagram showing the arrangement of beacon receivers according to the first embodiment. [Figure 11] FIG. 11 is a schematic diagram for explaining a boom predicted passage area according to the first embodiment. [Figure 12] This is a schematic diagram illustrating the straight-line distance (vertical distance from the bottom of the boom to the remote control device) of the first embodiment. [Figure 13] This is a flowchart showing the procedure for the elevation reduction control process in the first embodiment. [Figure 14] This is a functional block diagram of the safety device according to the second embodiment. [Figure 15] This is a schematic diagram illustrating the boom passage prediction region and straight-line distance (straight-line distance from the side of the boom to the remote control device) of the second embodiment. [Figure 16] This is a flowchart showing the procedure for the turning restriction process in the second embodiment. [Figure 17] This is a perspective view of the aerial work platform according to the third embodiment. [Figure 18] This is a plan view showing the schematic configuration of the traveling body of the third embodiment. [Figure 19] This is a schematic diagram showing the relationship between the extension amount of the steering cylinder and the steering angle of the front wheels in the third embodiment. [Figure 20] This is a functional block diagram of the safety device according to the third embodiment. [Figure 21] This is a schematic diagram showing the arrangement of the beacon receiver in the third embodiment. [Figure 22] This is a schematic diagram illustrating the vehicle's predicted movement region in the third embodiment. [Figure 23] This is a flowchart showing the procedure for the driving restriction process in the third embodiment. [Modes for carrying out the invention]

[0019] Preferred embodiments of the present invention will be described below with reference to the drawings.

[0020] [First Embodiment] First, the overall configuration of the hole-digging and pole-erecting vehicle (gripping type hole-digging and pole-erecting vehicle) 1 equipped with a safety device according to the first embodiment of the present invention will be described with reference to Figures 1 to 3.

[0021] As shown in Figure 1, the hole-digging and pole-erecting vehicle 1 is based on a truck vehicle, having a driver's cabin 7 at the front of the vehicle body 2 and being able to move using a pair of left and right tires 5 positioned at the front and rear of the vehicle body 2. Jacks 9 are provided at four locations on the front, rear, left and right sides of the vehicle body 2 to lift and support it. Each jack 9 lifts and supports the vehicle body 2 by driving a jack cylinder (not shown) located inside it to extend downward, thereby stabilizing the entire vehicle body 2. The operation of the jacks 9 is performed by operating a jack operating device (not shown) located at the rear of the vehicle body 2.

[0022] In the mounting area behind the driver's cabin 7 on the vehicle body 2, a slewing platform 12 is provided, which is driven by a slewing motor 14 (see Figure 9) and is configured to rotate horizontally around a vertical axis. This slewing platform 12 comprises a substantially disc-shaped turntable 12a supported on the vehicle body 2 so as to be able to rotate horizontally, and a support column 12b erected on the turntable 12a. The base end of the boom 13 is pivotally connected to the support column 12b of the slewing platform 12 via a foot pin (pivot point) 12c so as to be able to swing (raise and lower) in the vertical direction.

[0023] The boom 13 has a configuration in which the base boom 13a, intermediate boom 13b, and tip boom 13c are nested together in order from the turntable 12 side. The boom 13 can be extended and retracted in the axial direction (longitudinal direction) by the extension and retraction drive of the telescopic cylinder 15 (see Figure 9) located inside it. In addition, a luffing cylinder 16 (see Figure 3) is mounted between the base boom 13a and the turntable 12, and by driving the extension and retraction of this luffing cylinder 16, the entire boom 13 can be raised and lowered in the upper and lower planes (vertical plane).

[0024] An auger device 20 for excavating holes for erecting pillars is attached to the boom 13 via an auger support 17 that can be selectively connected to the base boom 13a and the tip boom 13c. The auger device 20 consists of an auger motor 21 with a reduction gear and an earth auger 25 that rotates around an axis by rotationally driving the auger motor 21. An auger storage device 18 is also provided on the side of the base boom 13a to hold the auger device 20 in a stored state. The auger device 20 is mounted on the auger support 17 so as to be able to swing up and down in a vertical plane, and can swing between a stored position where the auger device 20 is stored along the side of the base boom 13a by the auger storage device 18 and a working position where the auger device 20 is detached from the auger storage device 18 and the earth auger 25 is in a position approximately vertical to the ground.

[0025] When using the auger device 20, the auger support 17 is positioned at the tip as shown in Figure 3I. By connecting the auger device 20 to the boom 13c and swinging it to the working position (with the earth auger 25 in a nearly vertical position relative to the ground), the earth auger 25 can be rotated while the boom 13's lowering and retracting operations are synchronized to move it linearly downward, enabling the excavation of pole holes. On the other hand, when the auger device 20 is not in use, as shown in II of Figure 3, the auger support 17 is connected to the base boom 13a, and the auger device 20 is stored and held in a storage position along the side of the base boom 13a by the auger storage device 18. When the auger device 20 is in the storage position, various operations such as pole erection (indicated by the symbol P in Figure 3; the same applies hereafter) and obstacle relocation can be performed using the gripping device 50 described later.

[0026] A boom head 19 is fixed to the tip of the tip boom 13c. A gripping device 50 for gripping objects (columnar objects) such as utility poles P or trees is attached to this boom head 19. The configuration of this gripping device 50 will be explained with additional reference to Figures 4 to 8. Note that in Figures 7 to 8, hatching indicating cross-sections has been omitted for clarity. Also, for the sake of explanation, the orientation of the gripping device 50 shown in Figure 4 will be used as the reference point, and the directions of the arrows indicating front / back, left / right, and up / down will be referred to as the front / back direction, left / right direction, and up / down direction.

[0027] The gripping device 50 comprises an arm 51 attached to the boom head 19 so as to be able to swing (bend and extend) in the vertical direction, a first joint member 60 attached to the tip of the arm 51 so as to be able to swing (vertical swivel) in the vertical direction, a second joint member 70 attached to the first joint member 60 so as to be able to swing (lateral swivel) in the left-right direction, and a gripper 80 attached to the second joint member 70 so as to be able to rotate. In this embodiment, the arm 51, the first joint member 60, the second joint member 70, the arm cylinder 55 (described later), the vertical swivel cylinder 62, the horizontal swivel cylinder 71, the gripper motor 79, etc., constitute a support mechanism that changes the posture of the gripping portion 81 of the gripper 80.

[0028] The arm 51 is pivotally connected to the boom head 19 at one end in the axial direction (longitudinal direction) via a connecting pin 52, and its other end in the axial direction (longitudinal direction) is pivotally connected to the first joint member 60 via a connecting pin 53. An arm cylinder 55 is mounted between the boom head 19 and the arm 51. The rod end of the arm cylinder 55 is pivotally connected to the boom head 19 via a connecting pin 56. The bottom end of the arm cylinder 55 is pivotally connected to the arm 51 via a connecting pin 57. By driving the arm cylinder 55 to extend and retract, the arm 51 is configured to swing freely (flex and extend) in the vertical direction around the connecting pin 52 relative to the boom head 19.

[0029] The first joint member 60 is formed in a bifurcated shape with an open tip, and the second joint member 70 is pivotally connected to both ends of this bifurcated shape via a pair of upper and lower connecting pins 61. A vertical swivel cylinder 62 is provided between the first joint member 60 and the arm 51. The bottom end of the vertical swivel cylinder 62 is pivotally connected to the base end of the arm 51 via a connecting pin 63. The rod end of the vertical swivel cylinder 62 is pivotally connected to the upper end of the first joint member 60 via a connecting pin 64. By driving the vertical swivel cylinder 62 to extend and retract, the first joint member 60 is configured to swing freely in the vertical direction (allowing vertical swivel operation) relative to the arm 51 around the connecting pin 53.

[0030] The second joint member 70 is supported by the first joint member 60, sandwiched between it from above and below. A lateral swivel cylinder 71 is provided at the upper end of the first joint member 60. The bottom end of the lateral swivel cylinder 71 is pivotally connected to the tip of the first joint member 60, and the rod end is pivotally connected to the rear end of the second joint member 70. By extending and retracting this lateral swivel cylinder 71, the second joint member 70 can swing freely (laterally swivel) in the left-right direction around the connecting pin 61 relative to the first joint member 60. It is composed of.

[0031] The gripper 80 comprises a gripping portion 81 for gripping an object, a gripper housing 86 that supports the gripping portion 81 and is rotatably mounted on the second joint member 70, and an opening / closing mechanism 93 for opening and closing the gripping portion 81.

[0032] The gripping section 81 comprises a pair of gripping claws 82 and a pair of upper and lower support plates 83 that support the pair of gripping claws 82 so that they can be opened and closed in directions that bring them closer together or further apart (opening and closing directions). The gripping claws 82 are configured to grip various objects (columnar objects) such as utility poles P and trees. The base ends of the gripping claws 82 are pivotally connected to the upper and lower support plates 83 via connecting pins 84. The tips of the gripping claws 82 have alternating notches 82a and 82b, and these tips are configured to intersect (overlap) with each other. The support plates 83 are provided with flat brackets 85 for detachably attaching attachments (not shown) (for example, a tree felling device for felling trees).

[0033] The gripper housing 86 includes a support cylinder portion 87 connected to the upper and lower support plate portions 83 and rotatably supported by the second joint member 70, and a cylinder bracket portion 92 fixed to the base end side of the support cylinder portion 87 and disposed between the first joint member 60 and the second joint member 70.

[0034] The support cylinder portion 87 has a double structure, comprising an inner cylinder portion 88 formed in the shape of a hollow rectangular tube, and an outer cylinder portion 89 formed in the shape of a hollow cylindrical tube and provided on the outer circumference of the inner cylinder portion 88. A sliding member 95 of the opening / closing mechanism 93, described later, is attached to the inner circumference of the inner cylinder portion 88 so as to be slidable in the front-rear direction. A worm wheel 90 is attached to the outer circumference of the outer cylinder portion 89 concentrically with the outer cylinder portion 89. This worm wheel 90 meshes with a worm pinion 91 that is rotatably supported inside the second joint member 70. A gripper motor 79 is attached to the upper end of the second joint member 70, and the worm pinion 91 is connected to the output shaft of this gripper motor 79 via a reduction gear. When this gripper motor 79 is driven to rotate in the forward direction, the entire gripper 80 rotates in a predetermined direction around the rotation axis J (see Figure 7) via the worm pinion 91 and worm wheel 90. On the other hand, when the gripper motor 79 is driven to rotate in the reverse direction, the entire gripper 80 rotates in the opposite direction to the predetermined direction around the rotation axis J (see Figure 7) via the worm pinion 91 and worm wheel 90. In the orientation of the gripping device 50 shown in Figure 4, the direction of the rotation axis J of the gripper 80 (gripping part 81) corresponds to the front-rear direction, and the opening and closing direction (gripping direction) of the gripping part 81 corresponds to the left-right direction.

[0035] The opening / closing mechanism 93 comprises a pair of link members 94, a sliding member 95 linked to the pair of link members 94, and a gripper cylinder 99 that slides the sliding member 95 back and forth. One end of each link member 94 is pivotally connected to the middle part of the gripping claw 81 via a connecting pin 96. The other ends of the pair of link members 94 are also pivotally connected to the tip of the sliding member 95 via a connecting pin 97, with the other ends of each link member 94 overlapping vertically. The sliding member 95 is inserted into the hollow part of the inner cylindrical portion 88 and is mounted so as to be slidable (reciprocal) along the inner circumferential surface of the inner cylindrical portion 88. A slider 98 made of synthetic resin is attached between the outer circumferential surface of the sliding member 95 and the inner circumferential surface of the inner cylindrical portion 88 to guide the sliding (reciprocating) movement of the sliding member 95. The rod-side end of the gripper cylinder 99 is connected to the base end of the sliding member 95. The bottom end of this gripper cylinder 99 is connected to the cylinder bracket portion 92 of the gripper housing 86. When this gripper cylinder 99 is extended, the sliding member 95 slides in the extension direction, causing the link members 94 to swing away from each other. As a result, the gripping claws 82 swing in the opening direction with the connecting pin 84 as the pivot point (the gripping claws 82 operate in the opening direction (opening operation)), The gripper can release a columnar object (target object) such as a utility pole P. On the other hand, when the gripper cylinder 99 is driven to retract, the sliding member 95 slides in the retraction direction, causing the link members 94 to swing toward each other. As a result, the gripping claws 82 swing in the closing direction with the connecting pin 84 as the pivot point (the gripping claws 82 operate in the closing direction (closing operation)), allowing the gripper to hold a columnar object (target object) such as a utility pole P. Since the opening and closing mechanism 93 is configured symmetrically, the pair of gripping claws 82 open and close symmetrically.

[0036] As shown in Figure 9, the hole-digging and pole-erecting vehicle 1 is equipped with a remote control device (remote control device) 30 for remotely controlling the operation of each work device (swivel platform 12, boom 13, auger device 20, gripping device 50). The remote control device 30 is a portable remote control device that is operated by an operator while being held by hand, and can be operated from a position away from the vehicle. This remote control device 30 is connected to the controller 100 (see Figure 9) in a bidirectional manner via a communication device (transceiver / receiver) 39 (see Figure 9), which will be described later. As shown in Figure 9, the remote control device 30 is equipped with a boom rotation and luffing operation lever 32a for rotating and luffing the boom 13, a boom extension and bending operation lever 32b for extending and retracting the boom 13 and bending the arm 51, an auger operation lever 32c for rotating the earth auger 25, a gripper vertical swing operation lever 32d for vertical swing operation of the gripper 81, a gripper horizontal swing operation lever 32e for horizontal swing operation of the gripper 81, a gripper rotation operation lever 32f for rotating the gripper 81, and a gripper opening and closing operation lever 32g for opening and closing the gripper 81.

[0037] The remote control device 30 transmits operation signals as wireless signals in response to the operator's actions. The vehicle body 2 is equipped with a communication device (transceiver) 39 that receives the operation signals wirelessly transmitted from the remote control device 30. When the communication device (transceiver) 39 receives an operation signal from the remote control device 30, it transmits this received operation signal to the controller 100. The communication method between the remote control device 30 and the communication device (transceiver) 39 can be any wireless communication method, such as Wi-Fi (registered trademark), Bluetooth (registered trademark), ZigBee (registered trademark), microwave band communication, or optical communication.

[0038] Here, the operating mechanisms of the turntable 12, boom 13, auger device 20, gripping device 50, etc., as shown in Figure 9, are configured with a controller 100 that receives operation signals from a remote control device 30 and controls the turntable motor 14, telescopic cylinder 15, luffing cylinder 16, auger motor 21, arm cylinder 55, vertical swivel cylinder 62, horizontal swivel cylinder 71, gripper motor 79, and gripper cylinder 99 (hereinafter collectively referred to as "hydraulic actuators"), and a hydraulic unit 115 that supplies hydraulic fluid to drive these hydraulic actuators.

[0039] As described above, the operation signals transmitted (wirelessly transmitted) by the operation of the remote control device 30 (operation levers 32a to 32g) are input to the controller 100 via the communication device (transceiver) 39. The controller 100 outputs a command signal corresponding to the operation signal to the hydraulic unit 115 (control valve section 117).

[0040] The hydraulic unit 115 comprises a hydraulic pump 116 that discharges hydraulic fluid and a control valve section 117 that controls the direction and amount of hydraulic fluid supplied from the hydraulic pump 116 to each hydraulic actuator. The hydraulic pump 116 is driven by power taken from the vehicle's engine via a PTO mechanism (not shown). The control valve section 117 includes an electromagnetic proportional control valve V1 corresponding to the swing motor 14, an electromagnetic proportional control valve V2 corresponding to the telescopic cylinder 15, an electromagnetic proportional control valve V3 corresponding to the luffing cylinder 16, an electromagnetic proportional control valve V4 corresponding to the auger motor 22, an electromagnetic proportional control valve V5 corresponding to the arm cylinder 55, an electromagnetic proportional control valve V6 corresponding to the vertical swivel cylinder 62, and a control valve V6 corresponding to the horizontal swivel cylinder 71. The control valve unit 117 has an electromagnetic proportional control valve V7, an electromagnetic proportional control valve V8 corresponding to the gripper motor 79, and an electromagnetic proportional control valve V9 corresponding to the gripper cylinder 99. Based on command signals from the controller 100, this control valve unit 117 electromagnetically drives the spools of each electromagnetic proportional control valve V1 to V9 to control the supply direction and amount of hydraulic fluid supplied from the hydraulic pump 116 to each hydraulic actuator, and controls the drive direction and drive speed of each hydraulic actuator (controlling the operating direction and operating speed of the turntable 12, boom 13, auger device 20, and gripping device 50).

[0041] However, in a hole-digging and pole-erecting vehicle 1 with this configuration, during excavation or pole-erecting work, if the worker is distracted by the auger in operation and the hole for pole erection, or by the utility pole being erected in the hole, and the movement of the remotely controlled boom 13 is not in their field of vision, there is a risk that they may come into contact with or collide with the boom 13 without realizing it is approaching them. Also, depending on the relative position and orientation of the vehicle and the boom 13, the worker may misinterpret the direction of operation of the remote control device 30, and if the boom 13 moves in a direction different from the direction intended by the worker, there is a risk that the boom 13 may approach against the worker's will and come into contact with or collide with them. Therefore, the hole-digging and pole-erecting vehicle 1 of this embodiment is equipped with a safety device to prevent contact with or collision between the remotely controlled boom 13 and the worker.

[0042] Next, the safety device provided on the hole-digging and pole-erecting vehicle (gripping-type hole-digging and pole-erecting vehicle) 1 of the first embodiment will be explained with additional reference to Figures 9 to 12. The safety device of the first embodiment has a function (collision safety function) to prevent contact or collision between the remotely operated boom 13 and the worker during hole-digging work using the auger device 20 or pole-erecting work using the gripping device 50. Note that in Figure 10, the boom 13, auger device 20 and gripping device 50 are omitted from the illustration for the sake of clarity. Similarly, in Figures 11 and 12, the auger device 20 and gripping device 50 are omitted from the illustration for the sake of clarity.

[0043] As shown in Figure 9, the safety device of the first embodiment mainly consists of a boom attitude detector 120, a remote control device 30, a beacon transmitter 35, a beacon receiver 130, and a controller 100.

[0044] The boom attitude detector 120 detects the attitude of the boom 13 (elevation angle, extension amount, and slewing angle). This boom attitude detector 120 includes a boom elevation angle detector 121, a boom extension amount detector 122, and a boom slewing angle detector 123. The boom elevation angle detector 121 is located inside the base boom 13a and detects the elevation angle of the boom 13. The boom extension amount detector 122 is located at the base end of the base boom 13a and detects the length (extension amount) of the boom 13. The boom slewing angle detector 123 is located on the vehicle body 2 and detects the slewing angle of the boom 13 (slewing platform 12) relative to the vehicle body 2. These detectors 121 to 123 are electrically connected to the controller 100 and output voltage signals (detection signals) to the controller 100 according to the detected information (elevation angle, extension amount, and slewing angle of the boom 13).

[0045] As shown in Figures 9 and 10, a beacon transmitter 35 is attached to the remote control device 30. The beacon transmitter 35 is, for example, a small transmitting module that incorporates a transmitting circuit and a battery. The beacon transmitter 35 transmits beacon signals in a frequency band based on short-range wireless communication standards such as Wi-Fi®, Bluetooth®, ZigBee®, microwave band communication, and optical communication as radio signals at predetermined time intervals. The beacon signal includes unique identification information (beacon ID) to identify its own beacon transmitter 35.

[0046] As shown in Figure 10, the beacon receiving device 130 consists of three beacon receivers (first beacon receiver 131, second beacon receiver 131) mounted on the turntable 12a of the rotating platform 12. The system includes a third beacon receiver (132) and a third beacon receiver (133). Each beacon receiver (131-133) is positioned at equal intervals (120-degree intervals) in the circumferential direction with respect to the pivot center O of the turntable (boom 13). However, each beacon receiver (131-133) may be positioned at other locations on the vehicle body (2) as long as their position relative to the pivot center O of the turntable (boom 13) can be determined. Each beacon receiver (131-133) is equipped with a radio wave sensor (not shown) that detects the radio wave strength (received radio wave strength) when it receives a beacon signal from the beacon transmitter (35). Each beacon receiver (131-133) receives a beacon signal transmitted from the beacon transmitter (35) and detects the radio wave strength (received radio wave strength) of that beacon signal, thereby acquiring the beacon ID attached to the beacon signal and the radio wave strength information (received radio wave strength) at the time of receiving that beacon signal, and transmits this acquired information to the controller (100) as beacon information.

[0047] As shown in Figure 9, the controller 100 includes an operation control unit 101, a work operation determination unit 102, a remote control position calculation unit 103, a passage area calculation unit 104, a position determination unit 105, a vertical distance calculation unit 106, a determination value calculation unit 107, a distance determination unit 108, and a regulation unit 109.

[0048] The operation control unit 101 controls the drive of each hydraulic actuator according to the operation signals (wireless signals) transmitted from the remote control device 30 via the communication device (transceiver) 39. Specifically, when the boom slewing / luffing operation lever 32a is tilted forward (in the forward, backward, left, and right directions relative to the operator operating it; the same applies hereinafter), the luffing cylinder 16 is driven to retract, causing the boom 13 to be lowered. When the boom slewing / luffing operation lever 32a is tilted backward, the luffing cylinder 16 is driven to extend, causing the boom 13 to be raised. Also, when the boom extension / bending operation lever 32b is tilted forward, the extension cylinder 15 is driven to extend, causing the boom 13 to be extended. When the boom extension / bending operation lever 32b is tilted backward, the extension cylinder 15 is driven to retract, causing the boom 13 to be retracted. Furthermore, when the boom slewing / luffing operation lever 32a is tilted to the left, the slewing motor 14 is driven to rotate in the forward direction, causing the boom 13 to slewing counterclockwise. When the boom slewing / luffing operation lever 32a is tilted to the right, the slewing motor 14 is driven to rotate in the reverse direction, causing the boom 13 to slewing clockwise. Also, when the auger operation lever 32c is tilted forward, the auger motor 21 is driven to rotate in the reverse direction, causing the earth auger 25 to rotate in the reverse direction. When the auger operation lever 32c is tilted backward, the auger motor 21 is driven to rotate in the forward direction, causing the earth auger 25 to rotate in the forward direction. Furthermore, when the boom extension / bending operation lever 32b is tilted to the left, the arm cylinder 55 is driven to retract, causing the arm 51 to bend downward relative to the tip of the boom 13, and when the boom extension / bending operation lever 32b is tilted to the right, the arm cylinder 55 is driven to extend, causing the arm 51 to bend upward relative to the tip of the boom 13. Also, when the gripping part vertical swivel operation lever 32d is tilted forward, the vertical swivel cylinder 62 is driven to extend, causing the gripping part 81 to swing downward (vertical swivel operation), and when the gripping part vertical swivel operation lever 32d is tilted backward, the vertical swivel cylinder 62 is driven to retract, causing the gripping part 81 to swing upward (vertical swivel operation).Furthermore, when the gripping unit lateral swing operation lever 32e is tilted to the left, the lateral swing cylinder 71 is extended to swing the gripping unit 81 to the left (lateral swing operation), and when the gripping unit lateral swing operation lever 32e is tilted to the right, the lateral swing cylinder 71 is retracted to swing the gripping unit 81 to the right (lateral swing operation). Also, when the gripping unit rotation operation lever 32f is tilted forward, the gripper motor 79 is driven to rotate clockwise, and when the gripping unit rotation operation lever 32f is tilted backward, the gripper motor 79 is driven to rotate counterclockwise, and the gripping unit 81 is driven counterclockwise. Furthermore, when the gripping section opening / closing lever 32g is tilted forward, the gripper cylinder 99 is driven to retract, causing the gripping section 81 to close (to grip the object), and when the gripping section opening / closing lever 32g is tilted backward, the gripper cylinder 99 is driven to extend, causing the gripping section 81 to open (to release the object).

[0049] The operation determination unit 102 determines whether or not the boom 13 is being lowered (collapsed) based on the operation signal from the boom slewing and luffing operation lever 32a. In other words, the operation determination unit 102 determines whether or not the operating direction of the boom 13 is the luffing direction (collapse direction).

[0050] The remote control position calculation unit 103 calculates the distance between the beacon transmitter 35 and each of the beacon receivers 133-133 based on the beacon information transmitted from the beacon receiving device 130 (three beacon receivers 131-133). Here, the received radio wave strength (radio wave level) received by each of the beacon receivers 131-133 has the property that it is inversely proportional to the square of the distance from the beacon transmitter 35 that is the source of the signal (it becomes stronger as the distance from the source decreases, and weaker as the distance from the source increases). Therefore, in this embodiment, this property of received radio wave strength is used to calculate the distance between the beacon transmitter 35 and each of the beacon receivers 131-133 based on the received radio wave strength from the beacon transmitter 35 received by each of the beacon receivers 131-133. Specifically, the remote control position calculation unit 103 calculates the distance between the beacon transmitter 35 and the first beacon receiver 131 based on the received radio wave strength from the beacon transmitter 35 received by the first beacon receiver 131, calculates the distance between the beacon transmitter 35 and the second beacon receiver 132 based on the received radio wave strength from the beacon transmitter 35 received by the second beacon receiver 132, and calculates the distance between the beacon transmitter 35 and the third beacon receiver 133 based on the received radio wave strength from the beacon transmitter 35 received by the third beacon receiver 133.

[0051] Furthermore, the remote control position calculation unit 103 calculates the position of the beacon transmitter 35 (i.e., the position of the remote control device 30) relative to the pivot center O of the turntable 12 (boom 13) based on the three distances calculated above. Here, since the remote control position calculation unit 103 has the positions of the three beacon receivers 131 to 133 relative to the pivot center O stored as known information, it can calculate the relative position of the beacon transmitter 35 (remote control device 30) relative to the pivot center O using the so-called three-point positioning principle based on the distance between the beacon transmitter 35 and each beacon receiver 131 to 133. The position of the remote control device 30 can be represented, for example, in an XYZ coordinate system (orthogonal three-axis coordinate system) with the pivot center O of the turntable 12 (boom 13) as the origin, the vehicle width direction (left-right direction) of the vehicle body 2 as the X axis, the vehicle length direction (front-rear direction) of the vehicle body 2 as the Y axis, and the vehicle height direction (up-down direction) of the vehicle body 2 as the Z axis. Furthermore, the Z-axis position of the remote control device 30 is set to a predetermined fixed position (higher than the worker's height) without depending on the detection results (received radio wave strength) of the beacon receivers 131-133, in order to prevent contact between the boom 13 and the worker (especially the worker's head). For example, the Z-axis position of the remote control device 30 is set to a height position that adds a predetermined margin to the standard height of a person (worker) (for example, a height of 2m above the ground).

[0052] If the work operation determination unit 102 determines that the boom 13 is being raised or lowered (when the boom 13 is operating in the raising or lowering direction), the passage area calculation unit 104 calculates the predicted boom passage area BR1, which is the area that the boom 13 is expected to pass through when it is raised or lowered (collapsed), based on the attitude of the boom 13 detected by the boom attitude detector 120. As shown in Figure 11, the predicted boom passage area BR1 is the area around the lower area located on the lower side (raised or lowering direction) of the boom 13, plus a margin area of ​​a predetermined width. In other words, the predicted boom passage area BR1 is the area where the lower surface of the boom 13 may come into contact with the worker when the boom 13 is raised or lowered.

[0053] The position determination unit 105 determines whether or not the remote control device 30 is within the boom passage prediction area BR1 based on the position of the remote control device 30 calculated by the remote control position calculation unit 103 and the boom passage prediction area BR1 calculated by the passage area calculation unit 104. In terms of configuration, the presence of the remote control device 30 within the boom passage prediction area BR1 means that an operator (an operator operating the remote control device 30) is located ahead of the operating direction (loudness / downward direction) of the boom 13.

[0054] The vertical distance calculation unit 106 calculates the distance BD1 from the bottom surface of the boom 13 to the remote control device 30 (referred to as the "vertical distance") based on the attitude of the boom 13 detected by the boom attitude detector 120 and the position of the remote control 30 (position in the XYZ axis direction) calculated by the remote control position calculation unit 103. The vertical distance BD1 is the difference between the ground height Ta of a predetermined measurement point BP1 on the bottom surface of the boom 13 and the ground height Tb of the remote control device 30, as shown in Figure 12(A). The predetermined measurement point BP1 is the point projected perpendicularly onto the bottom surface of the boom 13 at the point where the circumference BC1 passing through the remote control device 30 with the pivot center O of the boom 13 as the center intersects with the central axis (axis line) BJ of the boom 13 in the plan view shown in Figure 12(B).

[0055] The determination value calculation unit 107 calculates a determination value (threshold) to determine whether the boom 13, which is in luffing / lowering operation, is approaching the remote control device 30 (operator), based on the output value of the luffing command signal transmitted by the operation control unit 101 to the electromagnetic proportional control valve V3 and the position of the remote control device 30 relative to the pivot center O (distance from the pivot center O to the remote control device 30) calculated by the remote control position calculation unit 103. In this embodiment, the output value of the luffing command signal and the determination value are in a nearly proportional relationship, and the larger the output value of the luffing command signal to the electromagnetic proportional control valve V3 (i.e., the valve opening of the electromagnetic proportional control valve V3 and the driving speed of the luffing cylinder 1), the larger the determination value is set to be. Furthermore, in this embodiment, even if the luffing speed (luffing / lowering speed) of the boom 13 is the same, the amount of displacement per unit time (luffing operation) is smaller towards the base end of the boom 13, and the amount of displacement per unit time (luffing operation) is larger towards the tip end of the boom 13. Therefore, the closer the position of the remote control device 30 is to the pivot center O, the smaller the judgment value is set, and the further the position of the remote control device 30 is from the pivot center O, the larger the judgment value is set.

[0056] The distance determination unit 108 determines whether the vertical distance BD1 calculated by the vertical distance calculation unit 106 is less than or equal to the determination value calculated by the determination value calculation unit 107. If the distance determination unit 108 determines that the vertical distance BD1 from the lower surface of the boom 13 (measurement point BP1) to the remote control device 30 is less than or equal to the determination value (vertical distance BD1 ≤ determination value), it determines that the remote control device 30 (operator) is near the boom 13 during luffing and lowering operation (it determines that the boom 13 during luffing and lowering operation is approaching the operator).

[0057] The regulating unit 109 transmits a regulating signal to the operation control unit 101 to regulate the operation (luffing and lowering operation) of the boom 13, and transmits an alarm signal to the alarm device 34 to activate the alarm device 34, when the operation control unit 102 determines that luffing and lowering operation is being performed, the position determination unit 105 determines that the remote control device 30 is within the boom passage prediction area BR1, and the distance determination unit 108 determines that the vertical distance BD1 is less than or equal to a determination value. In addition, the regulating unit 109 transmits an alarm signal to the operation control unit 101 to regulate the operation (luffing and lowering operation) of the boom 13, and transmits an alarm signal to the alarm device 34 to activate the alarm device 34. Regarding the regulation of the operation of the boom 13, the operation control unit 101 may be configured to impose an operation restriction on the operation control unit 101, such as by not accepting the operation signal when the operation control unit 101 receives a regulating signal from the regulating unit 109, or by not electromagnetically driving the electromagnetic proportional control valve V3 even if the operation control unit 101 accepts the operation signal.

[0058] The alarm device 34 consists of, for example, an alarm buzzer, an alarm lamp, a display monitor, and an audio speaker, and is designed to alert the worker by issuing an alarm in response to an alarm signal from the control unit 109 (an alarm to warn the worker that the operation of the boom 13 has been restricted). This alarm device 34 includes all means that can alert the worker through sight, hearing, etc. Furthermore, since this alarm device 34 is installed in the remote control device 30, the above alarm signal is transmitted from the control unit 109 to the communication device 39. The information is transmitted wirelessly to device 34. The alarm device 34 may also be mounted on the vehicle body 2 (for example, the driver's cabin 7 or the cargo bed).

[0059] Furthermore, the regulating unit 109 may change the content of the alarm according to the vertical distance BD1 (distance from the bottom surface of the boom 13 to the remote control device 30) calculated by the vertical distance calculation unit 106. For example, as the bottom surface of the boom 13 approaches the remote control device 30 (operator), the volume of the sound used for the alarm may be increased as the vertical distance BD1 decreases, or the color of the lamp used for the alarm may be changed. In addition, the alarm operation of the alarm device 34 may be started before regulating (stopping) the luffing and lowering operation of the boom 13. For example, the alarm operation of the alarm device 34 may be started when the vertical distance BD1 becomes less than or equal to a first judgment value, and the luffing and lowering operation of the boom 13 may be regulated (stopped) when the vertical distance BD1 becomes less than or equal to a second judgment value (provided that the second judgment value < the first judgment value).

[0060] Next, the elevation reduction control process performed in the safety device of the first embodiment will be described. Figure 13 is a flowchart showing the procedure for the elevation reduction control process performed in the safety device of the first embodiment.

[0061] First, in step S11, the work operation determination unit 102 determines whether or not there is a luffing down operation input (input of a luffing down operation signal) from the boom slewing luffing operation lever 32a. If the work operation determination unit 102 determines that there is a luffing down operation input (step S11: YES), it proceeds to step S12. On the other hand, if the work operation determination unit 102 determines that there is no luffing down operation input (step S11: NO), it terminates the current process.

[0062] In step S12, the remote control position calculation unit 103 calculates the positional relationship between the vehicle and the remote control device 30 (the position of the remote control device 30 relative to the turning center O) based on the detected values ​​(received radio wave strength) of the beacon receivers 131 to 133.

[0063] In step S13, the passage area calculation unit 104 calculates the predicted boom passage area BR1, which is the area that the boom 13 is expected to pass through when it performs luffing down (collapse) operation, based on the attitude of the boom 13 detected by the boom attitude detector 120.

[0064] In step S14, the position determination unit 105 determines whether the remote control device 30 is within the boom passage prediction region BR1 based on the position of the remote control device 30 relative to the pivot center O calculated in step S12 and the boom passage prediction region BR1 calculated in step S13. If the position determination unit 105 determines that the remote control device 30 is within the boom passage prediction region BR1 (step S14: YES), it proceeds to step S15. On the other hand, if the position determination unit 105 determines that the remote control device 30 is not within the boom passage prediction region BR1 (step S14: NO), it terminates the current process.

[0065] In step S15, the vertical distance calculation unit 106 calculates the vertical distance BD1 from the lower surface of the boom 13 (measurement point BP1) to the remote control device 30 based on the attitude of the boom 13 detected by the boom attitude detector 120 and the position of the remote control device 30 with respect to the pivot center O (position in the XYZ axis direction) calculated in step S12.

[0066] In step S16, the determination value calculation unit 107 calculates a determination value (threshold) based on the output value of the elevation command signal transmitted by the operation control unit 101 to the electromagnetic proportional control valve V3 and the position of the remote control device 30 with respect to the pivot center O calculated in step S12 (distance from the pivot center O to the remote control device 30).

[0067] In step S17, the distance determination unit 108 determines the vertical distance calculated in step S15. Based on BD1 and the determination value calculated in step S16, the distance determination unit 108 determines whether the vertical distance BD1 is less than or equal to the determination value. If the distance determination unit 108 determines that the vertical distance BD1 is less than or equal to the determination value (step S17: YES), it proceeds to step S18. On the other hand, if the distance determination unit 108 determines that the vertical distance BD1 is not less than or equal to the determination value (step S17: NO), it terminates the current process.

[0068] In step S18, the regulating unit 109 transmits a regulating signal to the operation control unit 101 to regulate the operation (luffing and lowering) of the boom 13. The regulating unit 109 also wirelessly transmits an alarm signal to the alarm device 34 via the communication device 39 to activate the alarm device 34.

[0069] As described above, according to the safety device of the first embodiment, the position of the remote control device 30 is estimated as the position of the worker remotely operating the boom 13. When the remote control device 30 is located ahead of the operating direction (luffing / lowering direction) of the boom 13, and the vertical distance BD1 from the lower surface of the boom 13 (measurement point BP1) to the remote control device 30 is less than or equal to a determination value, the operation of the boom 13 (luffing / lowering operation) is restricted and an alarm is activated. This allows for accurate determination of the proximity of the two based on the relative positional relationship and distance between the boom 13 and the remote control device 30 in the operating direction (luffing / lowering direction), thereby preventing the boom 13 from coming into contact with or colliding with the worker during remote operation and improving safety during remote operation.

[0070] Furthermore, according to the safety device of the first embodiment, by calculating the boom passage prediction area BR1 through which the boom 13 is expected to pass, and determining whether or not the remote control device 30 is within this boom passage prediction area BR1, it is possible to easily and accurately determine whether the remotely operated boom 13 is approaching the operator, thereby further improving safety during remote operation.

[0071] Furthermore, according to the safety device of the first embodiment, by varying the determination value for determining when the boom 13 approaches the remote control device 30 according to the operating speed (elevation / lowering speed) of the boom 13, it is possible to more reliably prevent the boom 13 from coming into contact with or colliding with a worker while remotely controlling it, while suppressing excessive operation restrictions and / or alarm activation.

[0072] [Second Embodiment] Next, a safety device according to the second embodiment of the present invention will be described with reference to Figures 14 to 15. The safety device of the second embodiment is applied to the hole-digging pole-erecting vehicle (gripping type hole-digging pole-erecting vehicle) 1, similar to the safety device of the first embodiment described above. In the safety device of the first embodiment described above, the relative positional relationship and distance between the boom 13 and the remote control device (remote operation device) 30 during the luffing and lowering operation of the boom 13 was used as the basis for determination, but in this safety device of the second embodiment, the relative positional relationship and distance between the boom 13 and the remote control device (remote operation device) 30 during the slewing operation of the boom 13 is used as the basis for determination. In the following description, the same numbers will be used for components (or components with the same function) as in the first embodiment above, and redundant explanations will be omitted. The description will mainly focus on the parts that differ from the first embodiment above.

[0073] The safety device of the second embodiment, as shown in Figure 14, mainly consists of a boom attitude detector 120, a remote control device 30, a beacon transmitter 35, a beacon receiver 130, and a controller 200. This safety device of the second embodiment has a function (collision safety function) to prevent collision or contact between the remotely operated boom 13 and the worker during excavation work for pole installation using the auger device 20 or pole installation work for utility poles using the gripping device 50. Note that the boom attitude detector 120, remote control device 30, beacon transmitter 35, and beacon receiver 130 have the same configuration as in the first embodiment described above, so a redundant explanation is omitted here. Also, in Figure 15, the auger device 20 and gripping device 50 are omitted from the illustration for clarity of the explanation.

[0074] As shown in Figure 14, the controller 200 includes an operation control unit 101, a work posture determination unit 201, a work operation determination unit 202, a remote control position calculation unit 103, a passage area calculation unit 204, a position determination unit 205, a straight-line distance calculation unit 206, a determination value calculation unit 207, a distance determination unit 208, and a regulation unit 209. Note that the operation control unit 101 and the remote control position calculation unit 103 have the same configuration as in the first embodiment described above, so a redundant explanation is omitted here.

[0075] The working posture determination unit 201 determines whether the elevation angle of the boom 13 is less than or equal to a predetermined angle (e.g., 5 degrees) based on the posture of the boom 13 detected by the boom posture detector 120. In other words, the working posture determination unit 201 determines whether the posture of the boom 13 is such that it may come into contact with a worker when the boom 13 is rotated. This determination condition is based on the premise that if the boom 13 is rotated while its elevation angle is less than or equal to a predetermined angle (e.g., 5 degrees), there is a risk that the side of the boom 13 may come into contact with or collide with a worker.

[0076] The operation determination unit 202 determines whether or not a slewing operation of the boom 13 is being performed based on the operation signal from the boom slewing and luffing operation lever 32a. In other words, the operation determination unit 202 determines whether or not the operating direction of the boom 13 is the slewing direction.

[0077] When the operation determination unit 202 determines that the boom 13 is being rotated (i.e., the operating direction of the boom 13 is the rotation direction), the passage area calculation unit 204 calculates the boom passage prediction area BR2, which is predicted to be passed through when the boom 13 rotates, based on the posture of the boom 13 detected by the boom posture detector 120 and the operation signal from the boom rotation luffing operation lever 32a (the rotation direction of the boom 13). The boom passage prediction area BR2 is the area that is predicted to be passed through when the boom 13 is rotated by a specified angle (e.g., 45 degrees) from the current rotation position in the current rotation direction, as shown in the plan view in Figure 15(A).

[0078] The position determination unit 205 determines whether or not the remote control device 30 is within the boom passage prediction area BR2, based on the position of the remote control device 30 calculated by the remote control position calculation unit 103 and the boom passage prediction area BR2 calculated by the passage area calculation unit 204. In this embodiment, the presence of the remote control device 30 within the boom passage prediction area BR2 means that an operator (an operator who operates the remote control device 30) is located ahead of the operating direction (rotation direction) of the boom 13.

[0079] The straight-line distance calculation unit 206 calculates the distance BD2 from the side of the boom 13 to the remote control device 30 (referred to as the "straight-line distance") based on the attitude of the boom 13 detected by the boom attitude detector 120, the operation signal from the boom slewing / luffing operation lever 32a (direction of the boom 13's rotation), and the position of the remote control device 30 (position in the XYZ axis direction) calculated by the remote control position calculation unit 103. This straight-line distance BD2 is the straight-line distance between a predetermined measurement point BP2 on the side of the boom 13 (the side on the rotation direction side) and the remote control device 30 in the plan view shown in Figure 15(B). The predetermined measurement point BP2 is the point where the circumference BC2 passing through the remote control device 30 with the rotation center O of the boom 13 as the center intersects with the side of the boom 13 (the side on the rotation direction side) in the plan view shown in Figure 15(B).

[0080] The determination value calculation unit 207 calculates a determination value (threshold) for determining whether the boom 13, which is in rotational operation, is approaching the remote control device 30 (operator), based on the output value of the rotation command signal transmitted by the operation control unit 101 to the electromagnetic proportional control valve V1 and the position of the remote control device 30 relative to the rotation center O (distance from the rotation center O to the remote control device 30) calculated by the remote control position calculation unit 103. In this embodiment, the output value of the rotation command signal and the determination value are approximately equal. In this example, the larger the output value of the slewing command signal to the electromagnetic proportional control valve V1 (i.e., the valve opening of the electromagnetic proportional control valve V1 and the drive speed of the slewing motor 14), the larger the judgment value is set to be. Furthermore, in this embodiment, even if the slewing speed of the boom 13 is the same, the amount of displacement per unit time (slewing operation amount) is smaller towards the base end of the boom 13, and the amount of displacement per unit time (slewing operation amount) of the boom 13 is larger towards the tip end of the boom 13. Therefore, the closer the position of the remote control device 30 is to the slewing center O, the smaller the judgment value is set to be, and the further the position of the remote control device 30 is from the slewing center O, the larger the judgment value is set to be.

[0081] The distance determination unit 208 determines whether the straight-line distance BD2 calculated by the straight-line distance calculation unit 206 is less than or equal to the determination value calculated by the determination value calculation unit 207. If the distance determination unit 208 determines that the straight-line distance BD2 from the side of the boom 13 (measurement point BP2) to the remote control device 30 is less than or equal to the determination value (vertical distance BD2 ≤ determination value), it determines that the remote control device 30 (worker) is near the boom 13 during rotation (it determines that the boom 13 during rotation is approaching the worker).

[0082] If the operation determination unit 202 determines that a slewing operation is being performed, the position determination unit 205 determines that the remote control device 30 is within the boom passage prediction area BR2, and the distance determination unit 208 determines that the straight-line distance BD2 is less than or equal to a determination value, the regulating unit 209 transmits a regulating signal to the operation control unit 101 to regulate the operation (slewing operation) of the boom 13, and transmits an alarm signal to the alarm device 34 via the communication device 39 to activate the alarm device 34.

[0083] Furthermore, the regulating unit 209 may change the content of the alarm according to the straight-line distance BD2 (distance from the side of the boom 13 to the remote control device 30) calculated by the straight-line distance calculation unit 206. For example, the volume of the voice used for the alarm may be increased as the straight-line distance BD2 decreases, or the color of the lamp used for the alarm may be changed. In addition, the alarm operation of the alarm device 34 may be started before regulating (stopping) the rotational operation of the boom 13. For example, the alarm operation of the alarm device 34 may be started when the straight-line distance BD2 becomes less than or equal to a first determination value, and the rotational operation of the boom 13 may be regulated (stopped) when the straight-line distance BD2 becomes less than or equal to a second determination value (provided that the second determination value < the first determination value).

[0084] Next, the turning restriction process performed in the safety device of the second embodiment will be described. Figure 16 is a flowchart showing the procedure for the turning restriction process performed in the safety device of the second embodiment.

[0085] First, in step S21, the work operation determination unit 202 determines whether or not there is a slewing operation input (input of a slewing operation signal) from the boom slewing / luffing operation lever 32a. If the work operation determination unit 202 determines that there is a slewing operation input (step S21: YES), it proceeds to step S22. On the other hand, if the work operation determination unit 202 determines that there is no slewing operation input (step S21: NO), it terminates the current process.

[0086] In step S22, the working posture determination unit 201 determines whether the elevation angle of the boom 13 is less than or equal to a predetermined angle (for example, 5 degrees) based on the posture of the boom 13 detected by the boom posture detector 120. If the working posture determination unit 201 determines that the elevation angle of the boom 13 is less than or equal to the predetermined angle (step S22: YES), it proceeds to step S23. On the other hand, if the working posture determination unit 201 determines that the elevation angle of the boom 13 is not less than or equal to the predetermined angle (step S22: NO), it terminates the current process.

[0087] In step S23, the remote control position calculation unit 103 calculates the positional relationship between the vehicle and the remote control device 30 (while turning) based on the detected values ​​(received radio wave strength) of the beacon receivers 131 to 133. The position of the remote control device 30 relative to the heart O is calculated.

[0088] In step S24, the passage area calculation unit 204 calculates the predicted boom passage area BR2, which is the area that the boom 13 is expected to pass through when it rotates, based on the attitude of the boom 13 detected by the boom attitude detector 120 and the operation signal from the boom slewing / luffing operation lever 32a (direction of rotation of the boom 13).

[0089] In step S25, the position determination unit 205 determines whether the remote control device 30 is within the boom passage prediction area BR2 based on the position of the remote control device 30 relative to the pivot center O calculated in step S23 and the boom passage prediction area BR2 calculated in step S24. If the position determination unit 205 determines that the remote control device 30 is within the boom passage prediction area BR2 (step S25: YES), it proceeds to step S26. On the other hand, if the position determination unit 205 determines that the remote control device 30 is not within the boom passage prediction area BR2 (step S25: NO), it terminates the current process.

[0090] In step S26, the straight-line distance calculation unit 206 calculates the straight-line distance BD2 from the side of the boom 13 (the side on the rotation direction side) to the remote control device 30 based on the attitude of the boom 13 detected by the boom attitude detector 120, the operation signal from the boom slewing and luffing operation lever 32a (the rotation direction of the boom 13), and the position of the remote control device 30 with respect to the slewing center O calculated in step S23 (the position in the XYZ axis direction).

[0091] In step S27, the determination value calculation unit 207 calculates a determination value (threshold) based on the output value of the swivel command signal transmitted by the operation control unit 101 to the electromagnetic proportional control valve V1 and the position of the remote control device 30 with respect to the swivel center O calculated in step S23 (distance from the swivel center O to the remote control device 30).

[0092] In step S28, the distance determination unit 208 determines whether the straight-line distance BD2 is less than or equal to the determination value calculated in step S27, based on the straight-line distance BD2 calculated in step S26 and the determination value calculated in step S27. If the distance determination unit 208 determines that the straight-line distance BD2 is less than or equal to the determination value (step S28: YES), it proceeds to step S29. On the other hand, if the distance determination unit 208 determines that the straight-line distance BD2 is not less than or equal to the determination value (step S28: NO), it terminates the current process.

[0093] In step S29, the regulating unit 209 transmits a regulating signal to the operation control unit 101 to regulate the operation (slewing operation) of the boom 13. The regulating unit 209 also wirelessly transmits an alarm signal to the alarm device 34 via the communication device 39 to activate the alarm device 34.

[0094] As described above, according to the safety device of the second embodiment, the position of the remote control device 30 is estimated as the position of the worker remotely operating the boom 13. When the remote control device 30 is located ahead of the operating direction (rotation direction) of the boom 13, and the straight-line distance BD2 from the side of the boom 13 to the remote control device 30 is less than or equal to a determination value, the operation (rotation operation) of the boom 13 is restricted and an alarm is activated. This allows for accurate determination of the proximity of the two based on the relative positional relationship and distance between the boom 13 and the remote control device 30 in the operating direction (rotation direction), thereby preventing the boom 13 from coming into contact with or colliding with the worker during remote operation and improving safety during remote operation.

[0095] Furthermore, according to the safety device of the second embodiment, by calculating the boom passage prediction area BR2 through which the boom 13 is expected to pass, and determining whether or not the remote control device 30 is within this boom passage prediction area BR2, it is possible to easily and accurately determine whether the remotely operated boom 13 is approaching the operator, thereby further improving safety during remote operation. This becomes possible.

[0096] Furthermore, according to the safety device of the second embodiment, by varying the determination value for determining when the boom 13 approaches the remote control device 30 according to the operating speed (slewing speed) of the boom 13, it is possible to more reliably prevent the boom 13 from coming into contact with or colliding with a worker while remotely controlling it, while suppressing excessive operation restrictions and / or alarm activation.

[0097] [Third Embodiment] Next, the overall configuration of the self-propelled aerial work platform 301 (hereinafter also simply referred to as "vehicle") equipped with a safety device according to the third embodiment of the present invention will be described with reference to Figures 17 to 19. In the following description, the vehicle length direction of the aerial work platform 301 will be referred to as the front-rear direction, the vehicle width direction as the left-right direction, and the vehicle height direction as the up-down direction.

[0098] The aerial work platform 301 is comprised of a mobile body 310 having four wheels 311 (a pair of front wheels 311a and rear wheels 311b) located on the front, rear, left, and right sides, a telescopic post 320 extending vertically upward from the mobile body 310, and a work platform 330 for workers supported by the telescopic post 320. The mobile body 310 is equipped with a mobile motor (hydraulic motor) 312 inside (see Figure 18), which drives the rear wheels 311b (also referred to as "drive wheels 311b") and steers the front wheels 311a (also referred to as "steering wheels 311a"), allowing it to move.

[0099] The front wheel (steering wheel) 311a and the steering dial 342 (see Figure 20) are indirectly linked via the steering device. As shown in Figure 18, the steering device consists of a steering linkage mechanism 313 connected to the front wheel 311a, a steering cylinder (hydraulic cylinder) 317 that drives the steering linkage mechanism 313 to change the steering angle γ of the front wheel 311a (the deflection angle of the front wheel 311a with respect to the longitudinal central axis of the vehicle body 310, see Figure 19), and a steering angle detector 309 (see Figure 20) that detects the steering angle γ of the front wheel 311a.

[0100] As shown in Figure 18, the steering linkage mechanism 313 is composed of left and right front wheel support members 314 that rotatably support the front wheel 311a, and a tie rod 316 that connects the left and right front wheel support members 314. Each of the left and right front wheel support members 314 is attached to the vehicle body 310 via a kingpin 315 that extends in the vertical direction, and is able to swing around the kingpin 315. In addition, each of the left and right front wheel support members 314 is provided with an arm portion 314a that extends to the rear of the vehicle body 310. Both ends of the tie rod 316 are connected to the arm portions 314a of the left and right front wheel support members 314 by connecting pins P1.

[0101] One end of the steering cylinder 317 is connected by a connecting pin P2 to the arm portion 314a of the left front wheel support member 314, which constitutes the steering linkage mechanism 313. The other end of the steering cylinder 317 is connected by a connecting pin P3 to a cylinder connecting portion (not shown) of the vehicle body 310. Therefore, by extending and retracting the steering cylinder 317, the left front wheel support member 314 can be swung around the kingpin 315, and the right front wheel support member 314 can be swung simultaneously and in the same direction as the left front wheel support member 314 via the tie rod 316. Furthermore, by extending the steering cylinder 317, the left and right front wheels 311a can be turned to the right, and by retracting the steering cylinder 317, the left and right front wheels 311a can be turned to the left.

[0102] As shown in Figure 19, when the extension amount Δ of the steering cylinder 317 is zero (Δ=0), the steering angle γ of the front wheel 311a is zero (γ=0) (see Figure 19(A)). Here, we define the sign of the steering angle γ when the front wheel 311a is deflected to the right as positive, and the sign of the steering angle γ when the front wheel 311a is deflected to the left as negative. When the extension amount Δ of the steering cylinder 317 is a positive value (Δ>0) When the steering angle γ of the front wheel 311a is positive (γ>0), see Figure 19(B). When the extension / contraction amount Δ of the steering cylinder 317 is negative (Δ<0), the steering angle γ of the front wheel 311a is negative (γ<0) (see Figure 19(C)).

[0103] As shown in Figure 18, the left and right rear wheels 311b are attached to the left and right axles 319. The left and right axles 319 are connected to the drive motor 312 via multiple gears in the gearbox 318. Therefore, the driving force of the drive motor 312 is transmitted to the left and right rear wheels (drive wheels) 311b via the multiple gears in the gearbox 318 and the left and right axles 319.

[0104] As shown in Figure 17, the telescopic post 320 consists of a lower post 321 extending vertically upward from the traveling body 310 and an upper post 322 nested within the lower post 321. The telescopic post 320 incorporates a lifting cylinder (hydraulic cylinder) 323 (see Figure 20), and the upper post 322 can be raised and lowered vertically by the extension and retraction of the lifting cylinder 323, allowing the post to be extended and retracted vertically. The work platform 330 is attached to the upper post 322 and can be raised and lowered by the vertical extension and retraction of the telescopic post 320.

[0105] An upper operating device 340 is attached to the work platform 330. As shown in Figure 20, the upper operating device 340 is equipped with a travel operation lever 341 for operating the travel unit 310 (starting, stopping, switching between forward and reverse, and adjusting the speed while traveling), a steering dial 342 for operating the travel unit 310 (steering the front wheels 311a), and a lifting operation lever 343 for raising and lowering the work platform 330. The operating state of the travel operation lever 341, the steering dial 342, and the lifting operation lever 343 (operating direction and amount relative to the neutral position) is detected by an operation detector such as a potentiometer, and the detection signal is input to the controller 370, described later, as an operation signal corresponding to the operating state of the travel operation lever 341, the steering dial 342, and the lifting operation lever 343 (operating direction and amount relative to the neutral position). In this way, a worker on the work platform 330 can move the vehicle (work platform 330) to any desired work position by operating the upper operating device 340 to perform various operational operations such as the movement of the vehicle 310 (rotational drive of the travel motor 312), the steering of the vehicle 310 (extension and retraction drive of the steering cylinder 317), and the raising and lowering of the work platform 330 (extension and retraction drive of the lifting cylinder 323).

[0106] In addition, the aerial work platform 301 is equipped with a remote control device (remote control unit) 350 (see Figure 20) for remotely operating the vehicle (traveling body 310), separate from the upper operating device 340. The remote control device 350 is a portable remote control device that is operated by an operator while being held by hand, and can be operated from a position away from the vehicle. This remote control device 350 is connected to the controller 370 (see Figure 20) via a communication device 306 (see Figure 20), which will be described later, and is capable of bidirectional communication.

[0107] As shown in Figure 20, the remote control device 350 is equipped with a forward drive switch 351, a reverse drive switch 352, a left steering switch 353, a right steering switch 354, and a speed selector switch 355. The remote control device 350 may also be a terminal device such as a smartphone.

[0108] The forward drive switch 351 is a push-button switch operated when moving the vehicle 310 forward (forward driving). The reverse drive switch 352 is a push-button switch operated when moving the vehicle 310 backward (reverse driving). The left steering switch 353 is a push-button switch operated when steering the front wheels (steering wheels) 311a to the left. The right steering switch 354 is used to steer the front wheels (steering wheels) 311a to the right. These are push-button type switches that are operated when starting or stopping. In the following text, the forward drive switch 351 and the reverse drive switch 352 may be collectively referred to as the "driving operation switches." Also, the left steering switch 353 and the right steering switch 354 may be collectively referred to as the "steering operation switches."

[0109] The travel speed selector switch 355 is a toggle switch operated to switch the travel speed of the travel body 310 in three stages (low speed, medium speed, and high speed). This travel speed selector switch 355 can be switched to one of the following positions: neutral, forward, or rear (the operator can release their hand and the switch will maintain the selected operating position). When the forward position is selected, low speed (low speed mode) is set; when the neutral position is selected, medium speed (medium speed mode) is set; and when the rear position is selected, high speed (high speed mode) is set.

[0110] The remote control device 350 transmits operation signals as wireless signals in response to the operator's actions. The mobile unit 310 is equipped with a communication device 306 (see Figure 20) that receives the operation signals wirelessly transmitted from the remote control device 350. When the communication device 306 receives an operation signal from the remote control device 350, it transmits this received operation signal to the controller 370. The communication method between the remote control device 350 and the communication device 306 can be any wireless communication method, such as Wi-Fi®, Bluetooth®, ZigBee®, microwave communication, or optical communication.

[0111] As shown in Figure 20, the operating mechanism of the aerial work platform 301 is configured to include a controller 370 that receives operation signals from the upper operating device 340 and the remote control device 350 and controls the travel motor 312, steering cylinder 317, lifting cylinder 323, etc. (hereinafter collectively referred to as "hydraulic actuators"), and a hydraulic unit 390 that supplies hydraulic fluid to drive these hydraulic actuators.

[0112] The hydraulic unit 390 comprises a hydraulic tank 391 for storing hydraulic fluid, a hydraulic pump 392 that discharges hydraulic fluid when driven by a power source (not shown) such as an electric motor or a small engine, and a control valve section 393 that controls the direction and amount of hydraulic fluid supplied from the hydraulic pump 392 to each hydraulic actuator. The control valve section 393 includes a travel control valve (electromagnetic proportional control valve) SV1 corresponding to the travel motor 312, a steering control valve (electromagnetic proportional control valve) SV2 corresponding to the steering cylinder 317, and a lifting control valve (electromagnetic proportional control valve) SV3 corresponding to the lifting cylinder 323. Based on command signals from the operation control section 371 of the controller 370, the control valve section 393 electromagnetically drives the spools of each control valve (electromagnetic proportional control valve) SV1 to SV3 to control the direction and amount of hydraulic fluid supplied from the hydraulic pump 392 to each hydraulic actuator, and controls the driving direction and driving speed of each hydraulic actuator.

[0113] However, with aerial work platform 301 configured in this way, if the worker is preoccupied with the work object or the direction of the vehicle's movement and the movement of the remotely controlled vehicle is not in their field of vision, there is a risk of contact or collision with the vehicle without realizing that it is approaching. Also, depending on the relative position and orientation to the vehicle, the worker may misinterpret the operating direction of the remote control device 350, and if the vehicle moves in a direction different from the direction the worker intended, there is a risk that the vehicle will approach against the worker's will and cause contact or collision. Therefore, the aerial work platform 301 of this embodiment is equipped with a safety device to prevent contact or collision between the remotely controlled vehicle (mobile body 310) and the worker.

[0114] Next, the safety device of the third embodiment will be described. The safety device of the third embodiment has a function (collision safety function) to prevent contact or collision between the remotely operated aerial work platform 301 and the worker. Therefore, in the following, the operating means provided on the aerial work platform 301 will be described. The following describes how to remotely operate the aerial work platform 301 using the remote control device 350 (the operation of the upper control device 340 will be omitted).

[0115] As shown in Figure 20, the safety device of the first embodiment mainly consists of a rudder angle detector 309, a remote control device 350, a beacon transmitter 359, a beacon receiver 360, and a controller 370.

[0116] The steering angle detector 309 detects the steering angle γ of the front wheel (steering wheel) 311a from its neutral position. The steering angle detector 309 detects the steering angle γ when the front wheel 311a is turned to the right (steering angle γ during a right turn) as a positive value, and the steering angle γ when the front wheel 311a is turned to the left (steering angle γ during a left turn) as a negative value. The steering angle detector 309 is electrically connected to the controller 370 and outputs a voltage signal (detection signal) corresponding to the detected steering angle γ to the controller 370.

[0117] A beacon transmitter 359 is attached to the remote control device 350. The beacon transmitter 359 is, for example, a small transmitting module that incorporates a transmitting circuit and a battery. The beacon transmitter 359 transmits beacon signals as radio signals at predetermined time intervals in a frequency band based on short-range wireless communication standards such as Wi-Fi®, Bluetooth®, ZigBee®, microwave band communication, and optical communication. The beacon signal includes unique identification information (beacon ID) to identify its own beacon transmitter 359.

[0118] As shown in Figure 21, the beacon receiving device 360 ​​includes a left front beacon receiver 361 located at the left front corner of the vehicle 310, a right front beacon receiver 362 located at the right front corner of the vehicle 310, a left rear beacon receiver 363 located at the left rear corner of the vehicle 310, and a right rear beacon receiver 364 located at the right rear corner of the vehicle 310. Note that each beacon receiver 361 to 364 may be placed at other locations on the vehicle 310 or on the workbench 330, as long as their position relative to the vehicle center C can be determined. Each beacon receiver 361 to 364 is equipped with a radio wave sensor (not shown) that detects the radio wave strength (received radio wave strength) when it receives a beacon signal from the beacon transmitter 359. Each beacon receiver 361 to 364 receives a beacon signal transmitted from the beacon transmitter 359 and detects the radio wave strength (received radio wave strength) of that beacon signal. Thereafter, it obtains the beacon ID attached to the beacon signal and the radio wave strength information (received radio wave strength) at the time the beacon signal was received, and transmits this obtained information to the controller 370 as beacon information.

[0119] The controller 370 includes an operation control unit 371, a driving operation determination unit 372, a remote control position calculation unit 373, a travel area calculation unit 374, a position determination unit 375, a straight-line distance calculation unit 376, a determination value calculation unit 377, a distance determination unit 378, and a regulation unit 379.

[0120] The operation control unit 371 transmits command signals (control signals) corresponding to the operation signals from the remote control device 350 to each control valve SV1, SV2, and electromagnetically drives each control valve SV1, SV2 to control the driving direction and driving speed of each hydraulic actuator (travel motor 312, steering cylinder 317).

[0121] Specifically, when the operation control unit 371 receives operation signals from the travel operation switches (forward travel switch 351, reverse travel switch 352) and the travel speed selector switch 355, it transmits a travel command signal to the travel control valve SV1 that commands the forward / reverse direction (forward direction, reverse direction) and travel speed (low speed, medium speed, high speed) of the travel body 310. The operation control unit 371 controls the movement direction of the spool of the travel control valve SV1 and the valve opening degree so that the travel body 310 operates in the commanded forward / reverse direction (forward direction, reverse direction) and travel speed (low speed, medium speed, high speed), thereby controlling the travel mode Controls the drive direction and drive speed of the 312.

[0122] Furthermore, when the operation control unit 371 receives operation signals from the steering operation switches (left steering switch 353, right steering switch 354), it transmits a steering command signal to the steering control valve SV2 that commands the steering direction (left turn direction, right turn direction) and steering speed of the front wheels 311a. The operation control unit 371 controls the movement direction of the spool of the steering control valve SV2 and the valve opening degree so that the front wheels 311a steer in the commanded steering direction (left turn direction, right turn direction) and steering speed, thereby controlling the drive direction and drive speed of the steering cylinder 317.

[0123] The driving operation determination unit 372 determines whether or not the driving unit 310 is being driven (forward operation, reverse operation) based on operation signals wirelessly transmitted from the driving operation switches (forward driving switch 351, reverse driving switch 352).

[0124] The remote control position calculation unit 373 calculates the distance between the beacon transmitter 359 and each beacon receiver 361 to 364 based on the beacon information transmitted from the beacon receiving device 360 ​​(four beacon receivers 361 to 364). Here, the received radio wave strength (radio wave level) received by each beacon receiver 361 to 364 has the property that it is inversely proportional to the square of the distance from the beacon transmitter 359 that is the source of the signal (it becomes stronger as the distance from the source decreases, and weaker as the distance from the source increases). Therefore, in this embodiment, this property of received radio wave strength is used to calculate the distance between the beacon transmitter 359 and each beacon receiver 361 to 364 based on the received radio wave strength from the beacon transmitter 359 received by each beacon receiver 361 to 364. Specifically, the remote control position calculation unit 373 calculates the distance between the beacon transmitter 359 and the left front beacon receiver 361 based on the received radio wave strength from the beacon transmitter 359 received by the left front beacon receiver 361, calculates the distance between the beacon transmitter 359 and the right front beacon receiver 362 based on the received radio wave strength from the beacon transmitter 359 received by the right front beacon receiver 362, calculates the distance between the beacon transmitter 359 and the left rear beacon receiver 363 based on the received radio wave strength from the beacon transmitter 359 received by the left rear beacon receiver 363, and calculates the distance between the beacon transmitter 359 and the right rear beacon receiver 364 based on the received radio wave strength from the beacon transmitter 359 received by the right rear beacon receiver 364.

[0125] Furthermore, the remote control position calculation unit 373 calculates the position of the beacon transmitter 359 (i.e., the position of the remote control device 350) relative to the vehicle center C based on any three of the four distances calculated above (for example, the first to third shortest distances). The vehicle center C is the position of the center of the vehicle (aerial work platform 301) in the vehicle length direction and vehicle width direction. Here, since the remote control position calculation unit 373 has the positions of the four beacon receivers 361 to 364 relative to the vehicle center C stored as known information, it can calculate the relative position of the beacon transmitter 359 (remote control device 350) relative to the vehicle center C using the so-called three-point positioning principle, based on the distance between the beacon transmitter 359 and each of the beacon receivers 361 to 364 (in this embodiment, any three of these distances). The position of the remote control device 350 can be represented, for example, by coordinates in an XY coordinate system where the vehicle center C is the origin, the vehicle width direction (left-right direction) is the X axis (positive to the right), and the vehicle length direction (front-to-back direction) is the Y axis (positive to the front).

[0126] The travel area calculation unit 374 calculates the predicted travel area SR in which the vehicle is expected to travel (pass through) based on the travel command signal transmitted by the operation control unit 371 to the travel control valve SV1, the steering angle γ of the front wheels 311a detected by the steering angle detector 309, and the known vehicle size. The travel command signal includes information on the forward and reverse direction of the vehicle 310 and the travel speed (low speed, medium speed, high speed). The steering angle γ of the steering wheels 311a is, as described above, the front wheels 311 'a' is the tilt angle, where the steering angle γ when the front wheel 311a tilts to the right is considered positive, and the steering angle γ when the front wheel 311a tilts to the left is considered negative. The vehicle size is information indicating the length, width, wheelbase (distance between front and rear wheels), and treadbase (distance between left and right wheels) of the aerial work platform 301, and is pre-stored in the memory area of ​​the controller 370. Based on this information, the travel area calculation unit 374 calculates the vehicle's direction of travel (direction of travel), turning center, turning radius, and the travel trajectory of each wheel 311 (311a, 311b) to derive a travel prediction area SR that extends in the direction of travel of the vehicle. The vehicle's direction of travel is the direction in which the vehicle moves, determined based on the vehicle's forward and backward direction and steering angle γ, etc.

[0127] Here, Figure 22 is a schematic diagram illustrating the vehicle's predicted movement region SR. Figure (A) shows the predicted movement region SR set when the vehicle is traveling at a low speed (forward right turn), and Figure (B) shows the predicted movement region SR set when the vehicle is traveling at a high speed (forward right turn). When the vehicle is moving forward right turn, the front wheel 311a on the outside in the turning direction (the front end of the vehicle on the outside in the turning direction) turns furthest out, and the rear wheel 311b on the inside in the turning direction (the rear end of the vehicle on the inside in the turning direction) turns furthest in. Therefore, the predicted movement region SR is formed between the travel trajectory K1 of the front wheel 311a on the outside in the turning direction and the travel trajectory K2 of the rear wheel 311b on the inside in the turning direction. As can be seen by comparing Figures 22(A) and (B), the width of this predicted movement region SR is set to be wider as the vehicle's speed increases and narrower as the vehicle's speed decreases. In other words, the predicted movement area SR is set wider when the vehicle is traveling at a higher speed than when it is traveling at a lower speed. The length of the predicted movement area SR may be a predetermined constant value (for example, three times the total length of the vehicle), or it may be a variable value that changes according to driving conditions such as the travel speed. The movement area calculation unit 374 generates (updates) the predicted movement area SR at each time interval in which it acquires an operation signal (input information) from the remote control device 350.

[0128] The position determination unit 375 determines whether the remote control device 350 is within the predicted vehicle movement area SR based on the position of the remote control device 350 calculated by the remote control position calculation unit 373 and the predicted vehicle movement area SR calculated by the movement area calculation unit 375. The presence of the remote control device 350 within the predicted vehicle movement area SR means that there is a worker (a worker operating the remote control device 350) ahead in the direction of the vehicle's movement. Therefore, the position determination unit 375 determines whether there is a worker (a worker operating the remote control device 350) ahead in the direction of the vehicle's movement.

[0129] The straight-line distance calculation unit 376 calculates the distance SD from the vehicle center C to the remote control device 350 (referred to as the "straight-line distance") based on the position of the remote control device 350 calculated by the remote control position calculation unit 373. This straight-line distance SD is the straight-line distance between the vehicle center C and the remote control device 350 in the plan view shown in Figure 22.

[0130] The determination value calculation unit 377 calculates a determination value (threshold) for determining when a vehicle approaches the remote control device 350, based on the output value of the driving command signal transmitted by the operation control unit 371 to the driving control valve SV1. In this embodiment, the output value of the driving command signal and the determination value are approximately proportional, and the larger the output value of the driving command signal to the driving control valve SV1 (i.e., the valve opening of the driving control valve SV1 and the driving speed of the driving motor 312), the larger the distance determination value is set to be.

[0131] The distance determination unit 378 determines whether the straight-line distance SD (straight-line distance SD from the vehicle center C to the remote control device 350) calculated by the straight-line distance calculation unit 376 is less than or equal to the determination value calculated by the determination value calculation unit 377. If the distance determination unit 378 determines that the straight-line distance SD is less than or equal to the determination value (straight-line distance SD ≤ determination value), it determines that the remote control device 350 (operator) is near the moving vehicle.

[0132] The regulating unit 379 transmits a regulating signal to the operation control unit 371 to regulate (stop) the operation of the vehicle 310, and transmits an alarm signal to the alarm device 380 to activate the alarm device 380, when the operation regulating unit 379 receives a regulating signal from the regulating unit 372, it determines that a driving operation is being performed, the position determination unit 375 determines that the remote control device 350 is within the predicted vehicle movement area SR, and the distance determination unit 378 determines that the straight-line distance SD from the vehicle center C to the remote control device 350 is less than or equal to a determination value. In addition, the operation regulating unit 379 transmits an alarm signal to the alarm device 380 to activate the alarm device 380. Regarding the operation regulating of the vehicle 310, the operation regulating unit 371 may be configured to impose an operation restriction on the operation control unit 371, such as by not accepting the operation signal when a driving operation (operation of the driving operation switch) is being performed when the operation regulating unit 379 receives a regulating signal from the regulating unit 379, or by not electromagnetically driving the driving control valve SV1 even if the operation regulating unit 371 accepts the operation signal.

[0133] The alarm device 380 consists of, for example, an alarm buzzer, an alarm lamp, a display monitor, and an audio speaker, and is designed to alert the worker by issuing an alarm in response to an alarm signal from the control unit 379 (an alarm to warn the worker that the operation of the mobile unit 310 has been restricted). This alarm device 380 includes all means that can alert the worker through sight, hearing, etc. Furthermore, since this alarm device 380 is installed in the remote control device 350, the above alarm signal is wirelessly transmitted from the control unit 379 to the alarm device 380 via the communication device 306. The alarm device 380 may also be installed on the mobile unit 310, the work platform 330, the upper operating device 340, etc.

[0134] Furthermore, the regulatory unit 379 may change the content of the alarm according to the straight-line distance SD (distance from the vehicle center C to the remote control device 350) calculated by the straight-line distance calculation unit 376. For example, the volume of the voice used for the alarm may be increased as the straight-line distance SD decreases, or the color of the lamp used for the alarm may be changed. In addition, the alarm operation of the alarm device 380 may be started before the driving operation of the vehicle 310 is restricted (stopped). For example, the alarm operation of the alarm device 380 may be started when the straight-line distance SD falls below a first determination value, and the driving operation of the vehicle 310 may be restricted (stopped) when the straight-line distance SD falls below a second determination value (provided that the second determination value < the first determination value).

[0135] Next, the driving restriction process performed in the safety device of the third embodiment will be described. Figure 23 is a flowchart showing the procedure for the driving restriction process performed in the safety device of the third embodiment.

[0136] First, in step S31, the driving operation determination unit 372 determines whether or not there is an operation input (operation signal input) from the driving operation switches (forward driving switch 351, reverse driving switch 352). If the driving operation determination unit 372 determines that there is an operation input from the driving operation switches (forward driving switch 351, reverse driving switch 352) (step S31: YES), it proceeds to step S32. On the other hand, if the driving operation determination unit 372 determines that there is no operation input from the driving operation switches (forward driving switch 351, reverse driving switch 352) (step S31: NO), it terminates the current process.

[0137] In step S32, the remote control position calculation unit 373 calculates the positional relationship between the vehicle and the remote control device 350 (the position of the remote control device 350 relative to the vehicle center C) based on the detected value (received radio wave strength) of the beacon receiver 360.

[0138] In step S33, the travel region calculation unit 374 calculates the predicted travel region SR of the vehicle based on the travel command signal transmitted by the operation control unit 371 to the travel control valve SV1, the steering angle γ of the front wheels (steering wheels) 11a detected by the steering angle detector 309, and the known vehicle size.

[0139] In step S34, the position determination unit 375 determines whether the remote control device 350 is within the predicted movement area SR based on the position of the remote control device 350 relative to the vehicle center C calculated in step S32 and the predicted movement area SR calculated in step S33. If the position determination unit 375 determines that the remote control device 350 is within the predicted movement area SR (step S34: YES), it proceeds to step S35. On the other hand, if the position determination unit 375 determines that the remote control device 350 is not within the predicted movement area SR (step S34: NO), it terminates the current process.

[0140] In step S35, the straight-line distance calculation unit 376 calculates the straight-line distance SD from the vehicle center C to the remote control device 350.

[0141] In step S36, the determination value calculation unit 377 calculates a determination value (threshold) based on the output value of the travel command signal transmitted by the operation control unit 371 to the travel control valve SV1.

[0142] In step S37, the distance determination unit 378 determines whether the straight-line distance SD calculated in step S35 is less than or equal to the determination value calculated in step S36. If the distance determination unit 378 determines that the straight-line distance SD is less than or equal to the determination value (step S37: YES), it proceeds to step S38. On the other hand, if the distance determination unit 378 determines that the straight-line distance SD is not less than or equal to the determination value (step S37: NO), it terminates the current process.

[0143] In step S38, the regulating unit 379 transmits a regulating signal to the operation control unit 371 to regulate (stop) the operation of the vehicle (driving body 310). The regulating unit 379 also wirelessly transmits an alarm signal to the alarm device 380 via the communication device 306 to activate the alarm device 380.

[0144] As described above, according to the safety device of the third embodiment, the position of the remote control device 350 is estimated as the position of the operator remotely operating the vehicle. When the remote control device 350 is located ahead of the vehicle's direction of travel, and the straight-line distance SD from the vehicle's center C to the remote control device 350 is less than or equal to a determination value, the vehicle's operation is restricted and an alarm is activated. This allows for accurate determination of the proximity between the vehicle and the remote control device 350 based on their relative positions and distance in the vehicle's direction of travel. As a result, it is possible to prevent the remotely operated vehicle from coming into contact with or colliding with the operator, thereby improving safety during remote operation.

[0145] Furthermore, according to the safety device of the third embodiment, by calculating a predicted movement area SR in which the vehicle 310 is expected to move, and determining whether or not the remote control device 350 is within this predicted movement area SR, it is possible to easily and accurately determine whether the remotely controlled vehicle is approaching the operator, thereby further improving safety during remote operation.

[0146] Furthermore, according to the safety device of the third embodiment, by varying the determination value for determining when the vehicle (driving body 310) approaches the remote control device 350 according to the driving speed, it becomes possible to more reliably prevent the remotely controlled vehicle from coming into contact with or colliding with an operator while suppressing excessive operation restrictions and / or alarm activation.

[0147] The present invention is not limited to the embodiments described above, and can be appropriately improved without departing from the spirit of the invention.

[0148] In the above embodiment, the remote control device is equipped with a beacon transmitter, and the vehicle is equipped with multiple beacon transmitters. While a beacon receiver is provided to detect the position and distance of the remote control device relative to the vehicle (turning center or vehicle center) based on the radio wave strength received by each beacon receiver from the beacon transmitter, the configuration is not limited to this. Alternatively, an RFID tag may be attached to the remote control device, and multiple RFID readers may be attached to the vehicle, and the position and distance of the remote control device relative to the vehicle (turning center or vehicle center) may be detected based on the radio wave strength received by each RFID reader from the RFID tag. Furthermore, as another variation, the position and distance of the remote control device relative to the vehicle (turning center or vehicle center) may be detected using non-contact sensors such as LiDAR (Light Detection and Ranging or Laser Imaging Detection and Ranging), ultrasonic sensors, infrared sensors, or radar sensors (millimeter-wave radar). Alternatively, the position and distance of the remote control device relative to the vehicle (turning center or vehicle center) may be detected by image processing using imaging devices such as monocular cameras, stereo cameras, or depth cameras.

[0149] In the above embodiment, a case in which a wireless remote control device is used was described, but the configuration is not limited to this, and a wired remote control device may also be used.

[0150] In the above embodiment, when the calculated distance (vertical distances BD1, BD2, SD) falls below a certain value, the operation of the boom or traveling body is restricted and an alarm is activated by the alarm device. However, the configuration is not limited to this, and when the calculated distance (vertical distances BD1, BD2, SD) falls below a certain value, only the operation of the boom or traveling body is restricted, or only an alarm is activated by the alarm device.

[0151] In the first and second embodiments described above, a hole-digging and pole-erecting vehicle was used as an example of a remotely operated work vehicle (a remotely operated work vehicle equipped with a boom), but other work vehicles such as a crane, bridge inspection vehicle, or rail-road vehicle may also be used.

[0152] In the third embodiment described above, a vertical lifting aerial work platform was used as an example of a remotely operated work vehicle (a self-propelled remotely operated work vehicle), but other work vehicles such as boom-type aerial work platforms or transport trolleys may also be used. Furthermore, in the third embodiment described above, an aerial work platform driven by a hydraulic travel motor (hydraulic actuator) was used as an example, but an aerial work platform driven by an electric travel motor (electric actuator) may also be used. In addition, the travel device of the aerial work platform is not limited to a wheeled travel device, but may be a crawler-type travel device. [Explanation of Symbols]

[0153] 1. Hole-digging and pole-erecting vehicle (remotely operated work vehicle) 2. Vehicle body (running body) 13 Boom 20 Auger device (working device) 30 Remote control device (remote operation device) 34 Alarm device 35. Beacon transmitter (position calculation unit) 50 Gripping device (work device) 100 controllers 101 Operation Control Unit 102 Operation Determination Unit (Operation Direction Calculation Unit) 103 Remote control position calculation unit (position calculation unit) 104 Passage area calculation unit (operation direction calculation unit) 105 Position determination section 106 Vertical distance calculation section (distance calculation section) 108 Distance determination unit 109 Regulatory Department 120 Boom attitude detector (boom attitude detection unit) 130 Beacon receiving device (position calculation unit) 200 controllers 202 Operation Determination Unit (Operation Direction Calculation Unit) 204 Passage area calculation unit (operation direction calculation unit) 205 Position determination section 206 Straight-line distance calculation unit (distance calculation unit) 208 Distance determination unit 209 Regulatory Department 301 Aerial work platform (remotely operated work vehicle) 310 Running body 320 Telescopic Post (Working Equipment) 330 Workbench (working equipment) 350 Remote control device (remote operation device) 359 Beacon transmitter (position calculation unit) 360 Beacon Receiver (Position Calculation Unit) 370 Controller 371 Operation Control Unit 373 Remote control position calculation unit (position calculation unit) 374 Progress area calculation unit (progress direction calculation unit) 375 Position determination section 376 Straight-line distance calculation unit (distance calculation unit) 378 Distance determination unit 379 Regulatory Department 380 alarm device BR1 Boom Passage Prediction Area BR2 Boom Passage Prediction Region SR Progression Prediction Area BD1 Vertical distance BD2 straight line distance SD Straight-line distance O Swivel center C Vehicle Center

Claims

1. A vehicle capable of moving, A boom is provided on the aforementioned traveling body so as to be able to rise and fall and rotate, A working device provided at the tip of the boom, A remote control device for remotely controlling the operation of the boom, An operation control unit that controls the operation of the boom based on the operation of the remote control device, A boom attitude detection unit for detecting the attitude of the boom, A position calculation unit that calculates the position of the remote control device, A distance calculation unit that calculates the distance between the boom and the remote control device, An operating direction calculation unit for calculating the operating direction of the boom, Based on the boom attitude detected by the boom attitude detection unit, a position determination unit determines whether the position of the remote control device calculated by the position calculation unit is ahead of the operating direction of the boom calculated by the operating direction calculation unit, A distance determination unit determines whether the distance between the boom and the remote control device calculated by the distance calculation unit is less than or equal to a predetermined determination value, A safety device for a remotely operated work vehicle, comprising: a position determination unit which determines that the position of the remote control device is ahead of the operating direction of the boom, and a distance determination unit which determines that the distance between the boom and the remote control device is less than or equal to the determination value, and a regulating unit which regulates the operation of the boom and / or activates an alarm.

2. The operating direction calculation unit calculates a predicted passage area in which the boom is expected to pass, based on the boom's posture. The safety device for a remotely operated work vehicle according to claim 1, characterized in that the position determination unit determines whether the position of the remotely operated device is ahead of the operating direction of the boom, based on whether the position of the remotely operated device calculated by the position calculation unit is within the predicted passage area calculated by the operating direction calculation unit.

3. The safety device for a remotely operated work vehicle according to claim 1 or 2, characterized in that the determination value is varied according to the operating speed of the boom.

4. A vehicle capable of moving, A work device provided on the aforementioned traveling body, A remote control device for remotely controlling the movement of the aforementioned moving body, An operation control unit that controls the movement of the traveling body based on the operation of the remote control device, A position calculation unit that calculates the position of the remote control device, A distance calculation unit that calculates the distance between the traveling body and the remote control device, A direction of travel calculation unit that calculates the direction of travel of the aforementioned traveling body, A position determination unit determines whether the position of the remote control device calculated by the position calculation unit is ahead of the direction of travel of the traveling body calculated by the direction of travel calculation unit, A distance determination unit determines whether the distance between the vehicle and the remote control device calculated by the distance calculation unit is less than or equal to a predetermined determination value, A safety device for a remotely operated work vehicle, characterized in that the position determination unit determines that the position of the remote control device is ahead of the direction of travel of the vehicle, and the distance determination unit determines that the distance between the vehicle and the remote control device is less than or equal to the determination value, and the regulating unit performs a regulating and / or alarm operation on the vehicle.

5. The aforementioned direction of travel calculation unit calculates a predicted travel region in which the traveling body is expected to travel based on the direction of travel of the traveling body, The safety device for a remotely operated work vehicle according to claim 4, characterized in that the position determination unit determines whether the position of the remotely operated device is ahead of the direction of travel of the vehicle, based on whether the position of the remotely operated device calculated by the position calculation unit is within the predicted travel area calculated by the direction of travel calculation unit.

6. The safety device for a remotely operated work vehicle according to claim 4 or 5, characterized in that the determination value is varied according to the travel speed of the traveling body.

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