EP4631903A1

EP4631903A1 - Crane device

Info

Publication number: EP4631903A1
Application number: EP23906687.1A
Authority: EP
Inventors: Mimori HARADA
Original assignee: Tadano Ltd
Current assignee: Tadano Ltd
Priority date: 2022-12-19
Filing date: 2023-12-04
Publication date: 2025-10-15
Also published as: WO2024135321A1; JP2024087440A

Abstract

[Problem] To provide a crane apparatus automatically performing an appropriate safety processing and having good usability.

[Solutions] A control program implemented on a controller of a crane apparatus obtains a lifting height L2 measured by a sensor and a payout length L1 that is a distance from a boom tip end portion to a suspended load (S12). The control program calculates a suspended-load height H that is a distance from a surveillance-target surface to the suspended load based on the lifting height L2 and the payout length L1 (S13). The control program sets a determination area based on the lifting height L2 and the suspended-load height H (S14). The control program generates determination image data for determining whether a human is captured, based on the set determination area and the surveillance image data. When obtaining a determination result indicating that a human is captured in a determination image indicated by the determination image data (S18 and S19: Yes), the control program stops driving of a winch or the like (S23).

Description

TECHNICAL FIELD

The present invention relates to a crane apparatus to which a surveillance camera is provided at a tip end portion of a boom.

BACKGROUND ART

Patent Document 1 discloses a crane apparatus including a surveillance camera. The surveillance camera is attached to a tip end portion of a boom and captures a suspended load and its surroundings. A surveillance video captured by the surveillance camera is displayed on a surveillance monitor installed in a cabin. An operator (pilot) operates the crane apparatus while watching the surveillance video.
In the crane apparatus described in Patent Document 1, an object surrounding a center portion of the surveillance video is displayed by superimposing on the surveillance video. The object is a circle having a vertical projection point of a hook as a center, and indicates a circular area having a predetermined radius (5 m) on the ground. The object is an area (attention area) that invokes an attention to the operator in order to ensure safety during a transportation work of the suspended load.

PRIOR ART DOCUMENT

PATENT DOCUMENT

Patent Document 1: Japanese Patent No. 7088432 Gazette

SUMMARY OF THE INVENTION

PROBLEMS TO BE SOLVED BY THE INVENTION

In the crane apparatus described in Patent Document 1, there is a risk that the operator overlooks a human captured in the attention area. Therefore, the inventors of the present application focus on a point that a determination whether a human is captured in the attention area is to be performed not by the operator but by a program (so-called human determining program). The inventors think that safety of the work can be further improved by making the crane apparatus automatically perform processing (safety processing), such as stopping of driving of the crane, when the human determining program determines that a human is captured in the attention area.
However, when automatic execution of the safety processing is adopted, following problems are expected to occur. Namely, if a target area (determination area) for determining whether a human is captured is set wider than a range (assumed range) where presence of a human is expected to cause a safety hazard to the work, the safety processing is executed although there is no safety hazard, and the crane apparatus stops during the work.
On the other hand, in a crane apparatus, a suspended-load hook may be moved near a working surface such as the ground before and after the transportation work of the suspended load. Thus, the inventors of the present application think that safety of the work should be improved by automatically performing the safety processing using the human determining program, also in moving the suspended-load hook near the working surface.
The present invention has been made considering the above-mentioned circumstances, and a first object thereof is to provide a crane apparatus automatically performing an appropriate safety processing and having improved usability. Furthermore, a second object of the present invention is to provide a crane apparatus capable of safely moving a suspended-load hook near a working surface (surveillance-target surface).

MEANS FOR SOLVING THE PROBLEMS

(1) A crane apparatus according to a first invention includes a boom capable of standing, lying, extending, and retracting, a winch provided at a base end portion side of the boom and capable of paying out and winding up a wire rope, a suspended-load hook connected to the wire rope, the wire rope paid out from the winch and hung around a tip end portion of the boom, a surveillance camera installed at the tip end portion of the boom and configured to capture an image downward to output surveillance image data, and a controller to which the surveillance image data is input. The controller is configured to execute a suspended-load height deciding processing of deciding a suspended-load height that is a distance from a surveillance-target surface to a suspended load suspended from the suspended-load hook, a determination area setting processing of setting an area of a part of a surveillance image indicated by the surveillance image data as a determination area for determining whether a human is captured, based on the suspended-load height and the surveillance image data, a result obtaining processing of obtaining a determination result whether a human is captured in the determination area, and a predetermined safety processing based on a fact that the determination result indicating that a human is captured in the determination area is obtained.
An assumed range where presence of a human is expected to cause a safety hazard to work becomes wider as a height of the suspended load becomes higher, and becomes narrower as the height of the suspended load becomes lower. The determination area for determining whether a human is captured is set in accordance with the suspended-load height that affects the assumed range so as to coincide with the assumed range. Therefore, the crane apparatus according to the first invention can appropriately set the determination area so as to coincide with the assumed range. As a result, the crane apparatus according to the first invention can automatically perform an appropriate safety processing and can improve usability.
(2) The crane apparatus according to the first invention may further include a wire length sensor configured to output a first measurement value in accordance with a payout length of the wire rope from the tip end portion of the boom, and a distance measuring sensor installed at the tip end portion of the boom and configured to output a second measurement value in accordance with a distance from the tip end portion to the surveillance-target surface. The suspended-load height deciding processing is a processing of calculating the suspended-load height based on the payout length indicated by the first measurement value and a distance indicated by the second measurement value.
The suspended-load height is calculated based on the first measurement value output by the wire length sensor and the second measurement value output by the distance measuring sensor. Therefore, the suspended-load height can be decided regardless of a height position of the surveillance-target surface or a height position of a crane installation surface. As a result, the determination area can be set appropriately in any working environment.
(3) The crane apparatus according to the first invention may further include a wire length sensor configured to output a first measurement value in accordance with a payout length of the wire rope from the tip end portion of the boom, a boom length sensor configured to output a third measurement value in accordance with a length of the boom, a derricking angle sensor configured to output a fourth measurement value in accordance with a derricking angle of the boom, and a suspended-load load sensor configured to output a fifth measurement value in accordance with a load applied to the wire rope by the suspended load. The suspended-load height deciding processing includes a first obtaining processing of obtaining the first measurement value, the third measurement value, and the fourth measurement value at a predetermined time point when the load indicated by the fifth measurement value changes from zero or becomes zero, a processing of calculating a relative height indicating a difference in height between a crane installation surface and the surveillance-target surface, based on the first measurement value, the third measurement value, and the fourth measurement value that are obtained in the first obtaining processing, and a processing of calculating the suspended-load height based on the relative height, and the first measurement value, the third measurement value, and the fourth measurement value that are newly obtained.
A time point when the load applied to the wire rope by the suspended load changes from zero indicates a time point when the suspended load lefts the surveillance-target surface (so-called hoisting a grounded load) because of winding up of the wire rope. A time point when the load becomes zero indicates a time point when the suspended load lands on the surveillance-target surface because of winding down of the wire rope. The controller calculates the relative height in accordance with a difference between the crane installation surface and the surveillance-target surface based on the first measurement value, the third measurement value, and the fourth measurement value at the predetermined time point. The controller calculates the suspended-load height based on the calculated relative height, and the first measurement value, the third measurement value, and the fourth measurement value that are newly obtained. Therefore, the suspended-load height can be decided regardless of the height position of the surveillance-target surface or the height position of the crane installation surface. As a result, the determination area can be set appropriately in any working environment.
(4) The crane apparatus according to the first invention may further include a wire length sensor configured to output a first measurement value in accordance with a payout length of the wire rope from the tip end portion of the boom, a boom length sensor configured to output a third measurement value in accordance with a length of the boom, a derricking angle sensor configured to output a fourth measurement value in accordance with a derricking angle of the boom, and an input device configured to receive an input of a relative height indicating a difference between a crane installation surface and the surveillance-target surface. The suspended-load height deciding processing is a processing of calculating the suspended-load height based on the relative height, the first measurement value, the third measurement value, and the fourth measurement value.
The suspended-load height is calculated based on the first measurement value output by the wire length sensor, the third measurement value output by the boom length sensor, the fourth measurement value output by the derricking angle sensor, and the relative height input by an operator. Therefore, the determination area can be set appropriately in any working environment.
(5) The suspended-load height deciding processing may include a processing of deciding the suspended-load height based on a size of a specific object captured in the surveillance image and a threshold size or a calculation formula prestored in a memory.
The suspended-load height is decided based on the size of the specific object captured in the surveillance image and the threshold size prestored in the memory. Therefore, the suspended-load height can be decided regardless of the height position of the surveillance-target surface or the height position of the crane installation surface. As a result, the determination area can be set appropriately in any working environment.
(6) An angle of view of the surveillance camera may be constant. The controller is configured to further execute a camera height deciding processing of deciding a camera height that is a distance from the surveillance-target surface to the surveillance camera. The determination area setting processing is a processing of setting the determination area further based on the camera height.
When the angle of view of the surveillance camera is constant, a capturing range is changed in accordance with the camera height. The determination area is set further based on the camera height that affects the capturing range. Therefore, even if a camera having a constant angle of view is used as the surveillance camera, the determination area can be set appropriately.
(7) The controller may include a computer, and a memory configured to store a control program that causes the computer to execute the suspended-load height deciding processing, the determination area setting processing, the result obtaining processing, and the safety processing, and a human determining program that causes the computer to execute a human determining processing of determining whether a human is captured and a processing of outputting a determination result. The determination area setting processing includes a processing of generating determination image data based on the suspended-load height and the surveillance image data. The result obtaining processing includes a processing of passing the determination image data to the human determining program, and a processing of receiving the determination result from the human determining program.
The control program generates the determination image data from the surveillance image data based on the suspended-load height, passes the generated determination image data to the human determining program, and receives the determination result from the human determining program. For example, a human determining program fostered through deep learning is installed on the crane apparatus and is used.
(8) The controller may be configured to further execute a camera height deciding processing of deciding a camera height that is a distance from the surveillance-target surface to the surveillance camera. The determination area setting processing includes an amplitude deciding processing of deciding an amplitude of a swing of the suspended load based on the camera height and the surveillance image data, and is a processing of setting the determination area based on the amplitude.
As the amplitude of the swing of the suspended load becomes larger, the assumed range where the presence of a human is assumed to cause a safety hazard to work becomes wider. The crane apparatus according to the first invention decides the amplitude of the swing of the suspended load based on the camera height and the surveillance image data, and sets the determination area based on the decided amplitude. Therefore, the determination area can be set more appropriately.
(9) A crane apparatus according to a second invention includes a slewing base, a boom mounted on the slewing base and capable of standing, lying, extending, and retracting, a winch provided at a base end portion side of the boom and capable of paying out and winding up a wire rope, a suspended-load hook connected to the wire rope, the wire rope paid out from the winch and hung around a tip end portion of the boom, a surveillance camera installed at the tip end portion of the boom and configured to capture an image downward to output surveillance image data, an operating device configured to receive a slewing operation of the slewing base and a derricking operation and an extending/retracting operation of the boom, and a controller to which the surveillance image data is input. The controller is configured to execute a hook height deciding processing of deciding a hook height that is a distance from a surveillance-target surface to the suspended-load hook, a hook height determining processing of determining whether the hook height is less than a threshold height prestored in a memory, a trajectory estimating processing of estimating a movement trajectory of the suspended-load hook until a predetermined time passes based on a movement direction and a movement speed indicated respectively by the slewing operation, the derricking operation, and the extending/retracting operation, based on a fact that the hook height is less than the threshold height, a determination area setting processing of setting a part of an area of an image indicated by the surveillance image data as a determination area for determining whether a human is captured, based on the surveillance image data and the movement trajectory, a result obtaining processing of obtaining a determination result whether a human is captured in the determination area, and a predetermined safety processing based on a fact that the determination result indicating that a human is captured in the determination area is obtained.
The threshold height is set to a value in accordance with a height of a human. Namely, in the hook height determining processing, it is determined whether the suspended-load hook is at a height where there is a risk of collision with a human. When determined that the suspended-load hook is at the height where there is the risk of collision with the human, the movement trajectory of the suspended-load hook until the predetermined time passes is estimated based on the movement direction and the movement speed indicated by an operation received by the operating device. Then, it is determined whether the human is captured in the determination area including the estimated movement trajectory. When determined that the human is captured in the determination area, the predetermined safety processing is executed. Therefore, the crane apparatus according to the second invention can safely move the suspended-load hook near the surveillance-target surface (working surface).
(10) The crane apparatus according to the second invention may further include a suspended-load load sensor configured to output a measurement value in accordance with a load applied to the wire rope by the suspended load. The controller is configured to execute the hook height deciding processing, the trajectory estimating processing, the determination area setting processing, the result obtaining processing, and the safety processing, based on a fact that the load indicated by the measurement value is zero.

A series of processing such as the hook height deciding processing is executed only when the suspended load is not suspended.

EFFECTS OF THE INVENTION

The crane apparatus according to the present invention can automatically perform an appropriate safety processing and can improve usability. Furthermore, the crane apparatus according to the present invention can safely move a suspended-load hook near a working surface.

BRIEF DESCRIPTION OF THE DRAWINGS

Fig. 1 is a side view of a crane vehicle 10 in a state where a boom 22 stands up.
Fig. 2 is a functional block diagram of a crane apparatus 12.
Fig. 3 is a diagram showing an operating device 29 in a cab 13.
Fig. 4 is a diagram showing a capturing area and an assumed range according to a first embodiment.
Fig. 5 is a diagram showing a capturing area and an assumed range according to the first embodiment.
Fig. 6 is a flowchart of a surveillance processing according to the first embodiment.
Fig. 7 is a diagram showing a capturing area and an assumed range according to a first modification example of the first embodiment.
Fig. 8 is a diagram showing a capturing area and an assumed range according to the first modification example of the first embodiment.
Fig. 9 is a flowchart of a surveillance processing according to the first modification example of the first embodiment.
Fig. 10 is a diagram showing a capturing area and an assumed range according to a second modification example of the first embodiment.
Fig. 11 is a flowchart of a surveillance processing according to the second modification example of the first embodiment.
Fig. 12 is a diagram showing a capturing area and an assumed range according to a third modification example of the first embodiment.
Fig. 13 is a flowchart of a surveillance processing according to the third modification example of the first embodiment.
Fig. 14 is a flowchart of a surveillance processing according to a fourth modification example of the first embodiment.
Fig. 15(A) is a diagram showing a capturing area according to a second embodiment, and Fig. 15(B) is an explanatory diagram for explaining an estimated movement trajectory and a determination area.
Fig. 16 is a flowchart of a surveillance processing according to the second embodiment.

MODES FOR CARRYING OUT THE INVENTION

Hereinafter, an embodiment of the present invention will be described. Note that it goes without saying that each embodiment described below is merely an example of the present invention, and each embodiment can be modified as appropriate without departing from the gist of the present invention. For example, an execution order of each processing described later can be changed as appropriate without departing from the gist of the present invention. Or, a part of processing described later may be omitted as appropriate without departing from the gist of the present invention.

[First embodiment]

In the present embodiment, a crane vehicle 10 shown in Fig. 1 will be described. The crane vehicle 10 is a rough terrain crane. However, the crane vehicle 10 may be an all terrain crane.
The crane vehicle 10 includes a traveling body 11, an outrigger device 14 attached to the traveling body 11, and a crane apparatus 12 and a cab 13 that are mounted on the traveling body 11.
The outrigger device 14 has a plurality of jacks 18 that contact the ground to stabilize a posture of the crane vehicle 10. The crane apparatus 12 is used in a state where the jacks 18 are extended and the posture of the crane vehicle 10 is stabilized.
The crane apparatus 12 has a slewing base 21, a boom 22, a winch 23, a group of sensors 26 (see Fig. 2), a group of hydraulic actuators 27 (see Fig. 2), a hydraulic pressure supplying device 28 (see Fig. 2), an operating device 29 (see Fig. 2), a control monitor 80 (see Fig. 2), a hook block 32, a surveillance camera 17, and a controller 70 (see Fig. 2).
The slewing base 21 is slewably held by the traveling body 11. The boom 22 is supported by the slewing base 21 so as to be able to stand and lie. The boom 22 is configured by arranging a plurality of cylindrical bodies in a nested manner to form a so-called telescopic structure, and can extend and retract. Namely, the boom 22 is capable of standing, lying, extending, retracting, and slewing. The boom 22 stands up and lies down between a lie-down position substantially along a horizontal direction and a stand-up position substantially along a vertical direction. The crane vehicle 10 travels in a state where the boom 22 is retracted and laid down (so-called "a stowed state").
The winch 23 is attached to a base end of the boom 22 or the slewing base 21. The winch 23 has a drum 56 around which a wire rope 41 (hereinafter denoted as "wire 41") is wound, and a sheave 57 around which the wire 41 is hung. The wire 41 is wound to the drum 56 or rolled out from the drum 56 by driving the winch 23.
The wire 41 is hung around the sheave 57 provided at a base end portion of the boom 22, a sheave 58 provided at a tip end portion of the boom 22, and a pulley device (not shown). The pulley device has a plurality of first sheaves (not shown) provided at the tip end portion of the boom 22 and a plurality of second sheaves (not shown) provided to a hook block 32.
The hook block 32 includes a hook body 33, the plurality of second sheaves (not shown) rotatably held in the hook body 33, and a hook 34 provided at a lower surface of the hook body 33.
The number of times that the wire 41 is hung around the first sheaves and the second sheaves is a so-called "number of hanging wires". As the number of hanging wires is larger, increased is a maximum suspended-load weight that is a maximum value of load that the crane apparatus 12 can suspend. Namely, as the number of hanging wires is larger, a load-suspending capacity of the crane apparatus 12 is increased. Note that in the example shown in Fig. 1, four wires 41 are visually recognizable in a pseudo manner between the tip end portion of the boom 22 and the hook block 32, and the number of hanging wires is "4". The number of hanging wires is input to the controller 70 via the later-described control monitor 80 (see Fig. 2), for example, and is stored in a memory 72 (see Fig. 2). The number of hanging wires is used to calculate a payout length L1 (see Fig. 4) that is a distance from the tip end portion of the boom 22 to a suspended load 35.
Two winches 23 may be provided to the crane apparatus 12. The hook block 32 that is a so-called main hook is connected to the wire 41 of one winch 23, and a subhook (not shown) is connected to the wire 41 of the other winch 23. The hook block 32 and the subhook correspond to "a suspended-load hook" recited in the claims.
As shown in Fig. 2, the crane apparatus 12 includes the group of hydraulic actuators 27. The group of hydraulic actuators 27 includes a slewing motor 51, a derricking cylinder 52, an extending/retracting cylinder 53, and a hydraulic motor 54.
The slewing motor 51 is a hydraulic motor that rotates via hydraulic oil supplied from the hydraulic pressure supplying device 28, and makes the slewing base 21 slew. The derricking cylinder 52 is a hydraulic cylinder that extends and retracts via the hydraulic oil supplied from the hydraulic pressure supplying device 28, and makes the boom 22 stand or lie. The extending/retracting cylinder 53 is a hydraulic cylinder that extends and retracts via the hydraulic oil supplied from the hydraulic pressure supplying device 28, and makes the boom 22 extend and retract. The hydraulic motor 54 rotates via the hydraulic oil supplied from the hydraulic pressure supplying device 28, and makes the drum 56 of the winch 23 rotate.
The hydraulic pressure supplying device 28 includes a hydraulic pump driven by an engine 15 mounted on the traveling body 11, pipes that connect the hydraulic pump with the slewing motor 51 or the like of the group of hydraulic actuators 27, a hydraulic pressure switching valve and the like provided to the pipes and the like. The hydraulic pressure switching valve may be a so-called electromagnetic valve, and is driven by a drive signal input from the controller 70. By driving the electromagnetic valve, the slewing motor 51, the derricking cylinder 52, the extending/retracting cylinder 53, and the hydraulic motor 54 are driven. Namely, the controller 70 can make the boom 22 slew, stand, lie, extend, and retract, and wind up or pay out the wire 41 by outputting the drive signals.
The group of sensors 26 has a slewing angle sensor 61, a boom length sensor 62, a derricking angle sensor 63, a drum sensor 64, and a distance measuring sensor 65. Note that a suspended-load load sensor 66 shown by a broken line in Fig. 2 will be described in a first modification example.
The slewing angle sensor 61 outputs, as a measurement value, a physical quantity in accordance with a slewing angle of the slewing base 21 from a slewing reference position. The slewing reference position is a position of a state where the boom 22 in the stowed state protrudes forward. The slewing angle sensor 61 is a rotary encoder provided to a rotation axis of the slewing base 21, for example. The slewing angle sensor 61 outputs, as the measurement value, the number of pulse signals in accordance with the slewing angle of the slewing base 21.
The boom length sensor 62 outputs, as a measurement value, a physical quantity in accordance with a length of the boom 22. The boom length sensor 62 may be a sensor that outputs a measurement value indicating the length of the boom 22, may be a sensor that outputs a measurement value indicating an extension length of the extending/retracting cylinder 53, or may be a sensor that outputs a measurement value indicating driving time of the extending/retracting cylinder 53. The measurement value output by the boom length sensor 62 corresponds to "a third measurement value" recited in the claims.
The derricking angle sensor 63 outputs, as a measurement value, a physical quantity in accordance with a derricking angle of the boom 22. The derricking angle sensor 63 is an inclination sensor that outputs an angle with respect to a horizontal surface or a horizontal sensor, for example. Or, the derricking angle sensor 63 is a sensor that outputs a measurement value indicating an extension length or driving time of the derricking cylinder 52. The measurement value output by the derricking angle sensor 63 corresponds to "a fourth measurement value" recited in the claims.
The drum sensor 64 outputs, as a measurement value, a physical quantity in accordance with a payout length of the wire 41 from the winch 23. The drum sensor 64 is a rotary encoder attached to an axis of the drum 56, for example. The drum sensor 64 outputs pulse signals in accordance with rolling out and winding up of the wire 41. The number of pulses per unit time indicates a rotation speed of the drum 56, namely, a payout speed or a windup speed of the wire 41, and the total number of pulses indicates an amount of rotation of the drum 56, namely, the payout length or a windup length of the wire 41. The drum sensor 64 corresponds to "a wire length sensor" recited in the claims. The pulse signals output by the drum sensor 64 correspond to "a first measurement value" recited in the claims.
The distance measuring sensor 65 is attached to the tip end portion of the boom 22, and takes downward as a detection area. The distance measuring sensor 65 is a laser distance measuring sensor that measures a distance by irradiating laser light vertically downward and receiving reflected light reflected by the surveillance-target surface (working surface). Or, the distance measuring sensor 65 may be an acoustic wave sensor or an electric wave sensor that measures a distance by outputting an acoustic wave or an electric wave and receiving a reflected wave reflected by the surveillance-target surface. The measurement value output by the distance measuring sensor 65 corresponds to "a second measurement value" recited in the claims.
In the following, description is made with the measurement value output by the sensor, such as the slewing angle sensor 61, the boom length sensor 62, the derricking angle sensor 63, the drum sensor 64, or the distance measuring sensor 65, being also described as "a sensor measurement value".
As shown in Fig. 1, the surveillance camera 17 is provided at the tip end portion of the boom 22, and takes a lower portion of the tip end portion as a capturing area. For example, the surveillance camera 17 has a wide-angle lens that always takes the lower portion of the tip end portion of the boom 22 as the capturing area irrespective of the derricking angle of the boom 22. Or, a direction changing mechanism that changes a direction of the surveillance camera 17 in accordance with the derricking angle of the boom 22 is provided at the tip end portion of the boom 22. In the following, description is made assuming that the boom 22 is provided with a direction changing mechanism that always makes lenses of the surveillance camera 17 direct downward by a self-weight of the surveillance camera 17.
The surveillance camera 17 has a plurality of imaging elements that detect light collected by the lenses. The imaging element is a CCD, a CMOS, or the like. Each imaging element outputs pixel data, respectively. The pixel data is data indicating a color or the like, and is 8-bit data, for example. The surveillance camera 17 generates image data based on the pixel data, and outputs the generated image data. Note that the image data includes pixel position data indicating positions of pixels and a resolution in addition to the pixel data. In the following, description is made with the image data output by the surveillance camera 17 being described as "surveillance image data", and an image indicated by the surveillance image data being described as "a surveillance image". The surveillance image may be a still image, or may be a single frame constituting a video.
The slewing angle sensor 61, the boom length sensor 62, the derricking angle sensor 63, the drum sensor 64, and the distance measuring sensor 65 of the group of sensors 26, and the surveillance camera 17 are connected to the controller 70 by signal lines (not shown). Namely, the sensor measurement values output by the slewing angle sensor 61 and the like, and the surveillance image data output by the surveillance camera 17 are input to the controller 70. However, the surveillance camera 17 may be wirelessly connected to the controller 70. In this case, a battery and a sending antenna are attached to the surveillance camera 17, and a receiving antenna connected to the controller 70 by signal lines or the like is installed in the cab 13. The surveillance camera 17 captures an image using power supplied from the battery, and sends surveillance screen data from the sending antenna. The sent surveillance image data is received by the receiving antenna, and is input to the controller 70.
Each sensor such as the slewing angle sensor 61 continuously performs detection at a predetermined time interval (so-called sampling period/sampling cycle), and outputs the sensor measurement value at the predetermined time interval. Furthermore, the surveillance camera 17 continuously captures images at a predetermined time interval, and outputs the surveillance image data at the predetermined time interval.
Fig. 3 is a diagram showing the operating device 29 in the cab 13.
As shown in Fig. 3, the operating device 29 is arranged in the cab 13. The operating device 29 includes operating levers, foot pedals, operating buttons, and the like that are operated by an operator, the control monitor 80, and a surveillance monitor 84.
The operating device 29 is connected to the controller 70 by signal lines (not shown). The operator operates the operating device 29 to input instructions to the controller 70, and operates the crane apparatus 12.
As shown in Fig. 2, the control monitor 80 includes a display 81, a transparent sheet-like touch sensor 82 overlaid on the display 81, and a speaker 83. Namely, the control monitor 80 is a so-called "AML". The operator inputs various information such the number of hanging wires by using the touch sensor 82. Note that the speaker 83 may be provided separately from the control monitor 80. For example, the speaker 83 that issues a notice to the outside of the crane vehicle 10 may be provided to the crane apparatus 12. The control monitor 80 or the touch sensor 82 corresponds to "an input device" recited in the claims.
The surveillance monitor 84 is a monitor that displays the surveillance image or a later-described determination image that is an image obtained by processing the surveillance image.
Note that the crane vehicle 10 may include a remote-control device (not shown) in addition to the operating device 29 or in place of the operating device 29. For example, the remote-control device includes a touch panel, input buttons, input levers, or the like that receive an input from the operator, and an antenna that sends out an operation signal in accordance with an input operation of the operator. The operation signal sent out by the remote-control device is received by an antenna installed in the cab 13 or the like of the crane vehicle 10, and is input to the controller 70. However, the controller 70 itself may be incorporated in the remote-control device. The remote-control device is an example of "an input device" recited in the claims.
The controller 70 includes a CPU 71 that is a central arithmetic processing unit, the memory 72, a power supply circuit 74, and a communication bus (not shown). The controller 70 is realized by ICs, a microcomputer, resistors, diodes, capacitors, and the like implemented on a control board. The control board is arranged in a control box arranged in the cab 13, for example. The CPU 71 corresponds to "a computer" recited in the claims. Note that a communication interface 73 and a management server 100 shown by broken lines will be described in other modification examples.
The CPU 71, the memory 72, the hydraulic pressure supplying device 28, the slewing angle sensor 61 and the like of the group of sensors 26, the surveillance camera 17, and the operating device 29 are connected to the communication bus (not shown). A later-described control program 75 executed by the CPU 71 reads out data and information from the memory 72, makes the memory 72 store data and information, and controls driving of the group of hydraulic actuators 27. Furthermore, the control program 75 obtains the sensor measurement values output by the group of sensors 26, the surveillance image data output by the surveillance camera 17, and the inputs made by the operator to the operating device 29.
The memory 72 prestores an OS 77 that is an operating system, and the control program 75 and a human determining program 76 that are executed by the CPU 71. Furthermore, the memory 72 prestores object data, warning sound data, a calculation formula, a correspondence table, an angle of view ϕ, and various constants. The object data is data indicating characters and figures for warnings or the like that are displayed in a superimposed manner on the image captured by the surveillance camera. The warning sound data is data that indicates an alarm sound or a warning voice. The angle of view ϕ is a constant indicating a viewing angle of the surveillance camera 17. The calculation formula, the correspondence table, and the constants are used to generate determination image data in a later-described surveillance processing. A determination table shown by a broken line will be described in a later-described third modification example, and a threshold height K shown by a broken line will be described in a later-described second embodiment.
The control program 75 is a program that controls driving of the group of hydraulic actuators 27 and the like based on the operation signals input from the operating device 29, and executes the later-described surveillance processing (see Fig. 6).
The human determining program 76 is a program that determines whether a human is captured in an image. The human determining program 76 is a program fostered through learning such as deep learning. The human determining program 76 simplifies image data by a binarization processing, for example, extracts a plurality of external shape lines, and determines whether a human is captured in the image based on whether the extracted external shape lines coincide with or approximate a specific pattern indicating a human. The learning means optimizing a kind of the specific pattern, a range of an approximation, or the like. Note that the above-described human determining method is an example, and the human determining program 76 may determine whether a human is captured in the image by other methods.
The power supply circuit 74 converts a DC voltage supplied from a battery 16 mounted on the traveling body 11 into a DC voltage having a predetermined voltage value, such as 5V, 12V, or 24V, and outputs the converted DC voltage. The power supply circuit 74 is realized by a power supply IC that is a DC/DC converter, capacitors, resistors, diodes, coils, and the like. Note that the battery 16 is charged by the engine 15 of the traveling body 11. The DC voltage output by the power supply circuit 74 is supplied to the CPU 71, the operating device 29, the group of sensors 26, the surveillance camera 17, and the like. In Fig. 2, power supply lines from the power supply circuit 74 to the group of sensors 26 and the like are omitted.
Figs. 4 and 5 are diagrams showing a capturing area where the surveillance camera 17 captures an image, and an assumed range where presence of a human is assumed to cause a safety hazard to work. Fig. 4 shows a case where the surveillance-target surface is a dig-down surface that is lower than the crane installation surface. Fig. 5 shows a case where the surveillance-target surface is a construction surface or a rooftop surface that is higher than the crane installation surface. Furthermore, Figs. 4(A) and 5(A) show cases where the suspended load 35 is at a relatively low height position, and Figs. 4(B) and 5(B) show cases where the suspended load 35 is at a relatively high height position.
An "angle ϕ" shown in Figs. 4 and 5 indicates the angle of view (viewing angle) of the surveillance camera 17. Note that in the present embodiment, an example in which the surveillance camera 17 having a constant angle of view ϕ irrespective of the height is used will be described.
A "capturing area" shown in Figs. 4 and 5 indicates an area where the surveillance camera 17 captures an image. Note that since the angle of view ϕ is constant, as a position of the tip end portion of the boom 22 becomes higher, the capturing area becomes wider.
A "payout length L1" shown in Figs. 4 and 5 indicates a distance from the tip end portion of the boom 22 to the suspended load 35.
A "lifting height L2" shown in Figs. 4 and 5 indicates a distance from the tip end portion of the boom 22 to the surveillance-target surface (working surface). The lifting height L2 corresponds to "a camera height" recited in the claims.
A "suspended-load height H" shown in Figs. 4 and 5 indicates a distance from the surveillance-target surface to the suspended load 35. The suspended-load height H is a distance obtained by subtracting the payout length L1 from the lifting height L2.
Fig. 6 is a flowchart of a surveillance processing executed by the control program 75 of the controller 70.
Hereinafter, the surveillance processing will be described. Note that processing executed by the control program 75 is also processing executed by the controller 70 or the CPU 71.
The control program 75 starts the surveillance processing shown in Fig. 6, for example, based on a fact that the operating device 29 is powered on, or based on a fact that the operator makes a specific input to the operating device 29 or the control monitor 80.
In the surveillance processing, the control program 75 obtains the surveillance image data output by the surveillance camera 17 (S11). Furthermore, the control program 75 obtains the sensor measurement values output by each sensor such as the slewing angle sensor 61 (S12). The processing of step S12 of obtaining the lifting height L2 measured by the distance measuring sensor 65 corresponds to "a camera height deciding processing" recited in the claims.
The control program 75 calculates the suspended-load height H that is the distance from the surveillance-target surface to the suspended load 35, based on the sensor measurement values obtained in step S12 (S13). To describe in detail, the control program 75 calculates the payout length L1 (see Figs. 4 and 5) that is the distance from the tip end portion of the boom 22 to the suspended load 35, based on the number of hanging wires stored in the memory 72 and the measurement value measured by the drum sensor 64. For example, the control program 75 calculates the payout length L1 by calculating a total payout length of the wire 41 from the tip end portion of the boom 22 based on the number of the pulses output by the drum sensor 64 and dividing the calculated total payout length by the number of hanging wires. Note that in the following, description is made with the payout length L1 calculated based on the length measured by the drum sensor 64 and the number of hanging wires being simply described as "a payout length L1 measured by the drum sensor 64" or "a payout length L1".
The control program 75 calculates the suspended-load height H by subtracting the payout length L1 from the lifting height L2 (see Figs. 4 and 5) measured by the distance measuring sensor 65. The processing of step S13 corresponds to "a suspended-load height deciding processing" recited in the claims.
The control program 75 decides a determination area for determining whether a human is captured, based on the lifting height L2 obtained in step S12 and the suspended-load height H calculated in step S13 (S14). To describe in detail, the memory 72 prestores the calculation formula (see Fig. 2) for deciding the determination area. The calculation formula outputs a number sequence of pixels indicating the determination area. The calculation formula outputs the number sequence of pixels indicating the determination area, when the lifting height L2 and the suspended-load height H are input. Note that the number sequence also indicates the resolution. For example, for the surveillance image data with a resolution of 800 × 800, a range with a resolution of 50 × 50 is set as the determination image data.
In this manner, the determination area is decided based on the lifting height L2 indicating the height of the surveillance camera 17 and the suspended-load height H. Namely, the determination area is decided to be an appropriate range in accordance with the height of the surveillance camera 17 and in accordance with the suspended-load height.
Note that in place of the calculation formula, the correspondence table (see Fig. 2) in which the number sequence of pixels, the lifting height L2, and the suspended-load height H are associated may be prestored in the memory 72.
The control program 75 generates the determination image data that is a target for determining whether a human is captured, based on the number sequence indicating the determination area decided in step S14 and the surveillance image data obtained in step S11 (S15). To describe in detail, the control program 75 generates the determination image data by selecting pixel data indicated by the number sequence decided in step S14 from among a plurality pieces of pixel data included in the surveillance image data, and assigning new pixel numbers to the selected pixel data or rearranging them.
Note that when the shape of the assumed range is "circle", the control program 75 may process the shape of the determination image indicated by the determination image data into "rectangle" in a pseudo manner by adding pixel data indicating white to the selected pixel data, for example. Namely, even if the assumed range is "rectangle" or "circle", the determination image data indicating a rectangular determination image is generated. The processing of steps S14 and S15 corresponds to "a determination area setting processing" recited in the claims.
The control program 75 passes the determination image data generated in step S15 to the human determining program 76 via the OS 77, and instructs the human determining program 76 to determine whether a human is captured in the determination image indicated by the determination image data (S16). The processing of step S16 corresponds to "a processing of passing" recited in the claims.
The human determining program 76 determines whether a human is captured in the determination image indicated by the passed determination image data (S17). The human determining program 76 returns a first determination result indicating that no human is captured, or a second determination result indicating that a human is captured, to the control program 75 via the OS 77. In addition to information indicating that a human is captured, the second determination result includes position information indicating an area determined to be the human in the determination image. The first determination result indicating that no human is captured is a determination flag having a value of "0", for example, and information indicating that a human is captured is the determination flag having a value of "1". The position information is a number sequence of pixels indicating a boundary of an area where a human is captured, for example. The processing of step S17 corresponds to "a human determining processing" recited in the claims.
The control program 75 receives the determination result output by the human determining program 76 (S18). The processing of steps S16 and S18 corresponds to "a result obtaining processing" recited in the claims. The processing of step S18 corresponds to "a processing of receiving" recited in the claims.
Based on the received determination result, the control program 75 determines whether a human is captured in the determination image, namely, whether a human exists in the assumed range (S19). Specifically, the control program 75 determines whether the value of the determination flag included in the received determination result is "0" or "1". When determining that no human exists in the assumed range (S19: No), the control program 75 outputs the determination image data generated in step S15 or the surveillance image data obtained in step S11 to the surveillance monitor 84 (S20). As a result, the determination image or a surveillance video is displayed on the surveillance monitor 84.
When determining that a human exists in the assumed range (S19: Yes), the control program 75 outputs the determination image data or the surveillance image data, emphasis object data, warning object data read out from the memory 72, and arrangement position information to the surveillance monitor 84 (S21). The emphasis object data is data indicating a circle, an ellipse, a rectangle, or the like that surrounds a human captured in the determination image indicated by the determination image data. The warning object data is characters indicating a warning, such as "There is a human. Please be careful.", for example. The arrangement position information is information indicating a position where the circle, the ellipse, or the rectangle indicated by the emphasis object data is arranged. The control program 75 generates the arrangement position information based on the position information included in the determination result obtained in step S18.
Furthermore, the control program 75 outputs the warning sound data stored in the memory to the speaker 83, causing the speaker 83 to output the alarm sound or the warning voice (S22). The alarm sound or the warning voice may be audible only to the operator in the cab, or may be audible to a human around the crane vehicle 10.
Furthermore, the control program 75 forcibly stops driving of all or a part of the winch 23, the boom 22, and the slewing base 21 (S23).
The processing of step S21 of making the surveillance monitor 84 display an emphasis object or a warning object, the processing of step S22 of making the speaker 83 output the alarm sound or the warning voice, and the processing of step S23 forcibly stopping driving of all or a part of the winch 23, the boom 22, and the slewing base 21 all correspond to "a safety processing" recited in the claims.
Note that only one processing among the processing of the steps S21 of making the surveillance monitor 84 display the emphasis object and the warning object, the processing of S22, and the processing of S23 may be executed as the safety processing.
The control program 75 determines whether the surveillance processing is to be finished (S24). For example, the control program 75 finishes the surveillance processing based on an input to power off the operating device 29 or a fact that a specific input is made to the operating device 29. When determining that the surveillance processing is not to be finished (S24: No), the control program 75 executes processing of and after step S11 again. The processing of and after step S11 repeatedly performed is performed at a time interval (sampling periods) of several tens of milliseconds to several seconds, for example. When determining that the surveillance processing is to be finished (S24: Yes), the control program 75 finishes the surveillance processing (END).

[Actions and effects of first embodiment]

When an object falls, a falling point fluctuates more in case of falling from a high position. Namely, the assumed range where presence of a human is assumed to cause a safety hazard to work becomes wider as the height of the suspended load becomes higher. On the other hand, if the determination area for determining whether a human is captured is made too wide with taking a safety margin, although safety increases, a warning is issued or a forcible stop is executed even in a case where the work can be done safely in spite of an existence of the human, which decreases usability of the crane apparatus 12. In the present embodiment, the determination area for determining whether a human is captured is set in accordance with the suspended-load height H so as to coincide with the assumed range (S14). Therefore, the crane apparatus 12 according to the present embodiment can automatically perform an appropriate safety processing and can improve usability of the crane apparatus 12.
In the present embodiment, the lifting height L2 and the suspended-load height H required for generating the determination image data are calculated based on the measurement values output by the drum sensor 64 and the distance measuring sensor 65 (S12, S13). Therefore, the determination image data can be generated irrespective of whether the surveillance-target surface is a dig-down surface (see Fig. 4) or a construction surface (see Fig. 5), and irrespective of whether the crane installation surface is the ground surface.
In the present embodiment, the determination area is decided also based on the height of the surveillance camera 17 (lifting height L2) in addition to the suspended-load height H (S14). Therefore, even if the surveillance camera 17 having a constant angle of view ϕ is used, the determination area can be set appropriately.
In the present embodiment, the control program 75 passes the determination image data to the human determining program 76 (S16), and receives the determination result from the human determining program 76 (S18). Therefore, the human determining program 76 fostered through deep learning or the like can be incorporated into the controller 70 as a module and can be used. Furthermore, the human determining program 76 incorporated into the controller 70 can be updated using a new human determining program fostered through deep learning or the like. Namely, a version up of the human determining program 76 can be performed easily.

[First modification example of first embodiment]

In the present modification example, described is an example in which the crane apparatus 12 includes a suspended-load load sensor 66 (see Fig. 2) in place of the distance measuring sensor 65. Note that configurations and processing other than those described below are the same as those described in the first embodiment. The same symbols are attached to the same configurations and processing as those in the first embodiment, and descriptions thereof are omitted.
The suspended-load load sensor 66 measures a physical quantity in accordance with a load applied to the wire 41 by the suspended load 35. The suspended-load load sensor 66 is a hydraulic sensor that measures a hydraulic pressure supplied to the derricking cylinder 52, for example. The memory 72 prestores a calculation formula for calculating the load applied to the wire 41 by the suspended load 35, based on the boom length measured by the boom length sensor 62, the derricking angle measured by the derricking angle sensor 63, and the hydraulic pressure measured by the hydraulic sensor that is the suspended-load load sensor 66. Or, the memory 72 prestores a correspondence in which the boom length measured by the boom length sensor 62, the derricking angle measured by the derricking angle sensor 63, the hydraulic pressure measured by the hydraulic sensor that is the suspended-load load sensor 66, and the load applied to the wire 41 by the suspended load 35 are associated. The load applied to the wire 41 by the suspended load 35 is calculated using the calculation formula or the correspondence table. In other words, the hydraulic pressure measured by the hydraulic sensor that is the suspended-load load sensor 66 is "a physical quantity in accordance with the load applied to the wire 41 by the suspended load 35". The measurement value output by the suspended-load load sensor 66 corresponds to "a fifth measurement value" recited in the claims.
Note that the suspended-load load sensor 66 may be a tension meter that directly measures the load applied to the wire 41 by the suspended load 35, a load cell, a pressure sensor that measures the hydraulic pressure supplied to the winch 23, or the like.
The memory 72 prestores a constant D (see Figs. 7 and 8). The constant D is a height from a tire to the base end of the boom 22.
Fig. 7(A) shows a state where the surveillance-target surface (working surface) is a dig-down surface that is lower than the ground surface and the suspended load 35 contacts the surveillance-target surface. Fig. 7(B) shows a state where the surveillance-target surface (working surface) is the dig-down surface and the crane apparatus 12 suspends the suspended load 35 and is working.
Fig. 8(A) shows a state where the surveillance-target surface (working surface) is a construction surface or a rooftop surface that is higher than the ground surface and the suspended load 35 contacts the surveillance-target surface. Fig. 8(B) shows a state where the surveillance-target surface (working surface) is the construction surface or the rooftop surface and the crane apparatus 12 suspends the suspended load 35 and is working. The construction surface is a topmost surface of a building under construction, and the rooftop surface is a rooftop of a building.
A "payout length L1a" shown in Figs. 7(A) and 8(A) is a distance from the surveillance-target surface to the tip end portion of the boom 22 in a state where the suspended load 35 contacts the surveillance-target surface. On the other hand, a "payout length L1b" shown in Figs. 7(B) and 8(B) is a distance from the tip end portion of the boom 22 to the suspended load 35 during work, and is a value that changes moment by moment.
"θa" shown in Figs. 7(A) and 8(A) is a derricking angle of the boom 22 in the state where the suspended load 35 contacts the surveillance-target surface. On the other hand, "θb" shown in Figs. 7(B) and 8(B) is a derricking angle of the boom 22 during work, and is a value that changes moment by moment.
A "boom length L3a" shown in Figs. 7(A) and 8(A) is a length of the boom 22 in the state where the suspended load 35 contacts the surveillance-target surface. On the other hand, a "boom length L3b" shown in Figs. 7(B) and 8(B) is a length of the boom 22 during work, and is a value that changes moment by moment.
A "relative height E" shown in Figs. 7 and 8 is a distance from the surveillance-target surface to the crane installation surface.
Fig. 9 is a flowchart of a surveillance processing executed in the present modification example. In the present modification example, the controller 70 (control program 75) executes the surveillance processing shown in Fig. 9 in place of the surveillance processing shown in Fig. 6.
In the surveillance processing, the control program 75 obtains the surveillance image data output by the surveillance camera 17 (S11). Furthermore, the control program 75 obtains the suspended-load load measured by the suspended-load load sensor 66 and makes the memory 72 store it (S31). The control program 75 executes the processing of step S31 periodically at a predetermined sampling period. An area for storing at least two suspended-load loads are set to the memory 72.
The control program 75 compares the latest suspended-load load stored in the memory 72 with the suspended-load load previously stored in the memory 72, and determines whether the suspended-load load is changed (S32). The suspended-load load is changed from zero to plus at a moment when the wire 41 is wound up in a state where the suspended load 35 contacts the surveillance-target surface. Furthermore, the suspended-load load is changed from plus to zero at a moment when the wire 41 is wound down and the suspended load 35 contacts the surveillance-target surface in a state where the suspended load 35 does not contact the surveillance-target surface.
When determining that the suspended-load load is changed (S32: Yes), the control program 75 obtains the sensor measurement values (S33). Specifically, the payout length L1a, the boom length L3a, and the derricking angle θa shown in Figs. 7(A) and 8(A) are obtained. The control program 75 calculates the relative height E based on the payout length L1a, the boom length L3a, and the derricking angle θa that are obtained. Specifically, the control program 75 calculates E = L3a * sin θa + D - L1a. "*" in the calculation formula means a multiplication. The calculation formula is prestored in the memory 72. Note that when the surveillance-target surface is a dig-down surface (see Fig. 7(A)), the relative height E becomes a negative value, and when the surveillance-target surface is a construction surface (see Fig. 8(A)), the relative height E becomes a positive value. The moment when it is determined that the suspended-load load is changed (S32: Yes) corresponds to "a predetermined time point" recited in the claims. The processing of step S33 corresponds to "a first obtaining processing" recited in the claims.
As shown in Fig. 9, the control program 75 makes the memory 72 store the calculated relative height E (S34). The processing of step S34 corresponds to "a processing of calculating the relative height" recited in the claims.
On the other hand, when determining that the suspended-load load is not changed (S32: No), the control program 75 skips the processing of steps S33 and S34.
Next, the control program 75 obtains the sensor measurement values again (S35). The sensor measurement values obtained in step S35 are the measurement values during work, and are the payout length L1b, the boom length L3b, and the derricking angle θb shown in Figs. 7(B) and 8(B).
As shown in Fig. 9, the control program 75 calculates the suspended-load height H and the lifting height L2 using the sensor measurement values obtained in step S35 and the relative height E stored in the memory 72 in step S34 (S36). Specifically, the control program 75 calculates the suspended-load height H = (D - E) + L3b * sin θb - L1b (see Figs. 7(B) and 8(B)). Furthermore, the control program 75 calculates the lifting height L2 by adding the payout length L1b obtained in step S35 to the calculated suspended-load height H (S36). A portion of calculating the suspended-load height H in step S36 corresponds to "a suspended-load height deciding processing" recited in the claims. A portion of calculating the lifting height L2 in step S36 corresponds to "a camera height deciding processing" recited in the claims.
The control program 75 executes the processing from steps S14 to S24 using the suspended-load height H and the lifting height L2 calculated in step S36.

[Actions and effects of first modification example of first embodiment]

In the present modification example, the lifting height L2 and the suspended-load height H required for generating the determination image data are calculated based on the measurement values output by the boom length sensor 62, the derricking angle sensor 63, the drum sensor 64, and the suspended-load load sensor 66 (steps S31 to S36). Therefore, the determination image data can be generated irrespective of whether the surveillance-target surface is a dig-down surface (see Fig. 7), or is a construction surface or a rooftop surface (see Fig. 8), and irrespective of whether the crane installation surface is the ground surface.

[Second modification example of first embodiment]

In the first modification example, described is an example in which the relative height E (see Figs. 7 and 8) is calculated based on the measurement values output by the boom length sensor 62, the derricking angle sensor 63, the drum sensor 64, and the suspended-load load sensor 66. In the present modification example, described is an example in which an operator inputs the relative height E (see Fig. 10) using the touch sensor 82 of the control monitor 80 (so-called AML). Note that configurations and processing other than those described below are the same as those described in the first embodiment or the first modification example. The same symbols are attached to the same configurations and processing as those in the first embodiment or the first modification example, and descriptions thereof are omitted.
Note that in the present modification example, the crane apparatus 12 does not include the distance measuring sensor 65.
Fig. 10(A) shows a case where the surveillance-target surface is a dig-down surface that is lower than the crane installation surface. Fig. 10(B) shows a case where the surveillance-target surface is a construction surface or a rooftop surface and is higher than the crane installation surface. Fig. 11 is a flowchart of a surveillance processing executed in the present modification example. In the present modification example, the controller 70 (control program 75) executes the surveillance processing shown in Fig. 11 in place of the surveillance processing shown in Fig. 6.
The operator inputs, via the control monitor 80, the relative distance E that is the distance between the surveillance-target surface and the crane installation surface. Note that for example, the operator inputs a negative value as the relative height E when the surveillance-target surface is lower than the crane installation surface (Fig. 10(A)), and inputs a positive value as the relative height E when the surveillance-target surface is higher than the crane installation surface (Fig. 10(B)). Note that the operator may input, to the control monitor 80, a distance from the ground surface to the surveillance-target surface and a distance from the ground surface to the crane installation surface in place of inputting the relative height E. In this case, the control program 75 calculates the relative height E based on the distance from the ground surface to the surveillance-target surface and the distance from the ground surface to the crane installation surface that are input. Namely, values input by the operator may be any values if the relative height E can be calculated with the input values.
The control program 75 determines whether an input of the relative height E is received (S41). When determining that the input of the relative height E is received (S41: Yes), the control program 75 makes the memory 72 store the input relative height E (S42). On the other hand, when determining that the input of the relative height E is not received (S41: No), the control program 75 skips the processing of step S42.
Thereafter, the control program 75 executes the processing of steps S11, S35, S36, and steps S14 to S24.

[Actions and effects of second modification example of first embodiment]

In the present modification example, the lifting height L2 and the suspended-load height H required for generating the determination image data are calculated based on the measurement values output by the boom length sensor 62, the derricking angle sensor 63, and the drum sensor 64, and the relative distance E input by the operator. Therefore, the determination image data can be generated irrespective of whether the surveillance-target surface is a dig-down surface (see Fig. 10(A)), or is a construction surface or a rooftop surface (see Fig. 10(B)), and irrespective of whether the crane installation surface is the ground surface.
Furthermore, the determination image data can be generated without providing the distance measuring sensor 65.

[Third modification example of first embodiment]

In the present modification example, described is an example in which the lifting height L2 is decided based on a size of a specific object captured in the surveillance image and a determination table (see Fig. 2) prestored in the memory 72. Note that configurations and processing other than those described below are the same as those described in the first embodiment. The same symbols are attached to the same configurations and processing as those in the first embodiment, and descriptions thereof are omitted.
In the determination table, a plurality of threshold ranges and the lifting height L2 are associated respectively. The size of the specific object is obtained, and the lifting height L2 is decided depending on which threshold range the obtained size belongs to. Lower limits and upper limits of the threshold ranges correspond to "a threshold size" recited in the claims.
Note that in the present modification example, the crane apparatus 12 does not include the distance measuring sensor 65.
Fig. 12(A) shows a case where the surveillance-target surface is a dig-down surface that is lower than the crane installation surface. Fig. 12(B) shows a case where the surveillance-target surface is a construction surface or a rooftop surface and is higher than the crane installation surface. Fig. 13 is a flowchart of a surveillance processing executed in the present modification example. In the present modification example, the controller 70 (control program 75) executes the surveillance processing shown in Fig. 13 in place of the surveillance processing shown in Fig. 6.
In the surveillance processing, the control program 75 obtains the surveillance image data output by the surveillance camera 17 (S11). The control program 75 determines whether a specific object is captured in the surveillance image indicated by the surveillance image data (S51). The specific object is "a human" such as a worker performing slinging or the like, or "a marker" having a predetermined size and placed on the surveillance-target surface.
Processing performed by the control program 75 in step S51 when the specific object is a human will be specifically described. The control program 75 at first passes the surveillance image data to the human determining program 76 via the OS 77, and receives the determination result from the human determining program 76. The control program 75 determines that the specific object is captured in the surveillance image, based on a fact that the determination result that a human is captured in the surveillance image is obtained (S51: Yes).
Processing performed by the control program 75 in step S51 when the specific object is a marker will be specifically described. The control program 75 obtains boundary line information from the surveillance image data obtained in step S11 using luminance difference, brightness difference, color difference, or the like. The control program 75 determines whether each shape surrounded by the boundary lines indicated by the obtained boundary line information coincides with or approximates a shape prestored as the shape of the marker in the memory 72. The control program 75 determines that the specific object is captured in the surveillance image when the shape surrounded by the boundary lines coincides with or approximates the shape prestored in the memory 72 (S51: Yes).
The control program 75 decides or calculates the size of the specific object (S52) based on a fact that it is determined that the specific object is captured in the surveillance image (S51: Yes). Specifically, when the specific object is a human, the control program 75 decides a size of the human shown in the surveillance image based on the position information included in the determination result received from the human determining program 76. When the specific object is a marker, the control program 75 calculates a size of the shape that is determined to coincide with or approximate, based on the boundary line information.
The control program 75 decides the lifting height L2 based on the size of the specific object decided or calculated in step S52 and the determination table stored in the memory 72, and makes the memory 72 store the lifting height L2 (S53).
The control program 75 obtains the payout length L1 (see Fig. 12) measured by the drum sensor 64 (S12). The control program 75 calculates the suspended-load height H (see Fig. 12) by subtracting the payout length L1 obtained in step S12 from the lifting height L2 stored in the memory 72 in step S53 (S13). Thereafter, the control program 75 executes the processing from steps S14 to S24.

[Actions and effects of third modification example of first embodiment]

In the present modification example, the lifting height L2 and the suspended-load height H required for generating the determination image data are calculated based on the measurement value output by the drum sensor 64 and the surveillance image data. Therefore, the determination image data can be generated irrespective of whether the surveillance-target surface is a dig-down surface (see Fig. 12 (A)), or is a construction surface or a rooftop surface (see Fig. 12 (B)), and irrespective of whether the crane installation surface is the ground surface.
Furthermore, the determination image data can be generated without providing the distance measuring sensor 65.
Note that the memory 72 may prestore a calculation formula for outputting the lifting height L2 when the size of the specific object is input, in place of the determination table.

[Fourth modification example of first embodiment]

In the present modification example, described is an example in which an amplitude F of a swing of the suspended load 35 is calculated based on the surveillance image data, and the determination area is decided further based on the calculated amplitude F. Note that configurations and processing other than those described below are the same as those described in the first embodiment. The same symbols are attached to the same configurations and processing as those in the first embodiment, and descriptions thereof are omitted.
Fig. 14 is a flowchart of a surveillance processing executed in the present modification example. In the present modification example, the controller 70 (control program 75) executes the surveillance processing shown in Fig. 14 in place of the surveillance processing shown in Fig. 6.
In the surveillance processing, the control program 75 obtains the surveillance image data output by the surveillance camera 17, the payout length L1 measured by the drum sensor 64, and the lifting height L2 measured by the distance measuring sensor 65 (S11, S12). Note that in step S11, the surveillance image data is repeatedly obtained in a term equal to or longer than a period of the swing of the suspended load 35.
The control program 75 respectively obtains boundary line information indicating boundary lines between the suspended load 35 and a background in each of a plurality pieces of the surveillance image data obtained in step S11. The control program 75 calculates an amount of change of the boundary lines (for example, the number of pixels) based on the obtained boundary line information, and calculates an amplitude F0 of a swing in the surveillance image based on the amount of change (S61). The processing of step S61 corresponds to "an amplitude deciding processing" recited in the claims.
The control program 75 calculates an actual amplitude F of the swing of the suspended load 35 based on the calculated amplitude F0, the resolution of the surveillance camera 17, the angle of view ϕ, and the lifting height L2 (S62). Specifically, the control program 75 calculates F = F0 * L2tan ϕ * (1/resolution) * 1/2. The calculation formula is prestored in the memory 72. The processing of step S62 corresponds to "an amplitude deciding processing" recited in the claims. Note that when the surveillance camera 17 having a constant angle of view is used, the angle of view ϕ is prestored in the memory 72 as a constant.
The control program 75 calculates the suspended-load height H based on the payout length L1 and the lifting height L2 that are obtained in step S12 (S13). The control program 75 sets the determination area based on the lifting height L2 (height of the surveillance camera 17) obtained in step S12, the suspended-load height H calculated in step S13, and the amplitude F calculated in step S63 (S63). To describe in detail, a calculation formula for outputting the number sequence of pixels when the lifting height L2, the suspended-load height H, and the amplitude F are input is prestored in the memory 72. The control program 75 obtains the number sequence of pixels indicating the determination area by inputting the lifting height L2, the suspended-load height H, and the amplitude F to the calculation formula. The control program 75 generates the determination image data indicating the determination area based on the obtained number sequence and the surveillance image data.
The control program 75 executes the processing from steps S16 to S24 based on the determination image data generated in step S15.

[Actions and effects of fourth modification example of first embodiment]

A falling point of an object is roughly decided in accordance with a height and a horizontal component of a speed at the time of falling start. The height at the time of falling start is the suspended-load height H. The horizontal component of the speed at the time of falling start is a value in accordance with the amplitude F of the swing. In the present modification example, since the determination area is set based on the amplitude F of the swing of the suspended load 35 and the suspended-load height H, the determination area can be set more appropriately.
Note that if the amplitude F0 in the surveillance image is calculated as a value using the resolution, the amplitude F can be calculated without using the resolution. The value using the resolution is 0.015 times the resolution, for example.
Note that in the present modification example, the lifting height L2 and the suspended-load height H may be calculated or decided by the methods described in the first to third modification examples.
Furthermore, in the present modification example, if the angle of view of the surveillance camera 17 is changed in accordance with the lifting height L2 (height of the surveillance camera 17) and an imaging range is constant, the amplitude F is calculated by F = F0 * A/2 * (1/resolution) * 1/2. Namely, when the surveillance camera 17 that changes the angle of view to keep the capturing range constant is used, the angle of view ϕ is unnecessary for calculating the amplitude F.

[Second embodiment]

In a crane work, the hook block 32 may be moved horizontally along the surveillance-target surface to a position where a load is loaded (slinging position). In the present embodiment, described is the crane apparatus 12 capable of improving safety during such crane work. Note that configurations and processing other than those described below are the same as those described in the first embodiment. The same symbols are attached to the same configurations and processing as those in the first embodiment, and descriptions thereof are omitted.
The memory 72 prestores a threshold height K shown in Fig. 2. The threshold height K is a value in accordance with a height of a human, and is set to a value obtained by adding a safety margin to the height of the human. The threshold height K is set within a range of 2.5 m to 3 m, for example.
The group of sensors 26 includes the slewing angle sensor 61, the boom length sensor 62, the derricking angle sensor 63, the drum sensor 64, the distance measuring sensor 65, and the suspended-load load sensor 66.
Fig. 15(A) is a diagram showing a state where a height of the hook block 32 (hereinafter, "hook height Q") is equal to or less than the threshold height K. The hook height Q is a distance from the surveillance-target surface to a lowest point of the hook block 32.
Fig. 15 (B) is an explanatory diagram showing, on the surveillance image, an estimated movement trajectory of the hook block 32 from the current time to 0.2 seconds later, and the determination area (assumed range) for determining whether a human is captured. In Fig. 15(B), the position of the hook block 32 at the current time is shown by a dot located at a center of the surveillance image. The position of the hook block 32 after 0.2 seconds is shown by a dot located in an upper left portion of the surveillance image. The estimated movement trajectory is shown by a solid line (curve) connecting the two dots. A boundary of the determination area is shown by a broken line.
Fig. 16 is a flowchart showing a surveillance processing executed by the controller 70 (control program 75).
Hereinafter, the surveillance processing will be described. Note that in the following, although the surveillance processing is described as being executed by the control program 75, the processing executed by the control program 75 is also processing executed by the controller 70 or the CPU 71.
The control program 75 obtains the surveillance image data output by the surveillance camera 17 and the sensor measurement values output by the group of sensors 26, respectively (S11, S12). The control program 75 determines whether the suspended-load load is zero or a value close to zero based on the suspended-load load measured by the suspended-load load sensor 66 (S71). Namely, the control program 75 determines whether the boom 22 is suspending the suspended load 35. When determining that the suspended-load load is not zero and that the suspended load 35 is suspended (S71: No), the control program 75 executes the surveillance processing described in the first embodiment and each modification example (see Figs. 6, 9, 11, 13, and 14). Namely, during a transportation of the suspended load 35, the surveillance processing described in the first embodiment and each modification example is executed, and before and after the transportation of the suspended load 35, processing of and after step S72 of the surveillance processing described in the present embodiment is executed.
When determining that the suspended-load load is zero and that the suspended load 35 is not suspended (S71: Yes), the control program 75 calculates the hook height Q based on the sensor measurement values obtained in step S12 (S72). Specifically, the control program 75 calculates the hook height Q by subtracting the payout length L1 from the lifting height L2 measured by the distance measuring sensor 65. The processing of step S72 corresponds to "a hook height deciding processing" recited in the claims.
The control program 75 determines whether the hook height Q calculated in step S72 is less than the threshold height K stored in the memory 72 (S73). Namely, in step S73, it is determined whether the hook block 32 is at a height that may cause a collision with a human. The processing of step S73 corresponds to "a hook height determining processing" recited in the claims.
When determining that the hook height Q is less than the threshold height K (S73: Yes), the control program 75 obtains an amount of operation of the operating device 29 operated by the operator (S74). The operation of the operator includes a slewing operation to instruct slewing of the slewing base 21, a derricking operation to instruct derricking of the boom 22, and an extending/retracting operation to instruct extension and retraction of the boom 22. The amount of operation of the operating device 29 is a depression amount of a control pedal, a direction and a move amount of a control lever, whether an operation button is operated, or the like. Namely, in step S74, the direction and the speed of slewing, derricking, and extending/retracting of the boom 22 are obtained. The direction and the speed of slewing, derricking, and extending/retracting of the boom 22 correspond to "a movement direction and a movement speed" recited in the claims.
The control program 75 calculates the estimated movement trajectory of the hook block 32 from the current time until a predetermined time passes (for example, after 0.2 seconds) based on the amount of operation obtained in step S74 (S75). The control program 75 calculates the estimated movement trajectory by synthesizing (calculating) a slewing vector indicating slewing of the slewing base 21, a derricking vector indicating derricking of the boom 22, and an extending/retracting vector indicating extending/retracting of the boom 22, for example. Note that a calculation formula and a coordinate system used for synthesis (calculation) are prestored in the memory 72. An origin of the coordinate system is a center position of the surveillance image that becomes a starting point of the estimated movement trajectory, for example. The processing of step S75 corresponds to "a trajectory estimating processing" recited in the claims.
The control program 75 sets the determination area based on the estimated movement trajectory calculated in step S75 (S76). For example, the memory 72 prestores a calculation formula for outputting the number sequence of pixels indicating the determination area when a formula indicating the estimated movement trajectory or a group of coordinate points is input. The control program 75 obtains the number sequence of pixels indicating the determination area using the calculation formula and the estimated movement trajectory. The processing of step S76 corresponds to "a determination area setting processing" recited in the claims.
The control program 75 generates the determination image data in a manner similar to the first embodiment based on the surveillance image data obtained in step S11 and the determination area set in step S76 (S77).
The control program 75 executes the processing of step S16 of passing the generated determination image data to the human determining program 76 and following processing. On the other hand, when determining that the hook height Q is not less than the threshold height K (S73: No), the control program 75 skips the processing from steps S74 to S23.
When determining that the surveillance processing is not to be finished (S24: No), namely, when determining that driving of the crane apparatus 12 is continuously performed, the control program 75 executes the processing of and after step S11 again. Namely, the surveillance image data is obtained at a predetermined time interval (sampling period), and processing such as determining the hook height (S73), calculating the estimated movement trajectory (S75), generating the determination image data (S77), determining whether a human exists (S19), and the safety processing (S21, S22, S23) are performed.

[Actions and effects of second embodiment]

In the present embodiment, when determined that the hook block 32 is at a height where there is a risk of collision with a human, the estimated movement trajectory of the hook block 32 until a predetermined time passes is calculated based on the operation amount received by the operating device 29. Then, it is determined whether a human is captured in the determination area including the calculated estimated movement trajectory. When determined that a human is captured in the determination area, the safety processing (S21, S22, S23) is executed. Therefore, the crane apparatus 12 can safely move the hook block 32 near the surveillance-target surface (working surface).
In the present embodiment, a series of processing of step S72 of calculating the hook height Q and following processing is executed only when the suspended load 35 is not suspended. Therefore, a processing load on the CPU 71 can be reduced compared to a case where the processing of and after step S72 is always executed.

[Modification example of second embodiment]

In the second embodiment, described is an example in which the distance measuring sensor 65 is provided to the crane apparatus 12 and the lifting height L2 and the hook height Q are calculated using the distance measuring sensor 65. However, the distance measuring sensor 65 may not necessarily be provided to the crane apparatus 12. In this case, the control program 75 may calculate the lifting height L2 or the hook height Q based on the measurement value output by the suspended-load load sensor 66, based on the relative height E input by the operator, or based on the surveillance image data, in a similar manner to each modification example of the first embodiment.

[Other modification examples of first embodiment and second embodiment]

In the first embodiment, the second embodiment, and each modification example, described is an example in which the angle of view ϕ of the surveillance camera 17 is constant and the determination image data is generated using the suspended-load height H and the lifting height L2 (S14, S15). However, if the angle of view is changed in accordance with the lifting height L2 (height of the surveillance camera 17) and the capturing area is always within a constant range, the determination image data may be generated based on the suspended-load height H without using the lifting height L2. In this case, a calculation formula for outputting the number sequence of pixels when the suspended-load height H is input is stored in the memory 72.
In the first embodiment, the second embodiment, and each modification example, explained is an example in which the human determining program 76 is implemented on the controller 70. However, the human determining program 76 may be implemented on a management server 100 shown in Fig. 2. The management server 100 is a so-called WEB server connected to the Internet 101. In this case, the controller 70 includes a communication interface 73 connectable to the Internet 101. A vehicle connectable to the Internet 101 is also called "a connected car". In step S16 of the surveillance processing, the control program 75 sends an HTTP request including the determination image data to the management server 100 via the communication interface 73 and the Internet 101. The management server 100 makes the human determining program determine whether a human is captured in the determination image indicated by the received determination image data. The management server 100 returns, to the crane apparatus 12, an HTTP response including the determination result output by the human determining program. In step S18, the control program 75 obtains the determination result returned by the management server 100. The processing of the control program 75 for receiving the HTTP response including the determination result corresponds to "a result obtaining processing" recited in the claims.
In the first embodiment, the second embodiment, and each modification example, the control program 75 may execute an update processing of the human determining program 76. The control program 75 sends, via the communication interface 73 and the Internet 101, an HTTP request including a request to return the human determining program and a version of the current human determining program 76, to the management server 100 that trains the human determining program. The management server 100 that receives the HTTP request returns, to the crane apparatus 12, an HTTP response including a new version of the human determining program. The control program 75 of the crane apparatus 12 that receives the HTTP response updates the currently implemented human determining program 76 with the new version of the human determining program included in the HTTP response.
In the first embodiment, the second embodiment, and each modification example, described is an example in which the surveillance monitor 84 is provided to the cab 13 and the determination image or the surveillance image is shown in the surveillance monitor 84. However, since the safety processing (S21, S22, S23) is executed automatically, the surveillance monitor 84 may not necessarily be provided.
In the first embodiment, the second embodiment, and each modification example, described is an example in which the payout length L1 of the wire 41 measured by the drum sensor 64 is the distance from the tip end portion of the boom 22 to the lowest point of the suspended load 35. However, the payout length L1 of the wire 41 measured by the drum sensor 64 may be a distance from the tip end portion of the boom 22 to the lowest point of the hook block 32, or may be a distance from the tip end portion of the boom 22 to a highest point of the hook block 32. The control program 75 adjusts the payout length L1 of the wire 41 by adding or subtracting a length of the hook block 32 or a distance from the lowest point of the hook block 32 to a lowest end of the suspended load 35 to/from the payout length L1 of the wire 41 measured by the drum sensor 64, and uses the adjusted value.
In the first modification example and the second embodiment, description is made assuming that the suspended-load load sensor 66 outputs the measurement value in accordance with the load applied to the wire 41 by the suspended load 35. However, the suspended-load load sensor 66 may output a measurement value in accordance with the load applied to the wire 41 by the suspended load 35 and the hook block 32. In this case, the control program 75 calculates the load applied to the wire 41 by the suspended load 35 by subtracting the load applied to the wire 41 by the hook block 32 from the load measured by the suspended-load load sensor 66. The load applied to the wire 41 by the hook block 32 is prestored in the memory 72.

DESCRIPTION OF REFERENCE CHARACTERS

10: crane vehicle
11: traveling body
12: crane apparatus
13: cab
17: surveillance camera
21: slewing base
22: boom
23: winch
26: group of sensors
29: operating device
32: hook block
34: hook
35: suspended load
41: wire rope
61: slewing angle sensor
62: boom length sensor
63: derricking angle sensor
64: drum sensor
65: distance measuring sensor
66: suspended-load load sensor
70: controller
71: CPU
72: memory
75: control program
76: human determining program
80: control monitor
81: display
82: touch sensor
83: speaker
84: surveillance monitor
100: management server
101: Internet

Claims

A crane apparatus comprising:
a boom capable of standing, lying, extending, and retracting;

a winch provided at a base end portion side of the boom and capable of paying out and winding up a wire rope;

a suspended-load hook connected to the wire rope, the wire rope paid out from the winch and hung around a tip end portion of the boom;

a surveillance camera installed at the tip end portion of the boom and configured to capture an image downward to output surveillance image data; and

a controller to which the surveillance image data is input, wherein

the controller is configured to execute:
a suspended-load height deciding processing of deciding a suspended-load height that is a distance from a surveillance-target surface to a suspended load suspended from the suspended-load hook;

a determination area setting processing of setting an area of a part of a surveillance image indicated by the surveillance image data as a determination area for determining whether a human is captured, based on the suspended-load height and the surveillance image data;

a result obtaining processing of obtaining a determination result whether a human is captured in the determination area; and

a predetermined safety processing based on a fact that the determination result indicating that a human is captured in the determination area is obtained.
The crane apparatus according to claim 1, further comprising:
a wire length sensor configured to output a first measurement value in accordance with a payout length of the wire rope from the tip end portion of the boom; and

a distance measuring sensor installed at the tip end portion of the boom and configured to output a second measurement value in accordance with a distance from the tip end portion to the surveillance-target surface, wherein

the suspended-load height deciding processing is a processing of calculating the suspended-load height based on the payout length indicated by the first measurement value and a distance indicated by the second measurement value.
The crane apparatus according to claim 1, further comprising:
a wire length sensor configured to output a first measurement value in accordance with a payout length of the wire rope from the tip end portion of the boom;

a boom length sensor configured to output a third measurement value in accordance with a length of the boom;

a derricking angle sensor configured to output a fourth measurement value in accordance with a derricking angle of the boom; and

a suspended-load load sensor configured to output a fifth measurement value in accordance with a load applied to the wire rope by the suspended load, wherein

the suspended-load height deciding processing includes:
a first obtaining processing of obtaining the first measurement value, the third measurement value, and the fourth measurement value at a predetermined time point when the load indicated by the fifth measurement value changes from zero or becomes zero;

a processing of calculating a relative height indicating a difference in height between a crane installation surface and the surveillance-target surface, based on the first measurement value, the third measurement value, and the fourth measurement value that are obtained in the first obtaining processing; and

a processing of calculating the suspended-load height based on the relative height, and the first measurement value, the third measurement value, and the fourth measurement value that are newly obtained.
The crane apparatus according to claim 1, further comprising:
a wire length sensor configured to output a first measurement value in accordance with a payout length of the wire rope from the tip end portion of the boom;

a boom length sensor configured to output a third measurement value in accordance with a length of the boom;

a derricking angle sensor configured to output a fourth measurement value in accordance with a derricking angle of the boom; and

an input device configured to receive an input of a relative height indicating a difference between a crane installation surface and the surveillance-target surface, wherein

the suspended-load height deciding processing is a processing of calculating the suspended-load height based on the relative height, the first measurement value, the third measurement value, and the fourth measurement value.
The crane apparatus according to claim 1, wherein the suspended-load height deciding processing includes a processing of deciding the suspended-load height based on a size of a specific object captured in the surveillance image and a threshold size or a calculation formula prestored in a memory.
The crane apparatus according to claim 1, wherein
an angle of view of the surveillance camera is constant,

the controller is configured to further execute a camera height deciding processing of deciding a camera height that is a distance from the surveillance-target surface to the surveillance camera, and

the determination area setting processing is a processing of setting the determination area further based on the camera height.
The crane apparatus according to claim 1, wherein
the controller comprises:
a computer; and

a memory configured to store a control program that causes the computer to execute the suspended-load height deciding processing, the determination area setting processing, the result obtaining processing, and the safety processing, and a human determining program that causes the computer to execute a human determining processing of determining whether a human is captured and a processing of outputting a determination result, wherein

the determination area setting processing includes a processing of generating determination image data based on the suspended-load height and the surveillance image data, and

the result obtaining processing includes a processing of passing the determination image data to the human determining program, and a processing of receiving the determination result from the human determining program.
The crane apparatus according to claim 1, wherein
the controller is configured to further execute a camera height deciding processing of deciding a camera height that is a distance from the surveillance-target surface to the surveillance camera, and

the determination area setting processing includes an amplitude deciding processing of deciding an amplitude of a swing of the suspended load based on the camera height and the surveillance image data, and is a processing of setting the determination area based on the amplitude.
A crane apparatus comprising:
a slewing base;

a boom mounted on the slewing base and capable of standing, lying, extending, and retracting;

a winch provided at a base end portion side of the boom and capable of paying out and winding up a wire rope;

a suspended-load hook connected to the wire rope, the wire rope paid out from the winch and hung around a tip end portion of the boom;

a surveillance camera installed at the tip end portion of the boom and configured to capture an image downward to output surveillance image data;

an operating device configured to receive a slewing operation of the slewing base and a derricking operation and an extending/retracting operation of the boom; and

a controller to which the surveillance image data is input, wherein

the controller is configured to execute:
a hook height deciding processing of deciding a hook height that is a distance from a surveillance-target surface to the suspended-load hook;

a hook height determining processing of determining whether the hook height is less than a threshold height prestored in a memory;

a trajectory estimating processing of estimating a movement trajectory of the suspended-load hook until a predetermined time passes based on a movement direction and a movement speed indicated respectively by the slewing operation, the derricking operation, and the extending/retracting operation, based on a fact that the hook height is less than the threshold height;

a determination area setting processing of setting a part of an area of an image indicated by the surveillance image data as a determination area for determining whether a human is captured, based on the surveillance image data and the movement trajectory;

a result obtaining processing of obtaining a determination result whether a human is captured in the determination area; and

a predetermined safety processing based on a fact that the determination result indicating that a human is captured in the determination area is obtained.
The crane apparatus according to claim 9, further comprising a suspended-load load sensor configured to output a measurement value in accordance with a load applied to the wire rope by a suspended load, and
the controller is configured to execute the hook height deciding processing, the trajectory estimating processing, the determination area setting processing, the result obtaining processing, and the safety processing, based on a fact that the load indicated by the measurement value is zero.