JP2017145564A - Safety apparatus of mobile machine - Google Patents

Abstract

PROBLEM TO BE SOLVED: To restrain working efficiency from being decreased because an alert is sent to a person who is not exposed to a risk of interference, and concurrently prevent the interference between a mobile machine and the person around it.SOLUTION: An interference determination part 271 determines a risk of interference between a mobile machine 1 and a person on the basis of the position of the person, which is detected by a position detection part 5. A notification control part 272 controls an ultrasonic loud speaker 6 so that a warning sound can be output to the detected position of the person, when the presence of the risk of the interference is determined by the interference determination part 271.SELECTED DRAWING: Figure 2

Description

  The present invention relates to a safety device for a movable machine that prevents a movable machine such as a construction machine, an automobile, and a robot from interfering with a surrounding person.

  In recent years, in the field of movable machines such as construction machines, automobiles, and robots, research on techniques for preventing interference with surrounding people has been actively conducted in response to the need for automated driving. For example, in the construction machine, the interference with the surrounding person is that the operator turns the upper swing body without knowing it even though the operator has invaded behind the blind spot of the construction machine, It occurs when the lower traveling body is moved backward.

  In order to prevent this, as shown in FIG. 9, in Patent Document 1, a worker (6) working around a construction machine (1) is attached with an infrared light emitter (7) and the construction machine (1 The infrared ray receiver (5) is attached to the upper rotating body (2) of (2). Then, when the infrared ray receiver (5) receives the infrared ray output from the infrared ray emitter (7), it is detected that the worker (6) has entered the warning area of the construction machine (1). (6) discloses a technique for issuing an alarm.

  As shown in FIG. 10, in Patent Document 2, the power shovel body (3) is provided with a proximity sensor (51, 52) and an air blowing nozzle (61, 62), and the power shovel body (3) turns. In this case, a technique is disclosed in which air is blown out from the air blowing nozzles (61, 62) according to the response of the proximity sensor (51, 52), and the operator is informed of the approach of the power shovel body (3) by the air. ing.

JP 2002-212981 A JP 2001-171983 A

  However, in Patent Document 1, since it is necessary to attach the infrared light emitter (7) to the worker (6), there is a problem that a burden is imposed on the worker. Moreover, in patent document 1, it is necessary to manage the battery running out of an infrared rays light emitter (7), and there also exists a problem that a maintenance takes time.

  In addition, when the construction machine is idling or excavating, there is no operation such as backward running or turning 180 degrees, so even if there are workers behind the construction machine, Very unlikely to interfere with construction machinery. However, in Patent Document 1, even in such a case, an alarm is issued each time the infrared receiver (5) receives infrared light emitted from the infrared emitter (7). There is a problem of significantly lowering.

  Further, Patent Document 2 does not generate a burden on the worker as in Patent Document 1, and does not require maintenance of an apparatus worn by the worker. However, if the output of air is strong, problems such as blown away workers and loss of balance of workers occur. On the other hand, if the output of air is suppressed, there is a problem that if the power shovel main body (3) does not come close to the worker, the worker cannot feel the air.

  Further, if the wind is strong on the day, it becomes difficult for the operator to distinguish between the air blown from the air blowing nozzles (61, 62) and the normal wind, and the reliability of the warning is lowered. There is.

  Furthermore, as shown in FIG. 10, the air outlet is oriented perpendicularly to the side surface of the rear portion of the power shovel body (3). If the excavator body (3) does not turn, the blowing nozzle (61, 62) cannot apply air to the worker. For this reason, the blow-off nozzles (61, 62) have a problem that the air can be applied to the worker for the first time just before the interference, and there is a high risk of interference.

  SUMMARY OF THE INVENTION An object of the present invention is to provide a movable machine capable of preventing a decrease in work efficiency due to a warning being given to a person who does not have the risk of interference, and at the same time preventing interference between a nearby person and the movable machine. Provide safety devices.

A safety device for a movable machine according to one aspect of the present invention is a safety device for a movable machine that prevents interference between the movable machine and a person,
A position detector for detecting the position of a person existing around the movable machine;
An interference determination unit that determines a risk of interference between the movable machine and the person based on the position of the person detected by the position detection unit;
An ultrasonic speaker provided in the movable machine;
A notification control unit that controls the directivity of the ultrasonic speaker so that an alarm sound is output to the detected position of the person when the interference determination unit determines that there is a risk of the interference; Prepare.

  According to this aspect, since the alarm sound is output using the ultrasonic speaker, the sound wave having strong directivity can be generated, and the alarm can be issued only to a person having a high risk of interference. . As a result, it is possible to prevent bothersomeness of alarming a person who has a low risk of interference and a decrease in work efficiency due to the alarm being given to this person. On the other hand, since a warning is issued to a person who has a high risk of interference, the corresponding person can be surely recognized of the risk of interference, and interference between the movable machine and the corresponding person can be prevented in advance. . Moreover, compared with the technique which alerts using air as shown to patent document 2, there is also no danger that the person who becomes a warning object will lose a balance and will be blown away by air.

In the above aspect, further comprising an actuator for physically changing the direction of the ultrasonic speaker,
The notification control unit may direct the directivity of the ultrasonic speaker toward the detected person by controlling the actuator.

  According to this aspect, since the actuator for physically changing the direction of the ultrasonic speaker is provided, the alarm sound can be output in a desired direction without arranging many ultrasonic speakers in the movable machine. And the equipment configuration can be simplified.

In the above aspect, the ultrasonic speaker is constituted by an ultrasonic array in which a plurality of ultrasonic elements are arranged on a plane,
The notification control unit may direct the directivity of the ultrasonic speaker toward the detected person by controlling phases of ultrasonic waves output from the plurality of ultrasonic elements.

  According to this aspect, since the directivity of the warning sound is adjusted by controlling the phase of the ultrasonic wave output from the ultrasonic element, even without arranging many ultrasonic speakers in the movable machine, An alarm sound can be output in a desired direction, and the device configuration can be simplified.

In the above aspect, further comprising an operation unit for operating the movable machine,
The interference determination unit detects that the movable machine operates toward the detected position of the person based on an operation amount of the operation unit, and the position of the person is relative to the movable machine. If it is within a predetermined distance range, it may be determined that there is a risk of the interference.

  According to this aspect, it is determined that there is a risk of interference when it is detected that the movable machine operates toward the detected position of the person and the person is within a predetermined distance range with respect to the movable machine. The person is warned. Therefore, even when a person is close to the movable machine, it is possible to prevent the person from being warned if the movable machine is operating in a direction away from the person. As a result, it is possible to suppress a decrease in work efficiency due to a warning given to a person having a low risk of interference.

  According to the present invention, since an alarm can be issued only to a person having a high risk of interference, a reduction in work efficiency due to an alarm being given to a person having a low risk of interference is suppressed, and at the same time It can be prevented in advance.

It is a figure which shows an example of the movable machine to which the safety device which concerns on embodiment of this invention was applied. It is a block diagram which shows the structure of the movable machine shown in FIG. It is a flowchart which shows the process of the safety device of the movable machine which concerns on embodiment of this invention. It is the figure which showed a mode that a position detection part detected a person. It is a figure which shows an example of a movable machine at the time of using the method 1. FIG. It is a block diagram which shows the structure of the movable machine at the time of employ | adopting the method 1. FIG. 12 is an explanatory diagram of phase control in Method 2. FIG. It is a figure explaining the process which determines the danger of the interference of a person and a movable machine. It is a figure which shows a prior art. It is a figure which shows a prior art.

[Basic configuration]
FIG. 1 is a diagram illustrating an example of a movable machine 1 to which a safety device according to an embodiment of the present invention is applied. Here, a construction machine is employed as the movable machine 1, but this is an example. In addition to the construction machine, a moving machine such as a human-type robot and a welding robot having a movable part that may interfere with a person or a car may be adopted as the movable machine 1. In the example of FIG. 1, a hydraulic excavator is employed as the construction machine, but this is an example, and a hydraulic crane may be employed.

  A movable machine 1 shown in FIG. 1 includes a crawler-type lower traveling body 2, an upper revolving body 3 that is turnable on the lower traveling body 2, and a work device 4 that is attached to the upper revolving body 3. ing. In the present specification, the forward direction of the lower traveling body 2 is referred to as the front, the backward direction of the lower traveling body 2 is referred to as the rear, and the direction in which the front and rear are collectively referred to as the front-rear direction. Further, the left direction when the lower traveling body 2 is viewed from the rear forward is referred to as the left direction, and the right direction when the lower traveling body 2 is viewed from the rear forward is referred to as right, left and right. This is called the left-right direction. The upper direction of the movable machine 1 is referred to as the upper direction, the lower direction of the movable machine 1 is referred to as the lower direction, and the upper and lower directions are collectively referred to as the up-down direction. In addition, in FIG. 1, the movable machine 1 when it looks downward from upper direction is shown.

  The work device 4 includes a boom 41 attached to the upper swing body 3 so as to be able to move up and down, an arm 42 attached so as to be swingable with respect to a distal end portion of the boom 41, and a swing with respect to the distal end portion of the arm 42. And an attachment 43 movably attached thereto. The boom 41, the arm 42, and the attachment 43 are raised and lowered by corresponding hydraulic cylinders (not shown).

  In general, the upper swing body 3 includes a front side surface 3F provided on the front side, a right side surface 3R provided on the right side, and a rear side surface 3B provided on the rear side when the turning angle is 0 degree. , A rectangular parallelepiped shape surrounded by four side surfaces with the left side surface 3L provided on the left side.

  When the movable machine 1 is viewed from above, the position detection unit 5 is provided at each of the four vertices of the upper swing body 3. That is, the upper swing body 3 includes four position detection units 5. The position detection unit 5 is configured by, for example, an infrared sensor that detects a person around the movable machine 1 by irradiating infrared rays. The arrangement of the position detection unit 5 shown in FIG. 1 is merely an example, and for example, five or more position detection units 5 may be arranged, or three or less position detection units 5 may be arranged. . Further, from the viewpoint of detecting a person in the blind spot of the operator, the position detector 5 on the front side surface 3F may be omitted.

  When the movable machine 1 is viewed from above, the ultrasonic speakers 6 are provided one by one at substantially the center positions of the front side surface 3F, the right side surface 3R, the rear side surface 3B, and the left side surface 3L. That is, the upper swing body 3 includes four ultrasonic speakers 6. In addition, arrangement | positioning of the ultrasonic speaker 6 shown in FIG. 1 is only an example, for example, five or more ultrasonic speakers 6 may be arrange | positioned and three or less ultrasonic speakers 6 may be arrange | positioned. . Further, from the viewpoint that it is sufficient to warn a person in the blind spot of the operator, the ultrasonic speaker 6 on the front side surface 3F may be omitted.

  The ultrasonic speaker 6 is constituted by an ultrasonic array in which ultrasonic elements 61 constituted by transducers are arranged in an array on a plane.

  FIG. 2 is a block diagram showing a configuration of the movable machine 1 shown in FIG. The movable machine 1 includes an engine 21, a hydraulic pump 22, a travel motor 23, a travel control valve 24, a swing motor 25, a swing control valve 26, a controller 27, in addition to the position detector 5 and the ultrasonic speaker 6 shown in FIG. An operation unit 28 is provided. In FIG. 2, the flow of hydraulic oil is indicated by a thick line, and the flow of control signals is indicated by a thin line. Moreover, in FIG. 1, components other than the engine 21 and the hydraulic pump 22 are components of the safety device of the movable machine 1 according to the embodiment of the present invention.

  The engine 21 is composed of, for example, a diesel engine. The hydraulic pump 22 is connected to the drive shaft 21X of the engine 21, is driven by the power of the engine 21, and discharges hydraulic oil.

  The traveling motor 23 is configured by a hydraulic motor that is operated by hydraulic oil supplied from the hydraulic pump 22, and causes the lower traveling body 2 to travel. Here, under the control of the travel control valve 24, the travel motor 23 switches between forward and reverse travel of the lower traveling body 2, adjusts the travel speed, and automatically stops the travel operation.

  The travel control valve 24 is an electromagnetic control valve provided on a hydraulic path connecting the hydraulic pump 22 and the travel motor 23, and the amount of hydraulic oil supplied from the hydraulic pump 22 to the travel motor 23 under the control of the controller 27. Is adjusted to control the traveling operation of the traveling motor 23.

  The turning motor 25 is composed of a hydraulic motor that is operated by hydraulic oil supplied from the hydraulic pump 22, and turns the upper turning body 3. Here, under the control of the turning control valve 26, the turning motor 25 switches the left turning and the right turning of the upper turning body 3, adjusts the turning speed, and automatically stops the turning operation. .

  The swing control valve 26 is an electromagnetic control valve provided on a hydraulic path connecting the hydraulic pump 22 and the swing motor 25, and the amount of hydraulic oil supplied from the hydraulic pump 22 to the swing motor 25 under the control of the controller 27. Is adjusted to control the turning operation of the turning motor 25.

  The controller 27 is composed of, for example, a microcomputer including a CPU, a ROM, a RAM, and the like, and controls the entire movable machine 1. In the present embodiment, the controller 27 includes an interference determination unit 271, a notification control unit 272, and an interference prevention unit 273. The interference determination unit 271 to the interference prevention unit 273 may be realized, for example, by a CPU executing a program, or may be configured by a dedicated hardware circuit.

  The interference determination unit 271 determines the risk of interference between the movable machine 1 and the person based on the position of the person detected by the position detection unit 5. Here, when the interference determination unit 271 detects that the movable machine 1 operates toward the position of the person detected by the position detection unit 5 based on the operation amount of the operation unit 28, there is a risk of interference. What is necessary is just to determine that there exists. In this case, the interference determination unit 271 determines the operation direction of the movable machine 1 from the operation amount of the operation unit 28, sets the alarm region DX according to the determined operation direction (see FIG. 8), and sets the alarm region If a person exists in DX, it may be determined that there is a risk of interference.

  When the interference determination unit 271 determines that there is a risk of interference, the notification control unit 272 controls the directivity of the ultrasonic speaker 6 so that an alarm sound is output at the detected position of the person. As the alarm sound, for example, a buzzer sound may be employed, or a voice message for notifying a person that the risk of interference is high may be employed.

  The interference prevention unit 273 is movable when the interference determination unit 271 determines that there is a risk of interference, and when it is determined that the person exists in the automatic driving area DX1 (see FIG. 8). In order to avoid interference with the machine 1, the movable machine 1 is automatically operated. Specifically, the interference prevention unit 273 outputs a stop signal to the travel control valve 24, causes the travel control valve 24 to shut off the supply of hydraulic oil to the travel motor 23, and automatically stops the travel motor 23. Alternatively, the interference prevention unit 273 outputs a stop signal to the turning control valve 26, causes the turning control valve 26 to cut off the supply of hydraulic oil to the turning motor 25, and automatically stops the turning motor 25.

  In addition, the interference prevention unit 273 controls the travel control valve 24 so that the travel motor 23 operates at a travel speed and a travel direction corresponding to the operation amount of the travel operation lever 281. Further, the interference prevention unit 273 controls the turning control valve 26 so that the turning motor 25 operates at a turning speed and a turning direction corresponding to the operation amount of the turning operation lever 282.

  The position detection unit 5 acquires, for example, a laser range finder that acquires distance image data around the movable machine 1 by measuring a time period from irradiation of infrared rays to reception of reflected light, and a laser range finder. A person detection sensor includes a processor that extracts a person from the obtained distance image data and performs a process of tracking the extracted person to perform person recognition. Here, for example, the processor may cluster the distance image data, and determine the pixel group as a person when the shape of the clustered pixel group satisfies a predetermined condition. Thereafter, the processor tracks the pixel group indicating the person from the distance image data sequentially acquired by the laser range finder, and sequentially outputs the distance data of the pixel group to the controller 27. Thereby, the controller 27 can acquire distance data of a person located around the movable machine 1.

  Here, a person detection sensor using a laser range finder is adopted as the position detection unit 5, but this is an example, and a person detection sensor that detects a person using an around view monitor widely used in automobiles or the like is used. It may be adopted. The position of the person around the movable machine 1 can be recognized by these existing technologies.

  The ultrasonic speaker 6 is composed of, for example, a parametric speaker that can give a sharp directivity to the audible sound output by using ultrasonic waves.

  Two types of parametric speakers are known. The first method uses a frequency shift between two ultrasonic waves, and transmits ultrasonic waves having a constant frequency and AM-modulated ultrasonic waves to reproduce audible sound in the space where the ultrasonic waves intersect. It is a method to do. Another method is a method of transmitting ultrasonic waves obtained by AM-modulating audible sound from a plurality of transducers arranged in a plane. In the present embodiment, any method may be adopted for the ultrasonic speaker 6.

  Thereby, an audible sound can be selectively output to a person in a specific narrow range. Therefore, by employing an alarm sound as an audible sound, an alarm sound can be selectively output to a person who is exposed to the risk of interference. As a result, it is possible to prevent the troublesomeness that an alarm sound is output to an irrelevant person and the reduction in work efficiency due to the output of an alarm sound to that person.

  The operation unit 28 includes a traveling operation lever 281 to which an operation from an operator for traveling the lower traveling body 2 is input, and a turning operation lever 282 to which an operation from an operator for rotating the upper revolving body 3 is input. Is provided.

  For example, the traveling operation lever 281 is configured to be tiltable in the front-rear direction. For example, when the lower traveling body 2 is moved forward, the traveling operation lever 281 is tilted forward, and when the lower traveling body 2 is moved backward, the traveling operation lever 281 is tilted backward.

  The turning operation lever 282 is configured to be tiltable in the left-right direction, for example. When the upper turning body 3 is turned to the right, for example, it is tilted to the right and the upper turning body 3 is turned to the left. Tilt in the direction.

  Note that, for both operation levers, a certain angle range including the case where the tilt amount is 0 is set as the neutral range. Further, both the operation levers include, for example, a potentiometer, and output an operation amount whose value increases as the tilt angle increases to the controller 27. Specifically, when the travel operation lever 281 is tilted forward, the operation amount whose value increases in the positive direction as the tilt angle increases is output to the controller 27. When the travel operation lever 281 is tilted backward, the travel operation lever 281 is tilted. As the angle increases, an operation amount whose value increases in the negative direction is output to the controller 27.

  When the turning operation lever 282 is tilted to the right, it outputs an operation amount whose value increases in the positive direction to the controller 27 as the tilt angle increases, and when it is tilted to the left, the tilt angle increases. As the operation proceeds, an operation amount whose value increases in the negative direction is output to the controller 27.

[flowchart]
FIG. 3 is a flowchart showing processing of the safety device of the movable machine 1 according to the embodiment of the present invention. The flowchart of FIG. 4 starts when the movable machine 1 drives the engine 21 and is ready for operation.

  In S <b> 1, the position detection unit 5 performs a process of detecting a person existing around the movable machine 1.

  FIG. 4 is a diagram showing how the position detection unit 5 detects the persons PA and PB. As shown in FIG. 5, the position detectors 5 are arranged at the four corners of the upper swing body 3 in a top view. As described above, the position detection unit 5 employs an infrared laser range finder. In a top view, the angle of view of one position detection unit 5 is, for example, about 270 degrees. Therefore, by arranging the position detectors 5 at the four corners of the upper swing body 3, the detectable range D41 that can be detected by a person can be set in all directions (range of 360 degrees) of the movable machine 1.

  In the example of FIG. 5, the detectable range D41 is set to a substantially circular region having a constant radius from the center of the movable machine 1 when viewed from above. In the example of FIG. 5, since there are two persons PA and PB in the detectable range D41, the position detection unit 5 detects the distance data of the pixel group indicating each of the persons PA and PB. To do.

  Here, the distance data detected by the position detection unit 5 will be supplemented a little. Each of the position detection units 5 has a local coordinate space, and first detects distance data of a person in the local coordinate space. Then, the position detection unit 5 may perform an operation for converting the local coordinate space into the coordinate space of the movable machine 1 on the detected distance data, and output it to the controller 27. The coordinate space of the movable machine 1 is, for example, three coordinates in the front-rear direction, the left-right direction, and the up-down direction with a predetermined position of the movable machine 1 (for example, a position on the rotation axis of the upper swing body 3) as an origin. It is a three-dimensional coordinate space that represents the coordinates of each position by components. Therefore, the distance data output from the position detector 5 is represented by these three coordinate components. However, this is an example, and the coordinate space of the movable machine 1 may be represented by a polar coordinate space.

  In S2, the interference determination unit 271 determines whether or not the operation unit 28 is operated. Here, the interference determination unit 271 determines that the operation unit 28 is operated when the absolute value of the operation amount of the travel operation lever 281 or the turning operation lever 282 indicates a value equal to or greater than the neutral range. If it is determined in S2 that the operation unit 28 is operated (YES in S2), the process proceeds to S3. If it is determined in S2 that the operation unit 28 is not operated (NO in S2), the process Is returned to S1.

  In S <b> 3, the interference determination unit 271 determines the risk of interference between the person detected in S <b> 1 and the movable machine 1. FIG. 8 is a diagram for explaining processing for determining the risk of interference between a person and the movable machine 1.

  Here, for example, when an operation for moving the lower traveling body 2 backward is input, the interference determination unit 271 sets an alarm area DB behind the lower traveling body 2 so that a person is located in the alarm area DB. If yes, it is determined YES in S3. In addition, for example, when an operation for moving the lower traveling body 2 is input, the interference determination unit 271 sets an alarm area DF in front of the lower traveling body 2, and if the person is located in the alarm area DF , S3 determines YES.

  Further, for example, when an operation for turning the upper swing body 3 to the right is input, the interference determination unit 271 sets an alarm area DR on the right side of the upper swing body 3 and the person is located in the alarm area DR. If so, YES is determined in S3. Further, for example, when an operation for turning the upper swing body 3 to the left is input, the interference determination unit 271 sets an alarm area DL on the left side of the upper swing body 3 and the person is located in the alarm area DL. If so, YES is determined in S3.

  As described above, the interference determination unit 271 sets the alarm area DX in an area where there is a high possibility of interference according to the operation direction of the movable machine 1, and only when a person is located in the alarm area DX, Judged as dangerous. Thereby, it is determined that there is a risk of interference only when the moving direction of the movable machine 1 is toward the person. As a result, when the person is located in the vicinity of the movable machine 1 but the moving direction of the movable machine 1 is away from the person, it is determined that there is no risk of interference. Reduction can be suppressed.

  Here, the warning area DF is a rectangular area having a width in the left-right direction that is about the same as the width in the left-right direction of the lower traveling body 2 in a top view. In the warning area DF, a square-shaped automatic operation area DF1 is provided on the lower traveling body 2 side.

  The alarm area DB is a quadrangular area whose width in the left-right direction is about the same as the width in the left-right direction of the lower traveling body 2 when viewed from above. The width in the front-rear direction of the alarm areas DF and DB is set to a length that may cause the person and the upper swing body 3 to interfere with each other, for example. In the alarm area DB, a rectangular automatic operation area DB1 is provided on the lower traveling body 2 side.

  The alarm area DR is a fan-shaped area provided on the right side of the work device 4 with the tip of the work device 4 as a starting point when viewed from above. The arc of the alarm region DR is defined by, for example, a locus drawn by the tip of the work device 4 when the upper swing body 3 turns right. Within the alarm region DR, a fan-shaped automatic operation region DR1 is provided on the work device 4 side.

  The alarm area DL is a fan-shaped area provided on the left side of the work device 4 with the front end of the work device 4 as a starting point in a top view. The arc of the alarm area DL is defined by, for example, a locus drawn by the tip of the work device 4 when the upper swing body 3 turns left. In the alarm area DL, a fan-shaped automatic operation area DL1 is provided on the working device 4 side.

  In the example of FIG. 8, the central angles of the alarm areas DR and DL are each set to about 90 degrees. However, this is an example, and the angle may cause the person and the work device 4 to interfere with each other. Any angle may be adopted. Hereinafter, when the alarm areas DF, DB, DR, and DL are not distinguished, they are described as the alarm area DX. Moreover, when not distinguishing automatic operation area | region DF1, DB1, DR1, DL1, it describes as automatic operation area | region DX1.

  Hereinafter, the person who is determined to have the risk of interference in S3 is described as the “target person” to be alarmed. In the example of FIG. 8, since the person PA exists in the detectable range D41, it is detected by the position detection unit 5, but does not become a target person because it is not located in the alarm area DX.

  In addition, since the person PB is located in the warning area DB, the person PB is a target person if an operation of moving backward by the traveling operation lever 281 is input. On the other hand, if an operation for moving backward by the travel operation lever 281 is not input, the operation direction of the movable machine 1 is not directed to the position of the person PB, and therefore the person PB is not a target person.

  In the example of FIG. 8, the range in the vertical direction of the alarm area DX is not shown, but when determining whether a person exists in the alarm area DX using only the coordinate components in the horizontal direction and the front-back direction, The alarm area DX may not have a specified range in the vertical direction. On the other hand, when determining whether or not a person exists in the alarm area DX using the vertical coordinate component, the vertical range of the alarm area DX is, for example, a height slightly higher than the height of the person from the ground. A range up to (2 m, 2.5 m, etc.) may be adopted.

  In S4, the notification control unit 272 controls the directivity of the ultrasonic speaker 6 so that an alarm sound is output at the position of the target person. Details of this control will be described later.

  In S5, the interference determination unit 271 determines whether or not the target person is located in the automatic driving area DX1. In the example of FIG. 8, the person PB is located in the alarm area DB but not in the automatic operation area DB1, so that NO is determined in S5, and the process returns to S1. On the other hand, if the target person is located in the automatic driving area DX1, it is determined YES in S5, and the process proceeds to S6.

  In S <b> 6, the interference prevention unit 273 automatically stops the operation of the movable machine 1 regardless of the operation of the operation unit 28 because the target person is located in the automatic driving area DX <b> 1 and the risk of interference is high.

  Here, the interference prevention unit 273 outputs a stop signal to the traveling control valve 24 and automatically stops the traveling motor 23 if the target person is located in either of the automatic driving regions DF1 and DB1. Moreover, if the target person is located in either of the automatic driving regions DR1 and DL1, the interference prevention unit 273 outputs a stop signal to the turning control valve 26 to automatically stop the turning motor 25. When the process of S6 ends, the process returns to S1, and the processes after S1 are repeated. The process shown in FIG. 4 is continued as long as the engine 21 is operable.

  In the example of FIG. 8, the warning area DF is provided. However, since the operator is highly likely to notice a person in front of the movable machine 1, the warning area DF may be omitted.

[Control of ultrasonic speaker 6]
In the present embodiment, the following two methods are adopted as control of the ultrasonic speaker 6.

[Method 1]
Method 1 uses the actuator 7 to change the direction of the ultrasonic speaker 6. FIG. 5 is a diagram illustrating an example of the movable machine 1 when the method 1 is used. 5 is different from FIG. 1 in that an actuator 7 for changing the direction of the ultrasonic speaker 6 is further provided on the upper swing body 3. In the example of FIG. 5, it is assumed that the person PB is the target person.

  As shown in FIG. 3, the ultrasonic speaker 6 has a plurality of ultrasonic elements 61 arranged in an array. Thereby, the directivity to the direction orthogonal to the plane in which the ultrasonic element 61 is arrange | positioned is improved by outputting the ultrasonic wave which carried out AM modulation of the audible sound from each ultrasonic element 61. FIG.

  In the example of FIG. 5, the ultrasonic speaker 6 attached to the rear side surface 3B is shown. Here, in the ultrasonic speaker 6, the direction orthogonal to the speaker surface 62, which is a plane on which the ultrasonic element 61 (see FIG. 1) is arranged, is set as the directivity direction D51. The same applies to the ultrasonic speakers 6 attached to the front side surface 3F, the right side surface 3R, and the left side surface 3L.

  Here, in order to simplify the explanation, it is assumed that the actuator 7 is composed of, for example, a single-axis actuator that can change the directivity direction D51 on a horizontal plane. The horizontal plane refers to a plane represented by two axes, a left-right direction and a front-rear direction. In addition, the ultrasonic speaker 6 is approximately the height (for example, 160 to 180 cm) of the persons PA and PB who are workers on the front side surface 3F, the rear side surface 3B, the right side surface 3R, and the left side surface 3L of the upper swing body 3. It is assumed that it is installed in.

  Therefore, the notification control unit 272 can output an alarm sound toward the person PB by controlling the actuator 7 so that the directivity direction D51 faces the position of the person PB in the top view. The position of the person PB in the top view indicates the coordinate components in the left-right direction and the front-rear direction among the three coordinate components constituting the distance data of the person PB. Further, as the position of the person PB, a representative point of the person PB output from the position detection unit 5 may be adopted. As the representative point, for example, the center point of the whole person PB may be employed, the center point of the body of the person PB may be employed, or the center point of the face of the person PB may be employed.

  In addition to the horizontal plane, the actuator 7 may be a biaxial actuator that can change the directivity direction D51 on a vertical plane orthogonal to the horizontal plane. In this case, the notification control unit 272 considers three coordinate components obtained by adding the vertical and vertical coordinate components to the horizontal and front and rear coordinate components at the representative point of the person PB. The actuator 7 may be controlled so that the directivity direction D51 is directed.

  In the example of FIG. 5, since the ultrasonic speaker 6 installed on the rear side surface 3B is closest to the person PB, an alarm sound is output only from the ultrasonic speaker 6, and the ultrasonic speaker 6 is directional. The direction D51 was to be changed. This is an example, and the ultrasonic speaker 6 that is the output target of the alarm sound and the change target of the directivity direction D51 is the ultrasonic speaker that is closest to the target person among the four ultrasonic speakers 6. 6 may be used.

  For example, in FIG. 5, if the person PA is the target person, the ultrasonic speaker 6 installed on the left side surface 3L closest to the person PA is the output target of the alarm sound and the change target of the directivity direction D51. It should be done. This is the same for Method 2 described later.

  In addition, a plurality of target persons may be detected around the movable machine 1. In this case, the ultrasonic speaker 6 that is closest to each target person only needs to be an alarm sound output target and a target for changing the directivity direction D51. This is the same for Method 2 described later.

  There may be one ultrasonic speaker 6 closest to each of a plurality of target persons. In this case, the notification control unit 272 may control the actuator 7 so that an alarm sound is output toward one target person with high risk among a plurality of target persons. For example, a person closest to the movable machine 1 may be employed as one target person with high risk. In addition, when there is a target person on the front, rear, left, and right of the movable machine 1, the notification control unit 272 may output an alarm sound from all the ultrasonic speakers 6. In this case, the notification control unit 272 may output an alarm sound in all directions by scanning the directivity direction D51. This can also be applied to Method 2 described later.

  FIG. 6 is a block diagram illustrating a configuration of the movable machine 1 when the method 1 is employed. 6 differs from FIG. 2 in that an actuator 7 is newly provided. As the actuator 7, for example, a hydraulic motor may be employed, or an electric motor may be employed. In the present embodiment, since four ultrasonic speakers 6 are provided, four actuators 7 corresponding to each are provided.

  In Method 1, the notification control unit 272 outputs a signal obtained by AM-modulating an audible sound signal indicating an alarm sound from the ultrasonic speaker 6 so that the directivity direction D51 is directed toward the target person. The actuator 7 may be controlled.

  According to the technique 1, since the actuator 7 is used, for example, an alarm sound can be output in the direction of the target person without disposing the ultrasonic speaker 6 over the entire side surface of the upper swing body 3, Can be simplified.

[Method 2]
Method 2 is a method of outputting an alarm sound in the direction of the target person by controlling the phases of the ultrasonic waves output from the plurality of ultrasonic elements 61. In Method 2, since the actuator 7 is not used, the block configuration is the same as in FIG.

  FIG. 7 is an explanatory diagram of phase control in Method 2. In FIG. 7, the ultrasonic element 61 from the top view is shown. As shown in FIG. 1, the ultrasonic speaker 6 is configured by an ultrasonic array in which a plurality of ultrasonic elements 61 are arranged in an array. Therefore, the directivity direction D51 of the ultrasonic speaker 6 can be directed to a desired direction by controlling the phase of the ultrasonic wave output from each ultrasonic element 61.

  In FIG. 7, in the left diagram, ultrasonic waves are output from the ultrasonic elements 61 with the same phase. In this case, since the phases of the ultrasonic components W1 to W3 in the direction A1 of 90 degrees with respect to the speaker surface 62 are aligned, the ultrasonic components W1 to W3 in the direction A1 strengthen each other. As a result, an ultrasonic wave having the maximum intensity in the direction A1 is output from the ultrasonic speaker 6, and the directivity direction D51 faces the direction A1. In the example of FIG. 7, since the ultrasonic element 61 is shown from the top view, the directivity direction D51 is parallel to the horizontal plane.

  On the other hand, in the right diagram of FIG. 7, there are two rows with respect to the first row of ultrasonic elements 61 such that the phases of the ultrasonic components W1 to W3 are aligned in the direction A2 inclined by the angle θx with respect to the direction A1. The phase of the ultrasonic element 61 of the eye and the ultrasonic element 61 of the third row are shifted. As a result, the ultrasonic components W1 to W3 in the direction A2 strengthen each other, and ultrasonic waves having the maximum intensity in the direction A2 are output from the ultrasonic speaker 6, and the directivity direction D51 faces the direction A2. In the example of FIG. 7, since the ultrasonic element 61 is shown from the top view, the directivity direction D51 is parallel to the horizontal plane.

  Here, when the phase shift of the ultrasonic element 61 in the n-th row (n is an integer of 2 or more) from the top with respect to the ultrasonic element 61 in the first row is α (n) (rad), α ( n) is represented by Formula (1).

α (n) = 2π (n−1) · d · sin θx / λ (1)
However, d represents the distance between the ultrasonic elements 61 in meters, and λ represents the wavelength of the ultrasonic waves emitted from the ultrasonic elements 61 in meters.

  Therefore, in Method 2, the notification control unit 272 adjusts the directivity direction D51 of the ultrasonic wave in the entire ultrasonic speaker 6 by controlling the phase shift of each ultrasonic element 61 based on Expression (1). To do.

  Although FIG. 7 shows an example in which the directivity direction D51 is changed on the horizontal plane, it can be changed on the vertical plane. The phase control in this case can be easily estimated by assuming that the ultrasonic elements 61 are arranged in the vertical direction in FIG.

  Specifically, the angle θx indicating the direction on the horizontal plane in the expression (1) is replaced with the angle θy indicating the direction on the vertical plane. Then, the notification control unit 272 sets the phase shift of the ultrasonic elements 61 in the second and subsequent rows with respect to the phase of the ultrasonic elements 61 in the first row as follows.

  That is, the notification control unit 272 sets the phase shift α (2) for the ultrasonic element 61 in the second row as α (2) = 2π · 1 · d · sin θy / λ, For the acoustic wave element 61, the phase shift α (3) is set as α (3) = 2π · 2 · d · sin θy / λ,..., For the ultrasonic element 61 in the nth column, the phase shift α (N) is set to α (n) = 2π (n−1) · d · sin θy / λ. As a result, the directivity direction D51 can be directed to a desired direction on the vertical plane.

  Based on this, the directivity direction D51 can be directed in the direction obtained by vector addition of the direction on the horizontal plane (angle θx) and the direction on the vertical plane (angle θy).

  In this case, the notification control unit 272 first sets a phase shift α (j) with respect to the ultrasonic element 61 in the first row and the first column to α (j) = 2π ( j-1) · d · sin θx / λ. Then, the notification control unit 272 sets the phase shift α (i) of the ultrasonic element 61 in the i-th row and j-th column with respect to the ultrasonic element 61 in the first row and j-th column, α (i) = 2π (i−1). ) · D · sin θy / λ.

  As a result, the directivity direction D51 can be directed in the direction in which the angle θx and the angle θy are vector-added.

  If the technique 2 is used, an alarm sound can be output in the direction of the target person by controlling the phase, so there is no need to arrange the ultrasonic speaker 6 on the entire surface of the movable machine 1 and the configuration of the safety device is simplified. Can be In addition, since it is not necessary to physically change the attitude of the ultrasonic speaker 6, the reliability of the apparatus can be improved.

  As described above, according to the present embodiment, since the alarm sound is output using the ultrasonic speaker 6, it is possible to generate a sound wave having strong directivity and warn only a person having a high risk of interference. Can be issued. As a result, it is possible to prevent bothersomeness of alarming a person who has a low risk of interference and a decrease in work efficiency due to the alarming of that person. On the other hand, since a warning is issued to a person having a high risk of interference, it is possible to make the corresponding person recognize the risk of interference reliably and prevent the interference between the movable machine 1 and the corresponding person in advance. it can.

  When the safety device according to the present embodiment is applied to an automobile, for example, when the automobile moves forward, an alarm area DF is set in front of the automobile, and when the automobile moves backward, an alarm area DB is placed behind the automobile. Should be set. Further, when the vehicle turns left or right, the vehicle trajectory is predicted from the steering operation amount, and an alarm region having a shape along the predicted track may be set in the traveling direction of the vehicle.

D41 Detectable range D51 Directional direction DX, DF, DB, DR, DL Alarm area DX1, DF1, DB1, DR1, DL1 Automatic operation area PA, PB Person 1 Mobile machine 2 Lower traveling body 3 Upper turning body 4 Working device 5 Position detection unit 6 Ultrasonic speaker 7 Actuator 23 Traveling motor 24 Traveling control valve 25 Turning motor 26 Turning control valve 27 Controller 61 Ultrasonic element 271 Interference determining unit 272 Notification control unit 273 Interference prevention unit 28 Operation unit 281 Traveling operation lever 282 Turning Operation lever

Claims (4)

A safety device for a movable machine that prevents interference between the movable machine and a person,
A position detector for detecting the position of a person existing around the movable machine;
An interference determination unit that determines a risk of interference between the movable machine and the person based on the position of the person detected by the position detection unit;
An ultrasonic speaker provided in the movable machine;
A notification control unit that controls the directivity of the ultrasonic speaker so that an alarm sound is output to the detected position of the person when the interference determination unit determines that there is a risk of the interference; Safety device for movable machines. An actuator for physically changing the direction of the ultrasonic speaker;
The safety device for a movable machine according to claim 1, wherein the notification control unit controls the actuator to direct the directivity of the ultrasonic speaker toward the detected person. The ultrasonic speaker is composed of an ultrasonic array in which a plurality of ultrasonic elements are arranged on a plane,
The said alerting | reporting control part directs the directivity of the said ultrasonic speaker to the direction of the said detected person by controlling the phase of the ultrasonic wave output from these ultrasonic elements. Safety device for mobile machines. An operation unit for operating the movable machine;
The interference determination unit detects that the movable machine operates toward the detected position of the person based on an operation amount of the operation unit, and the position of the person is relative to the movable machine. The safety device for a movable machine according to any one of claims 1 to 3, wherein it is determined that there is a risk of the interference when the distance is within a predetermined distance range.

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