阅读说明：本技术 工程机械 (Construction machine ) 是由 齐藤裕保 森木秀一 井村进也 盐饱晃司 于 2020-02-14 设计创作，主要内容包括：本发明具备：姿势检测装置,其设置于前作业机的前部件,检测前部件的姿势信息；外部环境识别装置,其检测主体周围的物体；控制装置,其根据由外部环境识别装置识别出的物体,基于外部环境识别装置的识别范围运算成为死角的范围即死角范围,运算假设存在于死角的移动体在预先确定的时间内能够移动的范围即假设移动范围,并且基于由姿势检测装置检测出的姿势信息来运算前作业机在预定的时间内能够移动的范围即可移动范围,基于移动体的假设移动范围和前作业机的可移动范围,进行预防移动体与前作业机的接触的预防控制。由此,对于物体的死角的移动体也能够充分应对,能够更可靠地切实预防前作业机与移动体的接触。(The present invention is provided with: a posture detection device which is provided on a front member of the front work machine and detects posture information of the front member; an external environment recognition device that detects an object around the subject; and a control device that calculates a blind spot range, which is a range in which a blind spot is formed, based on the recognition range of the external environment recognition device based on the object recognized by the external environment recognition device, calculates a virtual movement range, which is a range in which a moving body in the blind spot can move within a predetermined time, calculates a movement range, which is a range in which the front work machine can move within a predetermined time, based on the posture information detected by the posture detection device, and performs prevention control for preventing the moving body from coming into contact with the front work machine based on the virtual movement range of the moving body and the movable range of the front work machine. This makes it possible to sufficiently cope with a moving body having a blind spot of an object, and to more reliably and reliably prevent the front work implement from coming into contact with the moving body.)

1. A construction machine is provided with:

a main body including a lower traveling structure and an upper revolving structure provided to be able to revolve with respect to the lower traveling structure;

a multi-joint type front working machine attached to the upper slewing body and including a plurality of front members rotatably connected to each other; and

a plurality of actuators that drive a plurality of front members of the front work machine, respectively,

the construction machine is characterized by comprising:

a posture detection device that is provided in a front member of the front work machine and detects posture information of the front member;

an external environment recognition device that detects an object around the subject; and

and a control device that calculates a blind spot range, which is a range to become a blind spot, based on the recognition range of the external environment recognition device, based on the object recognized by the external environment recognition device, calculates a virtual movement range, which is a range in which a moving body present in the blind spot can move within a predetermined time, calculates a range in which the front work machine can move within the predetermined time, that is, a movable range, based on the posture information detected by the posture detection device, and performs prevention control for preventing contact between the moving body and the front work machine, based on the virtual movement range of the moving body and the movable range of the front work machine.

2. The work machine of claim 1,

as the preventive control, the control device controls the actuator of the front work implement so that a movable range of the front work implement does not overlap with an assumed movement range of the movable body.

3. The work machine of claim 1,

when the movable range of the front work implement and the assumed movement range of the movable body are closer than a preset distance, the control device notifies an operator of the fact through an alarm device.

4. The work machine of claim 1,

the construction machine is provided with: a position measuring device that measures a position of the construction machine on a work site; and

a wireless communication device that acquires a position of another construction machine obtained by the other construction machine on the work site and a detection result of an external environment recognition device provided in the other construction machine,

when the dead angle range of the external environment recognition device overlaps with the detection result of the external environment recognition device of the other construction machine, the control device replaces at least a part of the dead angle range with the detection result of the external environment recognition device of the other construction machine.

5. The work machine of claim 1,

the control device determines the type of the object detected by the external environment recognition device, and calculates the blind spot range based on the determined type of the object.

Technical Field

The present invention relates to an engineering machine.

Background

In construction machines such as hydraulic excavators in the civil engineering and construction industry, as a technique for preventing contact between a working machine performing work and a worker or the like, for example, a technique for controlling the working speed of the working machine is disclosed in patent document 1.

Patent document 1 discloses a rotary working machine including: an attachment device that is attached to a traveling body (base) so as to be rotatable; a turning mechanism that turns the attachment; a control device that controls the swing mechanism; and an inlet detection device that detects a position of an inlet entering the work area, wherein the control device controls the turning operation of the attachment based on a first physical quantity related to at least one of an angular velocity of the attachment at a current time point and an inertia moment of the attachment at the current time point, and the position of the inlet detected by the inlet detection device.

Documents of the prior art

Patent document

Patent document 1: japanese laid-open patent publication No. 2012-21290

Disclosure of Invention

Problems to be solved by the invention

However, in the above-described conventional technique, since the possibility that a moving body exists in a blind spot of a detected object is not considered, it is not possible to sufficiently cope with a case where a moving body appears from a blind spot.

The present invention has been made in view of the above circumstances, and an object thereof is to provide a construction machine that can cope with a moving body having a blind spot of an object and can more reliably prevent contact between a front work implement and the moving body.

Means for solving the problems

The present application includes a plurality of methods for solving the above-described problems, and includes, as an example: a main body including a lower traveling structure and an upper revolving structure provided to be able to revolve with respect to the lower traveling structure; a multi-joint type front working machine attached to the upper slewing body and including a plurality of front members rotatably connected to each other; and a plurality of actuators that drive a plurality of front members of the front work machine, respectively, wherein the construction machine includes: a posture detection device provided in a front member of the front work machine and detecting posture information of the front member; an external environment recognition device that detects an object around the subject; and a control device that calculates a blind spot range, which is a range to become a blind spot, based on the recognition range of the external environment recognition device, based on the object recognized by the external environment recognition device, calculates a virtual movement range, which is a range in which a moving body present in the blind spot can move within a predetermined time, calculates a range in which the front work machine can move within the predetermined time, that is, a movable range, based on the posture information detected by the posture detection device, and performs prevention control for preventing contact between the moving body and the front work machine, based on the virtual movement range of the moving body and the movable range of the front work machine.

[ Effect of the invention ]

According to the present invention, even a moving body in a blind spot of an object can be sufficiently coped with, and contact between the front work implement and the moving body can be more reliably and reliably prevented.

Drawings

Fig. 1 is a diagram schematically showing an external appearance of a hydraulic excavator as an example of a construction machine according to a first embodiment.

Fig. 2 is a side view schematically showing an external appearance of the hydraulic excavator.

Fig. 3 is a functional block diagram schematically showing a part of processing functions of the control device mounted in the hydraulic excavator according to the first embodiment.

Fig. 4 is a functional block diagram showing a part of the functions in fig. 3 in detail.

Fig. 5 is a diagram illustrating a dead angle calculation method in the xy plane.

Fig. 6 is a diagram for explaining a dead angle calculation method in the xy plane.

Fig. 7 is a diagram illustrating a dead angle calculation method in the xy plane.

Fig. 8 is a diagram for explaining a dead angle calculation method in the xy plane.

Fig. 9 is a diagram illustrating a case where the bucket of the vehicle is in a blind spot.

Fig. 10 is a diagram illustrating a case where the bucket of the vehicle is in a blind spot.

Fig. 11 is a diagram illustrating a case where the bucket of the vehicle is in a blind spot.

Fig. 12 is a diagram illustrating a calculation method of a velocity limit region and an assumed movement range.

Fig. 13 is a flowchart showing the processing content of the prevention control.

Fig. 14 is a functional block diagram schematically showing a part of processing functions of the control device mounted on the hydraulic excavator in the second embodiment.

Fig. 15 is a diagram for explaining calculation of a blind spot according to the second embodiment.

Fig. 16 is a functional block diagram schematically showing a part of processing functions of a control device mounted on the hydraulic excavator in the third embodiment.

Fig. 17 is a diagram for explaining calculation of a blind spot in the third embodiment.

Fig. 18 is a diagram illustrating an assumed movement range of the mobile object in the third embodiment.

Detailed Description

Hereinafter, embodiments of the present invention will be described with reference to the drawings. In the embodiment of the present invention, a hydraulic excavator provided with a front work implement is described as an example of a construction machine by way of example, but the present invention can also be applied to other construction machines provided with a work implement such as a wheel loader or a crane.

< first embodiment >

A first embodiment of the present invention will be described with reference to fig. 1 to 13.

Fig. 1 is a diagram schematically showing an external appearance of a hydraulic excavator as an example of a construction machine according to the present embodiment. Fig. 2 is a side view schematically showing the external appearance of the hydraulic excavator.

In fig. 1 and 2, the excavator 100 includes: an articulated front work implement 24 configured by connecting a plurality of driven members (boom 8, arm 9, bucket (work tool) 10) that rotate in the vertical direction, respectively; and an upper revolving structure 22 and a lower traveling structure 20 constituting an excavator main body (hereinafter, simply referred to as "main body"), the upper revolving structure 22 being provided so as to be rotatable with respect to the lower traveling structure 20 via a revolving mechanism 21. The turning mechanism 21 includes a turning motor 23 and a turning angle detecting device 27, and the turning motor 23 drives the upper turning body 22 to turn with respect to the lower traveling body 20, and the turning angle detecting device 27 detects a turning angle with respect to the lower traveling body 20.

A base end of the boom 8 of the front work implement 24 is supported to be vertically rotatable at a front portion of the upper slewing body 22, one end of the arm 9 is supported to be vertically rotatable at an end (tip end) different from the base end of the boom 8, and the bucket 10 is supported to be vertically rotatable at the other end of the arm 9. The boom 8, the arm 9, the bucket 10, the upper revolving structure 22, and the lower traveling structure 20 are driven by a boom cylinder 5, an arm cylinder 6, a bucket cylinder 7, a revolving motor 23, and left and right traveling motors 3 (only one traveling motor is shown) as hydraulic actuators, respectively.

Here, an intersection point of the rotation center axis 25 of the upper revolving structure 22 and the lower surface of the upper revolving structure 22 is set as an origin, and a y-axis body coordinate system having a z-axis which is positive from above along the rotation center axis 25, an x-axis which is positive from the front in the front-rear direction perpendicular to the z-axis from the origin, and a right direction which is positive from the origin in the left-right direction perpendicular to the z-axis and the x-axis is set.

A cab 2 on which a driver rides is mounted on the front left side of the upper revolving structure 22. Further, a control device 44 that controls the overall operation of the hydraulic excavator 100 is disposed on the upper slewing body 22. The cab 2 is provided with operation levers (operation devices) 2a and 2b that output operation signals for operating the hydraulic actuators 5 to 7 and 23. Although not shown, the operation levers 2a and 2b are each tiltable in the front, rear, left, and right directions, and include a detection device (not shown) that electrically detects a lever operation amount, which is a tilting amount of the lever as an operation signal, and the lever operation amount detected by the detection device is output to the control device 44 (described below) via an electric wiring. That is, the operations of the hydraulic actuators 5 to 7, 23 are distributed in the front-rear direction or the left-right direction of the operation levers 2a, 2b, respectively.

The operation control of the boom cylinder 5, the arm cylinder 6, the bucket cylinder 7, the swing motor 23, and the left and right travel motors 3 is performed by controlling the direction and flow rate of the hydraulic oil supplied to the hydraulic actuators 3, 5 to 7, 23 from a hydraulic pump device driven by a prime mover such as an engine or an electric motor, not shown, by a control valve or the like. The control valves are operated and controlled by the control device 44 based on operation signals from the operation levers 2a, 2b, thereby controlling the operations of the respective hydraulic actuators 5 to 7, 23.

Attitude sensors 34A, 34B, and 34C are attached to the base of the boom 8, the joint between the boom 8 and the arm 9, and the joint between the arm 9 and the bucket 10, respectively. The attitude sensors 34A, 34B, and 34C are mechanical angle sensors such as shifters (ポテンショメータ), for example. As shown in fig. 3, the attitude sensor 34A measures an angle β 1 formed by the longitudinal direction of the boom 8 (a straight line connecting the rotation centers of both ends) and the x-y plane, and sends the angle β 1 to the control device 44. Further, the attitude sensor 34B measures an angle β 2 formed by the longitudinal direction of the boom 8 (a straight line connecting the rotation centers at both ends) and the longitudinal direction of the arm 9 (a straight line connecting the rotation centers at both ends), and transmits the angle to the controller 44. Further, the attitude sensor 34C measures an angle β 3 formed by the longitudinal direction of the arm 9 (a straight line connecting the rotation centers at both ends) and the longitudinal direction of the bucket 10 (a straight line connecting the rotation center and the claw tip) and transmits the angle to the controller 44. Here, the turning angle detection device 27 and the attitude sensors 34A to 34C constitute an attitude detection device 60 for detecting attitude information of the upper turning body 22 and the front work implement 24.

In the present embodiment, the case where the swing center 38 of the front work implement 24 (the connection portion with the upper swing body 22 of the boom 8) is disposed at a position different from the swing center axis 25 is exemplified, but the swing center axis 25 may be disposed so as to intersect with the swing center 38.

In the present embodiment, the case where an angle sensor or the like is used as the attitude detecting device 60 is exemplified and described, but an Inertial Measuring Unit (IMU) may be used as the rotation angle detecting device 27 and the attitude sensors 34A to 34C. Further, stroke sensors may be disposed in the boom cylinder 5, the arm cylinder 6, and the bucket cylinder 7, respectively, and the relative directions (posture information) of the respective coupling portions of the upper revolving structure 22, the boom 8, the arm 9, and the bucket 10 may be calculated from the stroke change amounts, and the respective angles may be obtained from the results.

A plurality of (for example, 4) external environment recognition devices 26 for detecting objects around the excavator main body (the upper revolving structure 22 and the lower traveling structure 20) are disposed in the upper revolving structure 22. The installation position and the number of external environment recognition devices 26 are not particularly limited to the example of the present embodiment, and may be any as long as the field of view in all directions of the main body (i.e., 360 degrees around the excavator 100) can be ensured. In the present embodiment, a case will be described as an example where 4 external environment recognition devices 26 are provided in the upper portion of cab 2, the left side, the right side front portion, and the right side rear portion of upper revolving structure 22, respectively, and cover the 360-degree field of view around the main body. The external environment recognition device 26 is a sensor using, for example, LiDAR (Laser Imaging Detection and Ranging) technology, detects an object (for example, an obstacle 14 described later) present around the excavator 100, and transmits coordinate data thereof to the control device 44.

Fig. 3 is a functional block diagram schematically showing a part of processing functions of a control device mounted on the hydraulic excavator. Fig. 4 is a functional block diagram showing a part of the functions in fig. 3 in detail.

In fig. 3 and 4, the control device 44 includes a determination unit 31, an operation range calculation unit 35, a blind spot calculation unit 37, and a moving body course prediction unit 45. The operation range calculation unit 35 includes a posture calculation unit 43, a turning angle calculation unit 48, a speed limit region calculation unit 50, a front work machine speed calculation unit 51, and an angular speed calculation unit 52. The speed limit area calculation unit 50 includes a braking distance calculation unit 30 and a braking time calculation unit 49.

In fig. 3, the blind spot calculation unit 37 calculates a blind spot based on the relative positional relationship with respect to the upper revolving structure 22 obtained from the external environment recognition device 26. The operation range calculation unit 35 calculates a braking time based on the information obtained from the posture detection device 60, transmits the braking time to the moving body course prediction unit 45, and transmits the operation range of the main body to the determination unit 31. The operation performed by the operation range calculation unit 35 will be described in detail later. The moving body course prediction unit 45 determines whether or not there is a possibility of a moving body such as an operator entering from the position and shape of the obtained blind spot 16, calculates a range in which the moving body can move until the front work machine 24 brakes, and the virtual movement range 41, based on the obtained braking time of the front work machine 24, and transmits the calculated range to the determination unit 31. The determination unit 31 limits the speed of the working device 33 or determines whether or not to operate the alarm device 59 based on the information obtained by the moving body course prediction unit 45 and the operation range calculation unit 35. The details of the calculation by the determination unit 31 will be described later.

In fig. 4, the attitude calculation unit 43 calculates the length of the front work implement 24 based on the angle information of each of the boom 8, the arm 9, and the bucket 10 obtained by the attitude sensor 34, and transmits the calculated length to the speed limit area calculation unit 50. Further, in front work implement speed calculation unit 51, the speed at which front work implement 24 moves (front work implement speed) is calculated based on the change in the angle of each of boom 8, arm 9, and bucket 10 obtained by attitude sensor 34, and is transmitted to speed limit area calculation unit 50. The turning angle calculation unit 48 calculates the turning angle of the host vehicle 13 with the front direction of the lower traveling structure 20 set to 0 ° and the left turning direction of the upper turning structure 22 set to positive, and sends the calculated turning angle to the speed limitation region calculation unit 50. Further, the angular velocity calculation unit 52 calculates the angular velocity of the work implement 24 before the operation based on the change speed of the turning angle input from the turning angle detection device 27, and transmits the calculated angular velocity to the velocity limit area calculation unit 50. The speed limit region calculation unit 50 is composed of the braking distance calculation unit 30 and the braking time calculation unit 49. The braking distance calculation unit 30 calculates the braking distance of the front work machine 24 based on the front work machine length obtained by the posture calculation unit 43, the moving speed of the front work machine 24 obtained by the front work machine speed calculation unit 51, the turning angle obtained by the turning angle calculation unit 48, and the angular speed obtained by the angular speed calculation unit 52, and transmits the calculated braking distance to the determination unit 31. The braking time calculation unit 49 calculates the braking time of the front work implement 24 based on the front work implement length obtained by the posture calculation unit 43, the moving speed of the front work implement 24 obtained by the front work implement speed calculation unit 51, the turning angle obtained by the turning angle calculation unit 48, and the angular speed obtained by the angular speed calculation unit 52, and transmits the braking time to the moving body course prediction unit 45.

The control device 44 configured as described above calculates the blind spot range (blind spot 16) which is the range to become a blind spot based on the recognition range of the external environment recognition device from the object recognized by the external environment recognition device 26, calculates the assumed movement range 41 which is the range in which the mobile body 39 assumed to be present in the blind spot can move within a predetermined time, calculates the range in which the front work implement 24 can move within a predetermined time based on the posture information detected by the posture detection device 60, and performs the prevention control for preventing the mobile body 39 from contacting the front work implement 24 based on the assumed movement range 41 of the mobile body 39 and the movable range of the front work implement 24.

Fig. 13 is a flowchart showing the processing content of the prevention control.

In fig. 13, the controller 44 first determines whether or not there is an obstacle (step S101), and if the determination result is yes, detects the posture of the excavator main body (step S102), and performs a blind spot range calculation for calculating a blind spot due to the obstacle (step S103).

Next, it is determined whether or not there is a possibility that the mobile body enters a blind spot (step S104), and if the determination result is yes, the braking time calculation of the braking time of the work implement 24 before calculation is performed (step S105), the operation range calculation processing of the movement range of the work implement 24 before calculation is performed (step S106), and the assumed movement range calculation of the relative movement range of the mobile body is performed (step S107).

Next, it is determined whether or not there is a possibility that the mobile body may contact the front work machine 24 (step S108), and if the determination result is yes, the speed limit related to the driving of the front work machine 24 is determined (step S109), and the operation of the alarm device 59 and the control operation of the work speed are performed (step S110).

Next, it is determined whether or not the main body has stopped (step S111), and if the determination result is "no", the process of step S110 is repeated until the determination result is "yes". If the determination result in step S111 is yes, the process ends.

When the determination result in any of steps S101, S104, and S108 is "no", the process is terminated.

The prevention control as described above will be described in more detail.

First, a method of calculating the front work machine length R and the bucket height Zb shown in fig. 2 will be described. The front work machine length R is a distance R from the center pivot axis 25 to the front end of the front work machine 24. The lengths of the boom 8, the arm 9, and the bucket 10 are set to L1, L2, and L3, respectively. The angle β 1 formed by the x-y plane and the longitudinal direction of the boom 8 is measured by the attitude sensor 34A. An angle β 2 formed between the boom 8 and the arm 9 and an angle β 3 formed between the arm 9 and the bucket 10 are measured by the position sensors 34B and 34C, respectively. The height Z0 from the x-y plane to the center of oscillation 38 is predetermined. Further, a distance L0 from the rotation center axis 25 to the swing center 38 is also obtained in advance.

The angle β 2a formed by the xy plane and the longitudinal direction of the arm 9 can be calculated from the angle β 1 and the angle β 2. The angle β 3b formed by the xy plane and the longitudinal direction of the bucket 10 can be calculated from the angle β 1, the angles β 2, and β 3. The bucket height Zb and the front work machine length R can be calculated by the following (formula 1) and (formula 2).

Zb ═ Z0+ L1sin β 1+ L2sin β 2+ L3sin β 3 … (formula 1)

R ═ L0+ L1cos β 1+ L2cos β 2+ L3cos β 3 … (formula 2)

Next, a method of calculating the blind spot 16 by the controller 44 according to the first embodiment of the present invention will be described with reference to fig. 5 to 11. First, a dead angle calculation method in the xy plane will be described with reference to fig. 5. Based on the coordinates of the obstacle 14 obtained by the external environment recognition device 26, the obstacle position calculation unit 36 in the control device 44 calculates the relative angles θ xya and θ xyb and the relative distances XA and XB of the vehicle 13 and the left and right end portions 14A and 14B of the obstacle 14 on the xy plane. Based on these pieces of information, the blind spot calculation unit 37 calculates whether or not the blind spot 16 is present from the obstacle 14. In this case, the blind spot 16 is a range indicated by oblique lines, and when the front side of the detected obstacle 14 is set to the front, a region behind the position where the obstacle 14 is detected is recognized as the blind spot 16. That is, when the distances from the external environment recognition device 26 to the both end portions 14A and 14B of the obstacle 14 are XA and XB, respectively, the rear of the range of the angle θ xy between the distance XA and the XB from the external environment recognition device 26 to the end portion of the obstacle 14 is recognized as the blind spot 16. In addition, when the size of the blind spot 16 is smaller than the size of the general moving body (operator) 39, the blind spot 16 may be considered to be absent. This can avoid excessive control intervention.

Next, a method of detecting a blind spot on the xz plane will be described with reference to fig. 6 to 8.

As shown in fig. 6, when the height Z of the detected obstacle 14 is the same as the height Zs at which the external environment recognition device 26 is provided, the height of the blind spot 16 is defined as the height Z. The rear of the range of the angle θ xz of the distances XC and XD from the external environment recognition device 26 to the upper and lower ends 14C and 14D of the obstacle 14 is recognized as the blind spot 16.

On the other hand, as shown in fig. 7, when the height Z of the obstacle 14 is lower than the height Zs at which the external environment recognition device 26 is provided, the depth of the obstacle 14 can be calculated by the end portions 14C, 14D, and 14E of the obstacle 14. Here, since both ends of the obstacle 14 are 14D and 14E, the dead angle 16 is an angle between the distances XD and XE to the ends 14D and 14E of the obstacle 14. Since the external environment recognition device 26 is disposed at a position higher than the obstacle 14, the depth of the obstacle 14 can be detected, and therefore, it is preferable to provide the external environment recognition device 26 at a position as high as possible. Even when it is difficult to install the external environment recognition device 26 at a high position, the control may not be performed when the detected height Z is not a height at which the mobile body (operator) 39 can enter.

As shown in fig. 8, when the height Z of the detected obstacle 14 is higher than the height Zs at which the external environment recognition device 26 is provided, the angle between the upper end 14C of the obstacle 14 and the height Zs of the external environment recognition device 26 is θ xza, the angle between the lower end 14D of the obstacle 14 and the height Zs of the external environment recognition device 26 is θ xzb, and the region behind the obstacle 14 is recognized as the blind spot 16 within the range of the angle θ xzs, which is the sum of θ xza and θ xzb.

Next, a description will be given of a case where the bucket 10 of the vehicle 13 is a blind spot 16, with reference to fig. 9 to 11.

As shown in fig. 9, depending on the installation location of the external environment recognition device 26, the bucket 10 of the host vehicle 13 may be a blind spot 16. As shown in fig. 9, the bucket 10 blocks the view of the external environment recognition device 26 according to the posture of the excavator 100, thereby forming the dead angle 16. In this case, when the external environment recognition device 26 passes over the bucket 10 and can recognize the obstacle 14 locally, it is not determined as the dead angle 16.

As shown in fig. 10, when the external environment recognition device 26 is provided in the upper portion of the cab 2, the blind spot 16 is formed also in the xy plane. Therefore, as shown in fig. 11, for example, by providing the external environment recognition device 26 on the upper slewing body 22 on the opposite side of the front work implement 24 as viewed from the cab 2 side, the range of the blind spot 16 can be reduced. In this case, the dead angle 16 is identified as a range of an angle θ B from a dead angle line intersection point 58, which is a point where both dead angle lines 15 of the external environment identification devices 26a and 26B intersect, to a distance from the bucket tip end portions 57A and 57B. Here, the angle θ b is the sum of θ Ab and θ Bb.

Next, a method of calculating the speed limit region 40, the position where the movable body (operator) 39 can exist, and the virtual movement range 41, a method of dealing with the dead angle of the bucket 10, and a method of controlling the work implement 33 will be described with reference to fig. 12.

As shown in fig. 12, the angular velocity of the front work machine 24 at the current time point is ω, and the front work machine length is R. In this case, the angle θ t (braking angle) that is turned from the time point when the brake for stopping turning is activated until the front work implement 24 is stopped can be calculated by the following (equation 3) when the time from when the maximum braking force is applied until the brake is applied is t θ (turning braking time), the turning acceleration is α, and the initial angle is θ t 0.

θ t0+ ω × t θ + (α × t θ ^2)/2 … (formula 3)

Further, the distance xt (forward braking distance) that advances from the time point when the brake for stopping the forward movement is activated until the front work implement 24 is stopped can be calculated by the following (equation 4) when the forward speed v, the time (forward/reverse braking time) taken from the time point when the brake for stopping the forward and reverse movement is activated until the front work implement 24 is stopped is tx and the deceleration acceleration is a.

xt ═ v × tx + (a × tx ^2)/2 … (formula 4)

Therefore, in the speed limit region 40, when the forward braking distance is xt, the length of the front work implement is R, and the value of the sum of the distances L0 from the rotation center axis 25 to the swing center 38 is Rxt, the radius of rotation θ t of Rxt is set to be in the range. The speed limit region 40 when the front work 24 is retracted is a range in which the radius of the front work length R is turned by θ t.

Next, a method of calculating the assumed movement range 41 of the moving body (operator) 39 will be described. It is assumed that a moving body (operator) 39 existing in the blind spot 16 is present at a position in contact with both lines of the surface line 42 and the blind spot line 15 connecting both end portions 14A and 14B of the obstacle 14. In this case, the assumed movement range 41 of the moving body (operator) 39 is determined by the walking time of the moving body (operator) 39 and the distance r over which the moving body (operator) 39 can move. The walking time of the mobile body (operator) 39 selects a value at which the time until the front working machine 24 brakes in the front-rear direction and the turning direction is large. When the walking speed of the mobile body (operator) 39 is set to the average walking speed of the adult, the distance r over which the mobile body (operator) 39 can move is defined as the distance over which the mobile body (operator) 39 walks for the moving time. Therefore, the virtual movement range 41 is a range in which the distance r that enables the operator to move is turned by 360 ° from the surface of the moving body (operator) 39.

A method of dealing with a dead angle caused by the bucket 10 will be described. If the bucket 10 forms the dead angle 16, the information obtained by the external environment recognition device 26 before the formation of the dead angle can be used to complement the dead angle range, and excessive control can be suppressed.

The determination unit 31 determines whether or not the virtual movement range 41 calculated by the moving body course prediction unit 45 overlaps with the speed limit region 40 calculated by the operation range calculation unit 35, and when the virtual movement range 41 overlaps with the speed limit region 40 calculated by the operation range calculation unit 35, transmits a speed limit to the working device 33 or operates the alarm device 59. By providing such a determination unit 31, the probability of contact with a moving object emerging from the blind spot 16 can be reduced. Further, the speed limit area 40 may have a margin, the alarm device 59 may be operated when the movement range 41 is assumed to overlap the margin, and the speed limit may be applied to the working device 33 when the speed limit area 40 and the movement range 41 are assumed to overlap.

The effects of the present embodiment configured as described above will be described.

In construction machines such as hydraulic excavators in the construction and civil engineering industry, there is a conventional technique for controlling the operation speed of a front work machine as a technique for preventing contact between the front work machine performing work and an operator or the like. However, in the conventional technique, since the possibility that the moving body exists in the blind spot of the detected object is not considered, it is not possible to sufficiently cope with the case where the moving body appears from the blind spot.

In contrast, the present embodiment includes: a main body including a lower traveling structure and an upper revolving structure provided to be able to revolve with respect to the lower traveling structure; a multi-joint type front working machine which is mounted on the main body and is composed of a plurality of front components which are rotatably connected; a plurality of actuators that drive a plurality of front members of a front working machine, respectively, the construction machine including: a posture detection device which is provided on a front member of the front work machine and detects posture information of the front member; an external environment recognition device that detects an object around the subject; and a control device that calculates a blind spot range, which is a range to become a blind spot, based on the recognition range of the external environment recognition device, based on the object recognized by the external environment recognition device, calculates an assumed movement range, which is a range in which a moving body assumed to be present in the blind spot can move within a predetermined time, calculates a range, which is a range in which the front working machine can move within the predetermined time, based on the posture information detected by the posture detection device, and performs prevention control for preventing contact between the moving body and the front working machine based on the assumed movement range of the moving body and the movable range of the front working machine.

< second embodiment >

A second embodiment of the present invention will be described with reference to fig. 14 and 15.

In the first embodiment, the blind spot 16 is calculated from the relative distance and the relative angle to the obstacle 14 using the external environment recognition device 26, but the present embodiment includes, for example, a position measurement device 46 that measures the position of the own vehicle 13 based on a GPS signal or the like, and a wireless communication device 47 that receives information of the position of the obstacle 14 detected by the other vehicle 18, the position of the other vehicle 18, and the orientation of the main body, the wireless communication device 47 transmits information obtained from the other vehicle 18 to the blind spot calculation unit 37, and the blind spot calculation unit 37 calculates the blind spot 16, the position where the mobile body can exist, and the assumed movement range 41 of the mobile body (operator) 39 based on the information of the external environment recognition device 26, the position measurement device 46, and the wireless communication device 47.

Fig. 14 is a functional block diagram schematically showing a part of processing functions of the control device mounted on the hydraulic excavator according to the present embodiment. Fig. 15 is a diagram for explaining calculation of a blind spot in the present embodiment. In the drawings, the same components as those of embodiment 1 are denoted by the same reference numerals, and description thereof is omitted.

As shown in fig. 14, the position measurement device 46 transmits the coordinate position of the vehicle 13 to the blind spot calculation unit 37 based on, for example, a GPS signal. The wireless communication device 47 receives the information of the external environment recognition device 26 obtained by the other vehicle 18, the coordinate position of the other vehicle 18, and the direction of the main body of the other vehicle 18, and transmits the information to the blind spot calculation unit 37. The blind spot calculation unit 37 calculates the blind spot 16 based on the information from the position measurement device 46, the wireless communication device 47, and the external environment recognition device 26 of the host vehicle 13, and sends the blind spot to the moving object course prediction unit 45.

As shown in fig. 15, for example, when another vehicle 18 is present at a position on the side where the obstacle 14 can be detected from the inside and outside of the working range 17, the other vehicle 18 transmits the coordinate position of the vehicle, the direction of the body, and information of the external environment recognition device 26 via the wireless communication device 47. The host vehicle 13 receives information obtained from the other vehicle 18 via the wireless communication device 47, and the blind spot calculation unit 37 calculates the positional relationship with the host vehicle 13 based on the coordinate positions of the host vehicle 13 and the other vehicle 18. Further, the position of the obstacle 14 and the blind spot 16 detected by the other vehicle 18 are calculated from the direction of the main body of the other vehicle 18. Here, the blind spot 16 of the obstacle 14 detected by the host vehicle 13 is indicated by the range of the blind spot line 15a, and the blind spot 16 of the obstacle 14 detected by the other vehicle 18 is indicated by the range of the blind spot line 15 b.

Then, the blind spot calculation unit 37 compares the blind spot 16 calculated based on the information obtained from the own vehicle 13 with the blind spot 16 calculated based on the information of the other vehicle 18, and if the other vehicle 18 can detect a range determined as the blind spot 16 in the own vehicle 13, the range is not recognized as the blind spot 16. As a result, it is not necessary to perform speed limitation on the work and turning operation for the detected aspect of the other vehicle 18.

The other structure is the same as that of the first embodiment.

The present embodiment configured as described above can also obtain the same effects as those of embodiment 1.

< third embodiment >

A third embodiment of the present invention will be described with reference to fig. 16 to 18.

In the second embodiment, the relative distance and the relative angle to the obstacle 14 are obtained using a technique of acquiring coordinate data such as LiDAR from the external environment recognition device 26, and the blind spot 16 is calculated from the position information of the other vehicle 18, the relative distance and the relative angle to the obstacle 14, which are obtained from the position measurement device 46 that measures the position of the own vehicle 13 and the wireless communication device 47, but the present embodiment includes: a position estimation device that measures the position of the own vehicle 13; an image discrimination device 53 that uses an imaging target 14 such as a camera; a wireless communication device 47 that receives information from the other vehicle 18 via wireless communication; the external environment recognition device 26 transmits the relative distance and the relative angle to the obstacle 14 to the obstacle determination unit 54 and the obstacle determination unit 54, determines the obstacle 14 based on these pieces of information, and is additionally provided with a function of recognizing the obstacle 14 as another vehicle 18 based on these pieces of information, and determining the vehicle type.

Fig. 16 is a functional block diagram schematically showing a part of processing functions of the control device mounted on the hydraulic excavator according to the present embodiment. Fig. 17 is a diagram for explaining calculation of a blind spot in the present embodiment, and fig. 18 is a diagram for explaining an assumed movement range of a moving body in the present embodiment. In the drawings, the same components as those of the first and second embodiments are denoted by the same reference numerals, and descriptions thereof are omitted.

As shown in fig. 16, the position measuring device 46 transmits the coordinates of the host vehicle 13 to the obstacle discriminating unit 54. Further, the image discrimination device 53 images the obstacle 14 and transmits the image to the obstacle discrimination unit 54. The wireless communication device 47 transmits the position information and the vehicle type information of the other vehicle 18 mounted with the position measurement device 46 to the obstacle discriminating unit 54. The obstacle determination unit 54 compares the image of the construction machine stored in advance with the image obtained from the image determination device 53, and determines whether or not the obstacle 14 is the other vehicle 18. Further, the obstacle discriminating unit 54 calculates the positional relationship between the host vehicle 13 and the other vehicle 18 based on the position of the host vehicle 13 obtained from the position measuring device 46 and the positional information of the other vehicle 18 obtained from the wireless communication device 47, and recognizes the obstacle 14 as the other vehicle 18 when the position of the obstacle 14 obtained from the external environment recognizing device 26 matches the calculated position of the other vehicle 18.

As shown in fig. 17, since the type of the obstacle 14 can be determined by using the image determination device 53 and the obstacle determination unit 54, the blind spot 16 can be reduced by regarding a certain distance in the rear as the obstacle 14. As a result, the position where the moving body (operator) 39 is likely to be present can be reduced, and the probability that the assumed movement range 41 of the moving body (operator) 39 overlaps the speed limitation region 40 can be reduced.

Here, as shown in fig. 18, it is assumed that the position of the moving body (operator) 39 existing in the blind spot 16 is located at a position closest to the host vehicle 13, which is in contact with the side surface 56 of the obstacle 14 and the blind spot line 15. In addition, in the case where it is difficult to distinguish the obstacle 14 or the unregistered obstacle 14, the range of the blind spot is determined according to the blind spot detection method of embodiment 1.

The other structures are the same as those of the first and second embodiments.

The present embodiment configured as described above can also obtain the same effects as those of the first and second embodiments.

< appendix >)

The present invention is not limited to the above-described embodiments, and various modifications and combinations are possible within the scope of the invention. For example, the present invention is not limited to the embodiments having all the configurations described in the above embodiments, and includes embodiments in which a part of the configuration is deleted. The above-described structures, functions, and the like may be partially or entirely realized by, for example, an integrated circuit design or the like. The respective structures, functions, and the like described above may be implemented by software by interpreting and executing a program for implementing the respective functions by a processor.

Description of the reference numerals

2 … cab, 2a, 2b … operation lever (operation device), 3 … travel motor, 5 … boom cylinder, 6 … arm cylinder, 7 … bucket cylinder, 8 … boom, 9 … arm, 10 … bucket, 13 … own vehicle, 14 … obstacle (object), 15 … dead line, 15 … two dead lines, 16 … dead angle, 17 … working range, 18 … other vehicle, 20 … lower travel body, 21 … turning mechanism, 22 … upper turning body, 23 … turning motor, 24 … front working machine, 25 … turning center shaft, 26 … external environment recognition device, 27 … turning angle detection device, 30 … braking distance calculation unit, 31 … determination unit, 34 … attitude sensor, 35 … working range calculation unit, … obstacle position calculation unit, 3637 calculation unit, … swing center, 3639 working unit, … speed limit area (working area) and 3640 working area limit area), and … working area calculation unit, 41 … is a virtual movement range, 42 … surface lines, 43 … posture calculation unit, 44 … control device, 45 … moving body travel route prediction unit, 46 … position measurement device, 47 … wireless communication device, 48 … turning angle calculation unit, 49 … braking time calculation unit, 50 … speed limit area calculation unit, 51 … front work machine speed calculation unit, 52 … angular speed calculation unit, 53 … image discrimination device, 54 … obstacle discrimination unit, 59 … alarm device, 60 … posture detection device, 100 … hydraulic shovel.