JP6877385B2 - Work machine - Google Patents

Description

The present invention relates to a work machine such as a hydraulic excavator.

Work machines such as hydraulic excavators need to work in a state where the vehicle body is highly stable so that the vehicle body does not tip over during the work. The vehicle body stability referred to here is an index indicating the difficulty of the vehicle body falling, and means that the lower the vehicle body stability, the higher the possibility of the vehicle body falling. For example, Patent Document 1 discloses a prior art of a work machine capable of determining vehicle body stability.

Patent Document 1 describes the position and orientation of the lower traveling body, the upper rotating body mounted on the lower traveling body, the attachment attached to the upper rotating body, the operation content detecting device for detecting the operation content, and the position and orientation of the excavator. A shovel including a positioning device for measuring a body, a posture detecting device for detecting the posture of the attachment, and a control device. The control device has a ground shape information acquisition unit, and the posture detecting device detects the position. Whether the excavator is in a stable state or an unstable state based on the transition of the posture of the attachment, the information on the current shape of the work target ground acquired by the ground shape information acquisition unit, and the position of the excavator (vehicle body). A shovel that determines (stability) and limits the movement of the excavator when it is determined to be unstable is disclosed.

Japanese Unexamined Patent Publication No. 2016-172963

By the way, in a work machine such as a hydraulic excavator, high construction accuracy may be required, and in that case, it is necessary to ground the vehicle body on a highly stable ground. For example, when the vehicle body is grounded on soft ground (ground with low stability), the vehicle body vibrates due to the deformation of the ground due to its own weight or the reaction of the work, which makes precise work difficult.

Here, in the excavator described in Patent Document 1, although the vehicle body stability can be determined according to the shape of the ground on which the vehicle body is in contact with the ground, the deformation of the ground due to its own weight or the reaction of the work should be taken into consideration. Therefore, it is not possible to judge the stability of the ground. Therefore, at present, the operator judges the stability of the ground based on his / her own experience, and the work efficiency and the construction quality vary.

The present invention has been made in view of the above problems, and an object of the present invention is to provide a work machine capable of determining the stability of the ground on which the vehicle body is in contact with the ground and notifying the operator of the determination result. It is in.

In order to achieve the above object, the present invention comprises a vehicle body, a work machine attached to the vehicle body, a posture information acquisition device for acquiring posture information of the vehicle body and the work machine, an information output device, and the information. The controller includes a controller for controlling an output device, and the controller includes a dynamic center of gravity position estimation unit that estimates the dynamic center of gravity position of the work machine based on the attitude information, and the vehicle body based on the dimension information of the vehicle body. Body stability that calculates the vehicle body stability of the work machine according to the distance between the support range calculation unit that calculates the support range figure composed of the grounding points and the side that constitutes the dynamic center of gravity position and the support range figure. In a work machine having a degree calculation unit, the controller has an amplitude estimation unit that estimates the amplitude of the vehicle body based on the posture information of the vehicle body, and the vehicle body stability is higher than a predetermined stability and the amplitude is higher than a predetermined stability. When it is larger than a predetermined amplitude, it is determined that the ground stability, which is the stability of the ground on which the vehicle body is in contact with the ground, is low, the vehicle body stability is higher than the predetermined stability, and the amplitude is the predetermined amplitude. In the following cases, it is assumed that the ground stability determination unit is provided to determine that the ground stability is high and output the determination result to the information output device.

According to the present invention configured as described above, the ground stability is determined based on the amplitude of the vehicle body in a state where the vehicle body stability is higher than the predetermined stability, and the determination result is determined by the operator via the information output device. Will be notified. As a result, the operator can grasp the stability of the ground on which the vehicle body is in contact with the ground during the work.

According to the present invention, since the operator can grasp the stability of the ground on which the vehicle body of the work machine is in contact with the ground during the work, it is possible to suppress variations in work efficiency and construction quality.

It is a side view of the hydraulic excavator which concerns on 1st Example of this invention. It is a block diagram of the ground stability notification system mounted on the hydraulic excavator shown in FIG. It is a figure which shows the physical model of the hydraulic excavator used in each calculation of the controller shown in FIG. It is explanatory drawing which shows the calculation method of the vehicle body stability by the vehicle body stability calculation unit shown in FIG. It is explanatory drawing which shows the method of estimating the amplitude of the vehicle body by the amplitude estimation part shown in FIG. It is a flowchart which shows the determination method of the ground stability by the ground stability determination part in 1st Example of this invention. It is an external view of the information output device in the 1st Example of this invention. It is a block diagram of the ground stability notification system mounted on the hydraulic excavator according to the second embodiment of the present invention. It is a flowchart which shows the determination method of the ground stability by the ground stability determination part in the 2nd Example of this invention. It is a block diagram of the ground stability notification system mounted on the hydraulic excavator according to the third embodiment of the present invention. It is an external view of the permissible amplitude setting apparatus in 4th Example of this invention. It is a block diagram of the ground stability notification system mounted on the hydraulic excavator according to the 4th embodiment of the present invention. It is an external view of the permissible amplitude setting apparatus in 4th Example of this invention.

Hereinafter, a hydraulic excavator will be taken as an example as a work machine according to an embodiment of the present invention, and will be described with reference to the drawings. In each figure, the same members are designated by the same reference numerals, and duplicate description will be omitted as appropriate.

FIG. 1 is a side view of the hydraulic excavator according to the first embodiment of the present invention.

In FIG. 1, the hydraulic excavator 1 is provided on the lower traveling body 10 and the lower traveling body 10 so as to be rotatable, and can be rotated by the upper rotating body 11 and the upper rotating body 11 which form a vehicle body together with the lower traveling body 10. It is provided with a work front 12 provided.

The work front 12 includes a boom 13 rotatably provided on the upper swivel body 11, an arm 14 rotatably provided at the tip of the boom, a bucket 15 rotatably provided at the tip of the arm, and a boom. The boom cylinder 16 that drives the 13 and the arm cylinder 17 that drives the arm 14, the bucket cylinder 18 that drives the bucket 15, the link 19 that connects the bucket cylinder 18 and the arm 14, and the bucket cylinder 18 and the bucket 15 are connected. It is composed of a link 20, a pin 33 connecting the arm 14 and the bucket 15, and a pin 34 connecting the link 20 and the bucket 15.

The upper swivel body 11 is arranged in a swivel motor 21 that rotates the upper swivel body 11, an operation chamber 22 on which the operator gets in, and an operation chamber 22, and is used to convert operation information by the operator into a flood control signal. An operation lever 23 and a controller 24 for controlling the operation of the hydraulic excavator 1 are provided.

A boom IMU25, an arm IMU26, a bucket IMU27, and a vehicle body IMU28 are attached to the boom 13, arm 14, link 19, and upper swing body 11, respectively. IMU is an abbreviation for Inertial Measurement Unit (inertial measurement unit), which can detect angles (or angular velocities) and accelerations of three axes, and constitutes the work front 12, the boom 13, the arm 14, the bucket 15, and the upper part. It functions as an attitude information acquisition device 41 that acquires attitude information of the swivel body 11. The IMUs 25, 26, and 27 can acquire the rotation angles and angular velocities of the boom 13, arm 14, and bucket 15, respectively, and the IMU 28 can acquire the rotation direction, the rotation angle speed, the front-rear direction and the left-right direction of the upper swing body 11. It is configured so that the tilt angle of can be obtained. Further, inside the operation room 22, an information output device 31 that outputs a determination of the ground stability when the controller 24 determines that the ground stability is low is provided.
[System configuration]
FIG. 2 is a block diagram of a ground stability notification system mounted on the hydraulic excavator 1 according to the present embodiment.

The controller 24 includes a microcomputer (not shown) consisting of a CPU, a ROM, a RAM, a rewritable non-volatile storage means such as a flash memory, a computer program stored in the ROM, and peripheral circuits, and the computer program is stored on the CPU. Is configured to operate to perform arithmetic processing. The controller 24 is connected to the posture information acquisition device 41 composed of the IMUs 25 to 28 and the information output device 31. Further, the controller 24 determines the stability of the ground on which the hydraulic excavator 1 is in contact with the ground based on the posture information input from the posture information acquisition device 41, and outputs information when it is determined that the stability of the ground is low. The device 31 is configured to notify the operator.

In the controller 24, the hydraulic excavator 1 is formed at the ground contact point between the lower traveling body 10 and the ground surface 32 when the hydraulic excavator 1 is upright on a flat ground by using the dimensional information of the lower traveling body 10 stored inside the controller 24. Dynamic center of gravity position 70 of the hydraulic excavator 1 (shown in FIG. 4) based on the posture information from the support range calculation unit 42 that calculates the support range figure L (shown in FIG. 4) and the posture information acquisition device 41. The dynamic center of gravity position estimation unit 43 for estimating the above, the vehicle body stability calculation unit 44 for calculating the vehicle body stability of the hydraulic excavator 1 from the distance between the side forming the support range calculation figure L and the dynamic center of gravity position 70, and the posture information. Of the output of the acquisition device 41, the amplitude estimation unit 45 that estimates the amplitudes of the vehicle bodies 10 and 11 from the time-series changes in the front-rear tilt angle and the left-right tilt angle of the upper swing body 11 and the vehicle body stability are higher than the predetermined stability. It is provided with a ground stability determining unit 46 for determining that the ground stability is low when the amplitude is high and the amplitude is larger than a predetermined amplitude. Here, the vehicle body stability is an index showing the difficulty of the vehicle bodies 10 and 11 falling, and it means that the lower the vehicle body stability is, the higher the possibility that the vehicle bodies 10 and 11 will fall. On the other hand, the ground stability is an index showing the difficulty of deformation of the ground due to the weight of the hydraulic excavator 1 and the reaction of the work, and the lower the ground stability, the larger the vibration of the vehicle bodies 10 and 11 during the work. means.

The information output device 31 is configured to notify the operator of the hydraulic excavator 1 when the ground stability determination unit 46 determines that the ground stability is low. As the means for notifying, for example, at least one of a display device and an audio device (not shown) may be used. When using a display device, there are methods such as changing a message, changing a figure, and changing a lighting pattern. When using an audio device, there is a method of using changes in volume, pitch, and timbre.

Next, each process performed by the controller 24 will be described with reference to FIGS. 3 to 6.
[Explanation of calculation model]
FIG. 3 is a diagram showing a physical model of the hydraulic excavator 1 used for each calculation of the controller 24. The controller 24 performs operations in two coordinate systems, a world coordinate system (O-X'Y'Z') and a machine reference coordinate system (O-XYZ).

As shown in FIG. 3, the world coordinate system (OX'Y'Z') is based on the direction of gravity and the direction opposite to the direction of gravity as the Z axis. On the other hand, the machine reference coordinate system (O-XYZ) is based on the lower traveling body 10, and the origin is set as the point O in contact with the ground surface 32 on the turning center line 11c of the upper turning body 11, and the lower traveling body is set. The X-axis is set in the front-rear direction of 10, the Y-axis is set in the left-right direction, and the Z-axis is set in the turning center line 11c direction. The relationship between the world coordinate system and the machine reference coordinate system is detected by using the vehicle body IMU 28 described above.

As the physical model of the hydraulic excavator 1, a concentrated mass model in which the mass is concentrated at the center of gravity of each component is used.

The mass points 10P, 11P, 13P, 14P, and 15P of the lower traveling body 10, the upper swivel body 11, the boom 13, the arm 14, and the bucket 15 are set at the positions of the centers of gravity of each component, and the mass of each mass point is m10. Let it be m11, m13, m14, m15. Then, the position vectors of the respective mass points are r10, r11, r13, r14, r15, and the acceleration vectors r ″ 10, r ″ 11, r ″ 13, r ″ 14, r ″ 15.

The method of setting the mass point is not limited to this, and for example, a portion where the mass is concentrated (boom cylinder 16 or the like) may be added.

Further, the stability calculation index of the hydraulic excavator 1 in the support range calculation unit 42, the dynamic center of gravity position estimation unit 43, and the vehicle body stability calculation unit 44 is calculated based on ZMP (Zero Moment Point) and the ZMP stability discrimination standard. .. The concept of ZMP and ZMP stability discrimination norms is described in "LEGGED LOCOMATION ROBOTS: Miomir Vukobratovic (" Walking robot and artificial foot: Translated by Ichiro Kato, Nikkan Kogyo Shimbun ")".

Gravity, inertial force, external force and these moments act from the hydraulic excavator 1 to the ground surface 32, but according to D'Alembert's principle, these are the floor reaction force and the floor reaction as a reaction from the ground surface 32 to the hydraulic excavator 1. Balance with the moment of force.

Therefore, when the hydraulic excavator 1 is stably grounded on the ground surface 32, the pitch axis is on or inside the side of the support range figure L that connects the grounding points of the hydraulic excavator 1 and the ground surface 32 so as not to be concave. And there is a point (ZMP) where the moment in the roll axis direction becomes zero. Conversely, when ZMP exists in the support range diagram L and the force acting on the ground surface 32 from the hydraulic excavator 1 pushes the ground surface 32, that is, when the floor half force is positive, the hydraulic excavator 1 is stable. It can be said that it is grounded to.

That is, the closer the ZMP is to the center of the support range figure L, the higher the stability, and if it is inside the support range figure L, the hydraulic excavator 1 can perform the work without causing lifting, while the ZMP is in the support range. If it exists outside the figure L, the hydraulic excavator 1 may be lifted. Therefore, by using ZMP for the dynamic center of gravity position 70, the stability is calculated by comparing the support range figure L formed at the ground contact point between the hydraulic excavator 1 and the ground surface 32 with the dynamic center of gravity position 70. be able to.
[Support range graphic calculation]
The support range calculation unit 42 calculates the support range figure L that connects the ground contact points between the hydraulic excavator 1 and the ground surface 32 so as not to be concave, based on the dimensional information of the lower traveling body 10 registered in advance. It is configured.

When the lower traveling body 10 stands upright on the ground surface 32, the support range figure L becomes equal to the planar shape of the lower traveling body 10. Therefore, when the plane shape of the lower traveling body 10 is rectangular, the support range figure L is rectangular as shown in FIG. More specifically, in the support range figure L when the lower traveling body 10 has a crawler, the line connecting the center points of the left and right sprocket is the front boundary line, and the line connecting the center points of the left and right idlers is connected. Is a quadrangle with the rear boundary line and the outer ends of the left and right track links as the left and right boundary lines. The boundary between the front and the rear may be the grounding point of the frontmost lower roller and the rearmost lower roller.
[Dynamic center of gravity position estimation]
The dynamic center of gravity position estimation unit 43 is configured to calculate the dynamic center of gravity position 70 of the hydraulic excavator 1 from the output of the posture information acquisition device 41.

First, kinematics calculation is sequentially performed for each link from the output result of the posture information acquisition device 41. Then, the position vectors r10, r11, r13, r14, r15 of each mass point 10P, 11P, 13P, 14P, 15P and their acceleration vectors r ″ 10, r ″ 11, r ″ 13, r ″ 14, r '' 15 is calculated and converted into a value based on the machine reference coordinate system (O-XYZ).

Here, a well-known method can be used for the kinematics calculation method, and for example, the method described in "Robot Control Basic Theory: Tsuneo Yoshikawa, Corona Publishing Co., Ltd. (1988)" can be used.

The ZMP equation shown below is used to obtain the dynamic center of gravity position 70 using the position vector and acceleration vector of each mass point converted into the machine reference coordinate system (O-XYZ).

Here, rzmp: Dynamic center of gravity position vector mi: Mass of i-th mass point ri: Position vector of i-th mass point r'´i: Acceleration vector applied to i-th mass point (including gravitational acceleration)
Mj: The j-th external force moment sk: The k-th external force action point position vector Fk: The k-th external force vector. The vector is a three-dimensional vector composed of an X component, a Y component, and a Z component.

Since the origin O of the machine reference coordinate system is set at the point where the lower traveling body 10 and the ground surface 32 meet, assuming that the Z-axis coordinate of the dynamic center of gravity position 70 is on the ground surface 32, rzmpz = 0. is there. Further, since the external force can be ignored if the work is limited to the work without a load, it is considered that the external force Fk = 0 and the external force moment M = 0. Under such conditions, the equation (1) is solved, and the X coordinate rzmpx of the dynamic center of gravity position 70 is calculated as follows.

Similarly, the equation (1) is solved, and the Y coordinate rzmpy of the dynamic center of gravity position 70 is calculated as follows.

In the formulas (2) and (3), m is the mass of each mass point 10P, 11P, 13P, 14P, 15P shown in FIG. 3, and the mass m10, m11, m13, m14, m15 of each mass point is substituted. r ″ is the acceleration of each mass point, and the accelerations r ″ 10, r ″ 11, r ″ 13, r ″ 14, r ″ 15 of each mass point are substituted.

As described above, the coordinates of the estimated dynamic center of gravity position 70 can be obtained by using the posture information acquisition device 41 provided in each part of the hydraulic excavator 1.
[Car body stability calculation]
FIG. 4 is a diagram showing a method of calculating the vehicle body stability by the vehicle body stability calculation unit 44.

The vehicle body stability calculation unit 44 is configured to calculate the vehicle body stability based on the dynamic center of gravity position 70 and the support range figure L.

As shown in FIG. 4A, a half straight line extending from the center point Lc (Xlc, Ylc) of the support range figure L formed at the ground contact point between the hydraulic excavator 1 and the ground surface 32 toward the dynamic center of gravity position 70. The intersection C (Xc, Yc) between Lz and the side of the support range figure L is calculated. Then, the vehicle body stability α is calculated by the following equation using the ratio of the distance from the center Lc to the intersection C and the distance from the center Lc to the dynamic center of gravity position 70.

The larger the value of the vehicle body stability α, the closer the dynamic center of gravity position 70 is to the center of the support range figure L, which means that the vehicle bodies 10 and 11 are less likely to tip over.

A method for performing a simpler calculation will be described with reference to FIG. 4 (b). In this method, the ratio of the maximum value that can be taken in the support range figure L and the dynamic center of gravity position 70 is evaluated for each of the X coordinate and the Y coordinate of the vehicle body stability α. At this time, the ratio in the X-axis direction

And the ratio in the Y-axis direction

The smaller value is selected as the vehicle body stability α. Here, Xmax is the maximum value of the X coordinate that can be taken in the support range figure L, and Ymax is the maximum value of the Y coordinate that can be taken in the support range figure L.

Further, in the above, the method of calculating the vehicle body stability α using the ratio of the distance between the side portion of the support range figure L and the dynamic center of gravity position 70 has been shown, but the vehicle body stability is evaluated by logarithmically evaluating the distance ratio. The degree α may be calculated. By doing so, it is possible to express the stability change in the vicinity of the side of the support range figure L in more detail.
[Amplitude estimation]
FIG. 5 is an explanatory diagram showing a method of estimating the amplitudes of the vehicle bodies 10 and 11 by the amplitude estimation unit 45.

The amplitude estimation unit 45 is configured to estimate the amplitudes of the vehicle bodies 10 and 11 by using the front-rear inclination angle and the left-right inclination angle acquired from the vehicle body IMU 28 in the output of the posture information acquisition device 41.

As shown in FIG. 5, it is assumed that the front-rear tilt angle and the left-right tilt angle change like the tilt angle waveforms fx (t) and fy (t), respectively, with respect to the current time t.

From the n sampling data acquired in the sampling cycle of Δt seconds up to the current time t, the anteroposterior tilt amplitude Ampx is obtained. Specifically, it is calculated using the following standard deviation formula.

Here, μx: is the average value of the acquired sampling data fx (T).

Next, the left-right tilt amplitude Ampy is also calculated by the following equation in the same manner.

Here, μy: is the average value of the acquired sampling data fy (T).

In the above method, the tilt amplitude is estimated using the standard deviation of the tilt angle waveform in the past fixed section, but the tilt amplitude may be estimated using the Peak to Peak value of the tilt angle waveform in the past fixed section.

Regarding Δt and the number of samplings n, the number of samplings n is 10 or more at which the t-value in the 95% confidence interval of the standard deviation generally converges, and nΔt is 2 or more cycles of the vibration cycle when the hydraulic excavator 1 vibrates. It is desirable to set.

Next, the amplitude Amp of the vehicle bodies 10 and 11 is obtained by the following equation.

The amplitude Amp is not limited to the above method, and may be obtained by synthesizing by coordinate transformation using the front-back tilt angle and the left-right tilt angle.
[Ground stability judgment]
FIG. 6 is a flowchart showing a method of determining the ground stability by the ground stability determination unit 46. The ground stability determination unit 46 repeatedly executes the flow shown in FIG. 6 at a predetermined cycle.

In step S100, if it is determined that the vehicle body stability α is higher than the preset vehicle body stability threshold value, the process proceeds to step S101. If not, the ground stability determination is not performed and the process returns to step S100.

In step S101, if it is determined that the amplitude Amp is higher than the preset amplitude threshold value, the process proceeds to step S102, and if not, the process proceeds to step S103. Here, the amplitude threshold value is set to the required upper limit value of the amplitude.

Next, in step S102, it is determined that the ground stability is low, and in step S103, it is determined that the ground stability is high. Step S102 or S102 is continued, and in step S104, the ground stability determination is output and the process ends. Here, the vehicle body stability threshold value is set to 0 because the vibration accompanied by the lifting of the vehicle body occurs when it is 0 or less. However, the safety factor may be set and a value larger than 0 may be set in consideration of the accuracy of the sensor to be used, the modeling error, and the like (for example, 0.2). Further, the upper limit of the amplitude is defined by the error of the tilt angle measurement value in order to prevent erroneous detection due to the error of the measuring device. For example, it is defined by the standard deviation when the vehicle body is stopped for a predetermined time. If the standard deviation of the measured value is 0.5 degrees, set it to 1.5 degrees, which is three times that. The amplitude threshold value is not limited to the above method, and the maximum amplitude of the inclination angle when the vehicle body is stopped for a predetermined time is used, the specification value of the sensor is used, or at least two or more including the above method. The configuration may be set by using the maximum value in the combination.
[Information output device]
FIG. 7 is an external view of the information output device 31 in this embodiment.

The information output device 31 has a monitor display unit 31a and a light emitting unit 31b. A ground stability determination output unit 60 is arranged on the monitor display unit 31a. When it is determined that the ground stability is low, the ground stability determination output unit 60 displays a message indicating that the ground during work is unstable for a certain period of time.

The output method is not limited to the message method shown in FIG. 7, and may be changed to lighting an icon or a figure, or may be output by lighting or blinking the light emitting unit 31b. Further, the buzzer sound may be configured to be output by changing the pitch, changing the volume, changing the output pattern, or the like by the sound device. Further, at least two of the monitor display unit 31a, the light emitting unit 31b, and the audio device may be combined and output. The time for continuing the output may be set so that the operator can recognize the output, and is set to, for example, 1 second or more. When combining outputs, the combined time is set to be 1 second or longer in total.
[Action / Effect]
The hydraulic excavator 1 according to the present embodiment includes vehicle bodies 10, 11, working machines 12 attached to the vehicle bodies 10, 11, and posture information acquisition devices 41 for acquiring posture information of the vehicle bodies 10, 11, and the working machines 12. An information output device 31 and a controller 24 for controlling the information output device 31 are provided, and the controller 24 includes a dynamic center of gravity position estimation unit 43 that estimates the dynamic center of gravity position 70 of the hydraulic excavator 1 based on the attitude information. A support range calculation unit 42 that calculates a support range graphic L composed of grounding points of the vehicle bodies 10 and 11 based on the dimensional information of the vehicle bodies 10 and 11, a dynamic center of gravity position 70, and a side forming the support range graphic L. A vehicle body stability calculation unit 44 that calculates the vehicle body stability α of the hydraulic excavator 1 according to the distance from the vehicle body, and an amplitude estimation unit 45 that estimates the amplitude Amp of the vehicle bodies 10 and 11 based on the attitude information of the vehicle bodies 10 and 11. , The stability of the ground on which the vehicle bodies 10 and 11 are in contact with each other when the vehicle body stability α is higher than the predetermined stability (vehicle body stability threshold) and the amplitude Amp is larger than the predetermined amplitude (amplitude threshold). It is determined that the ground stability is low, and when the vehicle body stability α is higher than the predetermined stability and the amplitude Amp is equal to or less than the predetermined amplitude, it is determined that the ground stability is high, and the determination result is output to the information output device 31. It has a ground stability determination unit 46 and a ground stability determination unit 46.

According to the hydraulic excavator 1 according to the present embodiment configured as described above, the ground stability is determined based on the amplitude Amp of the vehicle body in a state where the vehicle body stability α is higher than the predetermined stability, and the determination result is obtained. The operator is notified via the information output device 31. As a result, the operator can grasp the stability of the ground on which the vehicle bodies 10 and 11 are in contact with the ground during the work, so that it is possible to suppress variations in work efficiency and construction quality.

The hydraulic excavator 1 according to the second embodiment of the present invention will be described focusing on the differences from the first embodiment.
[System configuration]
FIG. 8 is a block diagram of the ground stability notification system mounted on the hydraulic excavator 1 according to the present embodiment.

The hydraulic excavator 1 according to the present embodiment further includes a traveling state acquisition device 47 composed of a traveling pressure sensor 23a that acquires a hydraulic signal for transmitting traveling information among the operating information output from the operating lever 23. .. The traveling state acquisition device 47 is connected to the controller 24. Further, the output of the traveling state acquisition device 47 is input to the ground stability determination unit 46 and used for determining the ground stability. Further, the information output device 31 is configured to always notify while the ground stability is determined to be low, instead of the output method of notifying the information for a certain period of time after the ground stability is determined to be low.
[Ground stability judgment]
FIG. 9 is a flowchart showing a method of determining the ground stability by the ground stability determination unit 46 in this embodiment. The ground stability determination unit 46 repeatedly executes the flow shown in FIG. 9 at a predetermined cycle.

In step S200, it is determined from the output of the traveling state acquisition device 47 whether or not it is in a traveling state, and if it is in a traveling state, the process proceeds to step S204, it is determined that the ground stability is high, and the process proceeds to step S205 to determine the ground stability. Outputs the judgment and ends. If it is not in the running state, the process proceeds to step S201. Here, when the traveling state acquisition device 47 is the traveling pressure sensor 23a, the traveling state is determined to be traveling while the pressure value exceeds the value at which the traveling starts, and when not, it is determined to be stopped.

In step S201, if the vehicle body stability α is higher than the preset vehicle body stability threshold value and is stable, the process proceeds to step S202, otherwise the determination of the ground stability is not updated and the process proceeds to step S205. Outputs the ground stability judgment and ends. Here, the method of setting the vehicle body stability threshold value is the same as that of the first embodiment.

In step S202, if it is determined that the amplitude Amp is higher than the preset amplitude threshold value and the vibration is vibrating, the process proceeds to step S203. If not, the ground stability determination is not updated and the process proceeds to step S205. Outputs the ground stability judgment and ends. Here, the method of setting the amplitude threshold value is the same as that of the first embodiment.

Finally, in step S203, it is determined that the ground stability is low, the process proceeds to step S205, the ground stability determination is output, and the process ends.

The information output device 31 always outputs a notification while it is determined that the ground stability is low, that is, while the work is continued on the unstable ground. In addition, the output message or icon is output as a notification recommending the movement of the hydraulic excavator 1 or the change of the direction of the lower traveling body 10.
[Action / Effect]
The hydraulic excavator 1 according to the present embodiment further includes a traveling state acquisition device 47 for acquiring the traveling states of the vehicle bodies 10 and 11, and the ground stability determination unit 46 is traveling the vehicle bodies 10 and 11 based on the traveling state. Whether or not it is determined, the ground stability is determined only when the vehicle bodies 10 and 11 are not traveling, and the determination result is held until the vehicle bodies 10 and 11 start traveling.

According to the hydraulic excavator 1 configured as described above, when the ground during work is unstable, the operator can improve the work by encouraging the change or movement of the installation direction of the hydraulic excavator 1.

The hydraulic excavator 1 according to the third embodiment of the present invention will be described focusing on the differences from the second embodiment.
[System configuration]
FIG. 10 is a block diagram of the ground stability notification system mounted on the hydraulic excavator 1 according to the present embodiment.

In the present embodiment, the hydraulic excavator 1 according to the present embodiment, which allows the operator to set the required ground stability by selecting the work content, further includes an allowable amplitude setting device 48. The allowable amplitude setting device 48 is connected to the controller 24. The permissible amplitude setting device 48 includes a permissible amplitude input unit 49 for the operator to input a permissible amplitude numerically, and a permissible amplitude storage unit 50 that stores the input value of the permissible amplitude input unit 49 and transmits it to the controller 24. Further, the ground stability determination unit 46 determines the ground stability using the allowable amplitude input from the allowable amplitude storage unit 50 instead of the preset amplitude threshold value.
[Allowable amplitude setting device]
The permissible amplitude setting device 48 includes a microcomputer composed of a rewritable non-volatile storage means such as a CPU, ROM, RAM, and flash memory (not shown), a computer program stored in the ROM, and peripheral circuits on the CPU. It is configured to run a computer program in and perform arithmetic processing.

FIG. 11 is an external view of the allowable amplitude setting device 48. The allowable amplitude setting device 48 includes a touch panel 48a as a GUI (Graphic User Interface) that also serves as an input and a display. On the touch panel 48a, a keyboard 49a for inputting numerical values and an input value display unit 49b for confirming input values are arranged. The keyboard 49a and the input value display unit 49b constitute an allowable amplitude input unit 49.
[Ground stability judgment]
The flow executed by the ground stability determination unit 46 in this embodiment is the same as that in the second embodiment (shown in FIG. 9), but the allowable amplitude set by the allowable amplitude setting device 48 is used as the amplitude threshold value in step S202. It differs in that.
[Action / Effect]
The hydraulic excavator 1 according to the present embodiment further includes an allowable amplitude setting device 48 for setting an allowable amplitude as a predetermined amplitude (amplitude threshold), and the allowable amplitude setting device 48 for inputting a numerical value of the allowable amplitude. It has an allowable amplitude input unit 49 and an allowable amplitude storage unit 50 that stores a numerical value input to the allowable amplitude input unit 49 as the allowable amplitude.

According to the hydraulic excavator 1 configured as described above, the allowable amplitude can be changed in consideration of the difference in the allowable amplitude (allowable amplitude) for each work content such as simple excavation work and excavation of the finished surface. As a result, it is possible to work on the ground with appropriate stability without reducing the erroneous determination of the ground stability and lowering the work efficiency.

The hydraulic excavator 1 according to the fourth embodiment of the present invention will be described focusing on the differences from the third embodiment.
[System configuration]
FIG. 12 is a block diagram of the ground stability notification system mounted on the hydraulic excavator 1 according to the present embodiment.

In the allowable amplitude setting device 48, the work content selection unit 51 for the operator to select the work content and the allowable amplitude recorded in advance associated with the work content according to the work content are input to the allowable amplitude setting unit. , The permissible amplitude selection unit 52 is further provided.
[Allowable amplitude setting device]
FIG. 13 is an external view of the allowable amplitude setting device 48. A work content list of the work content selection unit 51 is displayed on the touch panel 48a, and the work content can be selected by selecting the list.

Returning to FIG. 12, the work content selected by the work content selection unit 51 is transmitted to the allowable amplitude selection unit 52 of the allowable amplitude setting device 48. The permissible amplitude selection unit 52 stores a plurality of preset work contents and the permissible amplitude associated with those work contents, and stores the permissible amplitude associated with the work contents selected by the work content selection unit 51. Search and output. The permissible amplitude storage unit 50 stores the permissible amplitude value output from the permissible amplitude selection unit 52 as the permissible amplitude setting value. Further, when the work content is not selected by the work content selection unit 51 and the allowable amplitude value is not output from the allowable amplitude selection unit 52, the allowable amplitude storage unit 50 uses the numerical value input by the allowable amplitude input unit 49 as the allowable amplitude. Set as a setting value.

For the allowable amplitude, set the reference value according to the following criteria.

1. 1. When there is a reference value described in the related standard of work content 2. 2. When there is a reference value of the tilt angle at which the function used in each work content determined by the manufacturer of the hydraulic excavator 1 can be used. When there is a reference value for the inclination angle calculated from the construction accuracy required for each work content and the dimensional information of the hydraulic excavator 1 When there is no clear reference value for 4.1 to 3 For example, the work content selection unit in FIG. Since the crane mode displayed in 51 has a related standard, the allowable amplitude is defined as 1 degree based on the tilt angle of 1 degree during traveling specified in the related standard according to the judgment standard 1.

In the load measurement mode, when the load measurement function is performed, a function that can tolerate vibrations of, for example, ± 3 degrees is used. Therefore, the allowable amplitude is defined as 3 degrees according to the judgment criterion 2.

In the case of the semi-automatic excavation mode and the semi-automatic excavation mode (finishing), the reference value changes depending on the construction accuracy and the machine dimensions, so the definition of the judgment standard 3 is followed. For example, when the toe position ± 10 cm is required and the class of the hydraulic excavator 1 is 20 tons, the maximum reach of the toes is 10 m, so the allowable amplitude is 0 from Arctan (10 m, 10 cm) ≈0.6 degrees. Defined as 6 degrees.

In the case of the normal excavation mode, since there is no clear reference value, it is defined according to the judgment criterion 4. In the determination criterion 4, the permissible amplitude selection unit 52 does not select the permissible amplitude, and the permissible amplitude storage unit 50 stores the permissible amplitude input by the permissible amplitude input unit 49.

The present invention is not limited to the work content shown in FIG. 13, and it is possible to store a reference value in advance in the allowable amplitude selection unit 52 in accordance with the above-mentioned determination criteria in various work contents so that the reference value can be selected.
[Action / Effect]
The hydraulic excavator 1 according to the present embodiment further includes an allowable amplitude setting device 48 for setting an allowable amplitude as a predetermined amplitude (amplitude threshold), and the allowable amplitude setting device 48 selects one of a plurality of work contents. The work content selection unit 51 for the purpose and the numerical value of the allowable amplitude associated with each of the plurality of work contents are stored, and the numerical value of the allowable amplitude associated with the work content selected by the work content selection unit 51 is selected. It further has an allowable amplitude selection unit 52, and also has an allowable amplitude storage unit 50 that stores a numerical value selected by the allowable amplitude selection unit 52 as the allowable amplitude.

According to the hydraulic excavator 1 according to the present embodiment configured as described above, the stability suitable for the work content can be intuitively set from the work content. Therefore, the work content due to an input error of the set value or the like. It is possible to prevent the setting of inappropriate stability and prevent the deterioration of construction quality.
<Others>
The present invention is not limited to the above-described examples, and includes various modifications. For example, the hydraulic excavator 1 used in the description of the above embodiment has an upper swing body 11, a boom 13, an arm 14, and a bucket 15, but the configuration of the work machine is not limited to this, and for example, instead of the bucket 15. The present invention can also be applied to a work machine having a structure including a lifting magnet, a grapple, and the like.

The object of application of the present invention is not limited to a hydraulic excavator, but can be applied to a work machine having a structure in which a work machine is attached to a moving body, such as a mobile crane.

In the above, a hydraulic excavator that drives a hydraulic cylinder has been described as an example, but for a work machine that drives a work machine with a fluid pressure cylinder such as a hydraulic cylinder or a pneumatic cylinder, or a work machine that drives a joint with an electric motor or the like. It is also possible to apply.

Each part of the controller 24 does not need to be mounted on one computer as shown in FIG. 2, and may be distributed to a plurality of computers capable of intercommunication. In this case, the installation location of the computer is not limited to the work machine.

Although the attitude information acquisition device 41 uses an IMU, the attitude can be determined by a distance measuring sensor that detects the stroke of the cylinder, a potentiometer or rotary encoder that acquires the relative angle of the joint, a gyro sensor that detects angular velocity or acceleration, an acceleration sensor, or the like. Any device that can be detected may be used, and these may be configured to be used in combination.

If the output of the posture information acquisition device 41 is used, the dynamic center of gravity position estimation unit 43 may be configured to estimate the dynamic center of gravity position 70 using information from another vehicle body information acquisition device. For example, even if a pin force sensor such as a strain gauge is attached to each of the pins 33 and 34, and the external force information and the position coordinates are substituted into the equation (1), the dynamic center of gravity position 70 is calculated. Good. Further, a pressure sensor may be attached to the cylinders 16 to 18 as an external force, the external force may be calculated using the pressure information and the attitude information, and the dynamic center of gravity position 70 may be estimated by substituting it into the equation (1). ..

In the above embodiment, the traveling state acquisition device 47 uses the pressure signal of the traveling command, but if the operating lever 23 is an electric type instead of the hydraulic type, the traveling state acquisition device 47 may be configured to use the electric signal of the traveling command. .. Further, instead of using the travel command signal, the acceleration of the vehicle body IMU 28 may be used to detect whether or not the vehicle is moving and substitute it. In addition, it may be configured to determine the presence or absence of traveling by using the change in coordinates by high-precision GPS. Further, any of the above may be combined to acquire the running state.

In the above embodiment, the allowable amplitude setting device 48 is configured as an independent device, but the controller 24 and the information output device 31 may be dispersed and configured. Further, at this time, an analog input device such as a switch or a potentiometer may be additionally connected to the controller 24 as an input device so that input can be performed as an alternative to the touch panel.

In the above embodiment, it is assumed that the operator gets on the operation room 22 provided on the hydraulic excavator 1 and operates the hydraulic excavator 1. However, there are cases where the hydraulic excavator 1 is operated remotely using wireless or the like. At the time of remote control, it is difficult to accurately grasp the posture of the work machine and the stability of the ground as compared with the time of boarding, and it is difficult for even a skilled operator to intuitively grasp the stability of the ground. Therefore, it is more effective at the time of remote control. In the remote-controlled work machine, an information output device 31 may be provided near the operation location of the operator so as to additionally provide information on the hydraulic excavator 1.

1 ... hydraulic excavator (working machine), 10 ... lower traveling body (body), 11 ... upper turning body (body), 12 ... work front (working machine), 13 ... boom, 14 ... arm, 15 ... bucket, 16 ... Boom cylinder, 17 ... arm cylinder, 18 ... bucket cylinder, 19, 20 ... link, 21 ... swivel motor, 22 ... operation room, 23 ... operation lever, 23a ... running pressure sensor, 24 ... controller, 25 ... boom IMU, 26 ... Arm IMU, 27 ... Bucket IMU, 28 ... Body IMU, 31 ... Information output device, 31a ... Monitor display unit, 31b ... Light emitting unit, 32 ... Ground surface, 33, 34 ... Pins, 41 ... Attitude information acquisition device, 42 ... Support range calculation unit, 43 ... Dynamic center of gravity position estimation unit, 44 ... Body stability calculation unit, 45 ... Vibration estimation unit, 46 ... Ground stability determination unit, 47 ... Running state acquisition device, 48 ... Allowable amplitude setting unit , 48a ... Touch panel, 49 ... Allowable amplitude input unit, 49a ... Keyboard, 49b ... Input value display unit, 50 ... Allowable amplitude storage unit, 51 ... Work content selection unit, 52 ... Allowable amplitude selection unit, 60 ... Ground stability determination Output unit, 70 ... Dynamic center of gravity position.

Claims (5)

With the car body
The work machine attached to the car body and
A posture information acquisition device that acquires posture information of the vehicle body and the work machine, and
Information output device and
In a work machine equipped with a controller for controlling the information output device,
The controller
A dynamic center of gravity position estimation unit that estimates the dynamic center of gravity position of the work machine based on the posture information,
A support range calculation unit that calculates a support range figure composed of ground points of the vehicle body based on the dimensional information of the vehicle body, and a support range calculation unit.
A vehicle body stability calculation unit that calculates the vehicle body stability of the work machine according to the distance between the dynamic center of gravity position and the side forming the support range figure.
An amplitude estimation unit that estimates the amplitude of the vehicle body based on the posture information of the vehicle body,
When the vehicle body stability is higher than the predetermined stability and the amplitude is larger than the predetermined amplitude, it is determined that the ground stability, which is the stability of the ground on which the vehicle body is in contact with the ground, is low, and the vehicle body stability is determined. When the amplitude is higher than the predetermined stability and the amplitude is equal to or less than the predetermined amplitude, it is determined that the ground stability is high, and the ground stability determination unit for outputting the determination result to the information output device is provided. A work machine characterized by. In the work machine according to claim 1,
Further equipped with a running state acquisition device for acquiring the running state of the vehicle body,
The ground stability determination unit determines whether or not the vehicle body is traveling based on the traveling state, determines the ground stability only when the vehicle body is not traveling, and the vehicle body starts traveling. A work machine characterized in holding the judgment result until it is done. In the work machine according to claim 1,
A work machine further provided with an allowable amplitude setting device for setting the allowable amplitude as the predetermined amplitude. In the work machine according to claim 3,
The allowable amplitude setting device is
An allowable amplitude input unit for inputting a numerical value of the allowable amplitude, and
A work machine having a permissible amplitude storage unit that stores a numerical value input to the permissible amplitude input unit as the permissible amplitude. In the work machine according to claim 3,
The allowable amplitude setting device is
A work content selection unit for selecting one of multiple work contents,
It further has an allowable amplitude selection unit that stores a numerical value of the allowable amplitude associated with each of the plurality of work contents and selects a numerical value of the allowable amplitude associated with the work content selected by the work content selection unit. ,
A work machine having a permissible amplitude storage unit that stores a numerical value selected by the permissible amplitude selection unit as the permissible amplitude.

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